Brazilian Journal of Cardiovascular Surgery 27.3 - 2012

AR SURGERY ARDIO REVIST A BRASILEIRA DE CIRURGIA C ARDIO VASCUL AR/ BRAZILIAN JOURNAL OF C ASCULAR ARDIOV CARDIO REVISTA CARDIO ARDIOV ASCULAR/ VASCUL

27.3 JULY/SEPTEMBER 2012

V OL. 27 Nยบ 3 JUL Y/SEPTEMBER 2012 VOL. JULY/SEPTEMBER

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Qualidade e Segurança

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EDITOR/EDITOR Prof. Dr. Domingo M. Braile - PhD

REVIST A BRASILEIRA DE REVISTA CIRURGIA C A RDIO VASCUL AR CA RDIOV BRAZILIAN JOURNAL OF CARDIOVASCULAR SURGERY

São José do Rio Preto - SP - Brasil domingo@braile.com.br EDITORES ANTERIORES/FORMER EDITORS • Prof. Dr. Adib D. Jatene PhD - São Paulo (BRA) [1986-1996] • Prof. Dr. Fábio B. Jatene PhD - São Paulo (BRA) [1996-2002]

ASSESSORA EDITORIAL/EDITORIAL ASSISTANT Rosangela Monteiro PhD - São Paulo (BRA) rosangela.monteiro@incor.usp.br

EDITOR EXECUTIVO EXECUTIVE EDITOR Ricardo Brandau Pós-graduado em Jornalismo Científico - S. José do Rio Preto (BRA) brandau@sbccv.org.br

EDITORES ASSOCIADOS/ASSOCIATE EDITORS • • • • • • •

Antônio Sérgio Martins Gilberto Venossi Barbosa José Dario Frota Filho José Teles de Mendonça Luciano Cabral Albuquerque Luis Alberto Oliveira Dallan Luiz Felipe Pinho Moreira

Botucatu (BRA) Porto Alegre (BRA) Porto Alegre (BRA) Aracaju (BRA) Porto Alegre (BRA) São Paulo (BRA) São Paulo (BRA)

• • • • • • •

Manuel Antunes Mario Osvaldo P. Vrandecic Michel Pompeu B. Oliveira Sá Paulo Roberto Slud Brofman Ricardo C. Lima Ulisses A. Croti Walter José Gomes

Coimbra (POR) Belo Horizonte (BRA) Recife (BRA) Curitiba (BRA) Recife (BRA) S.J. Rio Preto (BRA) São Paulo (BRA)

EDITOR DE ESTATÍSTICA/STATISTICS EDITOR • Orlando Petrucci Jr.

Campinas (BRA)

CONSELHO EDITORIAL/EDITORIAL BOARD • Adib D. Jatene • Adolfo Leirner • Adolfo Saadia • Alan Menkis • Alexandre V. Brick • Antônio Carlos G. Penna Jr. • Bayard Gontijo Filho • Borut Gersak • Carlos Roberto Moraes • Christian Schreiber • Cláudio Azevedo Salles • Djair Brindeiro Filho • Eduardo Keller Saadi • Eduardo Sérgio Bastos • Enio Buffolo • Fábio B. Jatene • Fernando Antônio Lucchese • Gianni D. Angelini • Gilles D. Dreyfus • Ivo A. Nesralla • Jarbas J. Dinkhuysen • José Antônio F. Ramires • José Ernesto Succi • José Pedro da Silva • Joseph A. Dearani

São Paulo (BRA) São Paulo (BRA) Buenos Aires (ARG) Winnipeg (CAN) Brasília (BRA) Marília (BRA) Belo Horizonte (BRA) Ljubljana (SLO) Recife (BRA) Munique (GER) Belo Horizonte (BRA) Recife (BRA) Porto Alegre (BRA) Rio de Janeiro (BRA) São Paulo (BRA) São Paulo (BRA) Porto Alegre (BRA) Bristol (UK) Harefield (UK) Porto Alegre (BRA) São Paulo (BRA) São Paulo (BRA) São Paulo (BRA) São Paulo (BRA) Rochester (USA)

VERSÃO PARA O INGLÊS/ENGLISH VERSION • Alexandre Werneck • Fernando Pires Buosi • Marcelo Almeida • Pablo Sebastian Maluf

• • • • • • • • • • • • • • • • • • • • • • • •

Joseph S. Coselli Luiz Carlos Bento de Souza Luiz Fernando Kubrusly Mauro Paes Leme de Sá Miguel Barbero Marcial Milton Ary Meier Nilzo A. Mendes Ribeiro Noedir A. G. Stolf Olivio Souza Neto Otoni Moreira Gomes Pablo M. A. Pomerantzeff Paulo Manuel Pêgo Fernandes Paulo P. Paulista Paulo Roberto B. Évora Pirooz Eghtesady Protásio Lemos da Luz Reinaldo Wilson Vieira Renato Abdala Karam Kalil Renato Samy Assad Roberto Costa Rodolfo Neirotti Rui M. S. Almeida Sérgio Almeida de Oliveira Tomas A. Salerno

Houston (USA) São Paulo (BRA) Curitiba (BRA) Rio de Janeiro (BRA) São Paulo (BRA) Rio de Janeiro (BRA) Salvador (BRA) São Paulo (BRA) Rio de Janeiro (BRA) Belo Horizonte (BRA) São Paulo (BRA) São Paulo (BRA) São Paulo (BRA) Ribeirão Preto (BRA) Cincinatti (USA) São Paulo (BRA) Campinas (BRA) Porto Alegre (BRA) São Paulo (BRA) São Paulo (BRA) Cambridge (USA) Cascavel (BRA) São Paulo (BRA) Miami (USA)

ÓRGÃO OFICIAL DA SOCIEDADE BRASILEIRA DE CIRURGIA CARDIOVASCULAR DESDE 1986 OFFICIAL ORGAN OF THE BRAZILIAN SOCIETY OF CARDIOVASCULAR SURGERY SINCE 1986

ENDEREÇO/ADDRESS

Sociedade Brasileira de Cirurgia Cardiovascular Rua Beira Rio, 45 • 7º andar - Cj. 72 • Vila Olímpia • Fone: 11 3849-0341. Fax: 11 5096-0079.

Cep: 04548-050 • São Paulo, SP, Brasil E-mail RBCCV: revista@sbccv.org.br • E-mail SBCCV: sbccv@sbccv.org.br • Site SBCCV: www.sbccv.org.br • Sites RBCCV: www.scielo.br/rbccv / www.rbccv.org.br (também para submissão de artigos)

Publicação trimestral/Quarterly publication Edição Impressa - Tiragem: 240 exemplares (*)

REVISTA BRASILEIRA DE CIRURGIA CARDIOVASCULAR (Sociedade Brasileira de Cirurgia Cardiovascular) São Paulo, SP - Brasil. v. 119861986, 1: 1,2 1987, 2: 1,2,3 1988, 3: 1,2,3 1989, 4: 1,2,3 1990, 5: 1,2,3 1991, 6: 1,2,3 1992, 7: 1,2,3,4 1993, 8: 1,2,3,4 1994, 9: 1,2,3,4

1995, 10: 1,2,3,4 1996, 11: 1,2,3,4 1997, 12: 1,2,3,4 1998, 13: 1,2,3,4 1999, 14: 1,2,3,4 2000, 15: 1,2,3,4 2001, 16: 1,2,3,4 2002, 17: 1,2,3,4 2003, 18: 1,2,3,4

2004, 19: 1,2,3,4 2005, 20: 1,2,3,4 2006, 21: 1 [supl] 2006, 21: 1,2,3,4 2007, 22: 1 [supl] 2007, 22: 1,2,3,4 2008, 23: 1 [supl] 2008, 23: 1,2,3,4 2009, 24: 1 [supl]

2009, 24: 1,2,3,4 2009, 24: 2 [supl] 2010, 25: 1,2,3,4 2010, 25: 1 [supl] 2011, 26: 1,2,3,4 2011, 26: 1 [supl] 2012, 27: 1,2 2012, 27: 1 [supl]

ISSN 1678-9741 - Publicação online ISSN 0102-7638 - Publicação impressa RBCCV 44205

CDD 617.4105 NLM18 WG 168

(*) ASSOCIAÇÃO PAULISTA DE BIBLIOTECÁRIOS. Grupo de Bibliotecários Biomédicos.

Normas para catalogação de publicações seriadas nas bibliotecas especializadas.

São Paulo, Ed. Polígono, 1972

INDEXADA EM • Thomson Scientific (ISI) http://science.thomsonreuters.com • PubMed/Medline www.ncbi.nlm.nih.gov/sites/entrez

• ADSAUDE - Sistema Especializado de Informação em Administração de Saúde www.bibcir.fsp.usp.br/html/p/ pesquisa_em_bases_de_dados/ programa_rede_adsaude

• SciELO - Scientific Library Online www.scielo.br

• Index Copernicus www.indexcopernicus.com

• Scopus www.info.scopus.com

• Google scholar http://scholar.google.com.br/scholar

• LILACS - Literatura Latino-Americana e do Caribe em Ciências da Saúde. www.bireme.org • LATINDEX -Sistema Regional de Información en Línea para Revistas Cientificas de America Latina, el Caribe, España y Portugal www.latindex.uam.mx

Distribuída gratuitamente a todos os sócios da Sociedade Brasileira de Cirurgia Cardiovascular

SOCIEDADE BRASILEIRA DE CIRURGIA CARDIOVASCULAR BRAZILIAN SOCIETY OF CARDIOVASCULAR SURGERY DEPARTAMENTO DE CIRURGIA DA SOCIEDADE BRASILEIRA DE CARDIOLOGIA DEPARTMENT OF SURGERY OF THE BRAZILIAN SOCIETY OF CARDIOLOGY

“Valorizando o profissional em prol do paciente” DIRETORIA 2011 - 2013 Presidente: Vice-Presidente: Secretário Geral: Tesoureiro: Diretor Científico:

Walter José Gomes (SP) João Alberto Roso (RS) Marcelo Matos Cascudo (RN) Eduardo Augusto Victor Rocha (MG) Fábio Biscegli Jatene (SP)

Conselho Deliberativo:

Bruno Botelho Pinheiro (GO) Henrique Barsanulfo Furtado (TO) José Glauco Lobo Filho (CE) Rui M.S. Almeida (PR) Henrique Murad (RJ)

Editor da Revista: Editor do Site: Editores do Jornal:

Domingo Marcolino Braile (SP) Vinicius José da Silva Nina (MA) Walter José Gomes (SP) Fabricio Gaburro Teixeira (ES) Josalmir José Melo do Amaral (RN) Luciana da Fonseca (SP)

Presidentes das Regionais Afiliadas Norte-nordeste: Rio de Janeiro: São Paulo: Minas Gerais: Centro-Oeste: Rio Grande do Sul: Paraná: Santa Catarina:

Maurílio Onofre Deininger (PB) Marcelo Sávio da Silva Martins Carlos Manuel de Almeida Brandão AntonioAugusto Miana Luiz Carlos Schimin (DF) Marcela da Cunha Sales Rodrigo Mussi Milani Lourival Bonatelli Filho

Departamentos DCCVPED: DECAM: DECA: DECEN: DEPEX: DECARDIO:

Marcelo B. Jatene (SP) Alfredo Inácio Fiorelli (SP) Wilson Lopes Pereira (SP) Rui M. S. Almeida (PR) Melchior Luiz Lima (ES) Miguel Angel Maluf (SP)

SOCIEDADE BRASILEIRA DE CIRURGIA CARDIOVASCULAR BRAZILIAN SOCIETY OF CARDIOVASCULAR SURGERY E-mail: revista@sbccv.org.br Sites: www.scielo.br/rbccv www.rbccv.org.br

REVISTA BRASILEIRA DE CIRURGIA CARDIOVASCULAR

ISSN 1678-9741 - Publicação online ISSN 0102-7638 - Publicação impressa RBCCV 44205

Fator de Impacto: 1,239

BRAZILIAN JOURNAL OF CARDIOVASCULAR SURGERY Rev Bras Cir Cardiovasc, (São José do Rio Preto, SP - Brazil) jul/sep - 2012;27(3):347-502

CONTENTS/SUMÁRIO

EDITORIALS/EDITORIAIS BJCVS on social networks Domingo M. Braile ....................................................................................................................................................................... I The real world in diagnosis and treatment of acute coronary syndrome in Brazil Eduardo Augusto Victor Rocha ................................................................................................................................................... IV ORIGINAL ARTICLES/ARTIGOS ORIGINAIS 1392

Associated factors with survivals in patients undergoing orthotopic heart transplant using retrograde blood microcardioplegia Fatores associados à sobrevida em pacientes submetidos a transplante cardíaco utilizando microcardioplegia sanguínea retrógrada Carlos Fernando Ramos Lavagnoli, Elaine Soraya Barbosa de Oliveira Severino, Karlos Alexandre de Souza Vilarinho, Lindemberg da Mota Silveira Filho, Pedro Paulo Martins de Oliveira, Orlando Petrucci, Reinaldo Wilson Vieira, Domingo Marcolino Braile ........ 347

1393

Transcatheter aortic valve-in-valve implantation: a selection change?

Implante valve-in-valve transcateter em posição aórtica: uma mudança de seleção?

Diego Felipe Gaia, Aline Couto, João Roberto Breda, Carolina Baeta Neves Duarte Ferreira, Murilo Teixeira Macedo, Marcus Vinicius Gimenes, Enio Buffolo, José Honório Palma .............................................................................................................. 355

1394

Inspiratory muscle training improves tidal volume and vital capacity after CABG surgery Treinamento muscular melhora o volume corrente e a capacidade vital no pós-operatório de revascularização do miocárdio Gabriela Bertolini Matheus, Desanka Dragosavac, Patrícia Trevisan, Cledycion Eloy da Costa, Maurício Marson Lopes, Gustavo Calado de Aguiar Ribeiro .......................................................................................................................................................... 362

1395

Proposal of an individual scientometric index with emphasis on ponderation of the effective contribution of the first author: h-fac index Proposta de um índice cientométrico individual, com ênfase na ponderação positiva da participação do primeiro autor: índice h-fac Francisco Gregori Júnior, Moacir Fernandes de Godoy, Francisco Ferreira Gregori ................................................................ 370

1396

Long term mortality of deep sternal wound infection after coronary artery bypass surgery Mortalidade em longo prazo da infecção esternal profunda após cirurgia de revascularização do miocárdio Aline Alexandra Iannoni de Moraes, Cely Saad Abboud, André Zeraik Limma Chammas, Yara Santos Aguiar, Lucas Cronemberger Mendes, Jonatas Melo Neto, Pedro Silvio Farsky ................................................................................................................... 377

1397

Initial experience with minimally invasive cardiac operations Experiência Inicial com operações cardíacas minimamente invasivas Francisco Costa, Guilherme Winter, Andrea Dumsch de Aragon Ferreira, Tadeu Augusto Fernandes, Claudinei Collatusso, Fernanda Tome Tremel, Fabio Rocha Farias, Daniele de Fatima Fornazari ............................................................................. 383

1398

Biocompatibility of ricinus comunnis polymer compared to titanium implant used in artificial hearts. Experimental study in guinea pigs Biocompatibilidade do polímero da mamona comparada ao implante de titânio para corações artificiais. Estudo experimental em cobaias Luiz Fernando Kubrusly, Yorgos Luiz Santos de Salles Graça, Enéas Eduardo Sucharski, Ana Cristina Lira Sobral, Marcia Olandoski, Fernando Bermudez Kubrusly ............................................................................................................................... 392

1399

Intraoperative coronary grafts flow measurement using the TTFM flowmeter: results from a domestic sample Medida do fluxo intraoperatório com fluxômetro TTFM nos enxertos coronários: resultados de amostra nacional José Ernesto Succi, Luis Roberto Gerola, Guilherme de Menezes Succi, Hyong Chun Kim, Jorge Edwin Morocho Paredes, Enio Bufollo ............................................................................................................................................................................. 401

1400

Influence of fresh frozen plasma as a trigger factor for kidney dysfunction in cardiovascular surgery Plasma fresco congelado como fator de risco para a disfunção renal no pós-operatório de cirurgia cardiovascular Valdir Carlos Parreiras, Isabella de Sá Rocha, Antônio Sérgio Martins, Enoch Brandão de Souza Meira, Fábio Papa Taniguchi ...... 405

1401

Time of arrival of patients with acute myocardial infarction to the emergency department Tempo de chegada do paciente com infarto agudo do miocárdio em unidade de emergência Alessandra Soler Bastos, Lúcia Marinilza Beccaria, Ligia Márcia Contrin, Cláudia Bernardi Cesarino ................................... 411

1402

Replacement of pulmonary artery trunk in sheep using tubular valved heterograft in non-aldehydic preservation Substituição do tronco da artéria pulmonar em carneiros utilizando heteroenxerto tubular valvado com preservação não-aldeídica Helmgton José Brito de Souza, José Honório de Almeida Palma, Ivan Sérgio Joviano Casagrande, Sérgio Campo Christo, Luíz Sérgio Alves-Silva, Marco Antônio Cardoso de Almeida, Diego Felipe Gaia, Enio Buffolo .................................................... 419

1403

Assesment of CABDEAL score as predictor of neurological dysfunction after on-pump coronary artery bypass grafting surgery Avaliação do escore CABDEAL como preditor de disfunção neurológica no pós-operatório de revascularização miocárdica com circulação extracorpórea Vinícius José da Silva Nina, Maria Iracema de Amorim Rocha, Rayssa Fiterman Rodrigues, Vanessa Carvalho de Oliveira, João Lívio Linhares Teixeira, Eduardo Durans Figueredo, Rachel Vilela de Abreu Haickel Nina, Carlos Antonio Coimbra Sousa ................ 429

REVIEW ARTICLE/ARTIGO DE REVISÃO 1404

Gaseous microemboli in cardiac surgery with cardiopulmonary bypass: the use of veno-arterial shunt as a preventive method Microembolia gasosa em operação cardíaca com uso de circulação extracorpórea: emprego de shunt veno-arterial como método preventivo Edison Emidio dos Reis, Livia Dutra de Menezes, Caio César Lanaro Justo .......................................................................... 436

SCIENTIC UPDATE/ATUALIZAÇÃO CIENTÍFICA 1405

Noninvasive mechanical ventilation in the postoperative cardiac surgery period: update of the literature Ventilação mecânica não invasiva no pós-operatório de cirurgia cardíaca - Atualização da literatura Lucas Lima Ferreira, Naiara Maria de Souza, Ana Laura Ricci Vitor, Aline Fernanda Barbosa Bernardo, Vitor Engrácia Valenti, Luiz Carlos Marques Vanderlei ......................................................................................................................................................... 446

SPECIAL ARTICLES/ARTIGOS ESPECIAIS 1406

Reflections engendered as a practicing translator concerning the language of Anatomy Reflexões de um tradutor na área da Anatomia Humana Alexandre Lins Werneck ........................................................................................................................................................... 453

1407

A reflection on the performance of pediatric cardiac surgery in the State of São Paulo Uma reflexão sobre o desempenho da cirurgia cardíaca pediátrica no Estado de São Paulo Luiz Fernando Caneo, Marcelo Biscegli Jatene, Nelson Yatsuda, Walter J Gomes .................................................................. 457

1408

Analysis of ordinances regulating the national policy of high complexity cardiovascular care Análise das portarias que regulamentam a Política Nacional de Atenção Cardiovascular de Alta Complexidade Valdester Cavalcante Pinto Júnior, Maria Nazaré de Oliveira Fraga, Sílvia Maria de Freitas .................................................. 463

SHORT COMMUNICATIONS/COMUNICAÇÕES BREVES 1409

Pioneering transcatheter aortic valve Implant (Inovare®) via transfemoral Implante pioneiro de valva aórtica transcateter (Inovare®) por via transfemoral José Carlos Dorsa Vieira Pontes, João Jackson Duarte, Augusto Daige da Silva, Amaury Mont’Serrat Ávila Souza Dias, Ricardo Adala Benfatti, Neimar Gardenal, Amanda Ferreira Carli Benfatti, Jandir Ferreira Gomes Jr. .................................................. 469

1410

Comparison between multiplanar and rendering modes in the assessment of fetal atrioventricular valve areas by 3D/4D ultrasonography Comparação entre os modos multiplanar e renderizado na avaliação da área das valvas atrioventriculares fetais por meio da ultrassonografia 3D/4D Edward Araujo Júnior, Liliam Cristine Rolo, Christiane Simioni, Luciano Marcondes Machado Nardozza, Luciane Alves da Rocha, Wellington P. Martins, Antonio Fernandes Moron ...................................................................................................... 472

1411

Accessory mitral leaflet: an uncommon form of subaortic stenosis Folheto mitral acessório: uma causa incomum de estenose subaórtica Marcos Alves Pavione, José Teles de Mendonça, Ivan Sérgio Espínola Souza, Maria Amélia Fontes de Faria Russo ........... 477

CASE REPORT/RELATO DE CASO 1412

Aortic pseudoaneurysm as cause of superior vena cava syndrome: a case report Pseudoaneurisma de aorta como causa de síndrome da veia cava superior: relato de caso Katsuro Harada Júnior, Renato Garcia Lisboa Borges, Renata Kyioko Borges Harada ........................................................... 481

CLINICAL-SURGICAL CORRELATION/CORRELAÇÃO CLÍNICO-CIRÚRGICA 1413

Aneurysm of the left atrium in a child with patent ductus arteriosus and mitral valve prolapse Aneurisma de átrio esquerdo em criança com persistência do canal arterial e prolapso da valva mitral Danielle Lilia Dantas Tukamoto, Carlos Henrique De Marchi, Lilian Beani, Ulisses Alexandre Croti .................................... 485

MULTIMEDIA/MULTIMÍDIA 1414

Robotic assisted minimally invasive surgery for atrial septal defect correction Cirurgia minimamente invasiva robô assistida na correção da comunicação interatrial Robinson Poffo, Alex Luiz Celullare, Renato Bastos Pope, Alisson Parrilha Toschi ............................................................... 488

LETTERS/CARTAS 1415

Letter to the Editor Cartas ao Editor ....................................................................................................................................................................... 491

Reviewers BJCVS 27.3 .......................................................................................................................................................... 493

Impresso no Brasil Printed in Brazil

Projeto Gráfico: Heber Janes Ferreira

SOCIEDADE BRASILEIRA DE CIRURGIA CARDIOVASCULAR BRAZILIAN SOCIETY OF CARDIOVASCULAR SURGERY E-mail: revista@sbccv.org.br Sites: www.scielo.br/rbccv www.rbccv.org.br

Editorial

BJCVS on social networks

Domingo M. BRAILE*

DOI: 10.5935/1678-9741.20120059

he term “social network” is in vogue today, with the growing universality of such tool on the Internet and the expansion of its access either via PCs, laptops, iPhones, tablets and smartphones.

But far from being a novelty, the concept of “social network” has ancient roots. The embryo of the banking system, created by the Templar Order, and the so-called Guild, can be cited as examples of this type of structure, which brings together people with common interests.

In the case of the Internet, ClassMates.com, created in 1995, is considered the first social network. Accessed in the United States and Canada, the site’s purpose was to enable reunions between friends who studied together, either in high school or college. The service was paid, but managed to do successfully and is online today [1]. However, the growth and popularization occurred in the XXI century.

Currently, the great sensation among social networks is Facebook, created by Mark Zuckerberg in 2004, in collaboration with the Brazilian Eduardo Saverin, who has over 900 million users, according to The New York Times [2].

Scientific publications such as “Science”, have discovered this “niche” and now use social networks to promote their most important articles, obtaining, through shares and the option to “enjoy” the dissemination of scientific knowledge, which is of fundamental importance for every scientist who believes in the advancement of science, as information to be disseminated widely and can not be restricted to laboratory benches or closed groups, and should be quickly known by the whole society. It is the Translational Medicine, which seeks to transform the research for benefit of man and nature!

Over the years, Brazilian Journal of Cardiovascular Surgery (BJCVS), has sought to keep up with technological innovations, added to the print edition, has pioneered the electronic publishing and submission, followed by editing in e-Pub format (for iPads, iPhones and the like) and flip (which has the same formatting of the printed edition, and

T

can be read on PCs and notebooks), in the form of a print journal or PDF. Now moving us into the future, it is time to also be present in social networks.

So, since August BJCVS has its Facebook profile (http:/ /www.facebook.com/rbccv). Access can also be done through our website (www.rbccv.org.br) by clicking the Facebook icon at the top of the page. Remembering that, to access, the user must also have a profile. Despite our recent entry in these weeks, over 100 people have “enjoyed” the journal in Brazil and abroad, and the trend is that this number has a significant growth in the coming months. Soon, we will be providing articles and videos, and other information related to BJCVS, this and other Social Networks. We invite the esteemed readers “to enjoy” our page.

The Facebook profile is just another facet of the importance of BJCVS in the national and international scene.

The recent disclosure of the Impact Factor (1.239) positioned the journal as the sixth in the ranking of national scientific publications and the first of the surgical area. The Immediacy Index of 0.329 is the second highest among the top 20 Brazilian journals listed in ISI [3].

This growing number of citations is a reflection of hard work for the dissemination of BJCVS among cardiovascular surgeons and other health professionals, both in Brazil and abroad, in actions such as adoption of DOI, banners in Congress, expansion of the international reviewers and, fundamentally, the availability of content in English.

We have received more and more manuscripts, allowing better planning of issues and also enabling rejection of those whose content does not follow the minimum standards required by the Editorial Board. Our rejection rate is at around 40%, much higher than it was a few years ago. Moreover, the 60% who should be reviewed and subsequent published have had an increasing level, demonstrating the concern of the authors in developing well-grounded works, guided by the strictest scientific and ethical principles.

I

Fig. 1 - Indexes of RBCCV/BJCVS in Relative Database Citation Potential, Scopus

Fig. 2 - Access to sites RBCCV/BJCVS in August 2012

Thus, we can further raise the level of the articles that have been increasingly cited as our impact factor has been showing. To achieve index above 1.599, which is our goal for next year [3] and thus be classified by Capes as Qualis BI in Medicine I, II and III, we need more citations in journals II

indexed in Thomson Reuters (ISI), which can only be obtained with innovative studies of proven scientific relevance.

Although the ISI Impact Factor is the most widely used index for measuring the citations of scientific publications, there are other indicators. In the Relative Citation Database Potential, Scopus, another important database, the index of BJCVS referring to 2011 is 1.70 (Figure 1). This demonstrates that our journal has reached a solid status.

Translated into numbers, joining our site and the BJCVS website at Scielo (www.scielo.br/rbccv), we had, in August 2012, on average, more than 4,200 hits and nearly 382,000 pages viewed daily Internet users over 100 countries (Figure 2). Numbers are robust, giving us full conditions of dream flying higher.

In order to make this dream come into reality, we will continue working hard with the support of authors, reviewers, Associate Editors, Editorial Board Members and Senior Management of the Brazilian Society of

Cardiovascular Surgery (BSCCV). We know the challenges are great, but we are aware that we can overcome them.

Remember that since the volume 27.2, the circulation of the print edition of BJCVS was reduced only being distributed to educational institutions, databases, sponsors, counterparts journals and partners which answered the pool held in May. Access to full content and the free online edition, which includes the entire collection of BJCVS since its first issue in 1986, is available to all interested parties, whose number has increased very significantly.

We emphasize in this issue the interesting article: Proposal of a Single Scientometric Index, with an emphasis on balancing the positive participation of the first author: H-FAC Index, authored by peer Francisco Gregori Júnior, Moacir Fernandes de Godoy and Francisco Ferreira Gregori [4]. This study introduces a new way of knowing the impact of scientific production of researchers, in addition to provide important information about the different markers that show the position of authors in the international ranking.

The articles available for testing by the Continuing Medical Education (CME) in this issue are: “Factors associated with survival in patients undergoing cardiac transplantation using retrograde blood microcardioplegia” (p. 347), “Valve-in-valve transcatheter implant: a change of selection?” (p. 355), “Long-term

mortality in deep sternal infection after coronary artery bypass grafting” (p. 377) and “Influence of fresh frozen plasma as a trigger factor for kidney dysfunction in cardiovascular surgery” (p. 405).

My warmest regards,

Domingo M. Braile *Editor-in-Chief - RBCCV-BJCVS REFERENCES 1. http://www.techtudo.com.br/artigos/noticia/2012/07/historiadas-redes-sociais.html 2. http://www.nytimes.com/2012/05/15/technology/facebookneeds-to-turn-data-trove-into-investorgold.html?pagewanted=2&_r=1 3. Braile DM. Novo fator de Impacto: 1,239. Meta é passar de 1,5 em 2013. Rev Bras Cir Cardiovasc. 2012;27(2):I-II. 4. Gregori Júnior F, Godoy MF, Gregori FF. Proposta de um índice cientométrico individual, com ênfase na ponderação positiva da participação do primeiro autor: índice H-FAC. Rev Bras Cir Cardiovasc. 2012;27(3):370-6.

III

Editorial

The real world in diagnosis and treatment of acute coronary syndrome in Brazil O mundo real do diagnóstico e tratamento da síndrome coronariana aguda no Brasil

Eduardo Augusto Victor Rocha1

DOI: 10.5935/1678-9741.20120060

Chest pain, sweating, tingling in the arms, indigestion “upset stomach”, jaw pain, undefined discomfort or shortness of breath, these may be manifestations of an acute myocardial infarction (AMI), the second leading cause of death in Brazil. By having so many unspecific symptoms, it is difficult for a layman to identify them and seek specialized medical care in a timely manner.

The article by Bastos et al. [1] published in this issue of the BJCS, demonstrates that the population took 9 hours and 54 minutes on average to seek medical attention.

Patients treated in less time had a better prognosis. The emergency treatment decreases morbimortality and, consequently, the public costs for treating heart failure and other sequelae of AMI. The delay in recognizing the symptoms of AMI found in this article demonstrates the lack of knowledge of the population about the acute coronary syndrome (ACS). The work also demonstrates that the typical individual suffering AMI also has eating habits with high levels of fat.

Besides educating the population to identify the symptoms, the strategic distribution of chest pain units

1. Master in Surgery, Cardiovascular Surgeon at Vera Cruz University Hospital and São José University Hospital in Belo Horizonte, Minas Gerais, Brazil and Ibiapaba Hospital, Barbacena, MG, Brazil.

IV

(CPU) close to patients is essential. A professional qualification should be adequate to meet emergencies. Units equipped with necessary materials and equipment as well as trained personnel needs to be disseminated throughout the country. Careers should be attractive to keep specialist physicians experienced in the diagnosis of ACS in these units. We have shown in our practice the difficulty of physicians in emergency departments to make proper diagnosis of ACS in CPU. Sometimes we receive patients with acute aortic dissection (AAD) on use of antiplatelet agents due to the difficulty in differentiating acute aortic dissection from ACS. READ THE ORIGINALARTICLE ON PAGES 411-418 What can currently be noticed in our country are inexperienced, underpaid professionals working in poorly equipped services. This article demonstrates the reality of São José do Rio Preto, state of Sao Paulo, center of excellence in cardiovascular care, with a population at a

higher education level than the average in the country.

Possibly, we must have worse realities in Brazil. Taking into consideration this reality, there is an evident need for investment in education: the public and health professionals, so the ACS care service can be performed with excellence.

Medical societies should encourage continuing education. The careers of Emergency physicians need to be exciting to keep competent doctors working on the CPU. Basic education with an emphasis on health and media

campaigns can help alert people to seek medical attention in a timely manner. We need to educate the population about prevention and treatment of diseases!

REFERENCE 1. Bastos AS, Beccaria LM, Contrin LM, Cesarino CB. Tempo de chegada do paciente com infarto agudo do miocĂĄrdio em unidade de emergĂŞncia. Rev Bras Cir Cardiovasc.

2012;27(3):411-8.

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SOCIEDADE BRASILEIRA DE CIRURGIA CARDIOVASCULAR BRAZILIAN SOCIETY OF CARDIOVASCULAR SURGERY E-mail: revista@sbccv.org.br Sites: www.scielo.br/rbccv www.rbccv.org.br

ORIGINAL ARTICLE

Rev Bras Cir Cardiovasc 2012;27(3):347-354

Associated factors with survivals in patients undergoing orthotopic heart transplant using retrograde blood microcardioplegia Fatores associados à sobrevida em pacientes submetidos a transplante cardíaco utilizando microcardioplegia sanguínea retrógrada

Carlos Fernando Ramos Lavagnoli1, Elaine Soraya Barbosa de Oliveira Severino2, Karlos Alexandre de Souza Vilarinho3, Lindemberg da Mota Silveira Filho3, Pedro Paulo Martins de Oliveira4, Orlando Petrucci5, Reinaldo Wilson Vieira6, Domingo Marcolino Braile7

DOI: 10.5935/1678-9741.20120061

RBCCV 44205-1392

Abstract Background: Several techniques and cardioplegic solutions have been used for heart preservation during transplant procedures. Unfortunately, there is a lack of ideal method for myocardial preservation in the clinical practice.

The use of retrograde cardioplegia provides continuous infusion of cardioplegic solution during the graft implantation. This strategy may provide better initial recovery of the graft. The objective of this study is to describe the experience of a single center where all patients received the same solution for organ preservation and were subjected to continuous retrograde blood microcardioplegia during implantation of the graft and to evaluate factors associated to early and late mortality with this technique.

Methods: This is a retrospective, observational and descriptive study of a single center.

Results: During the study period were performed 35 heart transplants. Fifteen (42.9%) patients were in cardiogenic

shock. The probability of survival was 74.8±7.8%, 60.4±11.3% and 15.1±13.4% at 1 year, 5 years and 10 years of follow-up, respectively. The median survival time was 96.6 months.

Conclusion: The use of myocardial protection with retrograde cardioplegic solution may reduce the risks associated morbidity due to cold ischemia time during the heart transplant, and we suggest that this benefit may be even greater in cases of cold ischemia time longer ensuring protection to the myocardium.

1 – Specialist in heart surgery at Brazilian Society of Cardiovascular Surgery (Assistant Physician at HC UNICAMP), Campinas, SP, Brazil.

2 – PhD in Surgery at State University of Campinas (UNICAMP), Campinas, SP, Brazil.

3 - PhD in Surgery at State University of Campinas (UNICAMP), Campinas, SP, Brazil.

4 - PhD in Surgery at State University of Campinas (UNICAMP), Campinas, SP, Brazil; Assistant Professor at Medical Sciences Medical School, State University of Campinas, SP, Brazil.

5 – Postdoctorate, Cincinnati University, Assistant Professor at Medical Sciences Medica School, State University of Campinas, SP, Brazil.

6 – Full Professor at Medical Sciences Medica School, State University of Campinas, SP, Brazil.

7 – Full Professor at São José do Rio Preto Medical School and Medical Sciences Medical School, State University of Campinas, SP, Brazil.

Descriptors: Heart transplantation. Transplantation.

Heart arrest, induced. Myocardium. Follow-up studies.

Resumo Introdução: Uma grande variedade de técnicas e soluções é utilizada na preservação do coração durante o transplante, o que demonstra a falta de método ideal na prática clínica. A

This study was carried out at State University of Campinas, SP, Brazil.

Correspondence address: Carlos Fernando Ramos Lavagnoli. Caixa Postal 6111 – Campinas, SP, Brasil – Zip code 13083-970 E-mail: clavagnoli@gmail.com Article received on February 14th, 2012 Article accepted on July 17th, 2012

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Abbreviations, acronyms and symbols AV C ARF ACT

Stroke Renal failure requiring dialysis Activated clotting time

administração da cardioplegia de forma retrógrada propicia perfusão contínua, o que pode conferir melhor recuperação inicial do coração transplantado. O objetivo deste trabalho é descrever a experiência de um único centro onde todos os pacientes receberam a mesma solução de conservação de órgão e foram submetidos a microcardioplegia sanguínea retrógrada contínua durante o implante do enxerto e avaliar fatores de mortalidade precoce e tardia com a utilização desta técnica.

INTRODUCTION A variety of techniques and solutions are used in the preservation of the heart during transplantation, demonstrating the lack of ideal method in clinical practice [1].

In the present day, where the number of donors is not enough, in addition to the increase of high-risk recipients on the waiting list, every effort should be made towards better organ preservation. A better organ preservation leads to lower graft dysfunction and promotes better late outcomes after transplantation [2,3].

The use of retrograde blood cardioplegia has been described in several studies in the literature. There is no consensus whether this strategy promotes adequate myocardial protection [4]. Its use for the administration of blood cardioplegia during implantation is frequently reported in the literature. This strategy of cardioplegia administration allows for continuous perfusion of blood and added substrates, which can provide better initial recovery of the transplanted heart. [5] In research performed by Wheeldon et al. [6] in 1992, the use of retrograde blood cardioplegia was performed in less than 6% of the centers. The continuous retrograde blood microcardioplegia was introduced into our country

by Braile et al, proving to be safe and providing adequate myocardial protection in conventional cardiac surgery [7].

The aim of this study is to describe the experience of a single center where all patients received the same organ preservation solution and underwent retrograde continuous blood microcardioplegia during implantation of the graft and assessing factors of early and late mortality with the use of this technique.

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Métodos: Este é um estudo retrospectivo, observacional e descritivo, realizado em um único centro.

Resultados: No período do estudo, foram realizados 35 transplantes cardíacos, sendo que 15 (42,9%) pacientes encontravam-se em choque cardiogênico. A probabilidade de sobrevida foi 74,8±7,8%, 60,4±11,3% e 15,1±13,4% ao final de 1 ano, 5 anos e 10 anos de seguimento, respectivamente.

O tempo médio de sobrevida foi de 96,6 meses.

Conclusão: A utilização da solução cardioplégica para proteção de órgãos e a estratégia de iniciar a perfusão com microcardioplegia sanguínea retrógrada contínua forneceu proteção adequada.

Descritores: Transplante. Transplante de coração.

Sobrevida. Taxa de sobrevida. Parada cardíaca induzida.

METHODS Ethical characteristics, patient selection and demographics This is a prospective observational and descriptive study of a single center, with approval of the local Research Ethics Committee.

The study included patients undergoing orthotopic heart transplantation from 1998 to 2011. Patients undergoing cardiac transplantation were selected by a multidisciplinary team and the criteria followed were the same as described in the II Brazilian Consensus on Cardiac Transplantation of the Brazilian Society of Cardiology [8].

Graft explant technique After performing a median sternotomy, the pleura and pericardium were opened and the heart exposed for macroscopic assessment. When decided by capturing the organ, the vessels and veins of the heart were dissected to permit the explant securely, as already described in literature [8]. After aortic clamping, cardioplegic solution was injected into the aortic root.

In all cases, the solution at 4°C was used as described below (Braile Biomédica, São José do Rio Preto, Brazil): • in 1000 ml of sodium chloride 0.9%; • 50 mL of solution with the following composition: o75 mEq Potassium chloride; o 40 mEq magnesium chloride; o 30 mM monosodium glutamate; o 30 mM monosodium aspartate; During infusion of cardioplegia, the inferior vena cava and right superior pulmonary vein were sectioned. At the end of cardioplegia infusion, the cardiectomy was completed as described in literature [8].

Lavagnoli CFR, et al. - Associated factors with survivals in patients undergoing orthotopic heart transplant using retrograde blood microcardioplegia

Rev Bras Cir Cardiovasc 2012;27(3):347-54

The graft was placed in a 0.9% sodium chloride solution, with ice for shipping.

cardioplegia-inducing, solution was used for 3 minutes and then the maintenance solution was used throughout the procedure.

Perioperative and postoperative management Postoperatively, the same monitoring was used intraoperatively with blood pressure monitoring, continuous monitoring of cardiac output and central venous oxygen saturation. The administration of vasoactive drugs, dopamine, isoproterenol and sodium nitroprusside aimed heart rate above 100 beats per minute and the best possible cardiac output. Dobutamine was used in situations of inotropic support to optimize the right ventricular function when necessary. The epicardial pacemaker was used when necessary and during hospitalization in the intensive care unit. The withdrawal of ventilatory support was performed whenever possible. The removal of drains occurred generally within 48 hours and catheters were kept until inotropic support was no longer required. Transthoracic echocardiography was performed every 72 hours in the immediate postoperative period and routine laboratory tests in the first days after transplantation.

Surgical technique of implantation and intraoperative monitoring All patients underwent the same bicaval implantation technique, as described by Lower & Shumway modified Yacoub & Banner [9-11].

Prior to the beginning of the implant, we assessed the presence of patent foramen ovale and a purse-string suture in the coronary sinus ostium was performed to allow the infusion of retrograde blood cardioplegia. In summary form, the implant was initiated by anastomosis of the left atrium, using 3.0 polypropylene suture. Further, anastomoses were performed in the inferior vena cava and superior vena cava using 4.0 polypropylene suture. The pulmonary artery was then anastomosed in an end-to-end manner using 4.0 polypropylene suture. Finally, aortic anastomosis was performed using 4-0 polypropylene suture and a cannula was inserted into the aorta for infusion of antegrade blood cardioplegia in order to withdraw the cannula inserted into the coronary sinus ostium [12,13]. The intraoperative monitoring was performed using a catheter in the radial artery for continuously monitoring of blood pressure, pulmonary artery pressure, cardiac output and central venous oxygen saturation using the Swan Ganz catheter (Edwards Lifesciences, Irvine, USA).

Cardiopulmonary bypass technique The cannulation was performed in the ascending aorta and vena cava were cannulated individually. The flow cardiopulmonary bypass was 2.4 L.min-1.m2 with temperature maintained between 32 oC and 34 oC. The hematocrit during CPB was maintained between 25% and 28%. The membrane oxygenator was used in all cases (Braile BiomĂŠdica, SĂŁo JosĂŠ do Rio Preto, Brazil). Systemic heparinization was performed at a dose of 300 to 400 IU/kg heparin and activated clotting time (ACT) was maintained above 480 seconds. After unclamping, we routinely used dopamine, isoproterenol and sodium nitroprusside, to maintain heart rate above 100 beats per minute and the best possible cardiac output. All patients received a temporary pacemaker wires in the right atrium and ventricle.

Retrograde blood microcardioplegia technique The retrograde blood microcardioplegia system was described by Braile [7]. The system allows blood infusion continuously with cardioplegic solution in a concentration of 1%. Blood flow to the heart during implantation was maintained between 100 and 200 ml/min, not being interrupted for periods longer than 5 minutes. The interruption was made according to the judgment of the surgeon, according to the need for better visualization of the operative field. At the start of the infusion of

Late and hospital mortality All patients were followed after transplantation. Hospital mortality was defined as one that occurred within 30 days after surgery or that on which the patient was not discharged up to death after surgical implantation. Late mortality was defined as one that occurred 30 days after surgery or after discharge.

Early and late complications Complications were defined as early and late. The early complication occurred 30 days after surgery or until discharge of the patient, when this was over 30 days. The late complication was defined as that occurred 30 days after surgery or after discharge, when this was over 30 days.

Among the types of early complications, we observed: cerebrovascular accident (CVA), infection of the surgical incision, renal failure that required dialysis (ARF), duration of mechanical ventilation longer than 24 hours, low cardiac output syndrome and endocarditis. Late complications were recorded: CVA, IRA, graft failure, endocarditis, infections with severe sepsis, myocardial infarction, and neoplastic diseases.

Immunosuppression protocol Immunosuppression was standardized with prednisone, mycophenolate sodium and cyclosporine.

Immunosuppression was initiated preoperatively and continued postoperatively with 1 g of methylprednisolone daily for 3 days and mycophenolate sodium at a dose of 1440 mg daily. On the fifth day, if renal function was preserved, cyclosporin administration was initiated at a dose 349

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of 5 mg/kg per day, aiming the level of serum cyclosporine between 350-450 ng/mL. Prednisone was started on the fourth day at a dose of 1 mg/kg/day, and progressive reduction of 2.5 mg per day to achieve a dose of 0.2 mg/kg/ day which was then kept for 6 months after procedure.

were in cardiogenic shock in use of vasoactive drugs and/ or mechanical circulatory support.

The general data of this series are shown in Table 1.

Patients who died early had shorter time in waiting list for transplantation (P <0.01) (Table 2).

Early complications were observed in seven patients: stroke, infection of the surgical incision, IRA, duration of mechanical ventilation longer than 24 hours, low cardiac output syndrome and endocarditis. Late complications were found in 10 patients: stroke, IRA, graft failure, endocarditis, infections with severe sepsis, myocardial infarction, and neoplastic diseases.

Patients who had more complications after transplantation were more likely to death (P <0.01) and this was also observed in patients who experienced complications during late follow-up (P <0.01) (Table 3).

The functional class and echocardiographic variables of the graft are shown in Table 4. Only functional class was associated with higher odds of death in the early and late after transplantation (P <0.01).

The median time free from the first rejection after transplant was 17 days, range 7-390 days.

The probability of survival was 74.8 ± 7.8%, 60.4% ± 11.3 and 15.1 ± 13.4% at the end of 1 year, 5 years and 10 years of follow up, respectively (Figure 1A ). The median survival time was 96.6 months. The occurrence of rejection did not alter the probability of survival in these patients (HR 0.63 with 95% confidence interval: 0.14 to 2.87; P=0.44) (Figure 1B).

Biopsies protocol As recommended in the II Brazilian Consensus on Cardiac Transplantation [8], biopsies were performed weekly for the first month and monthly until one year.

Statistical Analysis Continuous variables were described as mean and standard deviation. The discrete variables are described as frequency.

For univariate analysis of factors associated with mortality in continuous variables we used the Student’ t test or Mann-Whitney test, when appropriate, and the chisquare test for discrete variables. The probability of survival was assessed by Kaplan-Meier analysis. The P value <0.05 was considered significant. SPSS version 19.0 for Macintosh was used (IBM, New York, United States).

RESULTS During the study period, 35 heart transplants were performed, with 60% of these performed in the last 18 months. All patients were in New York Heart Association functional class III or IV. Of the total, 15 (42.9%) patients

Table 1. Receptors demographic data.

Gender (F/M) Age (years) BMI Pulmonary vascular resistance (Wood units) Functional class Prioritized to transplant Waiting time in list (months) Preoperative diagnosis

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11 (31.4%) / 24 (68.6%) 44.5±10.1 25.7±4.0 3.5±1.9 8 in class III (22.9%), 27 in class IV (77.1%) 15 prioritized (42.9%) 20 non-prioritized (57.1%) 3.9±1.6 Valve disease 2 (5.9%) Chagas’disease 6 (17.6%) Ischemic 4 (11.8%) Viral 5 (14.7%) Post-partum 3 (8.8%) Idiopathic 15 (42.9%)

Lavagnoli CFR, et al. - Associated factors with survivals in patients undergoing orthotopic heart transplant using retrograde blood microcardioplegia

Table 2. Univariate analysis for early and late survival.

Variable Early death (n=4) CPB time (minutes) 99.5±23.7 Aortic clamping time (minutes) 70.5±11.1 Cold ischemia time (minutes) 52.5±55.1 Total ischemic time (minutes) 123.0±63.6 Surgery time (minutes) 303.7±52.2 Operative room time (minutes) 365.0±38.1 Distance from capture (Km) 51.0±60.1 Donor age (years) 32.2±14.7 Donor serum sodium (mEq/L) 153.3±21.4 Receptor/donor BMI relationship 1.1±0.13 Intraoperative bleeding (mL) 2450.0±2431.0 PVR (Wood) 4.0±2.1 Waiting time in list (months) 0.5±0.3 Prioritized to transplant 3

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Early survival (n=31) 97.9±18.0 66.2±11.0 64.2±33.0 130.4±36.2 267.3±51.6 342.5±52.1 73.9±61.1 29.3±9.0 155.5±16.8 1.0±0.2 643.2±391.1 3.5±2.0 4.3±5.3 12

P 0.87 0.47 0.54 0.73 0.19 0.41 0.48 0.57 0.84 0.52 0.23 0.57 <0.01 0.14

Late death (n=10) 97.6±22.1 60.1±13.4 38.9±32.2 99.8±37.3 280.5±48.5 346.7±50.0 34.8±46.0 26.1±8.5 164.7±19.8 1.0±0.0 785.7±452.5 3.2±2.8 2.6±2.2 4

Late survival (n=21) 98.1±16.6 68.5±9.3 75.0±27.4 143.5±27.3 261.7±53.0 340.7±54.1 92.6±59.4 30.8±9.0 154.2±16.4 1.0±0.2 576.7±356 3.6±1.8 5.2±6.2 8

P 0.93 0.08 0.01 0.01 0.36 0.78 0.01 0.17 0.32 0.84 0.25 0.67 0.09 0.76

CPB = cardiopulmonar by-pass, BMI: Body Mass Index, PVR = pulmonary vascular resistance

Table 3. Univariate analysis with hospitalization time and complications.

Variable early death early survival (n=4) (n=31) ICU time (days) 13.7±114.7 7.2±6.6 Time of hospital stay (days) 17.2±20.0 25.0±21.8 Early complications 4 3 Late complications __ __

P 0.44 0.50 <0.01 __

late death (n=9) 6.9±2.5 20.7±9.2 1 8

Late survival (n=21) 7.4±7.7 26.9±25.4 2 2

P 0.79 0.33 0.59 <0.01

ICU: intensive care unit

Table 4. Functional class and echocardiographic variables Variable Late death Late survival P (n=9) (n=21) EDLVD (mm)** 49.0±5.9 44.9±4.6 0.06 ESLVD (mm)** 32.9±6.7 26.6±3.8 0.03 EF (%)** 61.4±12.0 71.4±6.5 0.05 MI* 1 1 0.79 FC I 4 21 <0.01 FC II 1 0 FC III 1 0 FC IV 2 0 EDVD: End diastolic left ventricular diameter . ESLVD: End systolic left ventricular diameter. EF: ejection fraction. FC: Functional Class of heart failure of New York Heart Association.

MI: mitral insufficiency. (*): It was considered mitral failure that classified as moderate or severe. (**) Echocardiographic data regarding the graft. Average time of echocardiography after transplantation: 16.1 ± 31.25 months

DISCUSSION The aim of this study was to describe the experience of a single center where all patients underwent the same type of protective solution during cold ischemia and cardiectomy. We also assessed the factors of early and late mortality with the use of these techniques.

We demonstrated that 42.9% of our patients were in cardiogenic shock and 76.5% of them in functional class IV. We had no patients with low cardiac output syndrome in the immediate postoperative period and our early mortality was 11%. We observed that patients who died in the immediate period and during follow-up were less time on the waiting list for transplantation. Patients who had more complications during the immediate postoperative period and during follow-up also were at greater risk of dying. Our survival after 5 years was 60%.

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Fig. 1 - A: General Survival of patients undergoing transplantation after 10 years of follow-up. B: Survival of patients divided into patients without any rejection episode and patients who presented at least one episode of rejection

The importance of our findings is to demonstrate the safety of the myocardial protection technique during explant and type of cardioplegia during implantation of the graft in this series and clinical outcomes in short- and long-term follow-up. Our results are generally comparable to the literature [14,15].

A variety of techniques for the preservation of heart grafts used in clinical practice reflects the lack of an ideal method, new compounds are being added to the solutions, providing better preservation and increasing cold ischemia time [16].

Several solutions have been described for organ transplants [17-19]. The solution used by us was described

by Martins et al. [20]. It is routinely used in our department as cardioplegic solution in conventional cardiac surgery, and we are not aware of its use as a solution for preserving organs for transplant. Similarly, the cardioplegic solution enriched with histidine and tryptophan that was initially used in conventional cardiac surgery is now widely used as a protective solution for transplantation [19].

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Although several authors described the administration of retrograde cardioplegia promoting a non-uniform distribution of the solution to the myocardium, the clinical outcomes were satisfactory in this series using this technique [21,22].

Although the data shown here, the observation should be made with caution when it states that retrograde blood reperfusion of the heart during implantation confers reduced deleterious effects of ischemic injury, given the small number of observed population, low postoperative mortality and the low number of graft dysfunction after transplantation.

The use of myocardial protection with retrograde cardioplegic solution provided adequate protection to the myocardium and, therefore, we suggest that this benefit may also be extended to cases of longest cold ischemia [23]. Furthermore, the use of this method may make possible the organ procurement further afield and can thus increase the number of transplants that currently are declined by the distance from the center to capture [24].

The cold ischemia time was not a predictor of mortality, demonstrating that the solution used provided adequate protection and not compromising the operative or late outcomes. Obviously histological cuts or contractility variables were not assessed compared with other solutions, but this is beyond the scope of this study.

The cardiopulmonary bypass time was not a factor associated with early or late mortality. The same happened to aortic clamping. We should note that the duration of cardiopulmonary bypass is very similar to that described in the literature [14,15]. The clamping time was relatively short (average 66 minutes), which may have contributed to the outcome of this series.

There were differences in times of cold ischemia and total ischemia (P=0.01 and P=0.01, respectively), demonstrating that they are greater in groups with greater survival during the late follow-up. This finding suggests that patients with greater long-term survival showed ischemia time greater than the overall group at higher risk of late death, contrary to what one might anticipate. Our explanation for this fact is that the more severe receivers, prioritized or with pulmonary hypertension were assigned to receive a graft in the best conditions of proximity to the hospital with shortest ischemic time possible. So, again, we believe that the strategy of myocardial protection did not compromise our results, but the strategy of selecting donor/recipient.

We observed that patients who died early (30 days postoperatively) had less time on the waiting list when compared to those who survived in the early phase (0.5 Âą 0.3 vs. 4.3 Âą 5,3 months, P <0.01). This fact can be interpreted as follows: patients who were in worse clinical status preoperatively received marginal grafts or in non-ideal

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conditions. We note that the three early deaths were of patients who were in the prioritization list, under use of vasoactive drugs and/or intra-aortic balloon.

A similar trend was observed with respect to time on the waiting list for transplantation and the probability of late death. The late deaths were more frequent in the group that was less time on the waiting list. We believe that the explanation is similar to death during early because when patients were more severe the selection of the donor included marginal grafts.

The early complications observed were related to rejection or infection and, less frequently, to graft dysfunction. The hospital mortality was low (11%) and comparable to data from the national literature [14,15]. Late complications were related to infection not being detected cases of organ failure or allograft vasculopathy. These findings were also similar to those observed by Jung et al.

[25]. There were no patients with neoplastic disease in the late phase after transplantation.

Our overall late survival was 74% and 60% after 1 year and 5 years, respectively, rates similar to those described in the national literature [14,15].

We found no other demographic or clinical variables associated with early or late mortality in our study.

transplant recipients with pulmonary hypertension-retrospective analysis of 106 cases. Transplant Proc.

2010;42(9):3708-10.

Limitations and strengths of the study The limitations observed by us are referring to a retrospective study and the sample size, but it should be noted that 60% of the transplants were performed in the last 18 months. Therefore, follow-up time is still too small.

As a strength of this study, we can mention the use of the same methodology in myocardial protection for donor cardioctomy and during graft implantation in all patients.

In conclusion, we can say that the use of cardioplegic solution used as a solution for organ protection and the strategy starting perfusion with retrograde blood microcardioplegia provided adequate protection, because we observed no increased mortality with longer ischemic time. Further studies comparing different types of organ preservation solutions are still needed.

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ORIGINAL ARTICLE

Rev Bras Cir Cardiovasc 2012;27(3):355-61

Transcatheter aortic valve-in-valve implantation: a selection change?

Implante valve-in-valve transcateter em posição aórtica: uma mudança de seleção?

Diego Felipe Gaia1, Aline Couto2, João Roberto Breda3, Carolina Baeta Neves Duarte Ferreira4, Murilo Teixeira Macedo5, Marcus Vinicius Gimenes5, Enio Buffolo6,José Honório Palma7

DOI: 10.5935/1678-9741.20120062

RBCCV 44205-1393

Abstract Objective: Aortic valve replacement for bioprosthesis dysfunction is a procedure involving considerable risk. In some cases, mortality is high and may contraindicate the procedure. Minimally invasive transcatheter aortic “valvein-valve” implant appears to be an alternative, reducing morbidity and mortality. The objective is to evaluate aortic valve-in-valve procedure using Braile Inovare prosthesis.

Methods: The Braile Inovare prosthesis, transcatheter, expandable balloon, was used in 14 cases. Average EuroSCORE was 42.9%. All patients had double aortic bioprosthesis dysfunction. Procedures were performed in a surgical hybrid environment under echocardiographic and fluoroscopic guidance. Using left minithoracotomy prostheses were implanted through the ventricular apex under high-frequency ventricular pacing. Serial clinical and echocardiographic controls were performed. Follow-up ranged 1-30 months.

Results: Correct prosthetic deployment was obtained in all cases. There was no conversion. There was no operative

mortality. The 30-day mortality was 14.3% (two cases).

Ejection fraction increased significantly after the 7 th postoperative day. Aortic gradient significantly reduced. The residual aortic regurgitation was not present. There were no vascular complications or complete atrioventricular block.

Conclusion: The transcatheter “valve-in-valve” procedure for bioprosthesis dysfunction is safe with low morbidity. This possibility may change prosthesis choice during the first aortic valve replacement, favoring bioprostheses.

1. Federal University of São Paulo; PhD. Adjunct Professor of the Cardiovascular Surgery Discipline, São Paulo, SP, Brazil. Data Survey.

2. Federal University of São Paulo; Full Professor. Head of the Cardiovascular Surgery Discipline, São Paulo, SP, Brazil.

3. Medicine Student; Federal University of São Paulo, São Paulo, SP, Brazil. Data Survey.

4. PhD. Federal University of São Paulo, São Paulo, SP, Brazil.

Data Survey.

5. Federal University of São Paulo; Master’s Degree, São Paulo, SP, Brazil.

6. Federal University of São Paulo; Master’s Degree, São Paulo, SP, Brazil.

7. Federal University of São Paulo; Titular Professor, São Paulo, SP, Brazil.

Descriptors: Cardiopulmonary bypass. Aortic valve stenosis. Heart catheterization.

Resumo Introdução: A reoperação para substituição de biopróteses aórticas com disfunção é procedimento que envolve considerável risco. Em alguns casos, a mortalidade é elevada e pode contraindicar o procedimento. O implante minimamente invasivo “valve-in-valve” transcateter de valva

This study was carried out at Federal University of São Paulo.

Cardiovascular Surgery Discipline, São Paulo, SP, Brazil.

Correspondence address: Diego F. Gaia Rua Napoleão de Barros 715 – 3o andar – Cirurgia Cardiovascular – São Paulo, SP, Brasil – CEP 04038-000 E-mail: drgaia@terra.com.br Article received on May 8th, 2012 Article accepted on August 21st, 2012

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Gaia DF, et al. - Transcatheter aortic valve-in-valve implantation: a selection change?

Abbreviations, acronyms and symbols EuroScore STS Score

European System for Cardiac Operative Risk Evaluation Society of Thoracic Surgeons score

aórtica parece ser uma alternativa, reduzindo morbimortalidade. O objetivo deste estudo foi avaliar esses implantes utilizando a prótese Braile Inovare.

Métodos: A prótese Braile Inovare, transcateter, balão expansível foi utilizada em 14 casos. Euroscore médio foi de 42,9%. Todos os pacientes eram portadores de dupla disfunção de bioprótese aórtica. Os procedimentos foram realizados em ambiente cirúrgico híbrido, sob controle ecocardiográfico e fluoroscópico. Por meio de minitoracotomia esquerda, as próteses foram implantadas através do ápice ventricular, sob estimulação ventricular de alta frequência. Foram

INTRODUCTION The degenerative aortic valve calcification is considered the most common cause of aortic stenosis in developed countries, the most frequent indication for aortic valve replacement [1]. Standard treatment consists of valve replacement with a prosthetic device (biological or mechanical), with operative mortality around 4% [2]. Despite these results, there are limitations. Bioprostheses have limited durability, evolving along with structural degeneration along with the follow-up and the mechanics have risks as mechanical dysfunction and thrombosis. In the event of valve replacement (reoperation), the risk is higher than expected for the first replacement. Furthermore, some patients exhibit even higher mortality due to various morbidities. The combination of risk factors may determine the contraindications of the procedure in 30% of cases [3].

Recently, several groups have proposed the use of transcatheter therapy in order to reduce morbidity and mortality associated with conventional intervention when applied to high-risk individuals [4,5]. The improvement of the technique has allowed its application more secure and with progressive improvement of outcomes [6-8]. Recently, several groups have proposed the use of transcatheter technology in degenerated bioprostheses, a procedure called “valve-in-valve”, but the series is still limited and 356

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realizados controles clínicos e ecocardiográficos seriados.

O seguimento variou de 1 a 30 meses.

Resultados: A correta liberação protética foi possível em todos os casos. Não ocorreu conversão. Não houve mortalidade operatória. A mortalidade em 30 dias foi de 14,3% (dois casos). A fração de ejeção apresentou aumento significativo após o 7º pós-operatório e o gradiente aórtico apresentou redução significativa. A insuficiência aórtica residual não esteve presente. Não ocorreu complicação vascular periférica ou bloqueio atrioventricular total.

Conclusões: O implante “valve-in-valve” de valva aórtica transcateter em biopróteses com disfunção é um procedimento seguro e com morbimortalidade baixa. Essa possibilidade poderá alterar a indicação de seleção de prótese no procedimento inicial, favorecendo próteses biológicas.

Descritores: Ponte cardiopulmonar. Estenose da valva aórtica. Cateterismo cardíaco.

require confirmation as to its efficacy, safety and limitations [9].

In our environment, we developed a balloon-expandable prosthesis with encouraging initial results, including its use within degenerated bioprostheses [10,11].

The assessment of clinical results, safety and efficacy of the procedure performed with this new prosthesis within bioprosthesis dysfunction is the aim of this study.

METHODS Patient Selection Between June 2008 and December 2011, 14 patients from a single center underwent “valve-in-valve” transcatheter valve implantation being assessed prospectively, after signing an informed consent and Ethics Committee approval (CEP 1116/08).

Patients were selected by a multidisciplinary group. The selection of patients involved, in addition to multidisciplinary consultation and the inclusion and exclusion criteria, consideration of aspects such as high surgical risk, expectation, quality of life and assessment of biological fragility. The EuroSCORE and STS score risk scores were used in order to provide quantitative analysis of individual risk involved in the procedure.

Patients underwent clinical and laboratory tests,

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echocardiography, cineangiocoronariography and Doppler ultrasonography of iliac femoral and carotid systems.

The inclusion and exclusion criteria are listed in another publication [11]. Patients with bioprosthesis measuring 19 mm in diameter were excluded from the indication due to high risk of residual gradients, given the extreme reduction of the valve area.Demographic characteristics and comorbidities of the patients are listed in Tables 1 and 2.

The prostheses presenting dysfunction were composed of a variety of manufacturers: 3 Porcine Braile Biomédica, 3 Medtronic Hancock, 2 Biocor and 6 unmarked.

echocardiography (C Envisor HD, Philips Medical, The Netherlands). Complete equipment for cardiopulmonary bypass was available in stand-by in all cases (Braile Biomédica, São José do Rio Preto, SP, Brazil). In all cases transcatheter balloon-expandable bioprosthesis was used (Braile Biomedica, São José do Rio Preto, SP, Brazil) in sizes 20 to 24 mm in diameter as the inner diameter of the bioprosthesis dysfunction, considering a size of about 10%.

Intraoperative transesophageal echocardiographic controls were performed after valve implantation and hemodynamic stabilization of the patient, in order to check the correct functioning of the prosthetic valve, as well as hemodynamic characteristics. Angiographic controls were performed only in the event of doubt on echocardiogram in order to avoid the use of iodinated contrast.

After the procedure, all patients were maintained on dual antiplatelet therapy protocol using aspirin and clopidogrel.

Device and Procedure The “valve-in-valve’ aortic valve implantation was performed as previously described techniques [8,11]. All implants were performed with the aid of a surgical C-shaped arch (BV Pulsera, Philips Medical, The Netherlands), using radiolucent surgical table and dimensional Transesophageal

Table 1. Demographic characteristics and comorbidities.

Characteristic Age in years (mean) Females (n/%) Systemic Arterial Hypertension (n) Diabetes (n) Dyslipidemia (n) Glomerular filtration rate < 50 mL/min (n/%) Renal dialysis Restrictive / obstructive lung disease (n/%) Pulmonary arterial hypertension (n/%) Operated during hospitalization for decompensation (n/%) Atrial fibrillation (n/%) Functional type - NYHA (n/%) II III IV Comorbidities Coronary artery disease (n/%) Prior cardiovascular surgery (n/%) Peripheral arterial disease (n/%) Previous stroke (n/%) Cancer (n/%) Porcelain aorta (n/%) Biological fragility (Frailty) (n/%) Logistic Euroscore (%) (mean) STS score (%) (mean) Peak aortic gradient (mean±standard deviation) Mean aortic gradient (mean±standard deviation) Left ventricular ejection fraction (mean±standard deviation)

n=14 69.8 7/50 14/100 8/57.1 9/64.2 10/71.4 0 6/42.8 6/42.8 10/71.4 2/14.2 0 4/28.5 10/71.4 11/78.5 14/100 6/42.8 0/0 1/7.1 0/0 12/85.71 42.9 38.6 58.7±15.3 34.7±8.7 51.0±15.90

NYHA – New York Heart Association

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Table 2. Operative variables.

Variable Successful procedure (n/%) Conversion to conventional replacement (n/%) Defibrillation (n/%) Entry into cardiopulmonary bypass (excluding conversions) Contrast (mL) (mean) Fluoroscopy time (min) (mean) Procedure time (min) (mean±standard deviation)

Follow-up and outcomes Procedural success was defined as correct implant, satisfactory hemodynamic profile, the absence of significant valve or perivalvular leaks and no immediate major complications.

Patients were followed-up serially in the following postoperative: 1 day, 7 days, 30 days, 6 months, 12 months, 18 months and 24 months, with clinical and echocardiographic assessments.

The following outcomes were assessed: all-cause mortality (operative and 30 days post-discharge); major cardiovascular events, rehospitalization for prosthetic valve dysfunction or clinical deterioration; functional class; stroke, vascular complications, renal failure and bleeding.

Outcomes were assessed according to the recommendations of the Valve Academic Research Consortium [12].

Statistical Analysis Statistical analysis was performed using the Statistical Package for the Social Sciences (SPSS) version 11. The confidence level of 0.05 was used as significant. The comparison between the means used the Friedman test after verification of normal distribution of values. The mean and standard error were used to express the analysis, unless otherwise specified. The Kaplan-Meier curve was used for survival analysis of appropriate outcomes.

n=14 14/100 0 0 0 40 13.1 153.8±42.2

only the first four cases using contrast. No operative mortality occurred. There was no need to implant more than one valve in the same patient. Major vascular complication was not present. There was permanent pacemaker implantation. There was no severe or mild stroke. There was transient fall in platelet count in 5 cases.

We used the following device sizes: 2 of 20 mm, 7 of 22 mm and 5 of 24 mm.

The follow-up ranged from 1 to 33 months.

The surgical variables are listed in Table 2.

Mortality and hospital readmissions Two patients died within 30 days. During the follow-up after hospital discharge, there was three deaths: a case of cardiogenic shock with normal functioning prosthesis, a case of acute myocardial infarction in patients with coronary artery disease not previously treatable of surgical or percutaneous treatment and one by right heart failure and severe pulmonary hypertension in a patient with sickle cell anemia (prosthesis normofunctioning) (Figure 1).

RESULTS Procedure All cases were performed at the institution in a hybrid operating room. The successful valve implantation was performed in all cases. There were no conversions or prosthesis migrations.

The average time of implantation was 153.7 ± 42.1 minutes. The mean fluoroscopy time was 13.1 ± 7.5 minutes.

The quantity of contrast medium used was 40.0 ml, while 358

Fig. 1 - Kaplan Meyer. survival.

Evento = Event; Sobrevida =Survival; Tempo = Time

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Evolution of functional class The functional class improved significantly compared preoperatively at 1, 6 and 12 months (P <0.0001). A comparison of 1, 6 and 12 months did not show a statistically significant difference.

identification is also quite variable, and may lead to difficulty in precise location of the best implant site and the prosthetic ring. Some devices also require radiopaque markers, making the implant more dependent on the use of contrast media and transesophageal echocardiography. In case of lack of prior reliable information or unfavorable echocardiographic windows, CT may play an important role in measuring the annulus and collaborate to select the correct size of the device to be implanted.

Hospital mortality of the procedure is quite variable in the literature, but the groups, most often, are not comparable. The observed risk is lower than predicted by risk scores, although there are several questions about its validity [16].

The overall mortality compared to the expected risk scores demonstrates, again, that procedure is able to provide additional benefits in terms of survival. Survival after hospital discharge is also significant and causes of mortality in evolution were not related to the prosthetic device. Likewise, there was no structural degeneration of implanted prostheses, although this segment is still short for their definitive assessment [5].

The mean age of the study population is lower than that found in other studies, however, it is noteworthy that given the prevalence of rheumatic fever in the Brazilian population the average age in the realization of the first intervention is less. This fact explains why younger patients had already undergone multiple prior surgeries, raising their operative risk and justifying their inclusion in the study.

Complications occurred previously were not found in this sample [17]. Failure to proper occlusion of the left ventricular apex was not present. Some factors contribute to this finding, as the learning curve and the presence of adhesions that facilitate the support points and help the apical occlusion.

There were no cases of need for renal replacement therapy with hemodialysis, despite the presence of high glomerular filtration rate below 50%. Possibly, the low use of iodinated contrast collaborated to preserve renal function.

In all cases, we used the apical via to the transcatheter implant. The use of apical via, although more invasive, has additional advantages: 1. The prosthesis positioning is easier, given the proximity of the ventricular insertion point and aortic ring 2. The crossing of the failed prosthesis using guidewire and catheter insertion systems is easier, due to its ventricular aspect, due to the position of the valve leaflets; 3. The manipulation of the aortic arch is smaller, reducing the possibility of stroke 4. Navigation through the peripheral arterial system with the prosthesis is unnecessary, possibly contributing to the reduction of vascular complications.

Moreover, the presence of minithoracotomy certainly

Echocardiographic assessment The hemodynamic result assessed by echocardiography was satisfactory, with significant reduction of the peak gradient of 58.7 to 24.9 mmHg in the 1st postoperative day (P <0.001). The outcome showed that reducing the gradient was maintained in subsequent studies, with no statistically significant difference between the gradient obtained after implantation in the immediate postoperative period. The gradient also demonstrated a significant reduction of 34.7 mmHg to 12.8 mmHg on the first postoperative day (P <0.001).

The outcome showed the maintenance of that reduction.

The periprosthetic aortic insufficiency in the immediate postoperative period was not present.

Ventricular function measured by the left ventricular ejection fraction using the Simpson method showed statistically significant improvement from 51% to 55.6%, on the seventh day postoperatively (P <0.01), sustained during the follow-up.

The intraoperative variables are listed in Table 2.

DISCUSSION The valve replacement surgery is the procedure of choice in patients with aortic valve stenosis or prosthetic valve dysfunction. In the majority of the population, intervention has low risk and is able to promote functional improvement and increase the survival rate when compared to clinical treatment [2.13]. Nevertheless, a progressively larger portion of that population has necessitated the replacement of dysfunctional prosthesis and, consequently, higher operative risk [14].

Within this context, the possibility of less invasive intervention through transcatheter implantation has become an attractive alternative. Several centers have published results consistent with progressive reduction of complications and mortality in selected patients [7,9,11,15].

In the selected cases for implantation on a failed bioprosthesis, the results are even more encouraging, since the risks of complications and possible periprosthetic leaks are substantially smaller than the implant when compared to a native valve, making it even a more attractive alternative [9].

When compared to the implant on native prosthesis, it is noteworthy that prior identification of prosthesis dysfunction may be of extreme importance, since the same nominal diameters vary by manufacturer and landmarks chosen in the measurement. Moreover, radiological

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contributes to some degree of chest pain and transient deterioration of ventilatory capacity of these patients, contributing to the occurrence of comorbidities related to such dysfunction.

Structural valve deterioration still is a parameter difficult to assess and compare in the literature, due to the short follow-up period, and the small range of prostheses available. It is worrying that the fact of needing valve leaflets by balloon compression and expansion can theoretically cause premature structural deterioration thereof. [18] In our series, there was no deterioration of leaflets valve function during follow-up.

The atrioventricular block is a complication often described, and may reach one third of patients, especially with CoreValve [19]. Balloon-expandable prostheses, such as the Edwards Sapien and Inovare, had rates of need for permanent cardiac pacing at about 4.5% [7]. The presence of a prosthetic ring previously implanted probably protects the cardiac conduction system and, therefore further compression of complete atrioventricular block.

The need for conversion to conventional procedure, cardiopulmonary support and total valve replacement is reported as being around 3.5% [20]. In the present sample conversions did not occur. When compared to the implant on the native valve, it is expected an easier and safer procedure for many reasons: the suitable valve diameter is more easily found, since in most cases the diameter of the ring failed prosthesis is known or easily measured by imaging, such as computed tomography, allowing better selection of appropriate valve size and the presence of prosthetic dysfunction facilitates the identification of the correct position to release the device, reducing the possibility of implant embolization and also the risk of obstruction of the coronary ostia is also lower.

The assessment and echocardiographic follow-up of patients undergoing transcatheter therapy is of paramount importance when comparing different devices and conventional aortic valve replacement. The performance and durability of these new prostheses require constant assessment, because of the extensive differences in valve design, and its mode of implant fixation mechanism. There are no long-term data on these variables. The hemodynamic profile of these prostheses is superior to the traditional models, whether support-mounted or stentless. The absence of large supporting structures contributes to the superiority, providing significant gain in effective orifice.

Comparisons between the hemodynamic performance and evolution of improvement in ventricular function are markedly superior in patients undergoing transcatheter implantation compared to the usual intervention [21,22]. In “valve-in-valve” cases there is significant concern about the reduction in the effective valve orifice, this fact is noted by the lower transvalvular aortic gradient reduction when

compared to implant on native valves [11]. Thus, the implant within bioprosthesis with diameters less than 21 mm is questionable, as well as implantation of a second transcatheter valve. Ongoing and unpublished studies intend to clarify the theoretical limits of “valve-in-valve” implant.

The transvalvular gradients after implantation decreased compared with the preoperative period and remained low during follow-up, demonstrating a favorable hemodynamic profile of this device. This maintenance is similar to that found in other commercially available prostheses [22].

Ventricular function improves significantly early and during the follow-up. On the seventh postoperative day, we should observe a significant increase. The rapid improvement may partly explain the differences in mortality observed between conventional and transcatheter procedure. No use of cardiopulmonary bypass and aortic clamping under cardioplegic protection and the presence of a lower afterload generated by transcatheter prostheses are possible causes [21,22].

The study has limitations such as sample size and follow-up time. Identifying individuals with greater benefit with this strategy is only possible with larger numbers of patients and long-term observational period. The randomization facing medical treatment and open replacement may confirm the findings.

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CONCLUSION “Valve-in-valve” transcatheter treatment using the Inovare prosthesis shows results comparable to the literature using other prostheses, with the advantage of greater diversification in size and consequent lower gradients. It is able to provide benefits to cardiac structural and functional improvement. It is mandatory to further follow-up aiming at measuring benefits, complications and improving selection criteria.

The conventional intervention remains the gold standard for low risk patients, but this new strategy can be recommended for selected groups with contraindications to the traditional procedure.

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Inspiratory muscle training improves tidal volume and vital capacity after CABG surgery Treinamento muscular melhora o volume corrente e a capacidade vital no pós-operatório de revascularização do miocárdio

Gabriela Bertolini Matheus1, Desanka Dragosavac2, Patrícia Trevisan3, Cledycion Eloy da Costa4, Maurício Marson Lopes5, Gustavo Calado de Aguiar Ribeiro6

DOI: 10.5935/1678-9741.20120063

RBCCV 44205-1394

Abstract Objective: To evaluate lung function and respiratory muscle strength in the postoperative period and investigate the effect of inspiratory muscle training on measures of respiratory muscle performance in patients undergoing coronary artery bypass grafting.

Methods: A randomized study with 47 patients undergoing coronary artery bypass grafting with cardiopulmonary bypass. They were divided into study group (SG) 23 patients and control group (CG) 24 patients, mean age 61.83 ± 8.61 and 66.33 ± 10.20 years, EuroSCORE SG 0.71 ± 0.0018 and CG 0.76 ± 0.0029, respectively. The study group underwent physical therapy and inspiratory muscle training with threshold IMT® and CG underwent conventional physiotherapy. We compared the maximal respiratory pressures (MIP and MEP), tidal volume (TV), vital capacity (VC) and peak expiratory flow (peak flow)

preoperatively (Pre-OP), 1 st (PO1) and 3 rd (PO3) postoperative day.

Results: There was a significant reduction in all variables measured on PO1 compared to preoperative values in both groups, MIP (P <0.0001), MEP (P <0.0001), TV SG (P <0.0004) and CG (P <0.0001) and VC SG (P <0.0001) and CG (P <0.0001) and peak flow (P <0.0001). At PO3, SG presented higher value of VC, GE 1230.4 ± 477.86 ml vs. GC 919.17 ± 394.47 ml (P=0.0222) and TV SG 608.09 ± 178.24 ml vs. CG 506.96 ± 168.31 ml (P= 0.0490).

Conclusion: Patients undergoing cardiac surgery experience reduced ventilatory capacity and respiratory muscle strength after surgery. Muscle training was performed to retrieve TV and VC in the PO3, in the trained group.

1. Physiotherapist of the Coronary Unit of the Hospital e Maternidade Celso Pierro, Pontifical Catholic University of Campinas (PUC Campinas); Preceptor of Residence in Cardiofunctional Physiotherapy – PUC Campinas, Campinas, SP, Brazil.

2. PhD at Surgery Department of the Faculty of Medical Sciences at Unicamp (FCM Unicamp), Campinas, Brazil.

3. Resident Physiotherapist in Cardiofunctional Physiotherapy, PUC Campinas Hospital, Campinas, SP, Brazil.

4. Cardiac Surgeon, Camínas Cardiosurgical Clinics, Campinas, SP, Brazil.

5. PhD in surgery at FCM Unicamp, cardiologist, Campinas, SP, Brazil.

6. PhD in surgery at FCM Unicamp, cardiac surgeon, Campinas, SP, Brazil.

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Descriptors: Physical therapy modalities. Breathing exercises. Myocardial revascularization.

This study was carried out at Hospital e Maternidade Celso Pierro, Pontifical Catholic University of Campinas (PUC Campinas), Campinas, SP, Brazil.

Correspondence address: Gabriela Bertolini Matheus Rua Carapá, 40 – Campinas, SP, Brazil – Zip code 13098-330 E-mail: gbmatheus@uol.com.br Article received on April 10th, 2012 Article accepted on June 25th, 2012

Matheus GB, et al. - Inspiratory muscle training improves tidal volume and vital capacity after CABG surgery

Abbreviations, acronyms and abbreviations CG SG MIP MEP TV VC PO3 CPB IMT IMT PO1 Preop.

ANOVA

control group study group Maximal Inspiratory Pressure Maximal Expiratory pressure tidal volume vital capacity, peak flow, peak expiratory flow 3rd postoperative day cardiopulmonary bypass inspiratory muscle training Inspiratory Muscle Trainer 1st postoperative day preoperative Analysis of variance

Resumo Objetivo: Avaliar a função pulmonar e força da musculatura respiratória no período pós-operatório e verificar o efeito do treinamento muscular inspiratório sobre as medidas de desempenho da musculatura respiratória em pacientes submetidos à revascularização do miocárdio.

Métodos: Estudo randomizado, incluindo 47 pacientes submetidos à revascularização do miocárdio com circulação extracorpórea. Os pacientes foram divididos em grupo

INTRODUCTION Heart surgery can cause a number of complications, such as the postoperative pulmonary complications, with significant impact on morbidity and postoperative mortality and hospital spending.

The etiology is complex and multifactorial, involving physiological changes related to cardiopulmonary bypass (CPB), sternotomy mechanical changes, surgical manipulation, effects of anesthesia and mammary artery use, among other pre-, intra- and postoperative variables [1,2 ].

The patients who had undergone median sternotomy with mammary artery dissection and also presenting pleurotomy reduction in ventilatory variables, in addition, factors such as immobility in bed, pain and temporary dysfunction of the diaphragm contribute to the hypoxemia, and pulmonary dysfunction in the postoperative period [3,4].

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controle (GC), 24 pacientes, e grupo estudo (GE) 23 pacientes, com idade média de 66,33 ± 10,20 anos e 61,83 ± 8,61 anos, respectivamente. O GE foi submetido à fisioterapia convencional e ao treinamento muscular inspiratório com threshold® IMT e o GC à fisioterapia convencional. Foram comparadas as pressões respiratórias máximas (Pimáx e Pemáx), volume corrente (VC), capacidade vital (CV) e pico de fluxo expiratório (Peak Flow) no pré-operatório (Pré-OP), 1º e 3º dias de pós-operatório (PO1) e (PO3).

Resultados: Observou-se redução significativa em todas as variáveis mensuradas no PO1, quando comparadas ao préoperatório, nos dois grupos estudados, Pimáx (P<0,0001), Pemáx (P<0,0001), VC: GE (P<0,0004) e GC: (P< 0,0001) e CV GE: (P<0,0001) e GC: (P<0,0001) e peak flow (P<0,0001).

No PO3, o GE apresentou em comparação ao GC, maior valor de CV, GE 1230,4 ± 477,86 ml vs. GC 919,17 ± 394,47 ml (P= 0,0222) e VC GE 608,09 ± 178,24 ml vs. GC 506,96 ± 168,31 ml (P=0,0490).

Conclusão: Pacientes submetidos à cirurgia cardíaca sofrem redução da CV e da força muscular respiratória após a cirurgia. O treinamento muscular realizado foi eficaz em recuperar o VC e a CV no PO3, no grupo treinado.

Descritores: Modalidades de fisioterapia. Exercícios respiratórios. Revascularização miocárdica.

It is common to observe changes in lung mechanics, restrictive breathing pattern and shallow breathing postoperatively. The atelectasis is common and is associated with reduced lung capacity and respiratory muscle strength. Also pneumonias can occur with an incidence reported in the literature between 3% and 16% [5].

Given the presentation of pulmonary dysfunction associated with cardiac surgery and its possible repercussions, it is crucial more research about the resources available today to reverse this situation [6].

Respiratory therapy is an integral part in managing the care of cardiac patients, both in pre- and postoperatively, it contributes significantly to better prognosis, acting preoperatively (Pre-op) with techniques aimed at the preventing pulmonary complications, and postoperatively, with hygiene and pulmonary expansion maneuvers [7].

In view of the described above, this study aimed to assess the ventilatory capacity in postoperative patients 363

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undergoing CABG and compare the values of the performance measures of respiratory muscles through the maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), tidal volume (TV), vital capacity (VC) and peak expiratory flow between a group undergoing conventional physiotherapy, and another group undergoing respiratory muscle training with threshold® Inspiratory Muscle Trainer (IMT).

with three sets of 10 repetitions with 40% of MIP measured on fist postoperative day.

IMT Respironics® Threshold® is a device having a valve closed by positive pressure with a spring that produces linear load independent stream, and was used for the IMT. The IMT was performed daily during the first three postoperative days, with three sets of ten repetitions, twice a day. The load used was 40% of the MIP measured in PO1 and rhythm and pauses were determined for each patient.

We assessed MIP, MEP, TV, VC and peak expiratory flow (peak flow), in three stages, Preoperative, PO1 and 3rd postoperative day (PO3), after performing the last training.

All measures were explained and experienced by patients before the trial and considered the best of three attempts. The MIP was performed using manovacuometer from functional residual capacity and MEP from total lung capacity, with values close to each other, without perioral leak, and the highest value obtained was considered [9].

The TV was measured using spirometer through the minute volume and divides by respiratory rate measured within one minute, the VC was measured using spirometer, from total lung capacity, with a slow and prolonged expiration.

The airway permeability was assessed by measuring the peak flow achieved with maximum and fast expiratory effort maneuver, starting from a maximal inspiration. The recordings were made through the Peak Flow Meter (ASSESS ®) device, which provided the peak expiratory flow in liters per minute.

METHODS From November 2007 to October 2008, 199 heart surgeries were performed at Hospital e Maternidade Celso Pierro, and 122 patients underwent CABG. Of these, were excluded during preoperative those presenting arrhythmias, chronic obstructive pulmonary disease, identified by prior spirometry or under use of bronchodilators, patients using tridil, and those presenting anginal chest pain and patients with a body mass index greater than 30 kg/m2. We also excluded patients who had complications in the postoperative period, of whom did not allow the measurement of weights on first postoperative (PO1) day under use of intra-aortic balloon, emergency surgery, reoperations and patients undergoing procedures associated with revascularization.

The study was approved by the Research Ethics Committee of the State Campinas and Pontifical Catholic University of Campinas, under registration number 294/2005 and 857/07, according to the Declaration of Helsinki. All patients signed a written informed consent form. The research was recorded in CONEP under number 163.623.

They were randomized into two groups randomly 47 patients: 23 patients in the study group (SG) and 24 patients in the control group (CG), diagnosed with chronic coronary failure and undergoing elective CABG with cardiopulmonary bypass via median sternotomy.

The surgical risk stratification was performed using the EuroSCORE, SG 0.71 ± 0.0018 and CG 0.76 ± 0.0029 [8].

The anesthetic protocol and surgical technique, including the protocol for conduct of CPB were the same.

All patients underwent median sternotomy using internal mammary artery graft, complemented with saphenous vein grafts, as inclusion criteria, and had a drain on subxiphoid position and another inserted in the sixth intercostal space to drain the left pleura. Analgesia in the postoperative period was optimized and followed the standard protocol used at the hospital. The CG underwent physiotherapy protocol service, which consists of assessment and guidance in preoperative, pulmonary reexpansion with fractionated patterns, incentive spirometry, orthostatic and postoperative ambulation, twice a day. The experimental group underwent the same protocol and also the inspiratory muscle training (IMT) using threshold® IMT twice a day 364

Statistical Analysis To compare proportions, we used the chi-square test or Fisher exact test. In the comparison of continuous or sortable variables in a single time between two groups we used the Mann-Whitney test. To study the effect of time and groups in the assessed parameters analysis of variance (ANOVA) was used for repeated measures and contrast profile for evolution of time. Results were considered statistically significant when P <0.05.

RESULTS The groups were similar with respect to demographics and comorbidities (Tables 1 and 2).

There was no statistically significant difference between groups with respect to time of surgery [CG 4.76 ± 0.73 hours and SG 4.36 ± 0.80 hours (P = 0.119)] CPB [CG 72.42 ± 17, 77 minutes and SG 75.78 ± 23.08 minutes (P = 0.658)], and time on which patients remained on mechanical ventilation [CG 2.43 ± 2.51 hours and SG 1.75 ± 2.80 hours (P = 0.256)] after admission to the coronary care unit (Table 3).

We considered the respiratory complications regardless of the degree and intensity of involvement. For the

Matheus GB, et al. - Inspiratory muscle training improves tidal volume and vital capacity after CABG surgery

diagnosis the radiological report of the first three postoperative days was considered. In this study, there was no statistically significant difference between the groups when the presence of respiratory complications.

Regarding the presence of pleural effusion, 14 (60.87%) patients in the SG and eight (33.3%) in the CG showed that complication, found in chest radiography with opacification of the costophrenic angle, between PO1 and PO3. Laminar atelectasis was detected in nine (39.13%) of the patients in SG and 15 (62.5%) of CG. Lobar atelectasis was not observed in any patient of SG, and was observed in one (4.17%) of CG, and pneumonia in any patient of SG, and three (12.5%) of CG (Table 4).

The group undergoing respiratory training showed a significant difference in length of stay in the coronary care unit, but with no difference between groups in length of hospital stay (Table 5).

Table 1. Demographics of the studied population.

Variables SG= 23 CG= 24 P (%) (%) Age (years) mean + SD 61.83 ± 13.53 63.3 ± 10.20 0.4622 Gender Male 18 (78.2) 16 (66.67) 0.374 Female 5 (21.7) 8 (33.33) BMI >25 <30 kg/m2 2 (8.3%) 3 (13.0%) 0.6662 BMI: Body Mass Index

Table 2. Comorbidities of the studied population.

Comorbidities SG= 23 (%) CG= 24 (%) SAH 23 (100) 23 (95) Diabetes 12 (52.1) 14 (58.3) Smoking 09 (39.1) 11 (45.8) AMI 10 (43.4) 06 (25) Dyslipidemia 19 (82.6) 15 (62.5) Alcoholism 03 (13) 01 (4.1)

P 1,0 0.6711 0.6422 0.181 0.1234 0.347

CG = control group, SG = study group, BMI = body mass index, SAH = hypertension, MI = myocardial infarction

Table 3. Time of surgery, cardiopulmonary bypass and intubation of the studied groups.

Variables SG CG P Time of surgery (hours) 4.36±0.80 4.76±0.73 0.119 CPB time (min) 75.78±23.08 72.42±17.77 0.658 OTI (hours) 1.75±2.80 2.43±2.51 0.256 CG = control group, SG = study group, CPB = cardiopulmonary bypass, OTI = orotracheal intubation

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Table 4. Respiratory complications postoperatively.

Complications SG (%) CG (%) Pleural effusion 8 (33.3) 14 (60.87) BCP 3 (12.5) 0 Laminar atelectasis 15 (62.5) 9 (39.19) Lobar atelectasis 1 (4.17) 0

P 0.058 0.234 0.109 1.0

CG = control group, SG = study group, BCP = bronchopneumonia

Table 5. Admission to the coronary care unit and hospital of the studied groups.

Hospitalization(days) Mean SD Minimum Maximum P 2.0 1.08 0.9 5.3 0.0236 SG ICU 2.63 0.92 1.0 4.0 CG 6.2 2.02 3.0 12.0 0.4147 SG Hospital 6.77 2.95 2.0 12.0 CG

Maximal Respiratory Pressures When comparing the MIP in the 1st PO with Preoperative, a decrease in both groups was found, CG [60.21 ± 24.65 cmH2O vs. -85.71 ± 28.46 cmH2O] and SG [47.57 ± 18.54 cmH2O vs. -81.91 ± 24.81 cmH2O (P< 0.0001)].

In PO3 was observed significant recovery of MIP measures, but no return to preoperative values [GC -75.75 ± 25.00 cmH2O and GE -66.43 ± 21.79 cmH2O (P<0.0001)]. There was no significant difference between CG and SG (P = 0.1680). The evolution of the MIP values can be seen in Figure 1.

Comparing the MEP values in PO1 and Preoperative, there was significant reduction in both groups [CG 58.25 ± 27.96 cmH2O vs. 84.96 ± 31.51 cmH2O] and SG [61.04 ± 29.21 cmH2O vs. 94.70 ± 26.86 cmH2O (P< 0.0001)]. In PO3, there was an increase of measures [CG 70.04 ± 29.25 cmH2O and SG 78.39 ± 36.22 cmH2O (P<0.0001)], however, with no statistical difference between groups (P = 0.168 ). There was no return to preoperative values. The trend in the MEP values in the patients studied is shown in Figure 2.

Tidal Volume Measures (TV) Comparing the value of TV between PO1 and Preoperative, a decrease in both groups [CG 443.79 ± 195.10 vs. 756.38 ± 220.05 ml (P<0.0001)] and SG [475.17 ± 140.67 vs. 655.96 ± 244.42 ml (P=0.0004)]. In PO3, we observed a significant increase in the amount of TV in SG [608.09 ± 178.24 ml (P=0.0015)]. There were significant differences between CG and SG on the 3rd postoperative day (P=0.0490). The TV values in the studied patients are shown in Figure 3.

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Peak Expiratory Flow The peak flow value showed a significant reduction in PO1 when compared to preoperative [CG: 136.67 ± 71.18 L/m vs. 347.92 ± 150.51 L/m and SG: 154.13 ± 56.34 L/m vs.

350.65 ± 133.19 L/m (P<0.0001)], with no difference between groups (P=0.4750). In PO3, measures of CG 203.75 ± 83.55 L/m and SG 221.30 ± 100.87 L/m showed significant recovery, but did not return to the preoperative values.

The development of measures of peak flow is shown in Figure 5.

Fig. 1 - MIP. Evolution of the MIP measures in the groups studied

Vital Capacity (VC) Comparing the VC value between PO1 and Preoperative, there was a decrease in both groups, CG [731.25 ± 279.68 ml vs. 2425.0 ± 956.33 ml (P<0.0001)] and SG [790.00 ± 330.45 ml vs. 2537.0 ± 1067.9 ml (P<0.0001)]. In PO3, we observed recovery of measures in both groups, but more markedly in the group undergoing respiratory training [CG 919.17 ± 394.47 ml and SG 1230.4 ± 477.86 ml]. There were significant differences between CG and SG (P=0.0222) in PO3. The measures remained significant decreased with respect to preoperative value. The VC values of the studied patients are shown in Figure 4.

Fig. 2 - MEP. Evolution of MEP measures of the studied groups CG = control group, SG = study group

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Fig. 3 - Evolution of the tidal volume in both groups. Tidal volume CG = control group, SG = study group, TV = tidal volume

Fig. 4 - Performance of vital capacity in both groups CG = control group, SG = study group, VC = vital capacity

Matheus GB, et al. - Inspiratory muscle training improves tidal volume and vital capacity after CABG surgery

Fig. 5 - Evolution of the peak flow of the studied groups CG = control group, SG = study group, PF = peak expiratory flow

DISCUSSION Regarding the descriptive characteristics of the study population, the groups were similar in age, gender and weight. Several authors performed measurements of maximal respiratory pressures and the values published in the form of equations, used as reference for certain populations. Most of these authors relate the values of maximal respiratory pressures with age and gender [10].

In the present study, there was no significant difference between groups with respect to operative time, CPB and intubation. Surgery and anesthesia affect ventilatory function. Some authors observed an increase in lung density in areas dependent on both lungs after anesthesia, suggesting formation of areas of atelectasis [11]. According to Nardi et al. [12], CPB time greater than 60 minutes seems to have an inverse relationship with MIP values.

In this study there was no significant difference in relation to respiratory complications. Garcia & Costa [13] reported one or more types of pulmonary complications in the postoperative phase in 74% of patients, being 17% pleural effusion and 10% atelectasis.

Atelectasis is most frequently found in postoperative and radiological findings are key for the left lower lobe.

Atelectasis is related to deterioration in gas exchange, decreased lung volumes and functional residual capacity and lung compliance. It becomes relevant when it is persistent, is associated with hypoxemia, increased breathing work and other signs of stress [14].

Landymore & Howell [15] reported that patients who received internal mammary artery as a graft and underwent chest drainage showed a higher incidence of pleural

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effusion, atelectasis in the left lower lobe and elevation of the left hemidiaphragm. Moreover, three months after surgery these patients maintained loss of lung volume, areas of atelectasis and pleural effusion. In this study, all patients received internal thoracic artery graft, being that fact uniformed.

In this study, all variables, MIP, MEP, peak expiratory flow, TV and VC, presented a significant reduction in PO1 compared to preoperative.

A significant reduction in postoperative respiratory muscle performance is expected, as shown by lower values of MIP and MEP in both groups. The effects of cardiac surgery on muscle function, pain and the presence of chest tubes probably contribute to these findings. In the postoperative period, there is a reduction in lung volumes and capacities, and impaired respiratory function [12].

The reduction in the amount of peak expiratory flow indicates interference in respiratory function, by decreasing muscle strength and range of motion, secondary to surgical trauma [13]. Similar results were reported by Johnson et al.

[5] in patients during postoperative CABG. Also Nardi et al. [12] reported a significant reduction of approximately 50% for all variables (VC, MIP, MEP and peak expiratory flow) in the PO1 of heart surgery when compared with the preoperative period.

In this study, there were significant increases in all measured variables until the PO3 in both groups.

Despite the increase, there was no recovery of measures to preoperative values, except for the TV value in the trained group. This finding is in agreement with data shown by Silva et al. [16] who assessed the behavior of MIP, MEP and spirometry in a group of patients undergoing cardiac surgery and found significant reductions in lung volumes and flows and in maximal respiratory pressures in PO1.

There was a significant increase in respiratory muscle strength until hospital discharge, even without specific training, however, the measures remained below the values obtained in the preoperative [16].

In this study, although the inspiratory muscle training has not demonstrated effects on MIP and MEP until PO3, it was effective in increasing, significantly, ventilatory function, as demonstrated by the increase in the TV and VC values, the group who underwent training with.

Ferreira et al. [17] reported similar results after training with IMT速 threshold in preoperative. The patients showed a significant increase in forced vital capacity and maximum voluntary ventilation, but no difference in MIP and MEP was observed in the postoperative period.

The more frequent result of the change in lung volume in patients with muscle weakness is the fall in vital capacity.

Thus, it can be noted that the VC reflects the weakness of respiratory muscles and lungs static mechanical load. [18] Changes in pulmonary function in patients undergoing 367

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cardiac surgery with CPB are largely responsible for the morbidity of these patients. The atelectasis are the most common complications, caused by decreased functional residual capacity, changes on chest wall mechanics and lung tissue, by increasing airway resistance and the postoperative pain, among other factors [19].

In this study, the control group received no specific training on respiratory muscles, but were also oriented in the preoperative and underwent respiratory therapy after surgery, and were encouraged to get out of bed and ambulate early.

It is possible that these measures and exercises, even without load, have contributed to improving the variables in the control group.

Barros et al. [20] trained a group of patients with 40% of MIP, from PO1 until discharge, which occurred on the 7th postoperative day. The behavior of MIP, MEP, TV and peak expiratory flow, as in the present study, significantly declined, but returned to the values obtained in the preoperative at the time of hospital discharge.

Other studies have shown that the respiratory muscle training during preoperative is effective to increase respiratory muscle strength in patients undergoing cardiac surgery [17,21,22].

Leguisamo et al. [23] reported that patients oriented in the Preoperative are better prepared to collaborate with the needs of postoperative treatment. Understanding the aim of pre- and postoperative physiotherapy, the limitations resulting from the surgical process and the proposed physiotherapy technique may help in the recovery and thereby reduce the length of stay in hospital.

Although the effects of respiratory muscle training are well defined with regard to the benefits to the patient, some methodological issues remain controversial in relation to the load to be applied, number of repetitions and training period.

In this study, the positive benefit of inspiratory muscle training can be observed through the significant increase in tidal volume, in PO3, with return to preoperative value.

There was also a significant increase in TV in the control group, despite the variable remains below the value obtained in preoperative. This result reinforces the findings of other authors who applied muscle training for a longer period and obtained an increase in MIP and MEP. It is possible that by applying muscle training for a few more days, such a result could have been obtained.

Measuring and monitoring the function of the respiratory muscles through the MIP and MEP measurements in patients undergoing cardiac surgery is a simple and important for planning interventions that can bring clinical benefits such as reduced postoperative pulmonary complications.

In this context, it is suggested that further studies be

performed in order to investigate and better define the methodology for obtaining the positive benefits of respiratory muscle training described herein.

The limitations of this study are related to measures of MIP and MEP, TV, VC, and peak expiratory flow assessment.

These tests depend on the understanding and cooperation of participating individuals. Therefore, the technique can have a determinative positive effect on the outcome.

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CONCLUSION Patients undergoing CABG presented a significant reduction of the performance measures of respiratory muscles in PO1 when compared to baseline Preoperative.

The respiratory muscle training was effective in recovering the TV and VC in PO3 in the group undergoing training. There was no difference in the presence of pulmonary complications and length of hospital stay between groups.

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ORIGINAL ARTICLE

Rev Bras Cir Cardiovasc 2012;27(3):370-6

Proposal of an individual scientometric index with emphasis on ponderation of the effective contribution of the first author: h-fac índex Proposta de um índice cientométrico individual, com ênfase na ponderação positiva da participação do primeiro autor: índice h-fac

Francisco Gregori Júnior1, Moacir Fernandes de Godoy2, Francisco Ferreira Gregori3

DOI: 10.5935/1678-9741.20120064 Abstract In the individual assessment of a scientific performance, five scientometric indices have been used most: the h-index, the index g, the h-major index, the contemporary h-index and the normalized h-index. We propose an alternative index (“Index h-fac”), which considers positively the participation of the first author and that, by having a dynamic characteristic, continuously monitors his/her performance and is easily adaptable to particular or individual situations from different research groups.

Results from the geometric mean between the original hindex as proposed by Hirsh and a correction factor (“fac”, “first author commitment”) and, in turn, this value is divided by the mean interval (in years) of all studies. The index emphasizes two scores (X and Y). These scores X and Y were obtained by asking to all 83 cardiovascular surgeons from Southern Brazil (Paraná, Santa Catarina and Rio

1. Associate Professor. Head of the Discipline of Cardiac Surgery at Department of Surgical Clinics, Health Sciences Unit, State University of Londrina (UEL), Londrina, PR, Brazil. Creator, Writing and Discussion of the Study.

2. Adjunct Professor of the Cardiology and Cardiovascular Surgery Department at São José do Rio Preto Medical School (FAMERP), Adjunct Learning Professor at Famerp, São José do Rio Preto, São Paulo, SP, Brazil. Writing and Discussion of the study.

3. Mechanical Engineering Student, Technology Institute of Aeronautics (ITA), São José dos Campos, SP, Brazil. Technical Assistance and Discussion.

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RBCCV 44205-1395 Grande do Sul) and Specialists, how they realistically estimated, in percentage, their effective contribution in each published paper in which they appeared as first author. Of the total, 80 (96.4%) responded. The average obtained was 78.0% and on this basis, the X score was established as 0.75 and the score Y as 0.25. The new index also considers the total number of citations as first author and as co-author, the average number of coauthors per publication and the total number of papers published.

Theoretical examples are presented, discussing the main advantages of application. Serial evaluations in real world situations should be instituted to confirm the diagnostic and prognostic utility of this new index.

Descriptors: Authorship and co-authorship in scientific publications. Bibliometric indicators. Scientific publication indicators. Systems for evaluation of publications.

This study was carried out at Health Sciences Unit at State University of Londrina (UEL), Londrina, PR, Brazil.

Correspondence address: Moacir Fernandes de Godoy Rua Garabed Karabashian 570 – São José do Rio Preto, SP, Brasil – CEP 15070-600 E-mail: mf60204@gmail.com Article received on September 1st, 2012 Article accepted on September 28th, 2012

Gregori Júnior F, et al. - Proposal of an individual scientometric index with emphasis on ponderation of the effective contribution of the first author: h-fac índex

Abbreviations, acronyms and symbols AC

CoC h CoN PS AI X Y

Total citations generated by a scientific production in which the researcher is the first author Total citations generated by a scientific production in which the researcher is coauthor Original index, as proposed by Hirsh Average number of coauthors per study published Total number of studies published Average interval of time between the year of each publication and the current year Weighting score for participation as first author Weighting score for participation as coauthor

Resumo Na avaliação individual do desempenho científico, cinco índices cientométricos têm sido mais utilizados: o índice h, o índice g, o índice h-major, o índice h contemporâneo e o índice h normalizado. Propomos um índice alternativo (“Índice hfac”), que pondera positivamente a participação do primeiro autor e que, por ter característica dinâmica, monitora continuamente seu desempenho, sendo facilmente adaptável

INTRODUCTION The term Bibliometrics deals with the application of mathematical and statistical methods, books and other media, relating mainly to the management of libraries and documentation centers. [1] On the other hand, the term Scientometrics refers to the analysis of the quantitative aspects of generation, dissemination and use of scientific information. The scientific data of any primary scientometric research are represented by all authors, their studies, their bibliographies and citations they receive. [2] The individual scientific output has been, in recent years, assessed with the aid of various indices, all aiming at quantifying the academic merit of a particular researcher [3,4]. Among these indices, one of the most used is the “hindex” proposed by Jorge E. Hirsh, professor of physics at the University of California in 2005. According to Hirsh, a researcher has determined h index if h studies of total

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a situações particulares individuais ou de diferentes grupos de pesquisa. Resulta da média geométrica entre o índice h original, conforme proposto por Hirsh, e um fator de correção (“fac”; “first author commitment”), sendo essa média, por sua vez, dividida pelo intervalo médio (em anos), de todos os estudos. O índice dá ênfase a dois escores (X e Y). Esses escores X e Y foram obtidos perguntando-se a todos os 83 cirurgiões cardiovasculares da Região Sul do Brasil (Paraná, Santa Catarina e Rio Grande do Sul) com Título de Especialista, em quanto estimavam, percentualmente, de modo realista, sua efetiva contribuição em cada trabalho publicado no qual apareciam como primeiro autor. Do total, 80 (96,4%) responderam. A média obtida foi 78,0% e, com base nisso, estabeleceu-se para o escore X o valor de 0,75 e, consequentemente, o valor de 0,25 para o escore Y. São considerados também o número total de citações como primeiro autor e como coautor, a quantidade média de coautores por publicação e o número total de trabalhos publicados.

Apresentam-se exemplos teóricos discutindo-se as principais vantagens da aplicação. Avaliações seriadas e em situação de mundo real deverão ser instituídas visando confirmar a utilidade diagnóstica e prognóstica desse novo índice.

Descritores: Autoria e co-autoria na publicação científica.

Indicadores bibliométricos. Indicadores de produção científica. Sistemas de avaliação das publicações.

studies appearing in publications as author or co-author have been cited at least h times. For example: the h-index is 5 if the researcher has at least 5 publications with 5 citations each [5].

H-index is on a single number, incorporating both quantity (number of publications) and quality (citations or visibility), and therefore has an advantage over these indices separately and on other measures, such as “number of significant studies”, “number of citations of those most cited, etc. [6].

This is an index easily applicable and practical, but on the other hand, some distortions may reveal, for which reason has appeared in the literature to suggest other indices in order to minimize the problem.

H-index does not take into account the number of citations to a given article has above h index. It is a consequence of the definition of the h-index of which the top publications have at least h2 citations, but the current number may be much higher. Thus, if a particular author 371

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has an h-index of 20 is irrelevant if some of his most cited articles have 50, 100 or 500 citations.

Egghe [7] disagree on this point and believes that a measure to indicate the overall quality of a researcher should include the citation counts of the most cited articles proposing, therefore, the “g-index”. He defines the g-index as the highest number of publications that together received a total of citations equal to or greater than g2. According that definition he concluded that whenever the g index is equal to or greater than the h index because the h index does not take into account how many citation above h2 while in the g index it is considered. The author believes that this small modification would retain all the advantages of the h-index without increasing the difficulty of calculating and eliminating what he considered a disadvantage.

Apart from the actual amount of citations, other authors turn to the interaction between researchers and their impact on h-index. Usually, in the authorship of a scientific study can be found three situations: those who are the first author, those who are called corresponding authors and, finally, collaborators without a special role. It has been noted a progressive increase in situations where multiple authors are considered “first-author” given their relative contribution or the existence of more than one corresponding author, which can create internal conflicts between groups.

Hu et al. [6] concerned with the complexity found in the patterns of collaboration between researchers introduce an h-index based on the function performed by the investigator at each study, called h-major (“h-maj”), which takes into account only the articles in which the researcher played a very important or central role. They define the hmajor index of a researcher as having a “m” value if m is the number of publications that the researcher has with relevant contributions with m citations. For example, if a researcher has a original h-index of 20, but only in 8 of these 20 had involvement considered of great importance, then his hmajor index will be 8. It should be noted that the “g” index mentioned above is always equal to or greater than the original h-index, while the h-major index will always be equal or less than that index. They propose that the h-maj index be used as a supplemental index to the original h-index, especially in areas where it is common occurrence of multiple key authors or multiple corresponding authors.

Hu et al. [6] could not to objectively quantify what they call the relevant or central participation in performing scientific study and it is also not clear in related publications.

The h-index never regresses original value, since the number of citations never decreases, but this fact may constitute a drawback of the method, since there is no impact on the index in case of a break in productivity.

To solve this fact, it was proposed the contemporary hindex, which adds a score inversely related to the age of

each article cited. Sidiropoulos et al. [8] proposed a Sc(i) score for a specific item (i) based on the citation count according to the formula:

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Sci= γ.(AC – AP +1)– δ.(Ci) Since γ and δ are coefficients with fixed values set forth by proponents of this contemporary h-index as 4 and 1, respectively, CY is the current year, PY is the publication year of the article and Ci is the number of citations that the article received.

Thus, citations received by an article in the current year are considered with the factor 4, while citations of studies published for 4 years already have their weight factor reduced to just one, dropping rapidly to only 0.67 when the article cited enters its sixth year of publication [2,8]: Sci=4.(2012– 2012+1)–1.(Ci) = 4.(Ci) Sci=4.(2012– 2009+1)–1.(Ci) = 1.(Ci) Sci=4.(2012– 2007+1)–1.(Ci) = 0,67.(Ci) By this formulation, a particular researcher will have a hc contemporary h-index when hc of his Np studies published obtain a Sci ≥ hc score and the other (Np – hc) articles have a Sci<hc score, numerically exemplifying, a particular researcher will have a h contemporary index 5 when 5 of their articles published Sci obtain a Sci ≥ 5 score and the other (Np–5) articles have a Sci< 5.</h score.

The normalized h-index uses the feature to normalize the number of citations of each article dividing that number by the number of citations of authors of the article and, therefore, seeks to provide a better approximation of the single impact of each author [2].

The “e” index proposed by Zhang [9], differentiates researchers who have the same h index, counting also the surplus of citations, or that is, the impact of other publications that are not in those that comprised the h index.

The h individual indices try to reduce the effects of coauthorship (hi index) dividing the h index by the number of authors, trying to better assess the impact by author [10,11].

Finally, the rates of citation-weighted according the age of the manuscript (AWCR, AWCRpA and aW-index) relate the number of citations weighted with the age of the article, where the number of citations generated is divided by the age of article [12].

Thus, we see that no modification of the h-index weights, more concretely, the effective participation of the first author in the production of scientific study.

The aim of this study is to present a new index (“h-fac Index”), in which a correction factor is introduced in order to consider positively the participation of the first author usually responsible for the conception of the idea,

Gregori Júnior F, et al. - Proposal of an individual scientometric index with emphasis on ponderation of the effective contribution of the first author: h-fac índex

preparation methods and effective performa of the trial until the final conclusions.

METHODS The h-fac index would result from the geometric mean between the original h-index, as proposed by Hirsh, and a correction factor (“fac” from English “first author commitment”) and this mean, in turn, divided by the interval average time (in years) of all publications since the year of each publication to the current year.

The “fac” component would be the sum of the number of citations generated by a number of publications in which the researcher is the first author multiplied by a “X” score, which represents the appreciation by participation as an author on the study, plus the sum of number of citations in which the researcher is coauthor, multiplied by a “Y” score that represents the appreciation by participation as coauthor, divided by the total number of coauthors that comprise the scientific researcher, all divided by the total number of articles published (Equations 1 and 2):

Where: h = Original h-index, as proposed by Hirsh CA = Total citations generated by a scientific production in which the researcher is the first author CoC = Total citations generated by a scientific production in which the researcher is coauthor CoN = Average number of coauthors per study published PS = Total number of studies published X = Weighting score for participation as first author Y = Weighting score for participation as coauthor AI = Average interval of time between the year of each publication and the current year Square root of h. (Fac) = Geometric mean between the h-index and the fac-factor To get the “X” and “Y” scores, we performed a survey among cardiac surgeons in Southern Brazil (states of Paraná, Santa Catarina and Rio Grande do Sul) with Specialist by the Brazilian Society of Cardiovascular Surgery (hence who have published at least one scientific study). The questions were posed by electronic means for surgeons to quantify their effective participation in a study that is the first author, based on the following: A) 0-20% B) 30-40% C) 50-60 %, D) 70-80% E) 90-100%.

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RESULTS Of the total of 83 surgeons included in the study, 80 (96.4%) answered. The values distributed by the ranges of choice are shown in Table 1.

Table 1. Breakdown of responses indicating the quantification of effective participation in scientific study when placed in the position of first author, under the self-assessment of 83 cardiovascular surgeons in southern Brazil.

Option Range Answers % A 0-20 0 0 B 30-40 0 0 C 50-60 10 12.1 D 70-80 48 57.8 E 90-100 22 26.5 X Did not answer 3 3.6

The mean indicated value of 78.1% with a range of variation from 55% to 95%, with most of the options located in the range of 70 to 80% of participation, being then adopted as weighting score “X” for first author the value of 0.75 and thus the weighting score “Y” of 0.25 to participate as co-author. The final formulation for the “fac” was defined as follows (Equation 3):

The following is an example of how would be the h-fac index for two researchers with the same number of articles published by generating the same number of citations, with the same original Hirsch “h”index, with the same average number of coauthors by publication and with the same average time interval between the year of each publication and the current year (Table 2 and Figure 1).

Table 2. Indicators of researchers 1 and 2 Researchers 1 N Total of Articles [TA] 20 N of articles as author 15 N of articles as coauthor 5 N mean of coauthors [NCo] per article 5 N citations as author [CA] 90 (assuming 6 citations per article) N of citations as coauthor [CoC] 30 (assuming 6 citations per article) h-index 6 AI 9

Researchers 2 20 5 15 5 30 90 6 9

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DISCUSSION

Fig. 1 - Development of the calculations of h-index for researchers 1 and 2

Another example of the application of h-fac index would be to compare the productivity of academic researchers with two different h-indices taking into account the weighting factor described above (Table 3 and Figure 2).

Table 3. Indicators of researchers 3 and 4.

N Total of Articles [TA] N of articles as author N of articles as coauthor N mean of coauthors [NCo] per article N citations as author [CA]

N of citations as coauthor [CoC] h-index AI

Researcher 3 30 15 15

Researcher 4 20 5 15

5 3 60 (assuming 4 30 (assuming 6 citations per citations per article) article) 90 60 4 6 9 9

Fig 2 - Development of the calculations of h-index for researchers 3 and 4

The mean time intervals (Ti) were established as being equal to the two researchers, in order to observe that the influence of the score of the first author (“X”) on the final index only.

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In the analysis of a medical curriculum vitae, the production of full scientific studies and their publication is what draws the most attention. Initially, we highlight the articles published internationally, a showcase that generates greater disclosure for two main reasons: high possibility of penetration by the importance of the scientific journal and language, usually English, in which the study is published [13,14].

The real contribution of a researcher for the advancement of scientific knowledge can only be valued by the same number of citations he generates, because that is the most accurate indicator that the study was actually read and forwarded some information.

On the other hand, it seems unfair that, while generally having a predominance of activity of one of the authors of a particular study, all receive equal benefit with respect to citations. Hence, there is the proposal to use the most valuable and appropriate scores.

The “X” score: Evaluation of effective participation of the first author In our proposal, a prominent factor for determining the “X” score, which because it was found based on the evaluation of the real world and with practically all cardiovascular surgeons from the south of the country, it should translate the effective equity share of participation of the study’s first author. A noteworthy fact is that this score almost certainly represents a profile not only regional but national, extensive, to all Brazilian cardiovascular surgeons and perhaps worldwidely, precisely by the characteristic of performance and personality of surgeons.

Moreover, in activities related to Clinic or the Basic Chairs, this score quite possibly will be different, since the participation distribution is more equitable between the authors and coauthors.

It is quite possible that, for clinical studies, the “X” score occupies an intermediate position, and for basic research, is almost uniform the participation by all, with minimal predominance of the first author. Similar surveys performed in the present study with surgeons, extended to those two other areas, and will be important to confirm our prediction.

Anyway, once established this score for each area, the “fac”component, indicative of the degree of commitment of each individual researcher with published work, will be easily calculated and therefore the h-fac index, allowing both peer assess as well as a self-assessment of academic performance over time.

Referring to the theoretical examples above mentioned (“Researcher 1” and “Researcher 2”), it appears that those two very similar situations and with original h-index equal to six for both researchers, the h-fac indices are different, favoring widely the first author.

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The extra weight of the X score of first author appreciated his participation in the preparation of studies, since, in most cases, the first author is the founder and many others, also the main contributor in the collection, assessment, writing and final conclusions. The way to perform these values and how to weigh it properly, without a doubt, is the most difficult, but the model presented in this study appears to circumvent the problem.

We would add that the geometric mean of the h-index and the original fac distributes mathematically correct form the contributions of each component of the formula, strengthening the information contained in the h-fac index.

When comparing the researchers with different original h-index, our proposition also appears to assist in the matter.

As exemplified in the “Researcher 3” and “Researcher 4”, it is noted by those examples given that despite the “Researcher 3” having an original h-index lower than the “Researcher 4” at a ratio of 4 to 6 (0.67), his productive capacity in terms of effective contribution to the study, based on the weighting factor has improved (ratio 0.28/ 0.33 = 0.85).

In articles with a single author, the author’s score, of course, will be 1 and those with two authors, sometimes the first author is cited by alphabetical order, as they participate in a similar way in the design and performance of the study. In such cases, the factors may not be valid, however, it is not what happens in most cases. Additionally, it can always assign a differential score, as 0.5 for each, exceptionally for the publication in question.

As already mentioned above, the the “X” score may eventually receive a value not so different from the “Y” score when the team of researchers concerned the distribution of tasks in the production of the study is more equitable, as often happens in basic research area. However, whatever the score attributed to the first author, his weighting will be positive and always greater than that attributed to participation as co-author.

The h-fac index proposed has the following advantages: 1st. Pondering positively the commitment and participation of the first author (“X” score); 2nd. Pondering negatively the number of co-authors, inhibiting the introduction of “ghosts” co-authors (CoN); 3rd. Pondering positively the number of citations per volume of publications (AC + CoC); 4th. Pondering negatively the number of publications without relevance (PS); 5th. Pondering the authors positively with the lowest average time interval between the publication date and the current date, indicating that they stays productive; 6th. Including all the benefits of predecessors global indices (using all citations, making valuable the first author and meeting the contemporary) without appreciably increasing the difficulty of calculation, which can still be

easily implemented in conventional spreadsheets; 7th. Covering also the characteristics of adaptability to particular conditions and might serve as an informative performance of most individuals or research groups.

8th. Finally, being related to the average time interval (in years), of all publications, from the year of publication until the current year, gives a dynamic nature to the proposed index and making valuable the ongoing maintenance of the productive state, because with no entries of new publications the denominator will only increase tending to reduce the h-fac.

Therefore, the introduction of the h-fac index complementing the Hirsch”h” index may significantly collaborate, in our view, for a fairer assessment of the scientific productivity of a given author.

In medium-term, the formation of a database with realworld situations can provide important analysis of the predictive value of the combination of the correction factor proposed to the original h-index.

CONCLUSION The h-index fac, in view of its value attributes to the first author, using all the citations, dynamism and contemporaneity, may constitute a useful tool to assess scientific production of cardiovascular surgeons in southern Brazil with Specialist Title, and, most likely, could be adapted and extended for application to quantify the productivity of individual researchers from other areas of medical knowledge.

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ORIGINAL ARTICLE

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Long term mortality of deep sternal wound infection after coronary artery bypass surgery Mortalidade em longo prazo da infecção esternal profunda após cirurgia de revascularização do miocárdio

Aline Alexandra Iannoni de Moraes1, Cely Saad Abboud2, André Zeraik Limma Chammas1, Yara Santos Aguiar1, Lucas Cronemberger Mendes1, Jonatas Melo Neto1, Pedro Silvio Farsky3

DOI: 10.5935/1678-9741.20120065

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Abstract Background: Deep sternal wound infection and mediastinitis determine high in-hospital mortality.

International studies show that these patients are also at increased cardiovascular mortality risk in long-term followup. However, data are scarce and there is no national data.

Objectives: The aim of this study is to evaluate the mortality and incidence of cardiovascular events in longterm follow-up of patients suffering from deep sternal wound infection and mediastinitis.

Methods: Case-control study, matched by propensity score in a 1:1 proportion, in patients submitted to coronary artery bypass grafting between 2005 and 2008 at the Institute Dante Pazzanese of Cardiology (São Paulo, SP, Brazil). The primary outcome was death. As a secondary outcome, we analyzed the composite event of myocardial infarction, new revascularization, stroke or death.

Results: Of 1975 patients, 114 developed one of the infections. During the mean follow up of 3.6 years, deep

sternal wound infection and mediastinitis increased the risk of death by 8.26 (95% CI 1.88-36.29, P = 0.005) and the incidence of combined end point by 2.61 (95% CI 1.2-5.69, P = 0.015). The Kaplan-Meier curves for both outcomes demonstrated that the greatest risk occurs in the first six months, followed by a period of stabilization and further increase in the incidence of events after 4 years of hospital discharge. The similarity between the curves of primary and secondary outcomes may be consequent to the predominance of death on the combined cardiovascular events.

Conclusion: The presence of deep sternal wound infection or mediastinitis increased mortality in long-term follow-up in this sample of the Brazilian population according to the same pattern displayed by the developed countries.

1. Resident at Cardiology Institute Dante Pazzanese of Cardiology, São Paulo, SP, Brazil.

2. Master, Head of Medical Section of Hospital Commission Dante Pazzanese Institute of Cardiology, São Paulo, SP, Brazil.

3. Medical Doctor and Chief of Coronary Disease Institute Dante Pazzanese of Cardiology, São Paulo, SP, Brazil.

Correspondence address Aline Alexandra Iannoni de Moraes Av. Dr Dante Pazzanese, 500 – Vila Mariana – São Paulo, SP, Brasil – Zip code: 04012-909 E-mail: alineiannoni@gmail.com

Work carried out at Instituto Dante Pazzanese of Cardiology, São Paulo, SP, Brazil.

Article received on May 24th, 2012 Article accepted on August 21st, 2012

Descriptors: Mediastinitis. Mortality. Myocardial revascularization. Coronary artery bypass. Surgical wound infection.

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Abbreviations, Acronyms and Symbols AMI BMI CABG C VA DSWI EF ESRD ITA PAD MR

Acute myocardial infarction Body mass index Coronary artery bypass graft Cerebrovascular accident Deep sternal infection and mediastinitis Ejection fraction End-stage renal disease Internal thoracic artery Peripheral artery disease Myocardial revascularization

Resumo Introdução: A infecção esternal profunda e a mediastinite determinam elevada mortalidade intra-hospitalar. Estudos prévios demonstram que esses pacientes também apresentam maior mortalidade cardiovascular em longo prazo. No entanto, os dados são escassos para o Brasil.

Objetivo: O objetivo deste estudo é avaliar a mortalidade e a incidência de eventos cardiovasculares em longo prazo em pacientes acometidos de infecção esternal profunda e mediastinite.

Métodos: Estudo de caso-controle com pareamento 1:1 por meio de propensity score, em pacientes submetidos à cirurgia de revascularização do miocárdio entre 2005 e 2008,

INTRODUCTION Deep sternal wound infection and mediastinitis (DSWI) are serious postoperative complications in patients undergoing coronary artery bypass graft surgery (CABG) [1-4]. Patients suffering from DSWI have high morbidity and mortality, with the in-hospital deaths occurring in up to 20% of those subjects [5].

Studies show that the increased mortality is also observed in long-term follow-up [6]. The leading cause of death is cardiovascular disease, particularly acute myocardial infarction [6,7]. Compared with individuals who had no infection, patients suffering from DSWI have a 13% increased risk of cardiovascular death in 10 years following surgery [7].

These studies, however, enrolled a small sample of patients and possess methodological limitations, due in part to the low incidence of mediastinitis. In our setting, inhospital mortality varies between 23% [8] and 32% [9] in patients suffering from mediastinitis, but there are no data on long-term mortality of DSWI in the Brazilian population.

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no Instituto Dante Pazzanese de Cardiologia (São Paulo, SP, Brasil). O desfecho primário avaliado foi óbito. Como desfecho secundário, analisou-se o composto de infarto agudo do miocárdio, nova revascularização miocárdica, acidente vascular encefálico ou óbito.

Resultados: De 1975 pacientes avaliados, 114 desenvolveram infecção esternal profunda ou mediastinite.

Durante o seguimento médio de 3,6 anos, as infecções conferiram razão de risco de óbito de 8,26 (IC 95% 1,8836,29, P = 0,005), tendo sido a razão de risco de desfecho combinado de 2,61 (IC 95% 1,2-5,69, P = 0,015). A curva de Kaplan-Meier para ambos os desfechos demonstra que o maior risco ocorre nos primeiros 6 meses, seguindo-se um período de estabilização e novo aumento na incidência de eventos após 4 anos da alta hospitalar. A semelhança entre as curvas dos desfechos primário e secundário pode ser consequente à predominância do óbito sobre os demais eventos cardiovasculares.

Conclusão: A presença de infecção esternal profunda ou de mediastinite aumentou a mortalidade em longo prazo nesta amostra da população brasileira, de acordo com o mesmo padrão exibido nos países desenvolvidos.

Descritores: Mediastinite. Mortalidade. Revascularização miocárdica. Ponte de artéria coronária. Infecção da ferida operatória.

The aim of this study was to evaluate the long-term mortality of patients with deep sternal wound infection in a public service in Brazil. As a secondary objective, we evaluated the incidence of cardiovascular events in the same population.

METHODS Case-control study with prospective follow-up based on a database of 1975 patients undergoing CABG at our institution between 2005 and 2008. Cases were defined as patients who developed DSWI according to Centers for Disease Control and Prevention criteria [10]. In order to guarantee the comparability between groups, a propensity score analysis was performed.

Propensity score In observational studies, randomization to different treatments is not possible. Thus, the different characteristics of the populations can insert bias in the interpretation of results. Multivariate analysis is the most known technique

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to exclude the interference of the covariates on the results of a study. The disadvantage of this feature is that the number of variables analyzed is limited to the number of patients enrolled in the study. Thus, in studies of rare diseases, where there are few patients enrolled, multivariate analysis may not eliminate all the confounding factors. If the selection of the control group is made using the propensity score analysis, it is possible to select patients for the control group that have similar characteristics to the affected group disease. This guarantees the pairing of as many features as necessary to ensure adequate comparability between groups.

Controls were defined through a propensity score analysis in a 1:1 ratio, in accordance with the following characteristics: age, gender, body mass index (BMI), chronic kidney disease defined as creatinine clearance less than 30 ml/min/1.73m2, smoking, previous heart surgery,

acute myocardial infarction, prior stroke, diabetes mellitus, peripheral arterial disease, ejection fraction lower than 50% defined by ventriculography, number of diseased vessels, injury in the left main coronary artery and the use of bilateral internal thoracic artery bypass.

The notification of the infection was performed by the method of active surveillance for 30 days, by the Hospital Infection Control Service. Treatment included antibiotic therapy, drainage of collections, debridement of necrotic tissue and subsequent wound closure. The pectoralis major muscle flap was performed in accordance with the evaluation of the surgical team. The dehiscences were closed by bilateral pectoralis major muscle flap. The rotation of the rectus abdominis muscle flap or omentum and composed of breast tissue were used when necessary [11-13].

Outcome data were collected from medical records or telephone contact.

Table 1. Propensity score pairing for baseline characteristics.

Age Female sex BMI (kg/m2)

Controls n (%) 114 61.86 + 8.52 55 (48)

DSWI n (%) 144 62.5 + 8.57 59 (51.8)

26 (22.8)

28 (24.6)

45 (39.5)

42 (36.8)

36 (31.6)

36 (31.6)

7 (6.1)

8 (7)

74 (64.9)

76 (66.7)

42 (36.8)

33 (28.9)

29 (25.4)

27 (23.7)

2 (1.8) 16 (14) 60 (52.6) 2 (1.8)

4 13 62 3

61 (53.5)

60 (52.6)

13 (11.4)

21 (18.4)

5 (4.4) 43 (37.7) 21 (18.4)

16 (14) 41 (36) 24 (21.1)

P 0.56 0.59

< 25 25 to 30

0.97

31 to 40 > 40 Diabetes mellitus Tobacco smoking

0.3

Previous Current Stroke ESRD AMI Previous CABG Vessel disease extent

(3.5) (11.4) (54.4) (2.6)

Three-vessel Left main Bilateral ITA bypass EF < 50% PAD

0.78

0.68 0.55 0.79 NA

0.35

0.33 0.78 0.61

DSWI: deep sternal wound infection; ESRD: end-stage renal disease, AMI: acute myocardial infarction, CABG: coronary artery bypass graft, ITA: internal thoracic artery, EF: ejection fraction, PAD: Peripheral artery disease

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Outcomes Primary outcome was death from any cause. As a secondary outcome, we evaluated the combined event of acute myocardial infarction (AMI), new myocardial revascularization, cerebrovascular accident (CVA) and death.

Statistical analysis Analysis of event-free survival was performed by the Kaplan-Meier and the Cox models after exclusion of patients that presented cardiovascular event within 30 days of the surgery. Continuous variables were analyzed by Studentâ&#x20AC;&#x2122;s t test or Mann-Whitney test when necessary. We analyzed categorical variables using the X2 test or Fisherâ&#x20AC;&#x2122;s exact test.

The significance level was 5% and bilateral tests evaluate hypotheses. The software used was SPSS 19 and R 2.5.1 for Windows.

Ethical aspects This study followed the principles of the declaration of Helsinski and was approved by the local research ethics under the protocol number 1443.

RESULTS Of 1975 patients that underwent CABG, 114 developed DSWI, corresponding to an infection incidence of 5.77%.

The propensity score paired 114 patients not affected by wound infection in the control group, ensuring comparability of baseline characteristics, as described in Table 1. Both groups had increased cardiovascular risk.

The mean age was 62 years, there was a high prevalence of diabetes mellitus (65.8%), obesity (38.2%), smoking (57.5%), previous myocardial infarction (53.5%), triple vessel disease (53.1%) and 36.8% had ventricular dysfunction.

Mean follow-up was 3.6 years, counted from the hospital discharge. Minimum follow-up was 10 months and the maximum was 6 years and 3 months. Excluding the 11 deaths occurred during in-hospital period, the follow-up was complete for 95.1% of patients. Analysis was based on 204 individuals, 109 from the DSWI group and 95 from the control group. The propensity score was revalued after exclusion of those patients and its validity was reaffirmed.

The 3.6 year survival of patients suffering from infection was significantly lower in the control group, 86.3% versus 96.8%, respectively. Infection conferred an odds ratio for death of 8.26 (95% CI 1.88 - 36.29, P = 0.005). The KaplanMeier curve showed an increased mortality in the group suffering from infection during the first six months after discharge, following a period of stabilization, and further increase in death after a four years follow-up (Figure 1).

Event-free survival was 89.5% in the control group and 79.8% for patients who had infection. The AMI, stroke, 380

Fig. 1 - Kaplan-Meier curves for death. Mortality rates are higher in the group suffering from infection in the first 6 months and 4 years after discharge (P = 0.001)

revascularization or death risk was 2.61 times greater for this group when compared with controls (95% CI 1.2 - 5.69, P = 0.015) (Figure 2).

Among the combined endpoints, the most common was death. Stroke also had a high incidence, though not significant, with an odds ratio of 5.43 (95% CI 0.63-46.71, P = 0.12) (Table 2).

Fig. 2 - Kaplan-Meier curves for combined cardiovascular events.

There is a higher incidence of combined cardiovascular events in the group suffering from infection in the first 6 months and 4 years after discharge (P = 0.012)

Table 2. Results.

Control (n) AMI 3 MR 3 Stroke 1 Death 3 Composite 10

DSWI (n) 2 1 5 15 23

P 0.75 0.37 0.07 0.001 0.42

DSWI: deep sternal wound infection; AMI: acute myocardial infarction; MR: myocardial revascularization

Moraes AAI, et al. - Long term mortality of deep sternal wound infection after coronary artery bypass surgery

DISCUSSION In this case-control study, we selected 114 patients who developed deep sternal wound infection or mediastinitis after CABG and compared with 114 controls identified by a propensity score analysis. In the 3.6 years follow-up, we demonstrated higher mortality and incidence of combined cardiovascular events in the group affected by infection.

We emphasize the high cardiovascular risk presented by the study population. The prevalence of diabetes mellitus, usually around 40% in the population undergoing CABG at our institution [14], was 65.8% in the population of this study. Of the study population, 38.2% were obese, while this incidence is 23% of the usual population submitted to CABG at our institution [14]. These findings probably reflect the more complex clinical preoperative profile presented by patients at risk of developing mediastinitis.

We used the propensity score analysis in order to select the control group, which ensured comparability between the two groups regarding the long-term risk of cardiovascular events, as described in Table 1.

Our mean follow-up was 3.6 years, resembling that of Braxton et al. [6]. In our study, the survival rate of infection in the affected group was significantly lower, 86.3% versus 96.8%, with the odds ratio of death being 8.26 (95% CI 1.88 - 36.29, P = 0.005). The distribution of the death risk occurred in a bimodal fashion. There was an increased mortality in the DSWI group during the first 6 months, followed by a stabilization period and a new increase 4 years after discharge (Figure 1).

Infection also resulted in an increase of the composite outcome of AMI, stroke, new myocardial revascularization or death, with an odds ratio of 2.61 (95% CI 1.2 to 5.69, P = 0.015). Distribution of the combined event risk by the Kaplan-Meier method was similar to that observed for mortality (Figure 2). However, these findings probably reflect the fact that death was the most frequent cardiovascular event of the secondary outcome. The short follow-up period and the non-knowledge of the cause of death may justify the low incidence of the other components of the combined outcome.

Some hypotheses are suggested to explain the greater cardiovascular risk of patients suffering from mediastinitis.

The infectious process leads to a chronic inflammatory process that could accelerate atherogenesis and increase thrombogenicity, resulting in plaque instabilization [7,14].

Thus, the chronic inflammatory process could compromise graft patency and increase mortality and cardiovascular events years after CABG [7,15]. Information regarding the long-term patency of coronary artery grafts in patients who had DSWI is still scarce [16].

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Limitations We were unable to verify the cause of death of our patients, but none of them were violent.

The study was unicentric, so careful must be taken not to generalize the data for the Brazilian population.

The loss of follow-up for 4.9% of patients initially enrolled in the study is low, especially considering that our institution serves patients from all over Brazil.

CONCLUSIONS We conclude that the DSWI increased mortality in this Brazilian long-term analysis in a similar manner to the few data found in the literature. Since this was a single center study, studies in other institutions are needed before these findings can be generalized to the Brazilian population.

REFERENCES 1. Tiveron MG, Fiorelli AI, Mota EM, Mejia OAV, Brandão CMA, Dallan LAO, et al. Fatores de risco pré-operatórios para mediastinite após cirurgia cardíaca: análise de 2768 pacientes. Rev Bras Cir Cardiovasc. 2012;27(2):203-10.

2. Sá MPBO, Soares EF, Santos CA, Figueiredo OJ, Lima ROA, Escobar RR, et al. Fatores de risco para mediastinite após cirurgia de revascularização miocárdica. Rev Bras Cir Cardiovasc. 2011;26(1):27-35.

3. Magedanz EH, Bodanese LC, Guaragna JCVC, Albuquerque LC, Martins V, Minossi SD, et al. Elaboração de escore de risco para mediastinite pós-cirurgia de revascularização do miocárdio. Rev Bras Cir Cardiovasc. 2010;25(2):154-9.

4. Sá MPBO, Figueira ES, Santos CA, Figueiredo OJ, Lima ROA, Rueda FG, et al. Validação do MagedanzSCORE como preditor de mediastinite após cirurgia de revascularização miocárdica.

Rev Bras Cir Cardiovasc. 2011;26(3):386-92 5. Rahmanian PB, Adams DH, Castillo JG, Carpentier A, Filsoufi F. Predicting hospital mortality and analysis of long-term survival after major noncardiac complications in cardiac surgery patients. Ann Thorac Surg. 2010;90(4):1221-9.

6. Braxton JH, Marrin CA, McGrath PD, Morton JR, Norotsky M, Charlesworth DC, et al. 10-year follow-up of patients with and without mediastinitis. Semin Thorac Cardiovasc Surg.

2004;16(1):70-6.

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7. Risnes I, Abdelnoor M, Almdahl SM, Svennevig JL. Mediastinitis after coronary artery bypass grafting risk factors and long-term survival. Ann Thorac Surg. 2010;89(5):1502-9.

12. Sampaio DT, Alves JCR, Silva AF, Lobo Jr NC, Simões D, Faria W, et al Mediastinite em cirurgia cardíaca: tratamento com epíploon. Rev Bras Cir Cardiovasc. 2000;15(1):23-31.

8. Abboud CS, Wey SB, Baltar VT. Risk factors for mediastinitis after cardiac surgery. Ann Thorac Surg. 2004;77(2):676-83.

13. Brito JD, Assumpção CR, Murad H, Jazbik AP, Sá MP, Bastos ES, et al. One-stage management of infected sternotomy wounds using bilateral pectoralis major myocutaneous advancement flap. Rev Bras Cir Cardiovasc.

2009;24(1):58-63.

9. Sá MP, Silva DO, Lima EN, Lima EC, Silva FP, Rueda FG, et al. Postoperative mediastinitis in cardiovascular surgery postoperation. Analysis of 1038 consecutive surgeries. Rev Bras Cir Cardiovasc. 2010;25(1):19-24.

10. Garner JS, Jarvis WR, Emori TG, Horan TC, Hughes JM. CDC definitions for nosocomial infections, 1988. Am J Infect Control. 1988;16(3):128-40.

11. Anger J, Farsky PS, Amato VL, Abboud CS, Almeida AFSA, Arnoni RT, et al. Use of a flap composed of skin and breast tissue for repairing a recalcitrant wound resulting from dehiscence of sternotomy in cardiac surgery. Arq Bras Cardiol.

2004;83(6):43-5.

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14. Farsky PS, Graner H, Duccini P, Zandonadi EC, Amato VL, Anger J, et al. Risk factors for sternal wound infections and application of the STS score in coronary artery bypass graft surgery. Rev Bras Cir Cardiovasc. 2001;26(4):624-9.

15. Ross R. Atherosclerosis: an inflammatory disease. N Engl J Med. 1999;340(2):115-26.

16. Mansuroglu D, Omeroglu SN, Kaya E, Kirali K, Sismanoglu M, Mataraci I, et al. Does mediastinitis affect the graft patency?

J Card Surg 2005;20(3):208-11.

ORIGINAL ARTICLE

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Initial experience with minimally invasive cardiac operations Experiência inicial com operações cardíacas minimamente invasivas

Francisco Costa1, Guilherme Winter2, Andrea Dumsch de Aragon Ferreira3, Tadeu Augusto Fernandes2, Claudinei Collatusso3, Fernanda Tome Tremel4, Fabio Rocha Farias5, Daniele de Fátima Fornazari3

DOI: 10.5935/1678-9741.20120066 Abstract Background: Minimally invasive cardiovascular operations have been proposed as an alternative method to correct several cardiac congenital and acquired heart diseases, with the aim to reduce morbidity and mortality.

Objectives: Describe the two years initial experience with minimally invasive operations, with emphasis on technical aspects and the learning curve.

Methods: Between July 2009 and March 2012, 95 patients were operated using minimally invasive operations. Mean age was 55 ± 15 years and 53% were females. The operations performed were atrial septal defect closure (25), aortic valve replacement (32), mitral valve repair (23), mitral valve replacement (12), excision of atrial myxoma (2) and resection of subaortic membrane (1). The incision was a mini right thoracotomy in 87 cases and ministernotomy in 8.

Results: Early mortality was 4.2%. Mean size of the incision was 6.3 ±1.2 cm. Extension of the original thoracotomy was necessary in only one case. Two patients suffered a stroke, and the mean total blood loss was 470 ± 277 ml. There were no cases of incision infection and 67% the patients had no major morbidity.

1. Titular Professor of the Medicine Department at Pontifical University of Paraná (PUCPR); Cardiovascular Surgeon, Curitiba, PR, Brasil.

2. Resident Physician in Cardiovascular Surgery at PUCPR, Curitiba, PR, Brazil.

3. Cardiovascular Surgery at PUCPR, Curitiba, PR, Brazil.

4. Student at PUCPR, Curitiba, PR, Brazil.

5. Cardiologist at PUCPR, Curitiba, PR, Brazil.

This study was performed at Pontifical Catholic University of Paraná

RBCCV 44205-1397 Conclusions: Our initial results with minimally invasive operations demonstrated that it was safe and with good clinical results. Patient satisfaction is quite high. After the learning phase has been transversed, minimally invasive operations may be an excellent alternative for many patients with congenital and acquired diseases.

Descriptors: Mitral valve. Aortic valve. Surgical procedures, minimally invasive. Heart valve diseases. Heart valve prosthesis implantation.

Resumo Introdução: Operações cardíacas minimamente invasivas têm sido propostas como uma alternativa para a correção de diversas cardiopatias congênitas e adquiridas, com o intuito de reduzir a morbimortalidade.

Objetivos: Descrever a experiência inicial de dois anos com operações cardíacas minimamente invasivas, com ênfase nos aspectos técnicos e na curva de aprendizado.

Métodos: Entre julho de 2009 a março de 2012, 95 pacientes foram operados com técnicas minimamente invasivas. A média de idade foi de 55±15 anos e 53%

– PUCPR - Irmandade Santa Casa de Misericórdia de Curitiba, Cardiology and Nephrology Institute of Curitiba, Curitiba, PR, Brazil.

Correspondence address: Francisco Costa Rua Henrique Coelho Neto, 55 – Curitiba, PR Brasil – CEP 82200-120 E-mail: fcosta13@me.com Article received on April 25th, 2012 Article accepted on July 6st, 2012

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Abbreviations, acronyms and abbreviations C VA CPB ASD CO2 RICS TEE AMI STS ICU

Stroke Cardiopulmonary bypass Atrial septal defect Carbon dioxide Right intercostal space Intraoperative transesophageal echocardiography Acute myocardial infarction Society of Thoracic Surgery Intensive care unit

pacientes eram do sexo feminino. As operações foram fechamento de comunicação interatrial (25), substituição valvar aórtica (32), plastia mitral (23), substituição valvar mitral (12), ressecção de mixoma de átrio esquerdo (2) e ressecção de membrana subaórtica (1). A incisão consistiu de minitoracotomia lateral direita em 87 casos e de miniesternotomia em oito.

INTRODUCTION The median thoracotomy remains the most widely used incision for the realization of most cardiac sugeries.

Through it, we can have full access to the heart chambers and vessels, and perform all types of operations, including valve surgery, congenital heart diseases, tumor resection, aortic aneurysm and coronary artery bypass grafting.

However, the surgical trauma involved is large considering the size of the incision and the need for complete section of the sternum, and may lead to postoperative pain, relatively long time for functional recovery, besides the possibility of serious infections [1] .

Nowadays, with wide access to information through the Internet, there is increasing demand by patients in search of less aggressive procedures. Furthermore, interventional cardiology has offered alternative solutions for the treatment of coronary failure and various valve diseases and congenital heart disease. In this context, it is natural that cardiovascular surgery seek technological developments that allow for the less invasive surgical treatment [2,3].

Minimally invasive surgeries refer to a variety of infusion techniques and visualization, allowing to perform surgeries 384

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Resultados: A mortalidade imediata foi de 4,2%, e o tamanho médio da incisão foi de 6,3 ± 1,2 cm. A extensão da toracotomia só foi necessária em um caso. Dois pacientes apresentaram acidente vascular cerebral, e a quantidade total de sangramento foi de 470 ± 277 ml. Nenhum paciente teve infecção de ferida operatória, e 67% dos casos não apresentaram morbidade pós-operatória significativa.

Conclusões: Os resultados iniciais com operações minimamente invasivas demonstraram que elas podem ser realizadas de forma segura e com resultados iniciais satisfatórios. O índice de satisfação dos pacientes foi elevado.

Uma vez ultrapassada a curva de aprendizado, as operações minimamente invasivas podem ser uma excelente alternativa para muitos pacientes com cardiopatias valvares e congênitas.

Descritores: Valva mitral. Valva aórtica. Procedimentos cirúrgicos minimamente invasivos. Doenças das valvas cardíacas. Implante de prótese de valva cardíaca.

with smaller incisions [4-7]. From the early 1990s, several authors began to advocate the use of these techniques, which have become the preferred approach for repair and valve replacement in a few specialized centers [1]. In theory, the use of less invasive techniques would be associated with less postoperative pain, shorter hospital stay, faster return to daily activities, top cosmetic results and possibly reduced costs [1-3]. On the other hand, there is concern that limited access may be associated with more immediate risks and the use of inferior alternative surgical techniques, as in the case of complex repair of the mitral valve [8].

Moreover, there is sufficient number of randomized controlled studies that prove, unequivocally, the real advantages of minimally invasive surgeries when compared to conventional techniques [2,3].

From June 2009, we used in selected cases minimally invasive techniques, preferably with lateral minithoracotomy for the correction of mitral and aortic valve, closure of atrial septal defects (ASD) or myxoma resection.

This study aims to show immediate results, discuss any difficulties and the learning curve encountered with the application of these techniques and their applicability in more routine valve surgeries.

Costa F, et al. - Initial experience with minimally invasive cardiac operations

METHODS Patients Between July 2009 and March 2012, 95 patients underwent usrgery consecutively, using minimally invasive techniques. In this initial series, patient selection criteria included mitral and aortic valve disease in which the surgeon anticipate the use of conventional and routine techniques, such as the implantation of mechanical or bioprosthetic prostheses or non-comples mitral repair involving the posterior leaflet prolapse alone. Patients with complex mitral prolapse involving both valve leaflets or Barlow’s syndrome, as well as patients with severe aortic calcification of the ascending aorta. The surgeries were performed at the Santa Casa de Misericórdia de Curitiba and Institute of Neurology and Cardiology of Curitiba (Curitiba, PR, Brazil).

The patients’ ages ranged from 21 to 84 years (mean = 55 ± 15 years) and 45 were male and 50 were female. The most common diagnoses that led the surgery were the aortic valve, and mitral septal defect. Most patients were preoperatively in NYHA functional class II or III and 15% had atrial fibrillation associated. Detailed clinical characteristics of the patients are listed in Tables 1 and 2.

Table 1. Clinical characteristics of 95 patients who underwent the minimally invasive surgeries.

No. of patients 95 Age (mean ± SD) 55 ± 15 years (21-84) Gender Male 45 47% Female 50 53% Electrocardiogram Sinus 80 84% Atrial fibrillation 15 16% Functional class – NYHA Class I 12 12% Class II 44 47% Class III 29 31% Class IV 10 10% Comorbidities Dyslipidemia 32 34% Diabetes mellitus 11 11% Hypertension 64 67% Obesity 7 7% Renal 5 5% Smoking 14 14% Chronic obstructive pulmonary disease 5 5% Peripheral arterial occlusive disease 4 4% Previous stroke 3 3% SD = standard deviation. NYHA = New York Heart Association

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Table 2. Diagnostic data in 95 patients who underwent minimally invasive surgeries Affection n % Aortic 33 Aortic stenosis 25 75 Aortic failure 4 12 Duble aortic lesion 3 10 Subaortic membrane 1 3 Mitral 36 Mitral stenosis 7 19 Mitral failure 20 56 Double mitral lesion 8 22 Prosthesis failure 1 3 ASD 25 Ostium primum 1 4 Ostium secundum 21 84 Sinus venosus 3 12 Left atrial myxoma 2 100 Etiology Aortic Bicuspid aortic valve Calcific degeneration Aortic anuloectasia Rheumatic Congenital Mitral Rheumatic Myxomatous Dilated cardiomyopathy ASD Congenital Left atrial myxoma

n 33 3 24 1 4 1 36 22 13 1 25 25 2

% 9 72 3 13 3 61 36 3 100 100

ASD = atrial septal defects

Preoperative assessment All patients were assessed with clinical examination, electrocardiogram, chest X-ray and two-dimensional Doppler echocardiogram. In patients older than 40 years, coronary angiography was performed to exclude the presence of associated coronary artery.

Whenever possible, chest and abdomen contrast angiography was performed to study in detail the anatomic relationships of cardiac structures in relation to the thoracic cavity, as well as to assess the presence of atheromatous disease in the thoracic and abdominal aorta and iliac and femoral vessels. In younger patients, however, this assessment can be performed with peripheral vascular ultrasound.

In all cases the decision to perform minimally invasive procedure has been previously discussed with each patient individually.

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Surgical technique Despite the technical aspects have been improved throughout the experiment, and some variation due to the type of surgery to be performed, the general principles are similar in all cases.

Anesthesia was performed with conventional intubation, without making use of selective pulmonary ventilation.

Where available, we used intraoperative transesophageal echocardiography (TEE) to monitor the proper placement of arterial and venous cannulae during cardiopulmonary bypass (CPB), as well as to guide the surgeon in some specific moments of the surgery, such as during infusion cardioplegic solution, remove air from the cardiac chambers after CPB and assessment of ventricular function postoperatively.

In 89 patients, a 3 cm incision was performed in the inguinal region and the CPB was established by retrograde perfusion with cannulation under direct visualization of the femoral vessels. In the remaining patients, arterial cannulation was performed directly in the ascending aorta, and venous drainage performed by the right atrium or femoral vein puncture. CPB was used with moderate hypothermia at 32ºC, with the aid of vacuum to optimize

venous drainage. Myocardial protection was achieved using cold blood cardioplegia in 89 patients, and Custodiol® solution in six cases. The aortic clamping was performed using retractable clamp.

In 87 patients, surgical access was performed using side mini-thoracotomy (Figure 1), and 8 cases using ministernotomy. In mitral patients or for closing ASDs, the incision was performed on the 4th right intercostal space (RICS), in the inframammary region, located between the anterior and middle axillary lines. As for the aortic patients, the minithoracotomy was anterior, intercostal, at 2nd or 3rd RICS, performing the ligation of right internal thoracic artery and usually with temporary detachment of the condrocostal junction of the inferior or superior rib to facilitate exposure of the aortic root. In all cases, we used a chest auxiliary contraincision, 1 cm long, which were passed a left ventricular drainage cannula, a catheter for continuous CO2 insufflation into the pleural cavity, in addition to some points of pericardium exposure. At the end of the procedure, this small incision is used for the passage of the chest tube.

The surgical technique for valve replacement or repair surgeries, closure of ASDs or resection of tumors were similar to those employed in conventional surgeries.

Postoperative assessment We assessed the results in the immediate postoperative period until the time of hospital discharge. Specifically, we study the immediate mortality, defined as any death within 30 postoperative days or before hospital discharge, and postoperative complications, including the need for reoperations, total amount of bleeding and need for blood transfusion, length of stay in intensive care unit (ICU) and hospital stay length.

RESULTS

Fig. 1 – Surgical access by lateral minithoracotomy

386

Our initial series with minimally invasive surgeries involved the implementation of correction of ASD (n=24), aortic valve replacement (n=33), mitral valve replacement (n=12), mitral valve repair (n=24) resection left atrial myxoma (n=2) and subaortic membrane resection (n=1). The details of the surgeries performed are listed in Table 3.

The aortic clamping time ranged from 18 to 117 min (mean 60 ± 25 min) and total CPB time ranged from 50 to 180 min (mean=96 ± 34 min). In most patients (n=87), surgeries were performed using side minithoracotomies, whose extension ranged from 4 to 10 cm (6.3 ± 1.2 cm).

Hospital mortality was of four (4.2%) cases. The causes of death were sepsis with multiple organ failure in two aortic elderly patients, low output syndrome in a patient with mitral regurgitation by dilated cardiomyopathy and mesenteric thrombosis in the latter case (Table 4).

Costa F, et al. - Initial experience with minimally invasive cardiac operations

Table 3. Operative data No. of patients Surgery performed Atrial septal defect Continuous suture Bovine pericardium patch Atrial myxoma Mitral repair Bovine pericardium ring Gregori's ring Carpentier's ring Commissurotomy Commissurotomy + bovine pericardium ring Quadrantectomy + bovine pericardium ring Mitral repair + ASD Commissurotomy + bovine pericardial patch Mitral valve repair Biological prosthesis Metalic prosthesis Aortic valve replacement Biological prosthesis Subaortic membrane Incision site 2nd right intercostal space 3rd right intercostal space 4th right intercostal space 5th right intercostal space Ministernotomy Incision size Type cannulation Aorta and right atrium Aorta and femoral vein Artery and femoral vein Artery and femoral vein, internal jugular vein Type of myocardial protection Antegrade cold blood Custodiol Retrograde cold blood Aortic clamping time (mean ± SD) Time of DPB (mean ± SD)

95 24 4 20 2 23 6 1 1 4 2 14 1 1 12 11 1 32 32 1

16% 84% 100% 27% 4% 4% 17% 8% 60% 100% 91% 9% 100% 100%

13 14% 24 26% 42 44% 8 8% 8 8% 6.34 ± 1.2 cm 5 1 86 3

5% 1% 91% 3%

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In the intraoperative period, we had three cases with lesions in cardiac structures requiring additional correction.

During weaning from CPB, a patient presented bleeding in the pericardial cavity, which forced us to enlarge the incision with transverse section of the sternum and extending of the thoracotomy up the left side of the chest, to correct traumatic bleeding in the left atrium, with good evolution. Two patients had mitral perforations in the right ventricle, one caused by the tip of the venous cannula and another by electrode of previously implanted pacemaker.

In both cases, the lesions occurred during retraction of the left atrium, and were readily identified before discontinuing CPB, and could be corrected successfully without need to extend minithoracotomy.

Among the common postoperative morbidities, we had the low output syndrome in 15% of cases and occurrence of paroxysmal atrial fibrillation in 14% of patients. In 67% of cases, there were no complications. In no patient wound infection was found. Despite not having an objective assessment of postoperative pain, patients subjectively reported only discomfort and pain in the chest considered as mild and bearable. The degree of satisfaction with the end cosmetic results are invariably high (Figure 2). Among the serious complications, two patients had cerebrovascular accident (CVA), of which one was transient and with complete reversal and the second patient presented sequelae due to extensive ischemic lesion in the left temporal lobe. Severe respiratory failure requiring tracheostomy occurred in 1 patient, and transient renal insufficiency was detected in six patients, however, without the need for dialysis in any of them (Table 5).

5% 92% 1% 7% 91% 1% 60.5 ± 25.4 min 96.4 ± 34.2 min

ASD = atrial septal defect. SD = standard deviation

Table 4. Immediate mortality in 95 patients who underwent minimally invasive surgeries Mortality 4 (4.2%) No. of deaths Deaths in the immediate postoperative Aortic valve replacement 2 Mitral valve replacement 1 Mitral repair 1 Causes of death Sepsis 2 Acute abdomen 1 Low output syndrome 1

Fig. 2 - Patient demonstrates satisfaction with end cosmetic results

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Table 5. Operative and postoperative morbidity in 95 patients undergoing minimally invasive surgeries.

No. of patients 95 Operative morbidity Need for conversion to conventional thoracotomy 1 1% Blood transfusion 74 77% Number of bags transfused (mean ± SD) 1.65 ± 1.62 Drains bleeding (mean ± SD) 470 ± 277 ml Days of hospitalization in ICU (mean ± SD) 2.8 ± 1.7 Days of hospitalization (mean ± SD) 8.7 ± 4.5 Postoperative morbidity New Atrial fibrillation 13 14% Low output syndrome 14 15% Intra-aortic balloon 4 4% Reoperation for bleeding 2 2% Respiratory failure 2 2% Tracheostomy 1 1% Pneumonia 5 5% Renal failure 6 6% AMI 2 2% CVA 2 2% Acute abdomen 1 1% Surgical site infection 0 0% No complication 64 67%

that make these surgeries more routine [1,2,9]. In our country, that number should be even lower, given the small number of publications on minimally invasive valve surgery, and with relatively small case series [10-13]. Among the major experiments, Poffo et al. [10] reported a case series of 102 patients who underwent surgery between 2006 and 2008, and more recently. Junior Fortunato et al. [12] reported the results of 136 patients who underwent surgery over 6 years.

The minimally invasive surgeries are performed in order to reduce operative trauma and possibly reduce the risk of morbidity and mortality. However, the results currently available do not prove unequivocally, objective benefits that justify the wider application of these techniques [14,15].

More recently, however, some studies suggest decreased mortality in some specific subgroups of patients, such as in mitral reoperations, obese and aortic or elderly [16-19].

The results of our initial series with minimally invasive surgeries confirm the observations of other authors that, in selected cases, plasty or valve replacement surgeries, correction of some congenital heart disease and atrial myxoma resection can be performed safely and with mortality rates comparable to those obtained through conventional sternotomy [3,11]. Despite not having a control group and this study not being comparative, no immediate deaths in this series can be attributed to complications related to the technique.

Several incisions have been advocated for performing minimally invasive procedures, including some variants of upper and lower ministernotomy, anterior or side minithoracotomies, and may be performed either on the right or left side of the chest [11.20-22]. Although some cases of aortic prosthesis in our series were performed using upper ministernotomy, our preference has been present for intercostal minithoracotomy whenever possible.

There is difficulty in defining what is called minimally invasive cardiac surgery. A careful reading of the published study, as well as the observation of surgeries performed in several centers, shows that these surgeries range from those with relatively large incisions in the skin, with 8 to 10 cm in length, but with extensive dissection of the intercostal spaces and with remoteness and trauma pronounced in the ribs, and also surgeries with smaller incisions of 3-4 cm with minimal dissection, with exclusive use of retractors and soft tissue with the aid of video equipment or robotic systems [5,6]. Thus, comparison of results between different services becomes complex and difficult to interpret.

When we started our experience of valve surgeries with small thoracotomies, we are fully aware that they involve a learning curve and that patient selection, as well as a gradual evolution in reducing the size of the incision should be made with caution [1,6]. Thus, in initial cases we used incisions around 8-10 cm long, but, as the technique has been refined, this size may be reduced to incisions which

CVA = stroke. SD = standard deviation. MI = myocardial infarction. ICU = intensive care unit

The total bleeding postoperatively ranged from 50 to 3400 ml (mean=470 ± 277 ml), and blood transfusion was performed on 74 patients who received an average of 1.6 ± 1 units of PRBC. Only two patients underwent reoperation for excessive bleeding, being possible correction through the same incision of the original transaction.

The length of stay in the ICU ranged from 12 hours to 13 days (mean=2.8 ± 1.7 days) and length of hospitalization ranged from 4 to 30 days (mean=8.7 ± 4.5 days).

For clinical and echocardiographic assessment, surgical corrections were considered satisfactory. All ASDs were properly closed, and in patients with prosthetic heart valves, no importante paravalve leaks were detected.

Similarly, patients undergoing mitral valve repair remained with competent valves or backflow graded as trivial.

DISCUSSION Minimally invasive surgeries have been performed since the early 1990s, however, because they are technically more elaborate and require specific training, their acceptance is still limited. Data from the Society of Thoracic Surgery (STS) show that less than 20% of valve surgeries are performed by minimally invasive incisions, and there are few centers 388

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typically range from 4 to 6 cm in recent patients. With the development of the technique, our dissection of the intercostal spaces is minimal and corresponding for the size of the incision in the skin, and the removal of the intercostal space is limited, avoiding trauma to the ribs and thereby decreasing postoperative pain.

Some centers advocate the use of video or robotic systems for performing these surgeries [4,9,11]. In Brazil, Poffo et al. [11] reported their experience of minimally invasive surgeries with the aid of video, including being performed a pioneering procedure by periareolar access.

However, these surgeries are more complex and, even with the use of sophisticated technologies, there is a need for an incision of at least 3 to 4 cm in length, and some additional small incisions that serve as entry to the additional equipment without taking into account the high costs. The techniques employed allow us to perform the entire surgery under direct vision with incisions that are no more than 1 to 2 cm longer, being more accessible to groups who want to start with these procedures.

Patient selection for minimally invasive surgeries should be cautious and, in our opinion, can only be extended as it exceeds the initial learning curve. We find no justifiable decreasing the size of the incision to the detriment of the quality of the technique [8]. Thus, it should start with the simplest cases and with favorable anatomy, preventing cases of complex mitral repair or patients with unfavorable aortic root and with extreme calcification. In addition, some factors constitute relative or absolute contraindications for this type of surgery, such as important peripheral vascular disease, right thoracotomy and/or previous thoracic irradiation, concomitant need for surgeries such as coronary artery bypass grafting and thoracic deformities such as pectus excavatum [15].

Some technical aspects seem to be important for obtaining consistently satisfactory results. For anesthesia, the selective intubation should be avoided, since the possibility of occurrence of unilateral pulmonary edema which is a complication of complex handling [23]. The use of TEE is essential for the proper positioning of the arterial, venous and retrograde cardioplegia cannulas, as well as for monitoring various steps of the surgery, during the removal of air from the heart chambers and to monitor ventricular function and appropriate management of inotropic drugs, since we have no visualization of the heart as in the conventional surgeries [7,9]. In our series, we had a case of injury to the right ventricle through the tip of the venous cannula that could have been avoided with proper TEE control which was not available in this case.

The potential need for conversion to median thoracotomy has been reported in most published studies, being caused mainly when there is the occurrence of acute aortic dissection or rupture of the atrioventricular groove

[15]. In our initial series, in the only case with inaccessible bleeding, we performed an extension of thoracotomy on the left side of the chest to suture the tip of the left atrium that had been traumatized during aortic clamping.

Some studies suggest that performing minimally invasive surgeries can be associated with a higher incidence of stroke. Among the risk factors for this complication are older age, atheromatous aorta with diffuse retrograde arterial perfusion, using endoclamps or perform the operation without aortic clamping during the heart fibrillating[1]. For this reason, we think that the retrograde CPB by femoral vessels should be preceded by extensive preoperative assessment, and should be avoided in cases of diffuse atherosclerotic disease of the aorta, iliac or femoral arteries, as well as in patients with femoral vessels of small caliber. Alternatively, there is the possibility of axillary artery cannulation in selected cases, also the ascending aortic cannulation, as recommended by Crooke et al [16]. In our experience, we use retrograde perfusion in all cases where the incision was performed by side minithoracotomy, and the aortic clamping performed using retractable clamp. In cases where there was more pronounced aortic atheromatosis, surgeries were performed by ministernotomy and central arterial cannulation. With this methodology, our incidence of stroke was two (2%) cases, both in elderly aortic patients. There were no major brain complications in any mitral or ASD patient.

The venous drainage performed with the aid of vacuum is usually adequate, however, in cases where the right side of the heart is approached, or when the drainage is poor, placing a second cannula, both by venipuncture directly into the internal jugular or cava above should be performed. [5] A possible criticism of minimally invasive surgeries refers to longer times of aortic clamping and CPB. In our experience, aortic clamping, although longer than in conventional surgeries, was within a range of time quite reasonable, and apparently caused no increase in inflammatory response nor disturbances in blood clotting [24].

The average amount of total bleeding of 470 ml can be considered low, comparing favorably with other published series [15,18]. Still, 70% of our patients received at least one unit of blood transfusion, suggesting the need for more stringent treatment protocols in the immediate postoperative period in our institution. Similarly, the incidence of reoperation for bleeding was low and, in both cases, the source of the bleeding was coming from the thoracic wall, which reinforces the need for detailed review of hemostasis, since the view of the intercostal spaces is very limited with this type of incision [15].

Although this study is not comparative, subjective impression was that the patients presented easier 389

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postoperative functional recovery, with ambulation and earlier return to daily activities compared with those patients undergoing surgeries involving medians thoracotomy. The level of personal satisfaction with the incision and the cosmetic aspects was also high.

2. Cheng DC, Martin J, Lal A, Diegeler A, Folliguet TA, Nifong LW, et al. Minimally invasive versus conventional open mitral valve surgery: a meta-analysis and systematic review.

Innovations (Phila). 2011;6(2):84-103.

Limitations of the Study This study aimed to report our initial experience with valve surgeries and congenital heart disease with minimally invasive techniques. The number of cases undergone this type of surgery is still quite limited, and as it is not a comparative study, we can not make definitive inferences about their possible indications and about their real advantages and disadvantages.

CONCLUSIONS Our experience shows that valve surgeries, of correction of simple congenital heart disease and cardiac tumor resection can be performed safely and with results similar to those obtained with conventional techniques. The incidence of stroke was 2%, and postoperative morbidity was low. In addition, the functional recovery of patients is faster and satisfaction on the part of patients is at least subjectively better. Once overcome the learning curve and proper training of all staff involved, minimally invasive surgeries can become an attractive option for many patients with these conditions.

3. Falk V, Cheng DC, Martin J, Diegeler A, Folliguet TA, Nifong LW, et al. Minimally invasive versus open mitral valve surgery: a consensus statement of the international society of minimally invasive coronary surgery (ISMICS) 2010. Innovations (Phila).

2011;6(2):66-76.

4. Gao C, Yang M, Xiao C, Wang G, Wu Y, Wang J, et al.

Robotically assisted mitral valve replacement. J Thorac Cardiovasc Surg. 2012;143(4 Suppl):S64-7.

5. Woo YJ, Seeburger J, Mohr FW. Minimally invasive valve surgery. Semin Thorac Cardiovasc Surg. 2007;19(4):289-98.

6. Casselman FP, Van Slycke S, Wellens F, De Geest R, Degrieck I, Vermeulen Y, et al. From classical sternotomy to truly endoscopic mitral valve surgery: a step by step procedure.

Heart Lung Circ. 2003;12(3):172-7.

7. Glauber M, Miceli A, Bevilacqua S, Farneti PA. Minimally invasive aortic valve replacement via right anterior minithoracotomy: early outcomes and midterm follow-up. J Thorac Cardiovasc Surg. 2011;142(6):1577-9.

8. Anyanwu AC, Adams DH. Should complex mitral valve repair be routinely performed using a minimally invasive approach?

Curr Opin Cardiol. 2012;27(2):118-24.

9. Casselman FP, Van Slycke S, Wellens F, De Geest R, Degrieck I, Van Praet F, et al. Mitral valve surgery can now routinely be performed endoscopically. Circulation. 2003;108 Suppl 1:II48-54.

10. Poffo R, Pope RB, Selbach RA, Mokross CA, Fukuti F, Silva Júnior I, et al. Video-assisted cardiac surgery: results from a pioneer project in Brazil. Rev Bras Cir Cardiovasc. 2009;24(3):318-26.

11. Poffo R, Pope RB, Toschi AP, Mokross CA. Video-assisted minimally invasive mitral valve repair: periareolar approach.

Rev Bras Cir Cardiovasc. 2009;24(3):425-7.

12. Fortunato Jr JA, Pereira ML, Martins ALM, Pereira DSC, Paz MA, Paludo L, et al. Cirurgia cardíaca video-assistida.

Rev Bras Cir Cardiovasc. 2012;27(1):24-37.

REFERENCES 1. Gammie JS, Zhao Y, Peterson ED, O’Brien SM, Rankin JS, Griffith BP. J. Maxwell Chamberlain Memorial Paper for adult cardiac surgery. Less-invasive mitral valve operations: trends and outcomes from the Society of Thoracic Surgeons Adult Cardiac Surgery Database. Ann Thorac Surg.

2010;90(5):1401-8.

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13. Dias RR, Sobral MLP, Avelar Jr SF, Santos GG, Lima MAVB, Haddad V, et al. Cirurgia da valva aórtica: estudo prospectivo e randomizado da miniesternotomia versus esternotomia convencional. Rev Bras Cir Cardiovasc. 1999;14(2):98-104.

14. Speziale G, Nasso G, Esposito G, Conte M, Greco E, Fattouch K, et al. Results of mitral valve repair for Barlow disease (bileaflet prolapse) via right minithoracotomy versus conventional median sternotomy: a randomized trial. J Thorac Cardiovasc Surg. 2011;142(1):77-83.

Costa F, et al. - Initial experience with minimally invasive cardiac operations

15. Modi P, Rodriguez E, Hargrove WC 3rd, Hassan A, Szeto WY, Chitwood WR Jr. Minimally invasive video-assisted mitral valve surgery: a 12-year, 2-center experience in 1178 patients.

J Thorac Cardiovasc Surg. 2009;137(6):1481-7.

16. Crooke GA, Schwartz CF, Ribakove GH, Ursomanno P, Gogoladze G, Culliford AT, et al. Retrograde arterial perfusion, not incision location, significantly increases the risk of stroke in reoperative mitral valve procedures. Ann Thorac Surg.

2010;89(3):723-9.

17. Sansone F, Punta G, Parisi F, Dato GM, Zingarelli E, Flocco R, et al. Right minithoracotomy versus full sternotomy for the aortic valve replacement: preliminary results. Heart Lung Circ.

2012;21(3):169-73.

18. Santana O, Reyna J, Grana R, Buendia M, Lamas GA, Lamelas J. Outcomes of minimally invasive valve surgery versus standard sternotomy in obese patients undergoing isolated valve surgery. Ann Thorac Surg. 2011;91(2):406-10.

19. Mihos CG, Santana O, Lamas GA, Lamelas J. Outcomes of right minithoracotomy mitral valve surgery in patients with

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previous sternotomy. Ann Thorac Surg. 2011;91(6):1824-7.

20. Saunders PC, Grossi EA, Sharony R, Schwartz CF, Ribakove GH, Culliford AT, et al. Minimally invasive technology for mitral valve surgery via left thoracotomy: experience with forty cases. J Thorac Cardiovasc Surg. 2004;127(4):1026-31.

21. Svensson LG. Minimal-access "J" or "j" sternotomy for valvular, aortic, and coronary operations or reoperations. Ann Thorac Surg. 1997;64(5):1501-3.

22. Svensson LG. Minimally invasive surgery with a partial sternotomy "J" approach. Semin Thorac Cardiovasc Surg. 2007;19(4):299-303.

23. Madershahian N, Wippermann J, Sindhu D, Wahlers T. Unilateral re-expansion pulmonary edema: a rare complication following one-lung ventilation for minimal invasive mitral valve reconstruction. J Card Surg. 2009;24(6):693-4.

24. Brinkman WT, Hoffman W, Dewey TM, Culica D, Prince SL, Herbert MA, et al. Aortic valve replacement surgery: comparison of outcomes in matched sternotomy and PORT ACCESS groups. Ann Thorac Surg. 2010;90(1):131-5.

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ORIGINAL ARTICLE

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Biocompatibility of Ricinus comunnis polymer compared to titanium implant used in artificial hearts. Experimental study in guinea pigs Biocompatibilidade do polímero da mamona comparada ao implante de titânio para corações artificiais.

Estudo experimental em cobaias

Luiz Fernando Kubrusly1, Yorgos Luiz Santos de Salles Graça2, Enéas Eduardo Sucharski3, Ana Cristina Lira Sobral4, Marcia Olandoski5, Fernando Bermudez Kubrusly6

DOI: 10.5935/1678-9741.20120067

RBCCV 44205-1398

Abstract Objective: The aim of the present investigation is to determine if the tissue reaction to the Riccinus communis (mamona) polymer has significant statistical difference compared to the tissue reaction provoked by the titanium implant.

Methods: Thirty two Cavia porcellus were divided into four groups containing eight animals each one. We implanted the two types of materials in the retroperitoneal space of all the animals. They were sacrificed at 7, 20, 30 and 40 days after surgery and the samples were submitted to histological study.

Results: The quantitative analysis did not show difference between the tissue reaction of the two materials (P>0.05).

The analysis of the qualitative variable also did not show difference between the tissue reaction of the materials (P>0.05).

Conclusion: Macroscopic and microscopic results showed that the castor oil polymer implant has no significant statistical difference compared to the titanium implant tissue reaction.

1. Denton Cooley-CEVITA Institute, Post-Doctorate in Medicine from Universidade Federal do Paraná, Director of the Heart Institute of Curitiba - Hospital Vita, Curitiba, PR, Brazil.

Realization of experimental surgeries; writing of the manuscript.

2. Denton Cooley-CEVITA Institute, Academic Head of the Denton Cooley Research Institute, Graduating in medicine from Faculdade Evangélica do Paraná, Curitiba, PR, Brazil. Review of literature; realization of experimental surgeries; writing of the manuscript.

3. Denton Cooley-CEVITA Institute; Scientific Initiation Scholarship PIBIC / CNPp 2011-2012; Graduating in medicine from Faculdade Evangélica do Paraná, Curitiba, PR, Brazil. Review of literature; realization of experimental surgeries; writing of the manuscript.

4. Faculdade Evangélica do Paraná; Professor and Pathologist, Curitiba, PR, Brazil. Reading and Report of the blades of pathological analysis.

5. Pontifícia Universidade Católica do Paraná - PUCPR; Doctorate

in Health Sciences PUCPR, Curitiba, PR, Brazil. Statistical analysis.

6. Denton Cooley-CEVITA Institute; Resident in Cardiovascular Surgery at the Texas Heart Institute, Houston, Texas, USA. Realization of experimental surgeries.

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Descriptors: Prosthesis implantation. Heart, artificial.

Ricinus. Implants, experimental. Guinea pigs.

Resumo Objetivo: Determinar se a reação tecidual do implante retroperitoneal do polímero de óleo de mamona (Pm) é significativa ou não por meio de análise histopatológica, tendo como controle o implante de titânio (Ti).

Métodos: Estudo experimental, intervencionista e randomizado com 32 cobaias. Os animais foram divididos em quatro grupos iguais e eutanasiados com 7, 20, 30 e 40 dias após

Work performed at the Denton Cooley - CEVITA Institute, InCor, Curitiba, PR, Brazil.

Correspondence address: Luiz Fernando Kubrusly Rua Alferes Ângelo Sampaio, 1896 – Batel – Curitiba, PR, Brazil – Zip code: 80420-160 E-mail: kubrusly@incorcuritiba.com.br Article received on May 8th, 2012 Article approved on August 23th, 2012

Kubrusly LF, et al. - Biocompatibility of Ricinus comunnis polymer compared to titanium implant used in artificial hearts. Experimental study in guinea pigs

Abbreviations, acronyms and symbols CO2 COBEA CAD HE CHF Pc PVPI Ti

Carbon dioxide Colégio Brasileiro de Experimentação Animal Circulatory assist devices Hematoxylin-eosin Congestive heart failure Polymer castor Polyvinylpyrrolidone iodine Titanium

o ato cirúrgico. Foram confeccionadas lâminas em hematoxilina-eosina e em tricrômio de Masson. Na comparação dos tipos de material em relação a variáveis quantitativas, foi considerado o teste não-paramétrico de Wilcoxon. Em relação a essas variáveis, os grupos definidos pelo dia do sacrifício foram comparados usando-se o teste não-paramétrico de

INTRODUCTION Cardiovascular diseases are the leading cause of death worldwide and, for the first time in history, that leadership is independent of socioeconomic status of countries.

Considering the aging population worldwide, despite the epidemiological and medical practices, it is expected that this prevalence can be maintained or even increase in the coming decades [1].

Congestive heart failure (CHF) is among those diseases and competes today with a high prevalence in several countries. In the United States of America, an estimated 400 000 new cases per year [2].

Since the pioneering work of De Bakey in 1966 [3], with the placement of the first ventricular assist device, and Cooley in 1969 [4], with the implantation of the first totally artificial heart in a patient with cardiogenic shock, cardiovascular medicine has been trying to develop a technology capable of keeping these serious patients alive.

The circulatory assist devices (CADs), recently became a key part of the therapeutic armamentarium in the treatment of cardiogenic shock and in maintaining circulatory support in patients with terminal heart failure [5,6]. The use of these devices has been indicated as a bridge to heart transplantation, as support for the recovery of the heart in acute myocardial infarction and post-cardiac surgery [7,8].

Another indication restricted to centers much more research in this area is the destination therapy for treatment of CHF

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Kruskal-Wallis. Os resultados obtidos no estudo da fibrose foram expressos por frequências e percentuais. Para a comparação entre os grupos definidos pelo dia do sacrifício, em relação a variáveis qualitativas dicotômicas da fibrose, foi considerado o teste exato de Fisher. Para avaliar a diferença entre os materiais titânio e polímero em cada grupo, ainda em se tratando da fibrose, foi considerado o teste binomial. Valores de P<0,05 indicaram significância estatística.

Resultados: A análise das variáveis quantitativas não demonstrou diferença nas reações teciduais entre os materiais (P>0,05). A análise da variável qualitativa também não demonstrou diferença entre as reações teciduais dos materiais (P>0,05).

Conclusão: Não foi encontrada significância estatística entre a reação tecidual do Pm e do Ti. Descritores: Implante de prótese. Coração artificial.

Ricinus. Cobaias. Implantes experimentais.

terminal. Some studies have shown mortality at 1 year, similar among heart transplant and destination therapy. [9].

Since 1997, we began developing a CAD that was accessible to public service in our country. We perform tests “in vitro” [2] and idealized device constructed from titanium, and the vast majority of the equipment available in the world. Tests “in vivo” experiments were carried out on sheep and proved the effectiveness of the device [2].

Within our main objective, which is the development of national equipment, adapted to the resources of our country, we are in the process of replacing high-cost mechanical parts for substitutes acquired nationally and therefore at lower costs.

Castor oil is a vegetable oil extracted from the seeds of the plant Ricinus communis, which is found in tropical and subtropical regions. It viscous liquid obtained by pressing (hot or cold) of seeds or by solvent extraction [10]. Studies of the use of castor oil and derivatives for the synthesis of polyurethanes began in late 1940 with the preparation of polyurethane films for coating surface [11].

The first reports on the use of polyurethanes in medical applications date back to 1959 when Mandarino & Salvatore implanted a rigid foam polyurethane for fixation of bone in situ.

The polyurethanes of castor oil can be obtained with different characteristics, since the most flexible, as elastomers, to the most rigid, like the bone cements.

Several biocompatibility studies were conducted mainly in 393

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bone: in orthodontic implants, bone fixation plates, sealants [12] in cranioplasties in orthopedic prostheses and orbital reconstruction [13].

The objective of this study is to evaluate this type of polyurethane castor, to obtain histological data sufficient to prove that the low inflammatory reaction in the retroperitoneal space of guinea pigs compared to that of titanium.

from the ground. The animals received filtered water and standard commercial diet ad libitum until 4 hours before euthanasia. The analgesia protocol followed dose Tramadol 1 mg / kg of 12-24 hours duration [15]. The animals were previously acclimated for a period of 7 days prior to the realization of the experiments. Surgical procedures were performed under refrigeration, sterile technique and material, in the Clinical and Experimental Surgery Laboratory of the Faculdade Evangélica do Paraná (Figure 1).

METHODS Interventional and randomized experimental study, developed by the Denton Cooley Institute in the Laboratory of Histology and Cell Biology, in the Animal Clinical and Surgical Experimentation Laboratory of Faculdade Evangélica do Paraná.

Ethical aspects This manuscript was submitted to the Ethics Committee in Research of the Evangelical Beneficent Society of Curitiba and approved with number 4277/11.

This was followed by the Act 6638 of May 8, 1979, Standards for the Practice of Scientific-Didactic Animal Vivisection.

The standards established in the “Guide for the Care and Use of Laboratory Animals” (Institute of Laboratory Animal Resources, National Academy of Sciences, Washington, DC, 1996) and the precepts of the Brazilian College of Animal Experimentation (COBEA) were also obeyed.

Sample A total of 32 guinea pigs (Cavia porcellus), Rodentia, Mammalia, males, weighing between 250 and 300 grams (mean: 289.15 ± 17.47), from the Institute of Technology of Paraná, aged 4 and 6 months Life, previously healthy, created and maintained under similar environmental conditions and food were utilized.

The animals were randomly divided into four groups (A, B, C, D) of equal size. They were euthanized in a CO2 gas chamber, four animals per time at 7 (group A), 20 (group B), 30 (group C) and 40 (group D) days after implant surgeries [14].

Setting experimentation The guinea pigs were housed according to the Manual of Technical Standards for Animal Experimentation Animal Facility of the Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo. [15] The laboratory used was the one of Faculdade Evangélica do Paraná, where the light / dark cycle and humidity are the general environment. The temperature was kept constant (24°C) and their cages were placed all at the same height 394

Anesthesia The animals were anesthetized as recommended by Radde et al. [16], using ketamine and xylazine (87/13 mg / kg, respectively), both applied intraperitoneally.

Description of surgery Once anesthetized, the animal was positioned prone and shaving was done bilaterally with scissors along the back.

Subsequently, it was performed antisepsis of the surgical field with polyvinylpyrrolidone iodine (PVP).

It was performed local anesthesia with lidocaine 2% diluted in physiological saline solution. The procedure was then an incision of 2 cm in length at 2 cm of the left vertebral axis in the region between the last rib and iliac crest. The procedure crossed the epithelium, the subcutaneous tissue, fascia and hit the muscular layer. The muscle was carefully opened and hit the virtual retroperitoneal space where the titanium (Ti) disc was implanted. The deep and superficial incision planes were sutured with 3-0 nylon line [17], with continuous simple stitches. On the right side it was proceeded in the same way, but the implant was polymer castor (Pc).

Collecting material for histopathologic study The surgical device was removed in monobloc and immediately immersed in neutral buffered formalin 10% and remained in fixative for 72 hours at room temperature.

After fixation, the discs of Ti and Pc were removed by lateral incision and then the pieces were washed in water for 24 hours, processed routinely and embedded in paraffin. The material received cuts of 6 micrometers and was stained by using hematoxylin-eosin (HE) for the cellular elements and capillaries, and by the technique of Masson trichrome with Blue Nile for collagen fibrosis.

Analysis was performed by means of optical microscope Olympus® brand, model DX 50.

Microscopic examination was performed in order to assess the inflammatory process of each material, i.e., congestion and the formation of granulation tissue periimplant. For this, it has been found quantitatively the number of inflammatory cells in each blade of each group.

The cells analyzed were histiocytes, neutrophils, lymphocytes and giant cells. The histiocyte considered in

Kubrusly LF, et al. - Biocompatibility of Ricinus comunnis polymer compared to titanium implant used in artificial hearts. Experimental study in guinea pigs

Rev Bras Cir Cardiovasc 2012;27(3):392-400

Fig. 1 - Implants Pc (A) and Ti (B) in anatomical site. In C, you can see the implant Pc; in D, we have the implant Ti

this study as a histopathologic type of macrophage of reticuloendothelial origin, which is normally stationary and inactive, but could become active if stimulated, a neutrophil, a polynuclear leukocyte of neutrophil granules, the lymphocyte, a type of white blood cell having between 1012 micromeres in diameter, a round nucleus with condensed chromatin and scarce cytoplasm a bit basophilic; the giant cell, as being that formed by the union of several distinct cells.

Regarding the presence of fibrosis, this was classified as mild, moderate or severe.

For microscopic examination it was used 10X eyepiece, focusable and objective of 40X. For reading, the cell types were counted in 10 microscopic fields with the abovementioned increase in areas altered by inflammatory foreign body.

Preparation and origin of implants The Ti was the control material, while Pc was the material put to test. The alloy of Ti was obtained from commercial

establishment, cylindrical rods with 5 mm diameter characterized as grade 2; the bar chemical composition was 99.7% Ti, 0.009% C, 0.095% Fe, 0.0003% H, 0.0038% N and 0.152% O2; regarding the mechanical properties, the bar presented% Elongation (N) L = 32,% RED. IN AREA L = 52, L = 78.8 ksi UTS and YS ksi (0.2%) L = 57.

The Pc was obtained in liquid form by laboratory specializing in polymers used in the medical field (Poliquil Araraquara, SP, Brazil). The process of making the implants castor starts from equal parts of a polyol and an ampoule bulb vegetable polyurethane resin hardener which are mixed with glass rod in a beaker for 3 minutes until complete homogenization. There was no addition of calcium carbonate. The homogenate obtained was placed in two insulin syringes. After polymerization completed, the syringes were sectioned with a scalpel blade in transverse sections of 3 mm thickness, then withdrawing the plastic of the syringe barrel [18]. Thus we obtained the discs of 3 mm thick and 5 mm in diameter to be used in retroperitoneal implantation in mice. The antisepsis of the disks was done 395

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Rev Bras Cir Cardiovasc 2012;27(3):392-400

by submerging them in alcohol 70째 for 15 minutes. The process of making the Ti implants was performed in a specialized factory (Neodent - Curitiba, PR, Brazil). The bar of Ti was arrested plate lathe (20A-Tormax ROMI) and sectioned along with cutting fluid (Quimatic oil), then the disks obtained were made square to be free of spikes or irregularities resulting from the first process. Ti implants had the same dimensions of the castor implants and were also sterilized in alcohol 70 째.

(Pc: mean 0, median 0, Ti: mean 0, median 0) and giant cells (Pc: mean 4.3, median 3; Ti: mean 9.9, median 9), no difference was found between the two materials (P> 0.05).

In group D, by quantifying lymphocytes (Pc: mean 3, median 3; Ti: mean 8.7, median 8), histiocytes (Pc: mean 120.1, median 115; Ti: mean 157.1, median 176 ), neutrophils (Pc: mean 0, median 0, Ti: mean 0, median 0) and giant cells (Pc: mean 4.3, median 5; Ti: mean 5.3, median 5), no difference was found between The two materials (P> 0.05).

Then, for each type of material tested the null hypothesis that results in the four groups are equal, versus the alternative hypothesis that at least one of the groups have different results than others. Where there rejection of the null hypothesis (P <0.05), groups were compared two by two.

When comparing the four groups of Pc each other, it was observed that there was a tendency of reducing the number of inflammatory cells over time post-operatively (P <0.05). In making the same analysis for the 4 groups of Ti, trend was also observed for the reduction of inflammatory cells over time (P <0.05) (Figures 2 to 5).

The peri-implant fibrosis tended to be equally sharp in both types of implanted material with the passage of time.

In groups A and C, when comparing the two types of materials implanted P was not highly significant (P = 0.5).

In the other groups, to make the same analysis, we found that P was not highly significant (P = 1).

Statistical analysis Comparing the types of material with respect to quantitative variables was considered the nonparametric Wilcoxon [19]. In terms of these variables, the groups defined by the day of sacrifice were compared using the nonparametric Kruskal-Wallis test [19]. The results obtained in the study of fibrosis and frequencies were expressed as percentages. For comparison between the groups defined by the day of sacrifice, for dichotomous qualitative variables fibrosis, it was considered the Fisher exact test [19]. To evaluate the difference between titanium and polymer materials in each group, although in the case of fibrosis, it was considered the binomial test [19]. P values <0.05 were considered statistically significant. Data were analyzed with Statistica v.8.0 program.

RESULTS There were no complications related to the surgical site, such as dehiscence or infection.

Analysis of quantitative variables Initially considering each of the groups A, B, C and D for each of the variables relating to the number of lymphocytes, histiocytes, neutrophils and giant cells, we tested the null hypothesis that the results of Pc are equal to Ti, versus the alternative hypothesis of different results.

In group A, by quantifying lymphocytes (Pc: mean 35, median 34; Ti: mean 34.1, median 34), histiocytes (Pc: mean 279, median 270; Ti: mean 283.9, median 298), neutrophils (Pc: mean 0.4, median 0, Ti: mean 0.9, median 0) and giant cells (Pc: mean 7.1, median 6; Ti: mean 6, median 6), no difference was found between The two materials (P> 0.05).

In group B, by quantifying lymphocytes (Pc: mean 32.4, median: 32.5, Ti: mean 46.1, median 40.5), histiocytes (Pc: mean 183.6, median 205; Ti: mean: 182.8, median 147), neutrophils (Pc: mean 11.5, median 3; Ti: mean 5.8, median 3) and giant cells (Pc: mean 5.3, median 3.5, Ti: mean 1 , 6, median 1), no difference was found between the two materials (P> 0.05).

In group C, by quantifying lymphocytes (Pc: mean 14.4, median 15; Ti: mean 20.1, median 16), histiocytes (Pc: mean 275.6, median: 278; Ti: mean 295.7, median 278), neutrophils 396

Study of the qualitative variable Regarding the correlation study the intensity of the periimplant fibrosis in group A, it was found that five cases (62.5%) of Pc presented not accentuated grade, while the Ti showed two cases (25%); in regarding the high level of fibrosis in group B, there were three cases (37.5%) of Pc and six cases (75%) P value Ti (Ti x Pc) in group A was 0.500, i.e., not significant, since P> 0.05.

Regarding the study in the group B, it was observed that three patients (37.5%) of Pc showed no accentuated degree, while the Ti showed two cases (25%); regarding the high level of fibrosis in that group it had five cases (62.5%) of Pc and six cases (75%) P value Ti (Ti x Pc) in Group B was 1, i.e., not significant, since P> 0.05.

Regarding the study in the group C, there was a case (12.5%) of Pc that showed no accentuated degree, while the Ti showed two cases (25%); regarding the high level of fibrosis in that group there were seven cases (87.5%) of Pc and six cases (75%) P value Ti (Ti x Pc) in group C was 0.500, i.e., not significant, since P> 0, 05.

Regarding the study in the group D, it was found that three cases (37.5%) of Pc and also three cases (37.5%) of Ti showed no accentuated degree, regarding the high level of fibrosis in that group there were five cases (62.5%) of Pc and number of cases of the same P value Ti (Ti x Pm) in group D 1, i.e., not significant, since P> 0.05 ( Figure 6).

Kubrusly LF, et al. - Biocompatibility of Ricinus comunnis polymer compared to titanium implant used in artificial hearts. Experimental study in guinea pigs

Rev Bras Cir Cardiovasc 2012;27(3):392-400

Fig. 2 - Quantitative analysis of lymphocytes according to defined group

Fig. 4 - Quantitative analysis of neutrophils according to defined group

Fig. 3 - Quantitative analysis of histiocytes according to defined group

DISCUSSION It was chosen the Cavia porcellus by experience of the research group, as its size and docile nature facilitated the manipulation of the retroperitoneum. The serosa of smaller animals, such as rats and Wistar mice is more labile, impeding dilatation of the retroperitoneal space, so complications including migration of the implant and rupture of the peritoneal membrane could be more frequent in these smaller animals.

We used a guinea pig for every two implants (Pc and Ti). It was decreased, thus, the number of animals in the experiment to deploy a different material in each hemisphere

Fig. 5 - Quantitative analysis of giant cells according to defined group

of the same guinea pig. The implant site was the retroperitoneum, for it is a membrane similar to the pericardial and pleural membranes of the thoracic cavity, site characteristic of implantable circulatory assist devices.

Low cost materials, acceptable biocompatibility characteristics and abundant in nature would be ideal to replace other materials that already exist in practice, but that have high costs and are difficult to obtain.

The favorable characteristics found in Pc were first cited by the authors such as Ohara et al. [20] Carvalho et al. [21] Ignacio et al. [22] and Silva [23], paving the way for the use of this polymer in orthopedics, orthodontics, surgery and oral maxillofacial neurosurgery. Furthermore, the system of 397

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Rev Bras Cir Cardiovasc 2012;27(3):392-400

Fig. 6 - Blades of group D of Ti (A) and Pc (B) in the Masson’s Trichrome staining, indicating moderate fibrosis in both

obtaining Pc is very attractive because it eliminates the presence of catalysts; it has simple processability and flexibility in the formulation, thereby adding other components without interfering with the reaction.

There is versatility of “cure” temperature with a maximum exothermic peak of 45 degrees centigrade, with no residual free monomer production post-reaction, which was not desirable in a circulatory assist device, common among polymers and encouraged researchers to use titanium therefore. Dias et al. [24] conducted a study using four capuchin monkeys, placing an implant of a bone defect in Pc, previously performed in the nasal dorsum of these animals; later, histological analysis did not reveal the presence of foreign body granuloma or phagocytic cells.

Although our study did not perform analysis on bone tissue, there was also the presence of foreign body granuloma in histological analysis. Another study of Mastrantonio & Ramalho [18] evaluated the response of connective tissue of mice to Pc for 60 days, and again the result was favorable biocompatibility.

The Ti is considered inert and authors like Bothe et al.

[25] have amply demonstrated their applicability in metal alloys in the medical field since the mid-twentieth century.

Ti alloys are widely used as part replacement of bones in the human body implantable materials such as screws and plates, which today appear including reconstructive surgery. Likewise, the Pm is increasing the scope of its area of use.

It was observed in this study that the predominant type of inflammation, in both studied materials (Pc and Ti), was the chronic inflammation, i.e., predominance of mononuclear cells and that, regardless of the period analyzed, the granulation tissue was predominant in non accentuated.

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The initial period of 7 days is directly related to suturing performed during surgery. Siqueira & Dantas [26] described as the period of deposition of collagen and hyaluronic acid, which compounds are produced in an attempt to rebuild the damaged tissues. In the present study, the first 7 days, inflammation was non accentuated, beyond that, there was no statistically significant difference in the degree of granulation tissue in both groups.

The largest amount of fibrosis found in the last two groups, i.e., 30 and 40 days postoperatively, was discordant results of Costa et al. [27] found that the formation of a dense fibrous tissue involving the Pc. In this study, for both materials, the adjacent tissue showed histological characteristics of normal, and show a tendency to reduced tissue reaction with the progression of the time of deployment.

Another situation was that there was gross and microscopic structural degradation of the polymer when subjected to temperatures from the animal. This can be confirmed by the thesis that the polyurethanes showed thermal stability up to 210 ° C, demonstrating that, at room temperature, these polymers have no possibility to undergo thermal decomposition [28].

In addition to the stability at high temperatures, Pc is a Brazilian technology and represents the possibility of an implantable device with less weight for the patient. The device in our study, K-pump, made of steel, has its weight of 194 g. With the same dimensions, built in titanium, the projected weight is between 85-95 g. With the polymer castor, the weight will be around 50 g, weight below the average of major totally implantable devices currently available and suitable for pediatric patients and small adults.

Kubrusly LF, et al. - Biocompatibility of Ricinus comunnis polymer compared to titanium implant used in artificial hearts. Experimental study in guinea pigs

CONCLUSION The tissue reaction induced by the two materials is very similar. There was no statistically significant difference between the tissue reaction caused by implantation of Pc and tissue reaction caused by Ti implantation in guinea pigs.

ACKNOWLEDGEMENTS Denton Cooley Research Institute, for supporting and encouraging us in this work.

Vita Studies Center, which has provided conditions for this study.

The company Poliquil (Araraquara, SP, Brazil), in particular Messrs. Antonio Carlos Rossi and Alexandre Guillen, who helped provide the polymer castor.

The company Neodent (Curitiba, Brazil), in particular to Mr. Adailton Becker, who helped us with the handling and cutting of titanium parts.

Faculdade Evangélica do Paraná, for the solicitude and support at all stages of this research.

Rev Bras Cir Cardiovasc 2012;27(3):392-400

7. Portner PM, Oyer PE, Pennington DG, Baumgartner WA, Griffith BP, Frist WR, et al. Implantable electrical left ventricular assist systems: bridge to transplantation and the future. Ann Thorac Surg. 1989;47(1):142-50.

8. Shreenivas SS, Rame JE, Jessup M. Mechanical circulatory support as a bridge to transplant or for destination therapy.

Curr Heart Fail Rep. 2010;7(4):159-66.

9. Frazier OH, Rose EA, Macmanus Q. Multicenter clinical evaluation of the HeartMate 1000 IP left ventricular assist device. Ann Thorac Surg. 1992;53(6):1080-90.

10. Chierice GO, Claro Neto S. Aplicação industrial do óleo. In: Azevedo DMP, Lima EF, eds. O agronegócio da mamona no Brasil. Brasília:Embrapa;2001.

11. Saunders JH, Frish KC. Polyurethanes: chemistry and technology. New York:John Wiley;1962. 368p.

12. Fedak PW, Kolb E, Borsato G, Frohlich DE, Kasatkin A, Narine K, et al. Kryptonite bone cement prevents pathologic sternal displacement. Ann Thorac Surg. 2010;90(3):979-85.

13. Gurgel JD, Alves Filho L, Farias VLD, Portugal AM, Sarmento Júnior KM. Ricinus communis membrane for orbital reconstruction. Braz J Otorhinolaryngol. 2011;77(2):268.

14. Brito MKM, Schellini SA, Padovani CR, Pellizzon CH, Neto CGT. Inclusões de quitosana no subcutâneo de rato: avaliação clínica, histológica e morfométrica. Anais Bras Derm.

2009;84(1):35-40.

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2010;94(5):694-702.

2. Kubrusly LF, Martins AF, Madeira J, Savytzky S, Wollman D, Melhem A, et al. Dispositivo de assistência circulatória mecânica intraventricular de fluxo axial: estudo in vitro. Rev Bras Cir Cardiovasc. 2000;15(2):169-72.

3. Tayama E, Olsen DB, Ohashi Y, Benkowski R, Morley D, Noon GP, et al. The DeBakey ventricular assist device: current status in 1997. Artif Organs. 1999;23(12):1113-6.

4. Gray NA Jr, Selzman CH. Current status of the total artificial heart. Am Heart J. 2006;152(1):4-10.

5. Dinkhuysen JJ, Andrade A, Contreras C, Paulista PP, LEME J, Manrique R. Estudo experimental da aplicação do ventrículo artificial eletromecânico pulsátil implantável. Rev Bras Cir Cardiovasc. 2011;26(1):76-85.

6. Moreira LFP; Benício A. Assistência circulatória mecânica: uma grande lacuna na cirurgia cardíaca brasileira. Rev Bras Cir Cardiovasc. 2010;25(4):X-XII.

15. Taborda PC, Carlos T. Manual de normas técnicas. Biotério de experimentação animal. São Paulo: Departamento de Microbiologia Instituto de Ciências Biomédicas – USP; 2004.

16. Radde GR, Hinson A, Crenshaw D, Toth LA. Evaluation of anaesthetic regimens in guineapigs. Lab Anim.

1996;30(3):220-7.

17. Ribeiro CMB, Silva Júnior VA, Silva Neto JC, Vasconcelos BCE. Estudo clínico e histopatológico da reação tecidual às suturas interna e externa dos fios monofilamentares de nylon e poliglecaprone 25 em ratos. Acta Cir Bras. 2005;20(4):284-91.

18. Mastrantonio SS, Ramalho LTO. Mouse connective tissue reaction to poliurethane derived from castor oil. Rev Odontol UNESP. 2003;32(1):31-7.

19. Siegel S, Castellan JR, John N. Estatística não-paramétrica para ciências do comportamento. 2ª ed. Porto Alegre: Artmed Editora; 2006.

20. Ohara GH, Kojima KE, Rossi JC, Telles M, Soares TVC, Salomão C, et al. Estudo experimental da biocompatibilidade do polímero poliuretano da mamona implantada intra-óssea e intra-articular em coelhos. Acta Ortoped Bras.

1995;3(2):62-8.

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21. Carvalho TL, Araújo CA, Teófilo JM, Brentegani LG. Histologic and histometric evaluation of rat alveolar wound healing around polyurethane resin implants. Int J Oral Maxillofac Surg. 1997;26(2):149-52.

25. Bothe RT, Beaton LE, Davenport HA. Reaction of bone to multiple metallic implants. Surg Gynecol Obstetr.

1940;71:598-602.

22. Ignácio H, Mazzer N, Barbieri CH, Chierici G. Uso da poliuretana derivada do óleo de mamona para preencher defeitos ósseos diafisários segmentares do rádio. Estudo experimental em coelhos. Rev Bras Ortop.

1997;32(10):815-21.

23. Silva MJA. Estudo radiográfico das imagens convencionais e digitalizadas do comportamento do tecido ósseo frente ao implante do polímero de mamona em coelhos [Dissertação de mestrado]. Bauru:Faculdade de Odontologia de Bauru – USP;1999. 135p.

24. Dias PCJ, Granato L, Pretel H. Avaliação histológica da biocompatibilidade do polímero da mamona no dorso nasal de macacos-pregos. Cebus apella. Braz J Otorhinolaryngol.

2009;75(3):350-5.

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26. Siqueira Jr JF, Dantas CJS. Inflamação: aspectos biodinâmicos das respostas inflamatória e imunológica. Rio de Janeiro:Pedro Primeiro;1996.

27. Costa CAS, Marcantonio RAC, Hebling J, Teixeira HM, Kuramae M. Biocompatibilidade do polímero de poliuretana vegetal derivada do óleo de mamona em estudo comparativo com cimento de óxido de zinco e eugenol: avaliação histopatológica de implantes subcutâneos de ratos. Odonto 2000. 1997;1(1):44-8.

28. Pereira PHL. Estudo das propriedades físico-químicas da poliuretana derivada do óleo de mamona com potencial aplicação na área médica [Dissertação de mestrado]. São Carlos:Universidade de São Paulo, Instituto de Química de São Carlos;2010 [Acesso 2012-06-25]. Disponível em: http://www.teses.usp.br/teses/ disponiveis/75/75132/tde-26072010-141545/.

ORIGINAL ARTICLE

Rev Bras Cir Cardiovasc 2012;27(3):401-4

Intraoperative coronary grafts flow measurement using the TTFM flowmeter: results from a domestic sample Medida do fluxo intraoperatório com fluxômetro TTFM nos enxertos coronários: resultados de amostra nacional

José Ernesto Succi1, Luis Roberto Gerola2*, Guilherme de Menezes Succi3, Hyong Chun Kim4, Jorge Edwin Morocho Paredes5, Enio Bufollo6 * in memoriam

DOI: 10.5935/1678-9741.20120068

RBCCV 44205-1399

Abstract Objective: To evaluate intraoperative graft patency and identify grafts under risk of early occlusion.

Methods: Fifty four patients were submitted to coronary artery bypass surgery and the graft flow was assessed by the Flowmeter (Medtronic Medistim), which utilizes the TTFM method. Three patients had left main disease and 48 had normal or mildly reduced left ventricular function.

Results: In hospital mortality was 3.7% (two patients), one for mesenteric thrombosis and one due to cardiogenic chock. Seventeen patients (34%) were submitted to off pump CABG. Arterial Graft flow measures ranged from 8 to 106 ml/min (average 31.14 ml/min), and venous grafts flow ranged from 9 to 149 ml/min (average 50.42 ml/min).

Conclusion: Flowmeter use represents higher safety both for patients and surgeons. Even under legal aspects, the documentation provided by the device can avoid future questionings.

Descriptors: Flowmeters. Myocardial revascularization.

Coronary artery bypass. Angina pectoris.

1. Hospital Bandeirantes - Unifesp (São Paulo, SP, Brazil); Chief of Thoracic Surgery discipline Unifesp, São Paulo, SP, Brazil.

2. Hospital Bandeirantes - Unifesp; Unifesp Doctor of Science, São Paulo, SP, Brazil.

3. Hospital Bandeirantes, Doctor of Science from the School of Medicine, University of São Paulo, São Paulo, SP, Brazil.

4. Unifesp; Unifesp Master of Science, São Paulo, SP, Brazil.

5. Hospital Bandeirantes; residency in cardiovascular surgery at the Institute of Cardiology Dante Pazzanese, São Paulo, SP, Brazil.

6. Unifesp Professor, São Paulo, SP, Brazil.

Work performed at Hospital Bandeirantes - Federal University of São Paulo (Unifesp), São Paulo, SP, Brazil.

Resumo Objetivo: Avaliar a perviedade dos enxertos no intraoperatório e identificar enxertos com risco de oclusão precoce.

Métodos: Cinquenta e quatro pacientes foram submetidos à revascularização do miocárdio e foi utilizado o fluxômetro (Medtronic Medi-Stim) que utiliza o método de tempo de trânsito (TTFM) para avaliação do fluxo nos enxertos. Três pacientes tinham lesão de tronco de artéria coronária esquerda e 48 apresentavam função ventricular normal ou pouco comprometida.

Resultados: A mortalidade hospitalar foi de dois (3,7%) pacientes, um por trombose mesentérica e outro por choque cardiogênico. Dezessete (31,4%) pacientes foram operados sem circulação extracorpórea (CEC). O fluxo no enxerto

Correspondence address: Guilherme de Menezes Succi Rua Pedro de Toledo, 980, cj 75– Vila Clementino – São Paulo-SP, Brazil – CEP 04039-002 E-mail: guilherme@succi.com.br Article received on May 9th, 2012 Article accepted on September 5th, 2012

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Abbreviations, acronyms and symbols CPB FC DF% PI TTFM LV

Cardiopulmonary Bypass Functional Class Diastolic filling Pulsatility index Transient time flowmeter Left ventricle

Rev Bras Cir Cardiovasc 2012;27(3):401-4

arterial variou de 8 a 106 ml/min, com média de 31,14 ml/ min, e nos enxertos venosos de 9 a 149 ml/min, com média de 50,42 ml/min.

Conclusão: O fluxômetro representa maior segurança para o cirurgião e para o paciente. Até mesmo sob o aspecto legal essa documentação dos enxertos pérvios evitará questionamentos futuros.

Descritores: Fluxômetros. Revascularização miocárdica.

Ponte de artéria coronária. Angina pectoris.

INTRODUCTION The low flow in arterial and venous grafts in coronary artery bypass grafting may represent a high risk of early occlusion with increased perioperative infarction and increased mortality. Some authors have reported early failures in the graft LITA 5% and saphenous vein up to 25% [1-5].

The presence of pulsatility in the grafts does not ensure patency thereof and may represent only high flow resistance.

Several methods have been described for early assessment of graft patency such as coronary tomography and angiography in early postoperative and use of intraoperative graft flow measurement systems.

The use of ultrasound TTFM (R) (transient time Flowmeter) directly over the graft provides data on the flow (ml / min), pulsatility index (PI) and percentage of diastolic flow in grafts that, taken together, allow to assess the patency therein. There are large number of publications in international literature standardizing data [6-10] and suggesting cutoff values to indicate revision of anastomosis. However, the literature lacks results in Brazilian patients.

METHODS Population studied In a group of 54 consecutive patients referred for CABG, we used the technique of intraoperative flow analysis using the Flowmeter (Medtronic Medi-Stim AS Inc).

Thirty-nine patients were male and 15 female, with ages ranging from 27 to 83 years, with a mean of 61.26 ± 11.0 years and a median of 60 years.

Among the comorbidities, we identified: hypertension in 42 patients, diabetes in 16, dyslipidemia in 24, smoking in 15, infarction in 24, obesity in 3, chronic obstructive pulmonary disease in 3, non-dialysis renal failure in 3.

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With respect to characteristics related to coronary disease, we observed three patients with lesion of the left coronary artery, 15 patients in functional class (FC) I or II angina and 39 with class III or IV (Canadian Cardiovascular Society), five patients had previously placed stent.

Ventricular function was normal or moderately impaired was assessed in 48 patients by ventriculography in the hemodynamic study and six had severe dysfunction of the left ventricle (LV), and two arrived in the operating room with intra-aortic balloon. Thirty-seven (68.5%) patients underwent surgery with cardiopulmonary bypass (CPB) and 17 without CPB (31.5%).

Surgical technique After sternotomy and exposure of the heart, heparinization was performed with 4 mg / kg in patients operated with CPB. Cannulation of the ascending aorta and single venous cannula was performed. CPB was started in normothermia and performed with aortic clamping with antegrade hypothermic blood cardioplegia. The off-pump patients were heparinized with 2 mg / kg and it was employed in all the preconditioning technique previously described [12]. The left internal thoracic artery was used in 48 (88.8%) patients. The CPB time ranged from 40 to 160 minutes, with an average of 80.18 minutes, anoxia time ranged from 18 to 90 minutes, with an average of 58.16 minutes.

At the end of the operation, with the patient off -pump and before protamine infusion, measurements were taken with the Flowmeter (Medtronic Medi-Stim AS Inc), with the same procedure adopted for off-pump patients. Upon finding that the grafts were functioning normally, it was administered protamine and further steps with the Flowmeter before closing the patient.

The equipment used consisted of a permanent console and disposable probes with the possibility of up to 50 uses each. The measurement was used by positioning the probe so as to engage the graft, obtaining measurements in real time on the screen of the device.

Succi JE, et al. - Intraoperative coronary grafts flow measurement using the TTFM flowmeter: results from a domestic sample

The measurement with Flowmeter was performed with 3 mm probes for the left internal thoracic artery and with 4 mm probes for the saphenous vein grafts. The graft was considered patent if the three parameters were adequate: the flow in the graft, the PI and the diastolic filling (DF%).

Flow curve - represents the flow (run-off) through the coronary artery, it is always coupled to the flow electrocardiogram and shows systolic, diastolic and mean flow. The flow rate can be altered by several factors: average artery pressure, coronary bed quality, size of native coronary artery spasms in the graft and / or possibly even in the coronary artery. A low flow does not necessarily represent involvement of the anastomosis.

Diastolic Filling Percentage (% DF) - Recent studies [8,9] suggest that diastolic filling represents the most important indicator of graft patency. It is obtained through the full diastolic flow divided by the systolic flow + diastolic flow: DF % = S Total Diastolic Flow / Systolic Flow + Diastolic Flow.

In summary, the percentage of diastolic filling of the coronary artery shall be greater than 60% in most grafts.

The quantification of diastolic filling is important in situations of low flow, averaging less than 10 ml / min.

The pulsatility index (PI) - is an absolute number obtained by the difference between the maximum flow and minimum flow divided by average flow: PI = Maximum Flow - Minimum Flow / Medium Flow. It shall range from 1 to 5, values above 5 represent problems with the coronary graft anastomosis.

Statistical method A comparison of the flux between the arterial and venous grafts was performed with non-parametric test and MannWhitney test. The comparison between the three vein grafts used in different territories was performed with the nonparametric Kruskal-Wallis.

Rev Bras Cir Cardiovasc 2012;27(3):401-4

DISCUSSION With the development of coronary artery bypass grafting without cardiopulmonary bypass [12] and / or minimally invasive, concern about the quality of anastomoses has become ever present.

The Flowmeter is a simple, easy and fast method, providing immediate information on the conditions of the coronary anastomosis.

The assessment of coronary grafts flow in the intraoperative or immediate postoperative period can be carried out in several ways: electromagnetic or Doppler angiography [6-8.13].

In the present study, the flow of the internal thoracic artery was significantly lower than the flow of saphenous vein grafts.

The flow of venous grafts was not influenced by the different coronary territories: diagonal artery, posterior interventricular artery and left circumflex artery.

In two (3.7%) patients (one artery and one vein graft), it was found that fluxes below 8 ml / min with PI above 5. The anastomoses were revised and the flowmetry was normalized.

Di Gianmmarco [9] studied 157 patients using Flowmeter, with identification of up to 3% of anastomoses at risk, and concluded to be an easy and effective method for the evaluation of the graft.

Louagie et al. [7] reported Flowmeter with 900 grafts analyzed and identified seven (2%) patients with altered flow curve, with low diastolic filling and high PI, requiring that the anastomosis was redone.

CONCLUSION The Flowmeter is safer for the surgeon and for the patient, ensuring that the operation was technically well done. Even under the legal aspect, that documentation of patent grafts avoids future questions.

RESULTS Initially, we compared the flow in arterial and venous grafts and found that in arterial grafts varied from 8 ml / min to 106 ml / min, with a mean of 31.14 ± 18.13 ml / min, and a median of 27.5 ml / min, whereas in vein grafts, the flow ranged from 9 to 149 ml / min, with a mean of 50.42 ± 28.42 ml / min and a median of 44 ml / min (P <0.0001). We compared the pattern of saphenous vein graft in three different areas: diagonal, posterior interventricular artery and the right coronary artery marginal left. The average flux for the diagonal was 49.38 ± 23.11 ml / min for the posterior interventricular branch 46.11 ± 12 ml / min and left marginal arteries, 51.84 ± 28.21 ml / min ( P = 0.789).

REFERENCES 1. Mustafa RM, Verazain JVHQ, Cavalcante MA, Pacheco FC, Ebaid HIA, Jorge PH, et al. Análise da resistência vascular coronariana e do fluxo sanguíneo dos enxertos venosos em revascularização do miocárdio. Rev Bras Cir Cardiovasc.

2009;24(2):200-4.

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2. Cerqueira Neto FM, Guedes MAV, Soares LEF, Almeida GS, Guimarães ARF, Barreto MA, et al. Fluxometria da artéria torácica interna esquerda na revascularização da artéria descendente anterior com e sem circulação extracorpórea. Rev Bras Cir Cardiovasc. 2012;27(2):283-9.

8. Morota T, Duhaylongsod FG, Burfeind WR, Huang CT. Intraoperative evaluation of coronary anastomosis by transittime ultrasonic flow measurement. Ann Thorac Surg.

2002;73(5):1446-50.

3. Goldman S, Copeland J, Moritz T, Henderson W, Zadina K, Ovitt T, et al. Improvement in early saphenous vein grafts patency after coronary artery bypass surgery with antiplatelet therapy: results of a Veterans Administration Cooperative Study. Circulation. 1988;77(6):1324-32.

4. Rasmussen C, Thiis JJ, Clemmensen P, Efsen F, Arendrup HC, Saunamäki K, et al. Significance and management of early graft failure after coronary bypass grafting: feasibility and results of acute angiography and re-re-vascularization. Eur J Cardiothoracic Surg. 1997;12(6):847-52.

5. Calafiore AM, Teodori G, Di Giammarco G, Vitolla G, Maddestra N, Paloscia L, et al. Multiple arterial conduits without cardiopulmonary bypass: early angiographic results.

Ann Thorac Surg. 1999;67(2):450-6.

6. Canver CC, Dame NA. Ultrasonic assessment of internal thoracic artery graft flow in the revascularized heart. Ann Thorac Surg. 1990;58(1):135-8.

7. Louagie YA, Haxhe JP, Jamart J, Buche M, Schoevaerdts JC. Intraoperative assessment of coronary artery bypass grafts using a pulsed Doppler flowmeter. Ann Thorac Surg.

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9. Di Giammarco G. Formal flow in coronary surgery. In: D'Ancona G, Karamanoukian HL, Ricci M, Salerno T, Bergsland J, eds. Intraoperative graft patency verification in cardiac and vascular surgery. Armonk: Futura Publishing; 2001. p.121-42.

10. Kieser TM, Rose S, Kowalewski R, Belenkie I. Transit-time flow predicts outcomes in coronary artery bypass graft patients: a series of 1000 consecutive arterial grafts.?Eur J Cardiothorac Surg. 2010;38(2):155-62.

11. Tokuda Y, Song MH, Oshima H, Usui A, Ueda Y. Predicting midterm coronary artery bypass graft failure by intraoperative transit time flow measurement.?Ann Thorac Surg.

2008;86(2):532-6.

12. Succi JE, Gerola LR, Succi GM, Almeida RA, Novais LS, Rocha B. Ischemic preconditioning influence ventricular function in off-pump revascularization surgery. Arq Bras Cardiol. 2010;94(3):319-24.

13. Calafiore AM, Giammarco GD, Teodori G, Bosco G, D'Annunzio E, Barsotti A, et al. Left anterior descending coronary artery grafting via left anterior small thoracotomy without cardiopulmonary bypass. Ann Thorac Surg.

1996;61(6):1658-63.

ORIGINAL ARTICLE

Rev Bras Cir Cardiovasc 2012;27(3):405-10

Influence of fresh frozen plasma as a trigger factor for kidney dysfunction in cardiovascular surgery Plasma fresco congelado como fator de risco para a disfunção renal no pós-operatório de cirurgia cardiovascular

Valdir Carlos Parreiras1, Isabella de Sá Rocha2, Antônio Sérgio Martins3, Enoch Brandão de Souza Meira4, Fábio Papa Taniguchi5

DOI: 10.5935/1678-9741.20120069

Abstract Objective: Kidney dysfunction is a major complication in the postoperative cardiac surgery setting. Operative risk factors for its development are cardiopulmonary bypass, anemia, antifibrinolytic drugs and blood transfusion. The objective of this study was to identify the risk factors for developing kidney dysfunction in patients undergoing cardiac surgery.

Methods: Ninety-seven patients were studied and 84 were analyzed. The sample was stratified into two groups. A serum creatinine higher than 30% compared to the preoperative period was considered for the kidney dysfunction group (n=9; 10.71%). There also was a control group when the increase in serum creatinine remained lower than 30% (n=75; 89.28%).

Results: It was observed that intraoperative transfusion of fresh frozen plasma in the control group was 2.05 ± 0.78 units and 3.80 ± 2.16 units in the kidney dysfunction group with P= 0.032.

1. Master in Health Sciences by IAMSPE, São Paulo, SP, Brazil.

2. Student of the Graduate Program in Health Sciences – IAMSPE, São Paulo, SP, Brazil.

3. PhD in surgery at UNESP. Department of Cardiovascular Surgery Faculty of Medicine of Botucatu-UNESP, Botucatu, SP, Brazil.

4. Director of the Department of Cardiovascular Surgery, Hosp.

Serv. Public State of São Paulo – IAMSPE, São Paulo, SP, Brazil.

5. Post-Doctorate in Thoracic and Cardiovascular Surgery, USP. Cardiovascular Surgeon Hosp. Serv. Public State of São Paulo – IAMSPE, São Paulo, SP, Brazil.

RBCCV 44205-1400 Conclusion: It was possible to associate that fresh frozen plasma transfusion is a risk factor for postoperative kidney dysfunction after cardiovascular surgery.

Descriptors: Renal insufficiency. Extracorporeal circulation. Plasma. Hemostasis.

Resumo Objetivo: A disfunção renal é uma complicação importante no cenário de pós-operatório de cirurgia cardiovascular. Como fatores de risco conhecidos no intraoperatório para o seu desenvolvimento destacam-se a circulação extracorpórea, a hemodiluição, drogas antifibrinolíticos e a transfusão sanguínea. O objetivo deste estudo é identificar os fatores de risco na transfusão de sangue e derivados para o desenvolvimento de disfunção renal em pacientes submetidos à cirurgia cardiovascular.

Métodos: Noventa e sete pacientes foram estudados e 84 foram analisados. A amostra foi estratificada em dois grupos,

Work carried out at Hospital Serv. Public State of São Paulo - IAMSPE, São Paulo, SP, Brazil.

Correspondence address: Fábio Papa Taniguchi Rua Itapeva 202, conj 91 – São Paulo –SP – Zip code 01332-000 E-mail: taniguchi@sbccv.org.br Article received on March 6th, 2012 Article accepted on August 14th, 2012

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Abbreviations, acronyms & symbols CG CPB FFP MAP PreCr RDG

Control group Cardiopulmonary bypass Fresh frozen plasma Mean arterial pressure Preoperative serum creatinine Kidney dysfunction group

sendo que o incremento de 30% na creatinina sérica no pósoperatório foi considerado para o grupo com disfunção renal (n = 9; 10,71%). O grupo não disfunção renal foi caracterizado

INTRODUCTION Despite recent advances in cardiovascular surgery kidney dysfunction is highly prevalent [1-8]. When dialysis is performed the mortality rate is increased by up eight times [9]. Kidney dysfunction is an independent risk factor for mortality in cardiovascular surgery and modifiable factors for its development should be monitored and performed before it occurs. Among these factors, the duration of cardiopulmonary bypass (CPB) [10] intraoperative anemia [11,12] and antifibrinolytic drugs [13,14] are variables set in the mechanism of kidney injury.

Cardiopulmonary bypass is associated with haemostatic dysfunction [15] induced by a decrease of coagulation factors. The abnormality triggered by the CPB has the potential to generate increased intraoperative bleeding that is associated with kidney dysfunction by speculative mechanisms such as hypotension and kidney ischemia [16-18].

In this scenario, transfusion of packed red blood cells, platelets and fresh frozen plasma (FFP) may be needed [19].

Transfusion of blood and blood products activate inflammatory mechanisms; increase oxidative stress; activates leukocytes and triggers the coagulation cascade [20,21]. The aim of this study is to analyze the risk factors for kidney dysfunction in cardiovascular surgery.

METHODS We evaluated patients undergoing cardiovascular surgery with CPB from November 2008 to March 2009. The local Ethics Committee approved the study (CAAE: 0048.0.338.338-08). Exclusion criteria were age less than 18 years and preoperative kidney failure requiring dialysis.

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pela creatinina sérica, que permaneceu inferior a aumento de 30% no pós-operatório (n = 75; 89,28%).

Resultados: Foi observado que a transfusão de plasma fresco congelado no grupo não disfunção renal foi de 2,05 ± 0,78 unidades e 3,80 ± 2,16 unidades no grupo disfunção renal com P= 0,032.

Conclusão: Foi possível associar, nesta série de pacientes, que a transfusão de plasma fresco congelado foi um fator de risco para disfunção renal pós-operatório de cirurgia cardiovascular.

Descritores: Insuficiência renal. Circulação Extracorpórea.

Plasma. Hemostasia.

Induction and maintenance of anesthesia were performed according to anesthesiologist assistant preference. No defined pharmacological protocol was mandatory.

In the operating room, continuous electrocardiograph was performed by monitoring by DII and V5 with oximetry and capnography (DX-7100, Dixtal, São Paulo, SP, Brazil).

Mean arterial pressure (MAP), obtained by puncturing the radial artery and central venous line in the right subclavian vein were standard. We used a digital thermometer (UM62009, Braile Biomedica, São José do Rio Preto, SP, Brazil) in the evaluation of the nasopharyngeal temperature.

Anticoagulation was achieved with heparin to maintain the activated clotting time exceeding 480 seconds. The CPB circuit was filled with 1.8 L of lactated Ringer’s solution, 50 ml of 20% mannitol, 10 ml of calcium gluconate 10%, 10 ml of magnesium sulfate to 10%, 500 mg of hydrocortisone, cefuroxime 750 mg and 5000 IU of heparin.

During CPB, hypothermia was performed at 32°C, nonpulsatile blood flow of 2.4 L/min/m2 and perfusion pressure between 60 and 80 mmHg. Myocardial protection was achieved with intermittent anterograde hyperkalemic blood cardioplegia. In the process of weaning from CPB, MAP was maintained above 65 mmHg. External pacemaker supported the heart when the rate was less than 70 bpm.

Dobutamine was administered routinely, with an initial dose of 3 mg/kg/min. Noradkidneyine was used if the MAP was less than 65 mmHg. Protamine was administered (1 mg per 100 IU of heparin). Prophylactic antibiotic therapy was performed with cefuroxime for 48 hours postoperatively.

The analyzed variables were age, weight, body mass index, sex, CPB time, anoxia, type of surgery, transfusion of packed red blood cells and blood products, postoperative drainage in 12 and 24 hours, presence of hypertension,

Parreiras, VC et al. - Influence of fresh frozen plasma as a trigger factor for kidney dysfunction in cardiovascular surgery

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diabetes mellitus, peripheral vascular disease and myocardial infarction.

The preoperative serum creatinine (PreCr) was determined before surgery. The postoperative serum creatinine was assessed at 1, 2, 5 and 7 days postoperatively.

mellitus was reported in 36.9%, cerebrovascular accident in 10.71%, chronic obstructive pulmonary disease in 13.09% of the patients. Valvular surgery was performed in 28.57% of the patients.

Table 1 shows the characteristics of each group. Table 2 presents surgical data. Respectively, Table 3 and Table 4 present transfusion of red blood cells, FFP and platelets units intraoperatively and in the postoperative period. As presented in Table 3 the median of the number of units of FFP used intraoperatively in the control and kidney dysfunction group was 2 (p25: 2; p75: 2) units, in the control group, and 3 (p25: 2; p75: 6) units in the kidney dysfunction group (P = 0.032).

Group stratification Patients were stratified into two groups, kidney dysfunction group (RDG) when the increase in serum creatinine was greater than 30% in the postoperative followup and control group (CG) when there was no increase in serum creatinine greater than 30% following postoperatively.

Statistical analysis The chi-square or Fisher’s exact test was used for the analysis of qualitative variables. The Mann-Whitney test was used to compare non-Gaussian distribution variables.

Analysis of variance for two-factor repeated measures analysis with Bonferroni post-hoc analysis was used in serum creatinine within each group. The significance level was set at 5%. We used the statistical analysis program SPSS® version 11.0 (SPSS, Chicago, IL, USA).

RESULTS Ninety seven patients were interviewed. Of these, one did not adhere to the study protocol. Eighty four patients were analyzed because 12 (12.5%) patients died before the end of the designed protocol and were further excluded.

Patients were divided into control group (CG) (n = 75) and renal dysfunction group (RDG) (n = 9). There was a greater concentration of men (64.2%) who underwent coronary artery bypass grafting (71.43%) and with history of acute myocardial infarction (53.57%). Previous history of diabetes

Table 1. Characteristics of the groups.

CG Age (years) 65.17±12.17 Weight (kg) 71.9±10.54 26.35±3.44 BMI LVEF 0.53±0.16 Male 49 Female 26 52% Previous MI 36% DM CVA 13.6% PVD 7.1% COPD 14% 69.3% High Blood Pressure 29.33% Valve CABG 70.6%

RDG 64.44±9.1 73.44±11.82 27.2±2.98 0.51±0.27 5 4 66.6% 80% 0 0 28% 44.46% 22.22% 77.7%

P 0.315 0.268 0.496 0.452 0.235 0.494 0.719 0.587 0.955 0.346 0.152 0.955

CG: control group; RDG: kidney dysfunction group; BMI: body mass índex; LVEF: left ventricule ejection fraction; MI: myocardial infarction; DM: diabetes mellitus; CVA: cerebrovascular accident; PVD: peripheric vascular disease; COPD: chronic obstructive pulmonary disease; VALVE: valve surgery; CABG: coronary artery bypass graft surgery

Table 2. Surgical data.

Euroscore (%) CPB (mim) Cross-clamp (min) Hematocrit (%) Troponin (ng/ml) Lactate (mmol/L) Dobutamine(mg/kg/min) Noradrenaline(mg/kg/min) ICU days Drainage 12h (ml) Drainage 24h (ml)

CG 4.12 ± 0.82 82.41 ± 29.52 66.26 ± 24.71 31.43 ± 4.20 3.31 ± 2.65 3.84 ± 3.36 6.62 ± 4.06 0.12 ± 0.08 3.64 ± 1.83 522.86 ± 390.34 827.07 ± 553.52

RDG 4.28 ±0.92 76.33 ± 20.74 59.44 ± 19.96 29.91 ± 2.92 3.12 ± 2.48 2.94 ±1.47 7.82 ± 3.38 0.11 ± 0.06 3.11 ± 1.27 438.89 ± 207.33 705.56 ± 468.67

P 0.597 0.379 0.341 0,506 0.237 0.186 0.227 0.877 0.192 0.409 0.114

CG: control group; RDG: kidney dysfunction group; CPB: cardiopulmonary bypass time; hematocrit: hematocrit in the immediate PO; lactate: serum lactate in the immediate PO; dobutamine: dobutamine infusion in the immediate PO; noradrenaline: noradrenaline infusion in the immediate PO; ICU: intensive care unit length stay; drainage: chest tube drainage

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Table 3. Transfusion of red blood cells, fresh frozen plasma and platelets units during surgery.

CG RDG P 2 (1 – 2) 3 (1.75 – 6.50) 0.857 Red cell 2 (2 – 2) 3 (2 – 6) 0.032 FFP 6 (5 – 7.25) 10 (0 – 6) 0.135 Platelets

Transfusion of FFP is indicated when coagulopathy develops in cardiovascular surgery. However, there is no consensus for its use since cardiovascular teams depends highly in their experience and judgment for FFP transfusion.

As expected, there is recognized variability transfusion rates in different surgical teams [27]. The Multicenter Study of Perioperative Ischemia Epidemiology II that was conducted in 16 countries in North America, South America, Europe and the Middle East showed that transfusion of FFP varied from 0 to 98%, platelets from 0 to 51% and red blood cells 9 to 100% among different centers [28]. The study Plasmacard, with data of French institutions, showed that 60% of patients with bleeding risk received FFP in an average volume of 7.14 ml kg to 20.87 ml/kg, in different centers. In this study, patients who developed kidney dysfunction received 3.18 ± 2.17 compared to 2.05 ± 0.78 units of FFP in those who did not. Bleeding volume, in a 24 hour period, was 827.07 ± 553.52 ml, in the control group, and 705.56 ± 468.47 ml in those who developed kidney dysfunction. One randomized clinical trial, with 40 patients, evaluated the effect of transfusion of 2 units of FFP prophylactic for bleeding in the cardiovascular surgery setting. The results showed that patients who received the two units of FFP had a postoperatively bleeding volume of 602 ± 180 ml versus 547 ± 113 ml who did not (P <0.05). Another study randomized 50 patients for 3 units of FFP or not at the end of surgery. There was no statistical difference between the groups in the postoperative period since bleeding volume averaged 896 ± 104 ml, in the group that received FFP, versus 776 ± 76 ml in the placebo group. Finally, there was no evidence that the prophylactic use of FFP in cardiovascular surgery decreased postoperative bleeding in a meta-analysis of six randomized trials involving 372 patients [29].

It must be considered that transfusion of FFP is not innocuous since infectious diseases can be transmitted and there is an increased risk for infection. Also, acute lung injury is related to the practice of blood products transfusion [29]. FFP transfusion is indicated when nonsurgical bleeding occurs as a coagulation disorder induced

by CPB. In this situation, FFP is able to provide coagulation factors that were consumed after CPB, such as, the Leiden factor, factor XI, factor XIII, plasminogen and S protein.

Also, CPB contributes to the systemic inflammatory response since endotoxemia, ischemia reperfusion injury, surgical trauma and the non-endothelial surfaces of CPB are harmful components. These phenomena affect kidney function with consequent impact on glomerular filtration.

Intraoperative bleeding in cardiovascular surgery by coagulopathy is also associated with the thrombogenic surfaces of CPB, hemodilution, hypothermia and heparin.

The net result is that the complement system is activated; fibrinogen and platelets decrease with intensification of

Data presented as median and percentiles 25 - 75. FFP: fresh frozen plasma units; CG: control group; RDG: kidney dysfucntion group

Table 4. Transfusion of red blood cells, fresh frozen plasma and platelets units in the post-operative period.

CG RDG P 2 (1 – 4) 2 (1.25 – 5) 0.352 Red cell 3 (1.5 – 4.5) 3 (0 – 2) 0.093 FFP 2 (2 – 3.75) 6 (6 – 6) 0.476 Platelets Data presented as median and percentiles 25 - 75. FFP: fresh frozen plasma units; CG: control group; RDG: kidney dysfucntion group

DISCUSSION In this study we could observe the association of transfusion of FFP as a risk factor for kidney dysfunction in cardiovascular surgery.

When kidney dysfunction occurs in the postoperative period of cardiovascular surgery it is a severe event that determines increase morbidity and mortality. It is believed that up to 30% of patients undergoing cardiovascular surgery develop kidney dysfunction [20]. In these patients the need for dialysis occurs in 1% to 2%, with a mortality rate of 30 to 70% [22,23].

Different variables are associated with kidney injury in cardiac surgery. Sex, diabetes mellitus, hypertension, age, previous kidney dysfunction, reoperation, peripheral vascular disease and left ventricular dysfunction in addition to variables related to the surgery itself as valve surgery, cardiopulmonary bypass time, hypotension and intraoperative anemia [10,12,24].

Transfusion of packed red blood cells is a relevant debate in cardiovascular surgery since indications for routine blood transfusion have been improved [12,24,25].

However, the transfusion of FFP is a topic without relevant discussion. Transfusion of blood and its products are related to preoperative anemia, weight, sex, anticoagulant or antiplatelet therapy and type of surgery. When evaluated the intraoperative factors that triggers transfusion of FFP it must be considered: previous heart surgery, thrombocytopenia, history of gastrointestinal bleeding, left ventricular dysfunction and preoperative use of heparin are noticed [26].

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the inflammatory phenomena. The coagulation cascade up regulates thrombin generation, intensified by the complement system, that results in a coagulation disorder associated with endothelial dysfunction by CPB and finally fibrinolysis with increased intraoperative bleeding.

FFP is indicated for coagulopathy, however bioactive substances in it such as histamine, eosinophil cationic protein, protein X, myeloperoxidase, and plasminogen activator inhibitor [30] enhance immune response and inflammatory processes. It is considered that the presence of antibodies may react with human leukocyte antigen and activation of the complement system, since endothelial damage and activation of neutrophils [31] are associated with CPB triggering kidney injury.

7. Thourani VH, Keeling WB, Sarin EL, Guyton RA, Kilgo PD, Dara AB, et al. Impact of preoperative renal dysfunction on long-term survival for patients undergoing aortic valve replacement. Ann Thorac Surg. 2011;91(6):1798-806.

CONCLUSION Although this particular scenario suggests a multifactorial etiology for kidney dysfunction in cardiovascular surgery, it was possible, in this series of patients, to associate the transfusion of FFP as a risk factor for kidney dysfunction.

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ORIGINAL ARTICLE

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Time of arrival of patients with acute myocardial infarction to the emergency department Tempo de chegada do paciente com infarto agudo do miocárdio em unidade de emergência

Alessandra Soler Bastos1, Lúcia Marinilza Beccaria2, Ligia Márcia Contrin2, Cláudia Bernardi Cesarino3

DOI: 10.5935/1678-9741.20120070 Abstract Objectives: To characterize the profile of patients with acute myocardial infarction (AMI) treated at the emergency department and to verify the time of arrival of each patient (∆T). Identify how the patient was transported and to correlate Delta-T (∆T) with the treatment and the prognosis of each patient.

Methods: Cross-sectional survey involving 52 patients with AMI admitted to the Emergency Department of a Teaching Hospital took part in the study from July to December 2010. Data collection was performed using medical records and interviews.

Results: The majority of the patients were male with a mean age of 62.35 ± 14.66 years. The participants were married, with low education levels, family history of heart diseases, arterial hypertension, dyslipidemia, and a sedentary lifestyle. The symptoms presented were pains in the chest, epigastric region, or a chest discomfort associated to dyspnea and/or sudden sweating. The majority of the

1. São José do Rio Preto Medical School (FAMERP), Approved at Intensive Therapy Improvement Course at Hospital de Base, São José do Rio Preto, SP, Brazil.

2. Full Professor at Specialized Nursering Department at FAMERP, São José do Rio Preto, SP, Brazil.

3. Full Professor at General Nursering Department at FAMERP, São José do Rio Preto, SP, Brazil.

This study was carried out at São José do Rio Preto Medical School, São José do Rio Preto, SP, Brasil

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patients were transported by ambulance. They were submitted to cardiac catheterization followed by angioplasty.

Delta-T found was 9h45min ± 18h9min. In this study, the overall lethality was 3.85%.

Conclusions: The perception of signs and symptoms of AMI by the patient was a decisive factor when seeking out specialized treatment. Those with the lowest Delta-T presented better prognosis.

Descriptors: Myocardial infarction. Time. Emergency service, hospital.

Resumo Objetivo: Caracterizar o perfil das pessoas com infarto agudo do miocárdio (IAM) atendidas em um serviço de emergência e verificar o tempo de chegada (delta T).

Identificar como o paciente foi transportado e correlacionar o delta T com o tratamento e prognóstico do mesmo.

Correspondence address: Alessandra Soler Bastos Rua Gabriel Janikian, 211 – São José do Rio Preto, SP Brasil – CEP 15080-350 E-mail: lekasoler@hotmail.com

Scientific Initiation Scholarchip by FAMERP. Article received on January 18st, 2012 Article accepted on July 16th, 2012

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Abbreviations and acronyms CAD AMI LUL SST

Coronary artery disease Acute myocardial infarction Left upper limb Segment elevation

Métodos: Pesquisa transversal, incluindo 52 pacientes admitidos na Unidade de Emergência de um Hospital de Ensino com diagnóstico de IAM, no período de julho a dezembro de 2010. A coleta de dados foi realizada por meio do prontuário e entrevista.

Resultados: A maioria dos pacientes era do gênero masculino, com idade média de 62,35 ± 14,66 anos, casada,

INTRODUCTION Epidemiological data from major societies point cardiovascular diseases as those with increased mortality and morbidity [1,2]. There is expectation that in 2020, 40% of deaths are related to them. [3] According to American research, more than 12 million people have some heart disease and more than one million presents an acute myocardial infarction (AMI) per year, resulting in 466,000 deaths related to coronary artery disease (CAD) [4]. In Brazil, cardiovascular diseases are responsible for 31% of deaths from known causes [5] and in this set, the AMI is worrying society and public health authorities, due to the impact on mortality and the number of hospitalizations in whole country [6,7], being the major cause of attendance in emergency units [4].

Two-thirds of sudden deaths from heart disease occur outside the hospital and only 20% of people who reported acute chest pain to the emergency arrive two hours before the start of these signals [6,8]. One factor that contributes to the reduction of this high mortality from AMI is the rapid treatment of these patients after the onset of symptoms [6].

Therefore, it is necessary to prepare the emergency services and the professionals involved, so that the care be guided and the diagnosis accurate. [3] Studies indicate that, in Brazil, patients with symptoms of MI did not immediately seek health services, by not 412

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poucos anos de estudo, histórico familiar de doença cardíaca, hipertensão arterial, dislipidemia e sedentarismo. Os sintomas apresentados foram dor no tórax, região epigástrica ou desconforto torácico associado à dispneia e/ou sudorese súbita. A maioria dos pacientes foi transportada por ambulância e submetida a cateterismo cardíaco, seguido de angioplastia. O delta T encontrado foi 9h54min ± 18h9min.

A letalidade global do estudo foi de 3,85%.

Conclusão: O reconhecimento dos sinais e sintomas do IAM pelo paciente foi fator determinante para a procura de atendimento especializado e aqueles com menor delta T apresentaram melhor prognóstico.

Descritores: Infarto do miocárdio. Tempo. Serviço hospitalar de emergência.

recognizing its symptoms, because there is no specialized services and first aid and even due to a poor public transportation, making difficult the arrival of these people to the hospital. [8] These obstacles are challenges of public health authorities, because the AMI is considered a longterm illness, demanding actions, procedures, healthcare services and, consequently, higher costs, and causing huge losses to society [5,8].

The knowledge of the arrival time of patients with symptoms of AMI to specialized services, as well as the identification of the difficulties faced by them, can subsidize nursing professionals and guidance to help patients, their families and the community [3,9]. Therefore, this study aimed to characterize the profile of people with AMI treated in an emergency department and check the arrival time (delta T). Identifying how the patient was transported and correlating the delta T with its management and prognosis.

METHODS Cross-sectional study in a teaching hospital in northeastern São Paulo, which provides services to different medical specialties, and is intended to provide health services, education and research. Data were collected at the Emergency Unit, where patients are admitted in critical health, accident victims, politraumas, cardiac arrests and other who require immediate care. The sample consisted of

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52 patients older than 18 years with AMI who were admitted to this unit during the period from July to December 2010.

We excluded patients younger than 18 years, those who did not agree to participate in the study and those with deficit or mental retardation.

Survey of the profile of patients with AMI was performed through hospital records, in accordance with the following sociodemographic and clinical variables: gender, age, marital status, weight, height, education, occupation, family history, origin, with whom the patient lives, smoking, hypertension, diabetes, dyslipidemia and exercise. An interview about arrival time (delta T), means of transport and treatment and prognosis after AMI. The research project was approved by the Research Ethics Committee of the São José do Rio Preto Medical School-FAMERP - Protocol No. 0176/2010.

For the statistical data of the epidemiological profile percentages were used, with statistical approach of chisquare test for qualitative variables, and univariate comparison tests, for quantitative variables, the MannWhitney and Kruskal-Wallis tests, all to the level of significance of 0.05.

Table 2. Risk factors presented by patients with AMI. São José do Rio Preto - SP, Brazil, 2011: percentage.

Clinical Variables N %

Table 1. Sociodemographic profile of patients with AMI. São José do Rio Preto - SP, Brazil, 2011: percentage.

Variables N % Gender Male 40 76.9 Female 12 23.1 Age (years) 30-59 22 42.3 60-90 30 57.7 Marital status Married 34 65.4 Widower 10 19.2 Single 8 15.4 Occupation Retired 24 46.2 Service care department 15 28.8 Housewife 7 13.5 Merchant 5 9.6 Unemployed 1 1.9 Schooling from 0 to 7 years 31 59.6 from 8 to 11 years 19 36.5 More than 11 years 2 3.9 BMI Overweight 18 40 Normal 16 35.6 Obesity 10 22.2 Malnutrition 1 2.2

Sedentary Hypertension Family History Dyslipidemia Smoking Overweight Previous CAD ** Diabetes Mellitus

43 40 30 24 19 18 14 11

82.79 76.92 57.69 46.15 36.54 40* 26.92 21.15

* Calculation performed with 45 patients, because 7 of them could not report weight and height; ** Coronary Artery Disease

RESULTS Regarding the socio-demographic profile (Table 1) of 52 patients with AMI, we observed: males (76.92%) with a mean age of 62.35 ± 14.66 years, married (65.38%), retired (46.15%), with a few years of study, overweight (40%), from the region of São José do Rio Preto (57.69%).

With regard to clinical aspects, the majority of patients reported a family history of heart disease (57.69%), hypertension (76.92%) and inactivity (82.79%) (Table 2).

Regarding symptoms, 31 (59.62%) patients were associated with chest pain or chest discomfort, pain radiating to the left upper limb (LUL) and dyspnoea and/or sudden sweating, 19 (36.54%), pain chest, LUL, epigastric or chest discomfort and only two (3.85%), dyspnea and/or sudden sweating. Of these, 32 (61.54%) patients remained with symptoms for more than 20 minutes, what motivated them to seek medical attention, and 36 (70.59%) were transported by the ambulance service to the county and 15 (29.41%) with the family car. With regard to the demand for other services before being treated at the emergency Teaching Hospital, it was found that 47 (90.38%) first sought treatment in the Basic Health Units.

About evolution of these patients in the hospital, it was found that 20 (39.22%) underwent cardiac catheterization followed by angioplasty, 19 (37.25%), only catheterization, seven (13.7%), catheterization followed by coronary artery bypass grafting and five (9.8%) underwent clinical treatment. Regarding prognosis, we found that 50 (96.2%) were discharged, while two (3.8%) died.

Taking into account the time (delta T) that patients with AMI spent to arrive in this emergency department, we observed mean ± 9h54min 18h9min, and delta T minimum was 23 minutes and the longest 96 hours (Table 3).

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Table 3. Descriptive statistics of the arrival time of a patient with AMI. São José do Rio Preto - SP, Brazil, 2011: time.

Variable N Md Min Max

Table 4 shows the P values for the associate chi-square test between the main variables. It was found that there was an association between hypertension and presentation of symptoms presented by patients and between prior CAD and symptoms at admission.

Most patients with high blood pressure (69.7%) presented association between all symptoms, while nonhypertensive patients (66.67%) reported chest pain, LUL, epigastric or chest discomfort, showing that a higher number of symptoms when compared to normotensive individuals.

With respect to patients with prior CHD, also reported symptoms at admission (71.43%). The association between CAD and prior symptoms shows that patients who have experienced an AMI or other coronary artery disease were able to identify symptoms early and go quickly to the emergency room.

In the association of prognosis in relation to selfmedication, patients who had a favorable clinical treatment were excluded from the analysis. Table 5 shows the percentage of prognosis in relation to self-medication. The data demonstrate that patients who self-medicated had worse outcomes when compared to those not selfmedicated.

In Table 6, we performed comparative assessment that has demonstrated the results of the variable delta T in relation to social and clinical characteristics of the patient and observed a significant association between delta T and the variables: symptoms on admission, progression and self-medication. When compared delta T and symptoms, means of transport and presence of accompanying or not, it was found that there is a significant association.

When comparting the delta T with symptoms on admission, prognosis and self-medication, there was a significant association between these variables (Tabela7).

Delta T 52

9h54min ± 18h9min

4h8min

23min

96h

Table 3 shows that the results of the arrival time of the patients had high discrepancy, showing a high coefficient of variation of around 183.33%, attributed to the very high values of time of arrival which influenced the mean value of the distribution, increasing it in relation to the median value, so the time of arrival presented asymmetric distribution.

In relation to pain intensity, on an analog scale of 0 to 10, where zero means no pain and 10 worst pain experienced, there was an average of 6.9 with a median of 8, assuming that the patients felt pain from median to high intensity, and 50% of them characterized their pain scores between 8 and 10.

Table 4. P values for the associative test between variables: smoking, hypertension, prior CAD, schooling, seeking for another service, escort, and self-medication and variables: symptoms present at admission and patient outcome. São José do Rio Preto - SP, Brazil, 2011.

Variables Characterization Variables response Symptoms present Symptoms At admission Evolution Smoking Hypertension Previous CAD Schooling Another service * Scort Self-Medication

0.259 0.05 0.782 0.5 0.024 0.217 0.712

0.066 0.359 <0.001 0.524 0.768 0.901 0.334

0.606 0.79 0.637 0.078 0.511 0.034

* Refers to Primary Care: Basic Health Unit and Emergency Care Unit

Table 5. Percentages of prognosis in relation to self-medication of patients with AMI. São José do Rio Preto - SP, Brazil, 2011.

Self Medication Prognosis Catheterization Catheterization and angioplasty Catheterization and CABG Total No 17 (53.13%) 12 (37.50%) 3 (9.38%) 32 (71.11%) Yes 2 (15.38%) 7 (53.85%) 4 (30.77%) 13 (28.89%) Total 19 (42.22%) 19 (42.22%) 7 (15.56%) 45 (100%) P Value = 0.034

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Table 6. Descriptive statistics of delta T for symptoms, marital status, prognosis, mode of transport, escort and self-medication of patients with AMI. São José do Rio Preto - SP, 2011, Brazil: number, time and P value.

Characteristics

N

Delta T

P

Symptoms

Pain and/or chest discomfort Pain and / or discomfort plus dyspnoea

19 31

14h14min ± 24h9min 7h21min ± 13h41min

0.284

Marital status

Married Single / Divorced Widower

34 8 10

11h31min ± 21h40min 4h1min ± 2h35min 9h5min ± 9h54min

0.042

Evolution

Catheterization Cat and Angioplasty Cat. and CABG

19 20 7

6h8min ± 13h4min 10h29min ± 16h42min 23h43min ± 33h2min

Transportation

Ambulance Car

36 15

7h42min ± 11h35min 15h34min ± 28h33min

0.444

Scort*

Yes No

40 12

10h29min ± 20h15min 7h56min ± 8h15min

0.427

Self Medication

Yes No

14 37

20h11min ± 28h40min 6h12min ± 10h38min

0.01

0.014

* Monitoring during transport of the patient to the unit

Table 7. Descriptive statistics of delta T and the pain score for the presence of symptoms on admission of patients with AMI. São José do Rio Preto - SP, 2011: time and P value.

Variables Symptoms on admission Min Md Max P Delta T

Pain score

Yes No

4h1min ± 5h17min 21h24min ± 29h36min

2h44min 6h11min

23min 41min

27h 96h

0.042

Yes No

7.33 ± 2.87 4.6 ± 4.25

8 5.5

0 0

10 10

0.069

DISCUSSION The majority of the study population was elderly, male, with a few years of study and living in neighboring municipalities of City where the emergency unit of the teaching hospital was located, which corroborates research on Dante Pazzanese risk score for acute coronary syndrome, that observed the older age associated with the occurrence of adverse coronary events, as well as the low level of education of patients [9].

Regarding risk factors, most patients had sedentary

lifestyle, hypertension, dyslipidemia and family history.

Studies on acute coronary syndrome report that most AMI patients had three or more risk factors and the most prevalent were: hypertension, dyslipidemia and family history, and physical inactivity showed no relevance [3,4].

In this study, physical inactivity was reported by 82.79% of patients and smoking by 36.54%, showing no significance when related to the studied variables.

The importance of time elapsed between the onset of AMI up to its care in an emergency department (delta T) is justified by the need for immediate reperfusion 415

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interventions, aiming at restoration of coronary blood flow, thus contributing to increased survival of these patients [10-12].

The delta T found in this survey was 9h54min ± 18h9min, much higher than reported in the study by Franco et al. [13] (2h55min ± 3h59min) and Muller et al. [11] (4h15min ± 2h7min). This fact can be explained by the fact that 84.61% of the patients are from other cities and 26.92% of them have self-medicated before seeking health care (P = 0.01).

However, observing the total number of patients residing in other locations, it was found that 31.8% of them are from the neighboring city, which is about 16 minutes drive from the emergency services investigated.

A study performed in Rio de Janeiro, involving patients diagnosed with AMI with ST segment elevation (SST) showed that 67.7% reached the emergency room after three hours of the onset of the first symptom and 8.4% after 12 hours [ 3]. Another study performed in Rio Grande do Sul showed that 88% of patients with SST sought emergency care within an hour, and the average was 3h59min to 2h55min. They also found that patients did not realize that the chest pain as a heart event took longer to arrive the health service than those who identified [13].

According to the Directive IV of the Brazilian Society of Cardiology on the Treatment of AMI [10], some factors contributing to the delay of the patient to seek help, such as: denial that that chest pain is of cardiac origin, association of pain with other pre-existing chronic conditions, lack of knowledge on benefits if quick care, urgent care not available to all patients. Other studies confirm that female patients with low socioeconomic status, and self-medicated with older age, take longer to arrive to specialized service [10.13].

In this study, we found that single or divorced patients had lower delta T when compared to married or widowed, which agrees with the study by Franco et al. [13], which also showed that married persons and widows had more time compared to single and divorced. However, there was no significant association between delta T and the variable marital status (P = 0.759), also observed in the study by Franco et al. [9] that showed P = 0.006. Data from a study comparing patients with AMI regarding their time of arrival at the emergency unit found that those who sought medical care for more than six hours, and were on average older (75 ± 7 years), women and non-whites [ 14].

Regarding symptoms, it was found that patients with chest pain radiating to LUL, epigastric region or chest discomfort showed higher delta T compared with those who reported these symptoms together with sudden dyspnea and sweating (P = 0.284). While there is no significance between this finding, it can be said that patients with higher symptoms, sought the emergency room faster than those with mild or moderate symptoms.

When the individual recognizes the signs and symptoms of AMI or has already undergone a previous experience of arterial disease, it significantly lowers the delta T [13].

Similarly, this study found that patients with prior CHD, showed lower delta T (4h56min ± 6h29min) and those who had not (11:56min ± 21:40min) (P = 0.646). Other research indicates that patients who take longer for the medical visit had higher prevalence of diabetes and previous angina, and less history of myocardial infarction, coronary angioplasty or cardiac surgery [14].

The association between prior CAD and symptoms at admission was present in 71.43% of patients (P <0.001), suggesting that they had knowledge of such a symptom and therefore arrived quickly to the emergency room.

Patients who believe their symptoms are related to their heart seek help more quickly than those who attribute their symptoms to other causes [15].

In a study performed on factors that influence the demand for emergency services by patients with AMI, 33% had symptoms as first decision facing the self-medication, and presented a delta T of 3h36min ± 2h24min. In this study, 26.92% of patients who self-medicated, with delta T from 20:11min ± 28h40min, while those not taking medication on their own showed lower delta T, but greater than the delta T from mentioned study of patients who selfmedicated. The P value for this comparison was 0.01, assuming the existence of significant differences between the arrival time and the attitude of self-medication.

It was found that patients who self-medicated had worse during hospitalization when compared to non selfmedicated. The first group progressed to cardiac catheterization followed by percutaneous coronary intervention (53.85%) or CABG (30.77%). The second group underwent cardiac catheterization (53.13%), indicating that patients who self-medicated, due to higher delta T, had worse outcomes during hospitalization than those who did not self-medicated and arrived at the hospital soon.

With respect to the means of transport used in the study of Muller et al. [11], 28.1% of patients were transported by ambulance and 57.5%, on their own, however, there was no time difference between them. The study by Franco et al.

[13] demonstrated that patients transported by ambulance had a higher delta T when compared to transported by car, data that are opposed to this study, in which 70.59% were transported by ambulance and car were 29.41%, being the delta T of patients transported by ambulance relatively smaller than the car. It was also found that most patients was accompanied by wife or child.

In an emergency situation, patients who call for an ambulance are dependent on many factors before being rescued, such as: ambulances are available, the distance to be traveled and patients living with other people who can call for help. [13] Being transported by ambulance was not

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significant for reducing the service time compared to those who were transported by car. [11] In this study, it was also not possible to verify significance (P > 0.05).

The delta T of patients referred by ambulance was lower than those transported by car. This fact can be explained by the fact that they seek for other health services, presenting a high delta T. On the other hand, with respect to patients who called for an ambulance, most first sought other health services and, by the presence of symptoms suggestive of AMI, professionals from such helth units headed for the emergency room, to perform diagnosis and treatment.

Regarding the treatment used for patients with AMI, it is known that this is time-dependent, according to the time between the first symptoms, care and therapy to be adopted [10]. It was found in this study, that patients undergoing only cardiac catheterization presented the delta T of 6h8min ± 13h4min. On the other hand, patients who underwent cardiac catheterization followed by percutaneous coronary angioplasty obtained delta T of 10:29min ± 16:42min and between those who had undergone catheterization followed by coronary artery bypass grafting the delta T was 23:43min ± 33h2min (P = 0.014).

It was observed that the time has a direct influence on the choice of treatment after patient admission. Thus, we can say that patients who do not receive immediate specialized care have a worse prognosis when compared to those who receive treatment quickly. In this study, most patients were discharged from hospital and only two has evolved into death (3.85%). Comparing the lethality with other studies, it was smaller tha that found (9.5% and 4.8%) [3,4].

In the present study, coronary artery bypass grafting was performed slightly (13.73%). In a similar study, there was agreement as to the percentage found (13.7%). In a study performed in Rio de Janeiro, the rate of CABG was 8%. One possible explanation for the low number of surgeries for the treatment of AMI, was the fact that patients are elderly, so with collateral circulation, and also by the surgical risk and complexity of the surgery. The use of drugs such as thrombolytic and nitrates, and coronary angioplasty are the best treatment options for these patients [3.16].

One of the most characteristic symptoms of AMI is the angina caused by myocardial ischemia, which is often severe and may be relieved by rest and nitrates. The symptom of chest pain is present in 75% to 85% of patients with AMI, which is the factor of greatest significance for these people to seek for help. [9] In this study, it was found that 96.15% of patients had angina, occurring an average score of 6.9 points, with a median of 8 points, demonstrating that these patients had pain of medium to high intensity.

The limitation of this study was the small sample size, which may have influenced the results, however, they

represent the patients treated in this emergency department during the study period.

CONCLUSION The profile of patients with AMI in this study were men, older, married, with a few years of study, retirees, presenting overweight, coming from the neighboring cities of the emergency unit of the teaching hospital studied. Regarding risk factors, most patients had a family history of heart disease, hypertension, dyslipidemia and physical inactivity.

The recognition of the signs and symptoms of AMI by the patient was determinant for seeking specialized care.

The symptoms presented were chest pain, epigastric or chest discomfort associated with dyspnea and/or sudden sweating. Most patients were transported by ambulance and underwent cardiac catheterization, followed by angioplasty. The delta T found was 9h54min ± 18h9min.

The overall mortality in the study was 3.85%.

It was found that patients undergoing only cardiac catheterization presented the lowest delta T (6h8min ± 13h4min) and those who underwent cardiac catheterization followed by coronary angioplasty or coronary artery bypass grafting had higher delta T (10:29min ± 16:42min and 23:43min ± 33h2min, respectively), or that is, patients with low delta T showed better prognosis.

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ORIGINAL ARTICLE

Rev Bras Cir Cardiovasc 2012;27(3):419-28

Replacement of pulmonary artery trunk in sheep using tubular valved heterograft in non-aldehydic preservation Substituição do tronco da artéria pulmonar em carneiros utilizando heteroenxerto tubular valvado com preservação não-aldeídica

Helmgton José Brito de Souza1, José Honório de Almeida Palma2, Ivan Sérgio Joviano Casagrande3, Sérgio Campos Christo4, Luiz Sérgio Alves-Silva5, Marco Antônio Cardoso de Almeida6, Diego Felipe Gaia7, Enio Buffolo8

DOI: 10.5935/1678-9741.20120071

RBCCV 44205-1402

Abstract Introduction: The cardiac bioprostheses are related to thromboembolic events, infectious and degenerative diseases. Wear is mainly attributed to the denaturation of collagen. Glutaraldehyde, the predominant method of preservation of bioprostheses, favors the calcification process and limits their durability. Several techniques try to contain the degenerative process of bioprostheses.

Objectives: To evaluate the process of calcification in vivo pulmonary valve heterografts preserved in non-aldehydic (L-Hydro®).

Methods: Seventeen sheep underwent replacement of the pulmonary artery valved tubular grafts of bovine

pericardium. The animals were divided into two groups: Group L-Hydro® (test / n = 14) and Group Glutaraldehyde (control / n = 3). About 150 days after implantation the animals were sacrificed, necropsied and implants subjected to a pathological study, radiological evaluation and measurement of calcium by atomic absorption spectrophotometry. Statistical analysis was obtained through the Fisher’s exact test, Student’s t or Mann-Whitney test (significance: 5%).

Results: The radiological evaluation, the macroscopic and microscopic measurement of serum calcium by atomic absorption spectrophotometry showed increased calcification of the prosthetic group Glutaraldehyde, when compared to

1. PhD in Cardiovascular Surgery, Surgeon, Federal University of São Paulo (UNIFESP), Paulo Medical School, São Paulo, SP, Brazil.

2. Tenured Professor, MD, Associate Professor of the Federal University of São Paulo (UNIFESP), Paulo Medical School, São Paulo, SP, Brazil.

3. Cardiovascular surgeon, Labcor Laboratory, Belo Horizonte, MG, Brazil.

4. Cardiovascular surgeon, Labcor Laboratory, Belo Horizonte, MG, Brazil.

5. Cardiologist.

6. Patologist.

7. PhD in Cardiovascular Surgery; Associate Professor at the Federal University of São Paulo (UNIFESP), Paulo Medical School, São Paulo, SP, Brazil.

8. Titular Professor of Cardiovascular Surgery, Federal University of São Paulo (UNIFESP), Paulo Medical School, São Paulo, SP, Brazil.

Work carried out at Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina, São Paulo, SP, Brazil, and Centro de Pesquisa Labcor Laboratório, Belo Horizonte, MG, Brazil.

Correspondence adress: Helmgton José Brito de Souza Rua Napoleão de Barros, 715 - 3º andar São Paulo, SP, Brazil – Zip code: 04024-002 E-mail: helmgton@uol.com.br Article received on January 29th, 2012 Article accepted on June 25th, 2012

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Abreviaturas, acrônimos e símbolos PEG SPSS UNIFESP

Polietilenoglicol Statistical Package for the Social Sciences Universidade Federal de São Paulo

denture-HydroR Group L (P = 0.001). Seven animals in Group L-Hydro® (50%) had adherence of the leaflets to the wall of the tube (P = 0.228).

Conclusions: Prostheses preserved in L-Hydro® were more resistant to calcification when compared with glutaraldehyde preserved.

Descriptors: Bioprosthesis. Glutaral. Polyethylene glycols. Heart valve prosthesis. Heart valve diseases/surgery.

Resumo Introdução: As biopróteses valvares cardíacas estão relacionadas a eventos tromboembólicos, infecciosos e degenerativos. Seu desgaste é atribuído principalmente à desnaturação do colágeno. O glutaraldeído, método predominante de preservação de biopróteses, favorece o processo de calcificação e limita sua durabilidade. Diversas técnicas tentam conter o processo degenerativo das biopróteses.

INTRODUCTION Patients with heart valve disease, surgical treatment when indicated, deal with an important and sensitive issue - the choice of valve replacement. The existing substitute valve, however, has significant limitations. Because they are foreign tissue to the human body, valve prostheses are associated with the risk of thromboembolic complications, degenerative and infectious diseases [1]. While mechanical prostheses, highly thrombogenic, requires long-term anticoagulant therapy, the bioprostheses, whether cryopreserved or fixed in glutaraldehyde, have limited durability dysfunction caused mainly by progressive tissue degeneration. The degeneration of bioprostheses continues to figure among the main issues surrounding the treatment of patients with valvular heart disease. The search for the manufacture of valve replacement through tissues has been 420

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Objetivo: Avaliar o processo de calcificação, in vivo, de heteroenxertos pulmonares valvados, preservados em meio não-aldeídico (L-Hydro®).

Métodos: Dezessete carneiros foram submetidos à substituição do tronco da artéria pulmonar por enxerto tubular valvado de pericárdio bovino. Os animais foram distribuídos em dois grupos: Grupo L-Hydro® (teste / n=14) e Grupo Glutaraldeído (controle /n=3). Cerca de 150 dias pós-implante os animais foram sacrificados, necropsiados e as próteses submetidas a estudo anatomopatológico, avaliação radiológica e dosagem do cálcio por espectrofotometria de absorção atômica. A análise estatística foi obtida por meio dos testes exato de Fisher, T de Student ou Mann-Whitney (significância: 5%).

Resultados: A avaliação radiológica, macroscopia, microscopia e dosagem de cálcio por espectrofotometria de absorção atômica demonstraram maior calcificação nas próteses do Grupo Glutaraldeído, quando comparadas às próteses do Grupo L-Hydro® (P=0,001). Sete animais do Grupo L-Hydro® (50%) apresentaram aderência das cúspides à parede do tubo (P=0,228).

Conclusões: As próteses preservadas em L-Hydro® demonstraram-se mais resistentes à calcificação, quando comparadas às preservadas em glutaraldeído.

Descritores: Bioprótese. Glutaral. Polietilenoglicóis.

Próteses valvulares cardíacas. Doenças das valvas cardíacas/ cirurgia.

the subject of studies by many authors over the last sixty years [2-8]. In an attempt to reduce the wear rate and thus prolong the life of prostheses, some preservation techniques have been proposed in order to reduce the calcification process [9-15]. The bioprostheses commonly are preserved in glutaraldehyde. This method is associated with greater aggregation of fibrin, macrophages, calcium, and thrombotic material to the surface of the prosthesis [16,17]. Glutaraldehyde contained on the surface of the prosthetic tissue is cytotoxic. The main disadvantage of glutaraldehyde fixation of bioprostheses is the resulting tissue calcification over time [1,16,17], which favors the dysfunction and the need for surgical replacement of the prosthesis. The current challenge of tissue engineering is to study and propose the creation of replacement tissue and heart valves from biological and artificial structures that are biocompatible, non-thrombogenic, non-teratogenic,

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durable and permit monitoring of the growth of the host [18-20]. Theoretically, the alternative would be to use the prosthesis, treated, allow spontaneous epithelialization with host cells [21].

Nina et al. in 2005 [22] and Santos et al. in 2007 [23] tested the method of preservation in L-HydroR (PEG). The first two prostheses compared by this method with glutaraldehyde preserved bioprosthesis implanted in the mitral and aortic valves, respectively, in juvenile sheep.

The prostheses treated conventionally with glutaraldehyde showed macroscopic and microscopic calcification, and deposition of thrombotic material. Those already preserved in L-HydroR had spontaneous repopulation by host cells, conferring greater resistance to calcification and thrombogenicity. Rey et al. in 2011 [24] compare morphologically and functionally preserved pulmonary homograft L-HydroR method, with the fresh homograft implanted in juvenile sheep, and evaluated after a period of 320 days. The authors concluded that the homograft treated

by L-HydroR method showed histological evidence of interstitial and endothelial cell repopulation. Recently, Furlanetto et al. in 2009 (25) demonstrated that porcine pulmonary xenograft with L-HydroR preservation placed in the pulmonary position of sheep newborns and followed into adulthood presents growth of the graft, absence of calcification and preservation of pulmonary valve function.

In this context, this study advances in the evaluation of the process of spontaneous endothelialization of valve replacement, this time testing the performance of the model for preservation polyethylene (L-HydroR) in valved tubular prosthesis implanted in the pulmonary artery of sheep.

pericardium, treatment with L-HydroR is fixed inside the tube. Once assembled, the pipe is tested for the competence of the valve and not checked for leaks. Approved, the prosthesis is sterilized in a solution of hydrogen peroxide and ethanol and then packed in a solution of 50% ethanol.

Sterility testing is done using samples incubated in culture media FTM, Middlebrook and STB for 14 days. As soon the is proven sterility, the prosthesis is released. The preservation technique in L-Hydro R consists of three distinct steps: STEP 1: Extraction of the antigens and chemical oxidation of the remaining antigens with polyethylene glycol; STEP 2: Sterilization in hydrogen peroxide; STEP 3: Inventory of the prostheses in ethanol solution at 50%.

The animals were left fasting 24 hours before surgery.

Anesthetic induction was done with Thiopental (IV). The animal was intubated, placed on mechanical ventilation, nasogastric tube passed, electrocardiographic monitoring and shaving the left chest. From a left thoracotomy at the fourth intercostal space, the left lung was removed, made the opening of the pericardial sac and dissection of the pulmonary trunk. Heparinization was performed after cannulation of the ascending aorta and right atrium with the establishment of cardiopulmonary bypass with total hemodilution, normothermia and without aortic clamping.

After complete division of the pulmonary trunk, the native pulmonary valve leaflets were removed. A segment of the graft of approximately 4 cm, containing the cusp was anastomosed to the proximal portion of the outflow of the right ventricle and the pulmonary trunk portion related to the bifurcation, with a continuous suture using 5-0 polypropylene thread. After hemostasis, CPB was discontinued. After replacement of the entire blood volume of the cannulas were removed and administered protamine chloride. A chest drain was placed, the pericardium and the thoracic incision closed approx. The drain was removed when the animal begins to breathe spontaneously. The animal was left under observation for a period of 07 days, after which it was refered to the vivarium after surgery. The animal continued to be observed and evaluated daily during the predetermined period of 150 days, or while he survived.

Evaluation of hematological and biochemical blood was held on the 7th and 90th postoperative day, and the day of sacrifice.

After sacrifice with an injection of potassium chloride, the prostheses were explanted and subjected to macroscopic evaluation. After fixation in 10% formaldehyde, the histological study was conducted to evaluate the deposition of calcium and thrombotic material on the surface of the prosthesis. Bioprostheses were cut, dehydrated in alcohol, embedded in paraffin and sectioned in four micromeres fragments and then were treated with hematoxylin-eosin for evaluation of calcium deposits. The

Objective Evaluate the processes of structural degeneration in vivo pulmonary valve heterografts preserved in L-HydroR and implanted in sheep, with a minimum observation period of five months.

METHODS The study was approved by the Ethics Committee of UNIFESP. Fourteen (14) animals received implantation of the bioprosthesis to be tested (L-HydroR) L- HydroR group (test). Three (03) animals received implants of glutaraldehyde preserved bioprosthesis control Glutaraldehyde group (control). Animals that died before 24 hours after surgery were considered surgical deaths and were excluded from the study. Additional animals were included in the study. Animals that died before the scheduled date of sacrifice were examined and necropsied.

The prosthesis is used in a patch of corrugated bovine pericardium treated by L-HydroR. The closing of the tube is made with two suture lines. A valve made of bovine

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slides were observed under an optical microscope by a pathologist without knowing that the group would be analyzing (assessment “blind”). Both macroscopic and microscopic evaluation, the degree of calcification was quantified (semi quantitative assessment) by considering the anatomopathological examination graduation: 0 - absent calcification, 1 - mild calcification, 2 - moderate calcification, 3 – Important calcification .

The autopsies were performed in all cases. Samples were collected using swabs for bacteriology. The samples were subjected to radiological examination to determine the distribution and intensity of calcium deposits in the valve leaflets, as well as the tube, and used a Senographe DMR mammography unit (GE, Buc. France). The degree of calcification was rated from zero to three (0-3). Fragments of the tube and the leaflets were dehydrated in an oven at 50°C and mineralized in muffle furnace at 800oC, dissolved in nitric acid (HNO3 - 2.5 M) determined the amount of calcium (expressed as ug / mg dry tissue) by method of atomic absorption spectrophotometry, using the Perkin Elmer spectrophotometer of 1.000 mg/L with addition of 1% lanthanum chloride (Baucia et al., 2006).

All categorical data are expressed as proportions, whereas quantitative variables are expressed as mean ±

standard deviation. Histograms were made to assess the normal distribution of quantitative data. We chose to use Fisher’s exact test to compare the observed frequencies in L-HydroR Group (test group) with the frequencies observed in the glutaraldehyde group (control group). To compare quantitative data between groups (cases versus controls), the Student t test or Mann-Whitney test were used when appropriate. The significance level was preset at 5%. The software used was SPSSR. RESULTS Nineteen animals underwent the procedure for replacing the pulmonary valved tubular graft. The operative mortality rate was 10.53% (two animals). The cause of death was hypovolemic shock secondary to intra-operative bleeding.

The seventeen remaining animals were included in the study. Chart 1 summarizes the information related to the study.

In Group L-HydroR Group, two animals died before sacrifice. The first, on the 86th postoperative day, the cause of death was endocarditis, confirmed by autopsy. The second animal was found dead on the 165th postoperative day, while waiting for the sacrifice. Autopsy showed no

Chart 1. Surgical data

L-Hydro® group 1 2 3 4 5 6 7 8 9 10 11 12 16 17

Gender

Weight (kg)

Age (months)

CPB (min)

Survival (days)

Size Prosthesis

Status

F M F M M M M M M M M M F M Gender

34 30 35 30 27 30 35 35 33 33 32 32 30 28 Weight (kg)

8.13 7.93 6.77 6.13 6.20 7.37 6.73 6.73 6.60 6.67 6.77 6.77 7.67 8.33 Age (months)

76 93 79 76 62 100 49 71 48 28 34 30 39 35 CPB (min)

165 197 194 151 168 174 162 162 86 161 161 162 154 154 Survival (days)

17 17 17 17 15 17 17 17 17 17 17 17 19 19 Size Prosthesis

Death Sacrificed Sacrificed Sacrificed Sacrificed Sacrificed Sacrificed Sacrificed Death Sacrificed Sacrificed Sacrificed Sacrificed Sacrificed Status

38 30 25

161 161 161

17 17 17

Sacrificed Sacrificed Sacrificed

Glutaraldehyde group 13 M 35 6.30 14 M 33 6.30 15 M 33 6.50 M = male, F = female. CPB – Cardiopulmonary bypass

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evidence of endocarditis. There were, however, signs of respiratory infection in the right lung (congestion and edema).

The detection of calcifications, mammographic technique, the prosthesis preserved in L-HydroR, was limited to the sewing area of the prosthesis (Figure 1). As the prosthesis was already preserved in glutaraldehyde, the calcification occurred in all prostheses and spread to the wall of the tube and the valve leaflets (Figure 2). The case 13 showed calcification moderate (grade 2) and cases 14 and 15, significant calcification (grade 3) (Table 1).

Table 1. Measurement of calcification: 0 - no calcification, 1 mild calcification; 2 - moderate calcification, 3 significant calcification.

L-Hydro® group Calcification of leaflet Calcification of tube mammography mammography 1 0 0 2 0 0 3 0 0 4 0 0 5 0 0 6 0 0 7 0 0 8 0 0 9 0 0 10 0 0 11 0 0 12 0 0 16 0 0 17 0 0 Glutaraldehyde Calcification of leaflet Calcification of tube group mammography mammography 13 2 2 14 3 3 15 3 3

Fig. 1 - Appearance radiological graft preserved in L-Hydro ® (no calcification)

Statistical analysis revealed significant difference (P = 0.001) compared between groups and L-HydroR Glutaraldehyde, as shown in Table 2.

Macroscopic evaluation of all prostheses in Glutaraldehyde Group showed gross calcification of the leaflets and the tube. In two of these prostheses calcification was classified as severe. But among the prostheses in L-Hydro R Group two (14.3%) showed calcification quantified as mild, tube. Only in one leaflet of a prosthesis was verified the presence of calcification, quantified as mild (Table 3).

Another finding was observed in the macroscopic partial or total adherence of the leaflets to the wall of the tube (Figure 3). This occurred in seven (50%) animals, all in LHydroR Group. In three animals (21.4%), all the prosthetic leaflets were attached to the tube wall. Two animals (14.3%) had adhered hum of brochures and other two animals (14.3%), two leaflets were attached to the tube wall. There

Fig. 2 - Radiological Appearance of prosthesis preserved in glutaraldehyde (diffuse calcification)

Table 2. Statiscal analysis of mammography (L-Hydro® and Glutaraldehyde groups).

Variable* L-Hydro® Glutaraldehyde group group (n=14) (n=3) Calcification (moderate / significant) of leaflets (mammography) __ 3 (100%) Calcification (moderate / significant) of the tube (mammography) __ 3 (100%)

P Value†

0.001 0.001

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Table 3. Measurement of calcification: 0 - no calcification, 1 - mild calcification; 2 - moderate calcification, 3 significant calcification. Assessment of adherence of leaflets.

L-Hydro® group Calcification of leaflet Adherence of leaflet (s)-(N) Calcification of tube 1 3 0 0 2 0 0 1 3 0 0 0 4 0 2 0 5 1 0 0 6 0 0 1 7 0 1 0 8 1 0 0 9 0 0 3 10 0 0 0 11 3 0 0 12 0 2 0 16 0 0 0 17 0 0 0 Glutaraldehyde group Calcification of leaflet Adherence of leaflet (s)-(N) Calcification of tube 13 2 0 2 14 0 3 3 15 3 0 3 (N = Number of leaflets adhered)

Fig. 3 - Macroscopic post-explant. Total adherence of the leaflets to the tube wall (Group L-Hydro ®)

were no signs of adherence to the tube wall leaflets in the Glutaraldehyde Group.

Calcification in the variables of tubes and calcification of leaflets significant (P = 0.001) in the comparison between L-HydroR and Glutaraldehyde Groups. In the variable adherence of leaflets, this statistical difference was not observed (P = 0.228), as shown in Table 4.

Microscopic evaluation was performed in 16 animals, 13 in L-HydroR Group and three in Glutaraldehyde Group (Table 5). The staining by hematoxylin-eosin showed signs of calcification in the cusps of seven of the 13 animals in LHydroR Group(53.8%), and the tube of ten of the 13 animals of the same group (77%). This was calcification, but it was classified as mild in all cases. No animal in L-HydroR Group had moderate or severe calcification of cuspids or tube (Figure 4).

Microscopic examination of the animals in Glutaraldehyde Group showed significant calcification of all cusps and fragments of pipe measured. The microscopy

Table 4. Statistical analysis of macroscopy (L-Hydro® and Glutaraldehyde groups).

Variable* L-Hydro® Glutaraldehyde group group (n=14) (n=3) Calcification (moderate / significant) of the cusps (macroscopy) __ 3 (100%) Calcification (moderate / significant) of the tube (macroscopy) __ 3 (100%) Adherence of leaflets (microscopy) 7 (50%) __

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P Value†

0.001 0.001 0.228

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also showed macrophage inflammatory fibrinoid deposits and absence of thrombi or clots in the samples analyzed in both groups (Figure 5).

The statistical analysis shows significant difference (P = 0.001) in the variables calcification of cusps and tube in the comparison between L-HydroR and Glutaraldehyde

Groups (Table 6).

The dosage of calcium by atomic absorption spectrophotometry showed a higher concentration of calcium in the implants preserved in glutaraldehyde, compared to those preserved in L-HydroR (P= 0.017). Table 7 shows the values obtained from this technique.

Table 5. Measurement of calcification: 0 - no calcification, 1 mild calcification, 2 - moderate calcification, 3 significant calcification.

L-Hydro® group Calcification of Calcification of leaflet tube 1 NE NE 2 1 1 3 1 1 4 0 0 5 1 1 6 0 1 7 0 1 8 0 0 9 1 1 10 0 1 11 1 1 12 1 1 16 1 1 17 0 0 Glutaraldehyde Calcification of Calcification of group leaflets tube 13 3 3 14 3 3 15 3 3

Fig. 4 - Microscopic view of the prosthesis preserved in L-Hydro ®. Staining with hematoxylin-eosin. In lilac, isolated spots of calcification

NE = Not evaluated Table 6. Statistical analysis of microscopy (L-Hydro® and Glutaraldehyde groups).

Variable*

L-Hydro®

Glutaraldehyde

P

group

group

Value†

(n=14)

(n=3)

__

3 (100%)

0.001

__

3 (100%)

0.001

Calcification (moderate / significant) of the cusps (microscopy) Calcification (moderate / significant) of Fig. 5 - Microscopic (optical microscopy) prosthesis preserved in glutaraldehyde. Staining with hematoxylin-eosin. In lilac, diffuse regions of calcification and severe

the tube (microscopy)

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Table 7. Dosing Calcium (mg/mg) by atomic absorption spectrophotometry.

Atomic Absorption L-Hydro group速 43.84 1 139.44 2 48.7 3 14.2 4 25.7 5 240.9 6 206.6 7 98.3 8 58.39 9 53.76 10 38.97 11 22.4 12 64.04 16 50.01 17 Atomic Absorption Glutaraldehyde group 318.3 13 193.32 14 720.3 15

case of prostheses preserved in L-HydroR, Nina et al. [22], observed by scanning electron microscopy, the formation of a new endothelium-resistant exudation of plasma proteins and salts, which are precursors of bioprosthetic degeneration. In their his remarks, Nina et al. [22] concluded that the absence of toxicity, characteristic of L-HydroR preservation, allowed the matrix of the prosthesis from the test group became biocompatible, allowing for spontaneous re-endothelialization, enhancing the resistance to calcification and thrombogenicity.

By scanning electron microscopy and transmission electron microscopy, Rey et al. [24] showed histological evidence of interstitial and endothelial repopulation on the surface of homografts preserved in L-HydroR implanted in sheep. PEG is attributed to the immunosuppressive property, which is based on L-HydroR preservation. As shown by Collins et al. in 1991 [11], antigens that are combined with PEG, have reduced antigenicity. Wicomb et al. in 1992 [15] demonstrated the reduced toxicity of PEG when added to the solution of this substance myocardial preservation, ensuring viability of the organ for a longer time when compared to conventional cardioplegic solutions.

It was observed the occurrence of adhesion of part or all of the prosthetic leaflets in L-HydroR Group (seven animals), compared to Group Glutaraldehyde, where this event has not been verified. One possible explanation for this is the fact that bioprostheses preserved in L-HydroR have, since its preparation, a feature thinner and more flexible compared to prostheses preserved in glutaraldehyde. As the outflow of the right ventricle a low pressure zone, the cusps more flexible would be susceptible to adhere to the tube wall. Changing the design of the prosthesis with the construction of breasts immediately above the valve could perhaps reduce the incidence of adhesions.

Accordingly, further studies testing this new type of prosthesis would allow evaluation of their performance.

Rey et al. [24] in their experimental study with homografts preserved in L-HydroR found from the optical microscopy, slightly retracted cusps with progressive thinning toward the free edge. The atomic absorption spectroscopy, as well as macro and microscopic evaluations, showed higher concentrations of calcium in the prosthetic Glutaraldehyde Group. There were significant, which proves the feasibility evaluation of calcium by this method [27].

This study presents a limitation to the inability to reproduce the effect of heart disease and coagulation profile comparable to that of man, like others who have used large animals in the evaluation of new technologies for preservation or replacement of cardiac tissues [5,17].

Moreover, animal models, although similar to the human anatomy, have different antigenicity, which may lead to non-reproducible results when the clinical use [12]. In the present study, replacing the pulmonary valve with atubular

DISCUSSION The implantation of biological valve prostheses that allow and promote spontaneous coating with host cells was proposed by Frater et al. [21] and is the principle behind the development of L-HydroR preservation used in this study. In the present study, we used as a preserving agent L-HydroR tube valved bovine pericardium implanted in the outflow of the right ventricle of sheep. These animals have been used by several authors and have the characteristic of being docile and allow easy handling during the test period. In the case of large animal and fast growth and development, pathophysiological changes resemble those that occur in man during life. The time of at least 150 days was necessary for the sheep present height and weight development compatible with the proper adulthood [26] can be verified or not the occurrence of calcification, as well as analyze, this type of bioprosthesis, the hemodynamic performance of the same, as far as wear.

Like the studies of Nina et al. in 2003 [22], Santos et al. in 2007 [23] and Rey et al. in 2011 [24], the radiological assessment, the present study demonstrate a significant difference in the verification of calcification of the prosthesis had preservation with L-HydroR, versus those that were preserved in glutaraldehyde. The latter with a greater degree of calcification. Likewise, the example of these studies, macroscopic and microscopic evaluation showed a greater degree of calcification in bioprostheses preserved in glutaraldehyde. In relation to microscopy, the results show higher calcification of glutaraldehyde preserved grafts, as well as studies Nina et al. [22] and Santos et al. [23]. In the 426

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graft preservation in L-HydroR was suitable for evaluation as an experimental model as it allows analogy to what may occur with the human species. Preservation with L-HydroR indicated significant reduction in the calcification of the tube and in the leaflets of the bioprosthesis used. New performance measures should be taken from this study, aiming at the observation and clinical applicability. The proof of the existence and viability of interstitial tissue and repopulation can be achieved through further studies.

cardioplegia on cold, preserved rabbit heart. Ann Thorac Surg.

1997;63(2):459-64.

CONCLUSION The prostheses preserved in L-HydroR (not aldehydic) were more resistant to the process of tissue degeneration, calcification especially when compared to those preserved in glutaraldehyde.

10. Carpentier A, Deloche A, Relland J, Fabiani JN, Forman J, Camilleri JP, et al. Six-year follow-up of glutaraldehydepreserved heterografts. With particular reference to the treatment of congenital valve malformations. J Thorac Cardiovasc Surg. 1974;68(5):771-82.

11. Collins GM, Wicomb WN, Levin BS, Verma S, Avery J, Hill JD. Heart preservation solution containing polyethyleneglycol: an immunosuppressive effect? Lancet.

1991;338(8771):890-1.

12. Lopes SAV, Costa FDA, Paula JB, Dhomen P, Phol F, Vilani R, et al. Análise do comportamento biológico de heteroenxertos descelularizados e homoenxertos criopreservados: estudo em ovinos. Rev Bras Cir Cardiovasc. 2009;24(1):15-22.

13. Schoen FJ, Levy RJ. Calcification of tissue heart valve substitutes: progress toward understanding and prevention.

Ann Thorac Surg. 2005;79(3):1072-80.

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ORIGINAL ARTICLE

Rev Bras Cir Cardiovasc 2012;27(3):429-35

Assesment of CABDEAL score as predictor of neurological dysfunction after on-pump coronary artery bypass grafting surgery Avaliação do escore CABDEAL como preditor de disfunção neurológica no pós-operatório de revascularização miocárdica com circulação extracorpórea

Vinícius José da Silva Nina1, Maria Iracema de Amorim Rocha2, Rayssa Fiterman Rodrigues2, Vanessa Carvalho de Oliveira3, João Lívio Linhares Teixeira3, Eduardo Durans Figueredo4, Rachel Vilela de Abreu Haickel Nina5, Carlos Antonio Coimbra Sousa2

DOI: 10.5935/1678-9741.20120072

RBCCV 44205-1403

Abstract Introduction: Neurological dysfunction is a feared postoperative morbidity of cardiac surgery, an important cause of death and increased spending in hospitals. Its prediction, however, is still uncertain.

Objective: To assess the applicability of a preoperative score as a predictor of neurological dysfunction after coronary artery bypass grafting (CABG) under cardiopulmonary bypass (CPB).

Methods: Prospective study that evaluated 77 patients who underwent CABG from February to October 2011. Using the score CABDEAL (creatinine, age, body mass index, diabetes, emergency surgery, abnormality on ECG, lung disease), patients were grouped into high (CABDEAL > 4)

and low risk (CABDEAL<4). The predictive value of the score was compared with intraoperative and postoperative variables (aortic clamping time, CPB and ventilation time) as predictors of encephalopathy and stroke. Data were analyzed with descriptive statistics and compared with the Fisher exact test. ROC curve analysis was performed to evaluate the accuracy of the model for the neurological outcomes. It was considered the significant value P<0.05.

Results: The mortality rate was 2.6% (n=2). There were 2 episodes of stroke (2.6%) and 12 (15.5%) of encephalopathy.

High risk CABDEAL (P=0.0009), ventilation time (P=0.014), CPB time (P=0.02) and aortic clamping time (P=0.006) were significantly associated with encephalopathy. The aortic clamping time was also associated with stroke (P=0.03) and

1. Doctor of Science. Adjunct Professor. Chief of Cardiac Surgery, University Hospital, Federal University of Maranhão.

2. Internal Student of Medical School at the Federal University of Maranhão.

3. Internal Student of Medical School at the Federal University of Maranhão.

4. Student of Medical School at the Federal University of Maranhão.

5. Student of Medical School at the Federal University of Maranhão.

6. Doctor. PhD in Public Health, Federal University of Maranhão.

7. Pediatric Cardiologist. Doctorate Student in Public Health, Federal University of Maranhão.

8. Internal Student of Medical School at the Federal University of Maranhão.

Work performed at the Department of Cardiac Surgery, University Hospital, Federal University of Maranhão.

Presented at the 39th Congress of the Brazilian Society of Cardiovascular Surgery, Maceió, AL, from April 12th to 14th, 2012 Correspondence address: Vinícius José da Silva Nina Rua Barão de Itapary, 227 – 4º andar – Centro – São Luís, MA Brazil – Zip code: 65020-070 E-mail: rvnina@terra.com.br Article received on May 9th, 2012 Article accepted on July 6th, 2012

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Abbreviations, acronyms & symbols AHA CPB CABG CVA ROC SUS

American Heart Association Cardiopulmonary bypass Coronary artery bypass grafting Cerebrovascular accident Receiver Operating Characteristics Unified Health System

death (P=0.006). CABDEAL score showed the largest area under the ROC curve rather than others variables.

Conclusion: In this study, the CABDEAL score stood out as the best predictor of encephalopathy after CABG when compared to the others intraoperative variables.

Keywords: Myocardial revascularization. Risk assessment. Morbidity. Brain damage.

Resumo Introdução: As complicações neurológicas são temidas no pós-operatório das cirurgias cardíacas, sendo importante causa de óbito e de gastos hospitalares. Sua predição ainda é incerta.

Objetivo: Avaliar a aplicabilidade de um escore préoperatório como preditor de disfunção neurológica no pósoperatório de revascularização miocárdica (RM) com circulação extracorpórea (CEC).

INTRODUCTION Surgery for coronary artery bypass (CABG) is the major surgical procedure most commonly performed worldwide [1]. According to the American Heart Association (AHA), only in the United States, from 1996 to 2006, the number of cardiac surgeries reached the mark of 7,235,000 procedures.

Only in 2006, 448,000 CABG surgeries were performed [2].

However, in spite of its broad execution and development over the years, it still implies certain risks for the patient.

Among the complications, cerebrovascular accident (CVA) and other ischemic neurologic events are the most feared after CABG. The risk of stroke in patients undergoing CABG is estimated at 2%. This rate increases significantly according the age increase of the patient, in elderly patients reaching the value of 9% [3].

Another dysfunction expected, although less studied is the encephalopathy, presented as delirium, confusion, coma and convulsions in the immediate postoperative 430

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Métodos: Estudo prospectivo que avaliou 77 pacientes submetidos à RM no período de fevereiro a outubro de 2011.

Utilizando-se o escore CABDEAL (creatinine, age, body mass index, diabetes, emergency surgery, abnormality on ECG, lung disease), os pacientes foram agrupados em alto (CABDEAL > 4) e baixo risco (CABDEAL<4). Para os desfechos encefalopatia e acidente vascular encefálico (AVE), foram comparados os valores preditivos do escore e das variáveis intra e pós-operatórias (tempos de pinçamento aórtico, CEC e ventilação mecânica). O teste exato de Fischer foi usado na análise estatística. A análise da curva ROC foi utilizada para avaliar a acurácia do modelo para os desfechos neurológicos. Adotou-se o nível de significância P<0,05.

Resultados: A taxa de mortalidade foi de 2,6% (n=2).

Ocorreram dois episódios de AVE (2,6%) e 12 (15,5%) de encefalopatia. O desfecho encefalopatia associou-se significativamente com CABDEAL de alto risco (P=0,0009), tempo de ventilação mecânica (P=0,014), tempo de CEC (P=0,02), e tempo de pinçamento aórtico (P=0,006); este último associou-se também com AVE (P=0,03) e óbito (P=0,006). O escore CABDEAL apresentou maior área sob a curva ROC do que as demais variáveis para o desfecho encefalopatia.

Conclusão: Na amostra estudada, o escore CABDEAL foi melhor preditor de encefalopatia no pós-operatório de RM quando comparado às variáveis intraoperatórias analisadas.

Descritores: Revascularização miocárdica. Medição de risco. Morbidade. Dano cerebral.

period. This morbidity is associated with the increase in hospital stay and mortality [4]. It is a common complication in cardiac intensive care units and its incidence varies from approximately 8.4% to 32% [5,6].

The problem involving the brain damage in cardiac surgery is multifactorial, including risk factors in the pre-, intra-and postoperative period, such as age, gender, previous neurological disease, carotid artery disease, microembolisms, perfusion disorders, metabolic disorders, inflammatory responses [7]. The prevalence of these complications is very variable and depends mainly on the pacing in postoperative neurological outcome [8].

Predictive models can be used to estimate the chances of these complications and others, allowing to choose the best treatment for the patient and the consequent reduction in morbidity and mortality [9]. However, the majority models evaluates the mortality as the main outcome, there are few that contemplate postoperative morbidities such as stroke, mediastinitis and atrial fibrillation [10-13].

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Among the existing, the CABDEAL (Creatinine, Age, Body Mass Index, Diabetes, Emergency Surgery, Abnormal ECG, Lung Disease), a score proposed by Kurki et al. study [14], proved to be easily applied and a good predictor of morbidity [15,16].

Studies involving neurological events in the postoperative period of CABG surgery allow us to realize the importance of predicting these complications, both for patient management and to decrease hospital costs involved in treatment. Thus, this study aimed to identify risk factors predictive for the occurrence of stroke and encephalopathy in the postoperative period of CABG surgery with cardiopulmonary bypass and evaluate the applicability of CABDEAL score, as a predictor of these morbidities when compared to intra-and postoperative variables.

stay, presence of atrial fibrillation, stroke in the trans and postoperative period and presence of delirium, convulsions and coma or death.

METHODS Type of study This is an analytical, longitudinal, descriptive and prospective study, conducted at the Department of Cardiac Surgery, University Hospital, Federal University of Maranhão, President Dutra Unit (HU-UFMA) in São Luís MA. Sample The convenience sample is consisted of all patients undergoing on-pump CABG during the period from February to October 2011.

Inclusion criteria The study included all patients undergoing isolated on-pump CABG during the study period.

Exclusion criteria Patients who underwent to another concomitant cardiac surgery as: valve replacement, correction of congenital defect, aortic surgery, carotid endarterectomy and reoperations were not included in this study.

Data Collection Data Colletion, by filling out an application form, was obtained after the patients have signed the consent form.

In the preoperative period, the data collected were: age, body mass index, value of preoperative creatinine, presence of abnormal preoperative electrocardiogram, hypertension, diabetes, emergency surgery, prior stroke and presence of chronic obstructive pulmonary disease.

In the postoperative period, the following information were collected: duration of surgery, cardiopulmonary bypass time, aortic clamping time, duration of mechanical ventilation, length of hospital

Definitions of variables Delirium, coma and convulsion were considered as evidence of the presence of encephalopathy in the immediate postoperative period [4].

The criteria for delirium was the same adopted in the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV), which includes the following: episodes of confusion, agitation, changes and fluctuations in the level of consciousness, acute problems of cognition, including memory and changes perceptions including hallucinations.

The presence of these signs was documented by medical and nurses’staff from the hospital and it was collected through observation and records in the patient.

The presence of chronic obstructive pulmonary disease was observed in the preoperative period, through the execution of a spirometry, whose criteria was the same recommended by the protocol used by the author of the CABDEAL score: a value of forced expiratory volume of 1 second equal or less than 50% determined the presence of obstructive disease [10].

Prolonged hospital stay in this study was determined by length of stay exceeding six days, based on the historic series of the last year, whose median was 6 days.

To define prolonged ventilation time, it was considered as cutoff the median of 680 minutes, 160 minutes being the minimum and the maximum of 28,800 minutes.

Application of the score The application of CABDEAL score consisted of analysis of the following variables: creatinine, age, body mass index, diabetes, emergency surgery, abnormal electrocardiogram, and obstructive pulmonary disease (Table 1).

The value of CABDEAL score ranges from 0 to 10, with the level 2 considered as the cutoff point. If the patient has a score of 0 or 1, the probability of post-operative morbidity is low (<15%). If the score is 2, this probability raises to 26%. Score 3 provides of 46%. A score of 4 or superior, the probability is higher than 75%. However, if the score reaches the value 8, the chance of morbidity is 100% [10].

For purposes of analysis and application of CABDEAL score, it was established a variable in the risk category, with a cutoff equal to 4 for best prediction of outcomes.

CABDEAL score patients below to 4 were considered low risk, while those whose scores were higher or equal to 4 were considered high risk patients. The same procedure was repeated for clamping time and CPB time, generating as cutoff values for prolonged periods of 89 minutes and 105 minutes respectively.

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Risk category in CABDEAL score, CPB time > 105 minutes, clamping time > 89 minutes, length of stay > 6 days and mechanical ventilation time exceeding 680 minutes were evaluated as risk factors for hospital death and neurologic dysfunction.

Ethical aspects The research project was submitted to the University Hospital Presidente Dutra Ethics Committee, in accordance to Resolution 196/96 CNS-MS for research involving human subjects, and it was only implemented after approval under the consolidated stand number 248/10. All subjects involved in the study signed a consent form.

Statistical analysis Quantitative variables were presented as mean, median, standard deviation, percentages, odds ratios and confidence intervals. The Shapiro-Wilk test was used for testing the normality of the sample. The Chi-Square test was used in the qualitative variables, and when necessary was used the Fisher’s exact test for correction. ROC curves were used to identify the best cutoff points of some continuous variables and, therefore, predict adverse postoperative events, determining the accuracy of the model.

The statistical significance was indicated by a value of P <0.05.

The data were processed in the computer statistical programs STATA 11.0 (Stata Corporation, College Station, TX) and EPI INFO.

Table 1. CABDEAL Score Variable Creatinin (µmol/L)* Age Body Mass Index Diabetis Emergency Surgery Abnormalityon ECG Lung Disease

Negative Positive Weight <110 >111 2 <69 >70 1 <27 >28 1 No Yes 2 No Yes 2 No Yes 1 No Yes 1

Kurki et al .Ann ThoracSurg 1996;61:1740-1745, *110 µmol/L =1,2mg/dl, ** ECG=Eletrocardiogram(non-sinus rhythm, ST Ischemia signs) Note: Maximum score points: 10 points Cutoff point: 2 (0-1: low probability of morbidity / > 2: High) Risk of Morbidity: 0-1: 15% 2: 26% 3: 46% >4: >75% 8: 100%

RESULTS The sample consisted of 77 study patients, 17 (22.1%) women and 60 (77,9%) men whose ages ranged from 36 to 81 years with a mean of 61.3 ± 9.2 years. Seventy patients (90.91%) were hypertensive, and 8 (10.39%) reported previous stroke.

The value of CABDEAL score ranged from 0 to 7, and 47 (61%) patients were classified as low risk (score <4) and 30 (39%) in high risk (score > 4).

The mortality rate in the sample studied was 2.6% (two cases). Encephalopathy and stroke were present in 15.58% and 2.6% respectively.

By analyzing the association between the level of CABDEAL risk with the outcomes death and neurological morbidities, just encephalopathy was significantly associated with the preoperative score high risk (P = 0.0009).

The CABDEAL of high risk was also associated with prolonged length of hospital stay (P <0.0001).

By associating the time of CPB and aortic clamping with the outcome of encephalopathy, stroke and death, it was observed that CPB time > 105 minutes was only associated with the occurrence of encephalopathy (P = 0.02), whereas the clamping time > 89 minutes was significantly associated with all those three outcomes. The median ventilation time > 680 minutes, in turn, was only significantly associated with the outcome of encephalopathy (Table 2).

The ROC curve analysis to evaluate the performance of variables predictive of postoperative encephalopathy showed that CABDEAL score presented the biggest area under the curve (area = 0.811 ± 0.053), being the best predictor of outcome in relation to other variables tested, whose sensitivity and specificity was 83% and 69.2%, respectively (Table 3/Figure 1).

Table 2. Association between predicting variables and the outcomes of encephalopathy, stroke1 and death in the postoperative of On-pump CABG Encephalopathy P-value Stroke P-value Death P-value n (%) n (%) n (%) High-riskCABDEAL 10 (13%) 0.0009 1 (1.3%) 0.630 2 (2.6%) 0.148 Prolonged CPB time 7 (9.1%) 0.02 1 (1.3%) 0.492 2 (2.6%) 0.07 Prolonged aortic clamping time 6 (7.8%) 0.006 2 (2.6%) 0.03 2 (2.6%) 0.03 Extended Ventilation time 10 (13%) 0.014 2 (2.6%) 0.253 2 (2.6%) 0.253

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Table 3. ROC curve analysis of the variables pre-and intraoperative predictors of encephalopathy in the postoperative of On-pump CABG Index Area under the Standard P-Value Asymptotic confidence interval curve Error of 95% LowerLimit UpperLimit Score 0.811 0.053 0.001 0.705 0.914 CPB 0.706 0.085 0.024 0.539 0.872 Aortic clamping 0.657 0.088 0.084 0.485 0.831

Fig.1 - Sensitivity and specificity of predicting variables of encephalopathy in the postoperative period of on-pump CABG

DISCUSSION Estimates indicate that in 2020, cardiovascular diseases will contribute with 25 million deaths annually, and ischemic heart diseases appear as the first cause of mortality worldwide. In Brazil, they already represent 30% of admissions in SUS (Unified Health System) and are among the main causes of mortality [17].

Previous studies have shown that the majority of patients referred for coronary artery bypass reach increasingly elderly and with other comorbidities [18].

Following this trend, in our center, the majority of patients undergoing CABG surgery had a mean age of 61.3 years and their disease was often associated with comorbidities such as hypertension, obesity, diabetes, renal disease, lung and obesity [8,19].

Among the most feared adverse events in coronary artery bypass grafting are the stroke, and less discussed in literature, but not less important, the occurrence of encephalopathy [20]. Predicting these events, allows optimizing the clinical and surgical management of the patient, not only reducing the negative impact on their quality of life, but also the heavy financial burden in the hospital costs [21].

The most cited models of predicting still leave gaps since they stick specifically to the risk of death [18,19,22]

or when directed to neurological events, seek to provide only the risk of stroke [21,22].

In this study, we sought to test a score that could be a predictor, not only of stroke but also encephalopathy. The chosen CABDEAL score, although not specific to both complications, presents in its scope, the most prevalent risk factors for the determination of these events and, unlike other scores, can extend its prediction also to the risk of common diseases for this surgery such as central nervous system dysfunction, postoperative infection, arrhythmia, renal failure and death, in addition, it allows estimating the chance of the patient likely to have prolonged hospital stay.

The CABDEAL is a simple, short and mnemonic model in its variables and unlikely other scores, it is convenient to be applied at the bedside of the patient, facilitating the clinical routine [14,16]. Based on these principles, the authors of this study applied the score and compared the total value with the chance of development the following outcomes: postoperative stroke, encephalopathy, prolonged length of hospital stay and death. Subsequently with the objective of verifying its predictive power, it was compared with other known risk factors for this surgery, which are not included in its variables, but are cited as predisposing these complications, which are: cardiopulmonary bypass time, length of aortic clamping and the duration of mechanical ventilation [23,24].

In spite of the influence of CPB as a triggering factor independent of brain damage has already been well established, there is no consensus about the effect of aortic clamping time as the cause of these events. The 2.6% occurrence of stroke in this study did not present significant correlation with the high value of the score. However, it was associated to prolonged periods of CPB and aortic clamping [24]. There are few studies on the technique of clamping influencing the occurrence of neurological events.

It is postulated that the continuous clamping bring greater risk of stroke and other neuropsychological disorders for the patient [25]. Kim et al. concluded that there is no difference in the incidence of postoperative stroke or hospital mortality in patients who had only a clamping compared with two clamping [26]. While, Antunes et al.

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postulated that aortic clamping itself is single or intermittent, and it is also a risk factor for the occurrence of stroke, increasing the risk by 1.3 times for each additional period of aortic clamping [27]. Guaragna et al. [28] claim that these events are caused not only by the clamping time, but by the presence and location of plaques in the aorta that can lead to the formation of microbubbles that result from the manipulation of the aorta at the time of the application and removal of aortic clamps as shown by Barbut et al. [29].

In this study, the only postoperative variable which showed anassociation with the encephalopathy was prolonged mechanical ventilation. However, in the literature it is still not well established what the prolonged ventilation time would be, which may vary from 480 minutes up to 7-14 days [30]. It is accepted that postoperative extubation, which exceeds 8 hours, is significantly associated with neurological and / or lung complications. Thus, for analysis purposes, we adopted the cutoff point of 680 minutes, since that would be, therefore, within that interval related to the onset of complications [31].

Kurki et al. to propose the CABDEAL, evaluated 21 risk factors and extracted 7 as the most frequent (creatinine level, age, body mass index, diabetes, emergency surgery, ECG abnormalities and pulmonary disease) [15]. However, by analyzing scores of specific predictors of neurological morbidities, such as the one developed by the Northern New England Cardiovascular Disease Study Group and the Stroke Risk Index [11,12], it is observed that these variables are also part of these two models, which could explain the association of high risk CABDEAL with the occurrence of encephalopathy as noted in previous studies and in the present study.

The sample size and the absence of data in all the cases of the Doppler fluxometric preoperative evaluation of carotid system caused limitations in this study.

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2004;25(5):791-800.

CONCLUSION The score CABDEAL, in this study, proved to be a better predictor of neurological dysfunction in the postoperative period of CABG when compared to analyzed intraoperative variables, such as: cardiopulmonary bypass time and aortic clamping.

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REVIEW ARTICLE

Rev Bras Cir Cardiovasc 2012;27(3):436-45

Gaseous microemboli in cardiac surgery with cardiopulmonary bypass: the use of veno-arterial shunt as a preventive method Microembolia gasosa em operação cardíaca com uso de circulação extracorpórea: emprego de shunt venoarterial como método preventivo

Edison Emidio dos Reis1, Livia Dutra de Menezes2, Caio César Lanaro Justo3

DOI: 10.5935/1678-9741.20120073

RBCCV 44205-1404

Abstract Neurological complications are an important cause of morbidity in the postoperative period of cardiac surgery and its incidence reaches up to 75% of patients. An important cause of these events is the formation of microbubbles in the bloodstream during cardiopulmonary bypass. Integrative review was carried out on gaseous microemboli in cardiopulmonary bypass. This study analyzed studies with different methodological approaches, but that address the issue. The result suggests the denitrogenation of blood by hyperoxia dissolved microbubbles in the blood and venoarterial shunt can balance the respiratory parameters changed with hyperoxia.

Resumo As complicações neurológicas representam importante causa de morbidade no período pós-operatório de cirurgia cardíaca e sua incidência alcança até 75% dos pacientes. Uma importante causa desses eventos é a formação de microbolhas na corrente sanguínea durante a circulação extracorpórea.

Realizou-se revisão integrativa sobre microembolia gasosa na circulação extracorpórea. Esse trabalho analisou estudos com abordagens metodológicas diferentes, mas que contemplam o tema. O resultado sugere que a desnitrogenação do sangue causada pela hiperoxia dissolve microbolhas formadas no sangue e o shunt venoarterial pode equilibrar os parâmetros respiratórios alterados pela hiperoxia.

Descriptors: Extracorporeal circulation. Embolism, air.

Cognition disorders. Cardiac surgical procedures.

Descritores: Circulação extracorpórea. Embolia aérea.

Transtornos cognitivos. Procedimentos cirúrgicos cardíacos.

1. Biologist - UNIMONTES-MG, Brazil. Technical adviser. Author 2. Biomedical - Methodist University, São Paulo, SP, Brazil.

3. Biomedical - Methodist University, Physiologist - ABC University, São Paulo, SP, Brazil

Correspondence address: Edison Emidio dos Reis Rua Desembargador Eliseu Guilherme, 147 – Paraíso – São Paulo, SP, Brazil – Zip Code: 04004-030 E-mail: edisonreis@hotmail.com

Work carried out at Heart Hospital, São Paulo, SP, Brazil.

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Article received on March 5th, 2012 Article accepted on August 23rd, 2012

Reis EE, et al. - Gaseous microemboli in cardiac surgery with cardiopulmonary bypass: the use of veno-arterial shunt as a preventive method

Abbreviations, acronyms & symbols Atm CaO2 CcO2 FEO2 Hb N2 PAO2 PH2O PN2 Pox.O2 PVC Qs/Qt SaO2 SvO2 VO2

atmosphere Oxygen content of arterial blood Capillary Oxygen Content Fraction of expired oxygen hemoglobin Nitrogen Alveolar oxygen tension.

Water vapor pressure Arterial Nitrogen Pressure Oxygen saturation of the hemoglobin of arterial blood Polyvinyl chloride Shunt as percent of total blood flow Oxygen saturation of the hemoglobin of arterial blood mixed venous oxygen saturation oxygen demand

INTRODUCTION Technology has led to a reduction of morbimortality in cardiac surgery [1-2]. However, neurological complications related to it still represent an important cause of morbidity in the postoperative period [3,4]. Cardiopulmonary bypass (CPB) was introduced into cardiac surgery 60 years ago, and since then, it has been reported that certain patients develop some type of neurological repercussion [1,2,5].

From then on, neurological aftereffects and CPB itself have become the focus of much research [6]. It is believed that the incidence of these complications, in differing degrees, affects up to 75% of patients [5-8]. Fortunately, the great majority are sub-clinical. But clinically, significant cases of cerebral air embolization are largely sub-diagnosed, sub-treated, and sub-notified [3,9,10].

Because it is not a technology that maintains principles of normal physiology, its routine use stimulated analysis of the complications associated with it [10], and as a result, it has a large evolution of procedures and materials used in CPB. In spite of all the progress, neurological complications still occur, and are frequently the cause of serious injure [4, 10]. It is known that the post-operative cognitive alterations observed are caused by multiple factors [8], inherent to the patient or inherent to the surgical procedure itself, which, in conjunction may determine a greater or lesser degree of cognitive deficit and morbimortality [10-11].

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Cerebral embolism may be the primary cause of encephalic injure or of the aggravation of pre-existing damage [10]. Gaseous microemboli stand out as the principal cause of neurological disturbances, in addition to inducing inflammatory response by activation of completion, and according to Barak [12] and Rodriguez [13], it can also affect clotting.

Gaseous microemboli can be caused by a number of different sources during cardiopulmonary bypass such as the circuit and oxygenators themselves, in addition to the surgical and perfusion techniques used [14]. Gaseous microemboli can be suddenly displaced from areas where they are and released into the circulation [14]. The process of cooling and reheating the blood modifies the physical properties of the dissolved gases (their solubility) and this predisposes the formation of microbubbles in the bloodstream [10,15]. Perfusionist interventions to administer drugs and collect blood samples produce gaseous microbubbles [2,11,16], as well as vacuum assisted drainage [17,18].

Here we address the application of the veno-arterial shunt, despite having been devised in order to decrease the inflammatory response caused by the passage of blood in the oxygenator, especially in the region of the membrane, it can be an alternative to controlling the production of gaseous microemboli during the operation. Is this system capable of preventing or minimizing these gaseous embolic events? That is what will be discussed below.

METHODS This study raised the hypothesis that hyperoxia can prevent the formation of microbubbles using a veno-arterial shunt in the membrane oxygenators for CPB. Thus, we proposed an integrative review [19] on the subject of gaseous microemboli during CPB. This type of work allows us to analyze studies with different methodological approaches that address the issue. The selected studies in this type of work lead to the building of a body of knowledge necessary for technical-scientific improvement [20]. The bibliographic research was conducted between December 2010 and September 2011 in the following databases: The Journal of Extracorporeal Technology, www.ctsnet.org, http://www.scielo.br/, www.anesthesiology.com, http://www.anesthesia analgesia.org/, and www.perfline.com, http:// circ.ahajournals.org/. Publications from the last 20 years including books of relevance to the study, original, experimental and revision articles were also consulted .The keywords used were: shunt, gaseous microemboli, hyperoxia, microbubbles, neurologic injure after cardiopulmonary by-pass, cerebral air embolism, nitrogen microemboli and cognitive dysfunction after cardiac surgery.

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After the reading the analysis of 169 selected articles and 3 books on specific chapters relating to the content, we selected 48 articles that addressed the topic and were related to our objective. The articles were selected, accessed and printed electronically from the site of the database and through the acquisition of journals.

the higher the gas pressure the greater its diffusion between these means through the membranes [1].

Air is a gas mixture consisting of nitrogen, oxygen and carbonic gas and other gases to a lesser extent, as shown in Table 1. The pressure exerted by each gas component of air is defined as partial pressure [1].The general characteristics of the diffusion of gases allow us to quantify how quickly a gas can diffuse, that is called diffusion coefficient. Oxygen, by its diffusion characteristics in living organisms, has a diffusion coefficient of 1. The diffusion of other gases is measured in relation to oxygen [24]. Table 2 lists the diffusion coefficient of some gaseous components of air.

The concentration of a gas in a solution depends on the solubility coefficient; the gases which are dissolved in water in larger amounts have a greater solubility coefficient.

A change in that solubility is an important factor for determining the risk of air microemboli [1,9,15,24,25].

Oxygen and carbon dioxide have high solubility in blood while nitrogen has low solubility and can, therefore, remain in the blood in the form of gas for 48 hours [9].

According to Boyle’s and Graham’s laws, the speed and solubility of a gas in a liquid is directly proportional to the temperature and the average pressure applied to it and inversely proportional to the square root of its molecular weight, i.e., the greater the molecular weight of the gaseous solute, the lower the diffusion rate, as well as the gas solubility [12, 25,26].The N2 has the highest partial pressure, both in the air and in the blood, and has little coefficient of solubility, characteristics that make it the main gas inside the bubbles formed in the blood.

LITERATURE REVIEW Transcranial Doppler The use of transcranial Doppler (TCD) made it possible to detect the occurrence of microbubbles in the circulation [12].

The TCD allows continuous measurement of blood flow velocity in cerebral arteries and is able to pinpoint echogenic signals of solid and gaseous origin [5,12,13].

The detection of gaseous microemboli (GME) by application of TCD has been described by several authors among different groups of patients for its accuracy. Newer models have the ability to qualify and quantify the occurrence of microbubbles as the EDAC ® quantifier (Luna Technologies, USA) [21-23] and Gampt BC200 (GAMPT mbH, Germany) [16], which, according to the authors, has sufficient sensitivity to identify microbubbles with a diameter of 10ìm and count up to 1000 microbubbles per second in streams with 0.2 to 6 L/min [21-23].

The physiology of blood gases CPB is an artificial cardiopulmonary bypass in which the flow of blood, responsible for transporting oxygen is produced by a peristaltic or centrifugal pump, being that the peristaltic generates pulsatile flow hydrodynamically (not physiologically) and the centrifuge generates a continuous flow, where the gaseous exchanges are performed by a membrane oxygenator which mimics the function of the pulmonary dynamics of exchange, namely by diffusion. The diffusion of a gas depends on the pressure gradient between the means of the gas exchange. Thus, Table 1. Atmospheric air composition Atmospheric gases Concentration Nitrogen 78.62% Oxygen 20.84% Carbonic gas 0.04% Water vapor 0.50% Total 100%

Partial pressure(P) 597 mmHg 159 mmHg 0.3 mmHg 3.4 mmHg 760 mmHg

Table 2. Diffusion coefficient of the gases Gas Oxygen Carbonic gas Carbon Monoxide Nitrogen Helium

Coefficient 1 20.3 0.81 0.53 0.95

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Decompression sickness Decompression sickness is caused by nitrogen bubbles that expand blood or tissue and can cause gaseous microemboli. It occurs in divers returning from greater depths of immersion without appropriate decompression due to changes of pressure and solubility of nitrogen (N2) in blood and tissues, causing air embolism. Severe cases are treated with hyperbaric oxygen therapy (HBOT) [27,28].

Table 3. U.S. Navy Treatment Table for Decompression Sickness Pressure Time(min) FIO2 PO 2 PN 2 Total 20 100% 2280 0 0:20 3 ATA 21% 479 1801 0:25 3 ATA 5 2280 0 0:45 3 ATA 20 100% 0 1:15 3-2 ATA 30 100% 2280-1520 2 ATA 5 21% 319 1201 1:20 2 ATA 20 100% 1520 0 1:40 2 ATA 5 21% 319 1201 1:45 2-1 ATA 30 100% 1520-760 0 2:15

Reis EE, et al. - Gaseous microemboli in cardiac surgery with cardiopulmonary bypass: the use of veno-arterial shunt as a preventive method

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Hyperbaric Oxygen Therapy has many applications, including treatment of decompression sickness, carbon monoxide poisoning and arterial embolism. The treatment is performed in an enclosed chamber where the patient is subjected to pressures ranging up to 3.0 atmospheres absolute pressure (ATA). At these pressures, the concentration of O2 in the body is increased by up to 1900%, and PaO2 higher than 2000 mmHg in sessions lasting 20 to 30 minutes and as a consequence the PaN2 is reduced to minimum values, as shown in Table 3 for Treatment of Decompression Sickness type 1 from the United States Navy.

Murphy et al. [29], between 1970 and 1984, treated 16 patients for embolism, of which 2 cases were for embolism during a CPB. Guy et al. [30] succeeded in treating a patient with HBOT who had suffered large gaseous emboli during a cardiac surgery. Ziser et al. [31] used HBOT to treat cerebral arterial embolism in 17 patients undergoing CPB. Grist [28], based on the use of HBOT suggested pure O2 in CPB in order to treat and prevent N2 microemboli. The analogy made by Grist between the hyperbaric chamber and the oxygenation chamber of the membrane oxygenator shows a resemblance in general characteristics of closed systems where there is the possibility of using pure oxygen and reduce PaN2.

The low pressure of the nitrogen in the blood promotes the tendency of the solubilization of this gas in the formed microbubbles.

demonstrate that the shunt could minimize the inflammatory response induced by cpb. The concept was based on the physiology of fetal circulation, where blood circulating in a fetus is at its greatest volume, a mixture of oxygenated and non-oxygenated blood.

In fetal circulation the only oxygenated blood reaches the fetus from the placenta exclusively by umbilical vein to the point of confluence with the inferior vena cava through the ductus venosus. The mixing of oxygenated and non-oxygenated blood with SaO2 = 62% in the thoracic aorta is sufficient for the fetus because their metabolic needs are reduced [36]. Moraes [37] published a comparative where he noted that there was less bleeding and a lesser need for transfusions in the group using veno-arterial shunts. This concept is applied in the manufacture of oxyshunt ÂŽ oxygenators (Instrumental Zammi, Duque de Caxias, Rio de Janeiro, Brazil).

By observing this system based on the physiology of pulmonary shunts, which also occurs between arterial and mixed venous blood, we notice an important relationship. The pulmonary shunt is defined as a disturbance in the pulmonary ventilation-perfusion relation, where a fraction of inadequately ventilated pulmonary blood [38,39] follows without sustaining gas exchange, as illustrated in Figure 1. This non ventilated blood removes some oxygen from the oxygenated blood, which results in a slight reduction in arterial PO (PaO2), hemoglobin oxygen saturation (SaO2) and, consequently in arterial oxygen content (CaO2) (Figures 2 and 3).

Hyperoxia The oxygenation of blood during infusion corresponds to a PO2 above 100mmHg and below 200mmHg, called normoxia. Its maintenance occurs according to the offer of greater or lesser fraction of inspired oxygen at (FIO2) in the gas line connected to the oxygenator during CPB. Hyperoxia is defined as a high concentration of oxygen in the blood, with this condition being produced by the oversupply of oxygen.

Hyperoxia can produce reperfusion injury, excessive production of free radicals [32,33] and even exposure to the toxic effects of oxygen [34]. The use of hyperoxia in CPB is considered unnecessary by most perfusionists. Toraman et al. [35] showed that between 35 and 45% FI02 during CPB is sufficient to allow oxygen extraction safely.

Veno-arterial shunt Moraes [38] evaluated the use of a diversion of venoarterial blood. This deviation was done by a bypass connecting the venous line before entering the oxygenator to an arterial line, which allowed the diversion of part of the circulation, so that a fraction of blood flow was not passed through the oxygenation chamber and returned to the normal circuit system after the oxygenator. This author aimed to reduce the volume of blood in contact with the membrane oxygenator, as shown in Figure 1. The objective was to

Fig.1 â&#x20AC;&#x201C; Schematic representation of the CPB circuit, extracted from the publication

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Fig. 3 - Extracted from Guyton, it shows PO2 variations in pulmonary capillary blood, arterial blood and systemic capillary blood, whereby the effect of venous mixture is observed.

Fig. 2 - Adapted from Essentials of oxygenation, T. Ahrens, 1993

When applying this equation using parameters taken from a cardiopulmonary bypass with an oxygenator, with veno-arterial shunt in use, this relationship is as follows:

In a normal, healthy individual, the physiological shunt represents 2-4% of the heart debt [1], the larger the fraction of the shunt, the lower the arterial oxygen content (CaO2) The pulmonary shunt fraction is measured by the classical shunt equation [38,39].

Qs/Qt = (CcO2 – CaO2) / (CcO2-CvO2) Where: Qs: Shunt Flow Qt: Total blood flow Qs/Qt: % of blood flow that is diverted to the shunt CcO2: Content of the O2 capillary CaO2: Arterial content of O2 CvO2: Venous content of O2 Calculations CcO2 = (Hb . 1.34 %ScO2) + (0.003 . PaO2) CaO2 = (Hb . 1.34 %SaO2) + (0.003 . PaO2) CvO2 = (Hb . 1.34 %SvO2) + (0.003 . PaO2) CcO2, CaO2 and CvO2 are given in ml of O2 by 100 ml of blood (ml/100ml).

We have: Qs/Qt = (Cox. O2 – CaO2) / (Cox.O2 – CvO2), the result is given as a % of total blood flow.

Qs/Qt = [(Hb.1.34.%Sox.O2)+(0.003.760 mmHg)] – [(Hb.1.34. %SaO2) + (0,003.PaO2)] / [(Hb. 1.34.%Sox.O2) + (0.003.760 mmHg)] – [(Hb.1.34.%SvO2) + (0.003.PvO2)] = Qs/Qt = [(10 g/dL.1.34.1) + (0.003.760 mmHg)] - [(10g/ dL.1.34.1) + (0.003.100 mmHg)] / [(10 d/L.1.34.1) + (0,003.760 mmHg)] - [(10d/L.1.34.0.75) + (0.003.40 mmHg)] = Qs/Qt = [15.5] – [13.7] / [15.5] – [10.17] = Qs/Qt = 1,8 / 5,33 = Qs/Qt= 0.33 or 33%.

Admitting Qt = 5 L/min, Qs = 0.33 x 5 L/min = 1.65 L/min. Or that is, for Qt = 5 L/ min, um Qs = 1.65 L / min will be sufficient to control hyperoxia generated with FIO2 = 100%.

Applying the equation, considering: PaO2= 100 mmHg SaO2= 100% PvO2= 40 mmHg SvO2= 75% Hb= 10g/dL FIO2= 100% (pure oxygen) Atmospheric Pressure =760 mmHg, at sea level.

Replacing the CcO2 with Cox.O2 (blood content in the blood after passing through the membrane) and ScO2 with Sox.O 2 (oxygen saturation after passing through the membrane).

In other words 33% of the perfusion flow passing through the shunt permits an adequate perfusion with the hyperoxia duly controlled.

The idea then occurred to evaluate the prospect of the shunt to control the pure O2 induced hyperoxia, as this could prevent the formation of microbubbles in CPB and this relationship seems to elucidate the question of microbubbles of nitrogen.

We compared the functional anatomy of the ventilatory unit shown in Figure 4 with the anatomy of the Oxyshunt ® Zammi oxygenator (Figure 5).

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Fig. 4 - Dynamics of the blood as it travels the pulmonary capillary.

Adapted from Essentials of oxygenation, T. Ahrens, 1993

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The control of venous blood flow (shunt) is made by a clamp mounted on the shunt line, this clamp has an adjustable diameter control line and it is driven by pulse oximetry in the arterial and venous lines, where the targets are 95 and 75% of arterial and venal saturation respectively with a 100% FIO2 oxygen gas/arterial blood flow of 1:1 Thus, the removal of CO2 by the membrane behaves in the same manner as in oxygenators that utilize a gas mixer.

An â&#x20AC;&#x153;onlineâ&#x20AC;? Oximetry is necessary due to the risk of hypoxia produced by an inadvertently kept larger fraction of shunt and by the contrary, hyperoxia.

Both the veno-arterial shunt and the pulmonary shunt permit the reduction of blood passing through the exchange membrane. This diverted blood does not receive oxygen, and as it returns to the arterial line, it mixes with the blood that passed through the membrane. At the moment of the mixture there is a gradient of PaO2 that is balanced by diffusion in a short segment of arterial line, thus hyperoxia does not occur by the use of pure oxygen avoiding the possible occurrence of reperfusion injury and the harmful effects of excess O2.

Table 4. Partial pressure of Nitrogen Partial pressure Air Arterial blood PO 2 158 100 PCO2 0.3 40 PN 2 596 573 PH 2 O 5.7 47 Total 760 760

Fig. 5 - Dynamics of the blood in the Oxyshunt oxygenator. Schematic design

The dynamics of blood in the oxygenator follow the principles of hemodynamics, the passage of blood by the membrane area produces high strength, and the tendency of the flow segment is to follow by the segment of least resistance (due to the shunt deviation), which makes necessary a constraint mechanism to control the flow of blood running through the shunt. The deviation causes a smaller portion of blood flow to traverse the membrane so there is a tendency of a lower incidence of hemolysis.

Venous blood 40 46 573 47 760

Tissue 40 46 573 47 706

Nitrogenation Nitrogen gas is responsible for arterial embolization, this occurs because of its low solubility coupled with its high concentration in blood as well as in tissue (Table 4).

The partial pressure of nitrogen in the blood is 573 mmHg, according toTable 4.

The use of pure oxygen produces denitrogenation of blood, reducing PaN2 and hence the content of dissolved nitrogen in the body, Tovar et al. [9], and increases the window of oxygen, or that is, with lowered PaN2, the blood has a lower content of dissolved nitrogen, which allows oxygen to fill this empty space formerly occupied by nitrogen.

With the low pressure of N2, there is greater tendency for solubilization of the N2 microbubbles in blood and this still prevents the microbubbles which may be formed in the vascular system. With this concept Berry & Myles [40] produced alveolar denitrogenation with ventilation to a FIO2 at 100%, and recorded FEO2 (Fraction expiratory O2) of 96% after 3 minutes exposure, this experiment shows that this process is rapid and probably happens in the same condition in the membrane oxygenator.

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Georgiads et al. [41] subjected 185 patients who were mechanical valve carriers to ventilation with FIO2 to 100% while he monitored microembolic events produced by cavitation valves with TCD. This study showed a significant decrease in the production of microbubbles compared with room air ventilation, suggesting that the principal source of gas embolism in those patients consisted of N2 bubbles.

Rodriguez & Belway [42] developed a flow chart reproduced here, which relates the mechanisms involved in the events that follow up to the cerebral embolism produced by cavitation (Figure 6).

Among the mechanisms mentioned are, complement activation, adhesion of plasma proteins and platelet destruction leading to thrombus formation and vascular injury and embolism from the formation of nitrogen bubbles in the blood.

In the description of Tovan et al.[9], who sees a proportional relationship between volume, area and diameter of the Nitrogen microbubbles formed (Table 5), where gas

bubbles enter the bloodstream in dynamic equilibrium with the dissolved gas in plasma, it is noted that these will be enlarged or reduced according to the partial pressure of the gas in solution [11].

However, using the veno-arterial shunt with the flow fraction described above will cause the denitrogenation produced to break this balance and the microbubbles tend strongly to dissolve in the blood.

For the situation of microbubbles formed which passed through the veno-arterial shunt (e.g., bubbles formed in the venous reservoir), when they encounter the arterial blood which passed through the membrane (denitrogenized), there is a strong tendency to dissolve.

Similarly, possible O2 microbubbles formed in the oxygenator will be dissolved by mixing with the blood passing through the shunt with low PaO2, as shown in the flowchart (Figure 7).

Fig. 6 - The flowchart shows a sequence of events resulting in the formation of cavitation microbubbles that culminates with the final outcome embolism, the same sequence of events can occur during CPB

Fig. 7 - The flowchart shows how the shunt venoarterial could control hyperoxia used to produce denitrogenation of blood

Table 5. Relationship between diameter, volume and surface area of the N2 microbubble Bubble Bubble Number Volume of bubble x Bubble diameter volume of Number of bubbles surface 1 cm = 10 mm 0.5 ml 1 0.5 ml 3.14 cm2 0.1 cm = 1 mm 0.5 µl 1000 0.5 ml 3.14 cm2 4 0.01 cm 5x10 µl 1000000 0.5 ml 31.4 µm2 0.001 cm 5x107 µl 1000000000 0.5 ml 314 µm

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Surface x Number of bubbles 3.14 cm2 31.4 cm2 314 cm2 3140cm2

Reis EE, et al. - Gaseous microemboli in cardiac surgery with cardiopulmonary bypass: the use of veno-arterial shunt as a preventive method

RESULTS The denitrogenation promoted by hyperoxia prevents the formation of microbubbles. The veno-arterial shunt as described by Moraes obeys the physiology of pulmonary shunts and can control hyperoxia used to produce denitrogenation of blood during CPB according to the flowchart in Figure 7.

DISCUSSION Since the first oxygenator developed by Gibbon to current models, many problems inherent to the CPB were identified, problems related to effectiveness, such as adequate oxygenation, removal of CO2 [42], and others related to safety such as inflammatory activation trauma and blood microemboli.

This evolution of new knowledge minimized the deleterious effects of CPB and with the addition of accessories such as arterial filters and bubble detectors; it has reduced the morbimortality in cardiac surgery procedures with CPB [38,43-45]. However, the incidence, still frequent of neurological complications remains a challenge because, despite all the advances, neurologic complications still occur and are causes of serious damage [4]. Many studies have been conducted with the accuracy of the TCD, which has made it possible to quantify and qualify the occurrence of microbubbles in both the CPB circuit as well as in cerebral arteries and to measure the resulting GME. It is known that microbubbles have nitrogen gas as their main component. The removal of N2 from blood is well documented; the denitrogenation decreases the tension of N2 pressure, so the bubbles thus formed are dissolved. This occurrence of denitrogenation implies the use of pure O 2 in oxygenation which would lead to hyperoxia and its toxic effects, but that can be avoided in cardiopulmonary bypass procedures with the use of venoarterial shunts in the oxygenator.

Weitkemper et al. [3] stated that “gaseous microemboli are still an unsolvable problem of the CPB circuit.” However, if we consider the information presented here, we believe that this paradigm dissolves with the content presented here.

The veno-arterial shunt that at the time was developed with the goal of reducing inflammatory activation in CPB [38] and was not associated with denitrogenation by the use of pure O2, which appears to be its main advantage and benefit to the patient. And, moreover, it has proven to be a simple and practical method, provided it is properly controlled, the benefit of which has great importance for those who require the use of CPB in heart and organ management operations, with greater cost savings, and mainly eliminating the complications of air microemboli during cardiopulmonary bypass, as well as an evolution in practice. This work sheds light on this possibility and we

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suggest that randomized controlled trials are effected to confirm the benefits of the possibility of damage control and vascular complement activation cited by Rodriguez et al. [13].

CONCLUSION It was our objective to evaluate whether the use of venoarterial shunts in membrane oxygenators can prevent the occurrence of microemboli in CPB. We used the integrative review method for this purpose, allowing the freedom to relate publications of different methodologies in order to establish a well founded and logical relationship. It is concluded that literary findings support the hypothesis that the shunt, duly controlled, prevents unchecked gaseous microemboli, facilitating the solubilization of microbubbles of nitrogen arising from the operation according to the description of this method found in the literature, while at the same time, the shunt prevents hyperoxia. However the use of an oximeter line (mainly venous) is indicated to provide adequate control flow of the shunt.

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33. Caputo M, Mokhtari A, Rogers CA, Panayiotou N, Chen Q, Ghorbel MT, et al. The effects of normoxic versus hyperoxic cardiopulmonary bypass on oxidative stress and inflammatory response in cyanotic pediatric patients undergoing open cardiac surgery: a randomized controlled trial. J Thorac Cardiovasc Surg. 2009;138(1):206-14.

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41. Georgiadis D, Wenzel A, Lehmann D, Lindner A, Zerkowski HR, Zierz S, et al. Influence of oxygen ventilation on Doppler microemboli signals in pacients with artificial heart valves.

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SCIENTIFIC UPDATE

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Noninvasive mechanical ventilation in the postoperative cardiac surgery period: update of the literature Ventilação mecânica não-invasiva no pós-operatório de cirurgia cardíaca: atualização da literatura

Lucas Lima Ferreira1, Naiara Maria de Souza2, Ana Laura Ricci Vitor2, Aline Fernanda Barbosa Bernardo2, Vitor Engrácia Valenti3, Luiz Carlos Marques Vanderlei3

DOI: 10.5935/1678-9741.20120074 Abstract This study aimed to update knowledge regarding to noninvasive ventilation (NVI) on postoperative of cardiac surgery in addition at investigating if exists superiority of any modalities NVI in relation to the others. The literature review was performed on the period between 2006 and 2011, on PubMed, SciELO and Lilacs databases crossing the keywords: artificial respiration, continuous positive airway pressure, intermittent positive-pressure ventilation, cardiac surgery and their corresponding in English. Based on the criteria adopted, nine articles were selected being six of them use NVI, through the modalities such as continuous positive airway pressure, positive pressure with bilevel pressure and intermittent positive-pressure ventilation in postoperative of cardiac surgery; only three of them performed comparisons between different modalities. The NVI modalities that were described on the literature had showed satisfactory results. A few studies compare different NVI modalities; however some

RBCCV 44205-1405 of them showed superiority in relation to the others, such as the intermittent positive-pressure ventilation to threat hypoxemia and to positive pressure with bilevel pressure to increase oxygenation, respiratory rate and heart rate in these patients, when compared with other modalities.

Descriptors: Continuous positive airway pressure.

Respiration, artificial. Pulmonary ventilation. Postoperative period.

Resumo Este estudo objetivou atualizar os conhecimentos em relação à utilização da ventilação mecânica não-invasiva (VMNI) no pós-operatório de cirurgia cardíaca e identificar se há indícios da superioridade de uma forma de modalidade de VMNI em relação à outra. Foi realizada revisão da literatura entre 2006 a 2011, a partir das bases de dados

1. Physiotherapist, Master’s Degree in Physiotherapy at Faculty of Sciences and Technology (FCT) – State University of São Paulo (UNESP), Presidente Prudente – SP. 2. Full Professor of the Strictu Sensu Postgraduation Program in Physiotherapy at Faculty of Sciences and Technology (FCT)/ UNESP. 3. PhD. Professor of the Post-graduate studies in FCT/UNESP, Presidente Prudente, SP, Brazil.

Simonsen, 305, Centro Educacional – 19060-900, Presidente Prudente – SP, Brazil.

This study was carried out at Faculty of Sciences and Technology of the State University of São Paulo (FCT/UNESP), Rua Roberto

Article received on June 11th, 2012 Article accepted on August 14th, 2012

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Correspondence address: Lucas Lima Ferreira R. Roberto Simonsen, 305, Centro Educacional.

19060-900, Presidente Prudente, SP Fone: (18)3229-5819 e-mail: lucas_lim21@hotmail.com

Ferreira LL et al. - Noninvasive mechanical ventilation in the postoperative cardiac surgery period: update of the literature

Abbreviations, acronyms & symbols BiPAP® CS CPB CPAP VC CO CVD DeCS HR CRP IS RespF MeSH RM PO CABG IPPB VPR MV NIV

Bi-level positive airway pressure Cardiac surgery Cardiopulmonary bypass Continuous positive airway pressure Vital capacity Cardiac output Cardiovascular diseases Descriptors in Health Sciences Heart rate Conventional respiratory physioterapy Incentive spirometry Respiratory failure Medical Subject Headings Recruitment maneuver Postoperative Coronary artery bypass grafting Intermittent positive pressure breathing Ventilation perfusion rating Mechanical ventilation Noninvasive mechanical ventilation

INTRODUCTION Cardiovascular diseases (CVD) are among the leading causes of death in developed countries and their incidence has increased in epidemic form in emerging countries [1].

Among the options for the treatment of these diseases, cardiac surgery (CS) has shown good results, contributed to rising expectations and improving the quality of life of patients with CVD [1-3].

Changes in lung function may occur after CS, which are responsible for increased postoperative (PO) morbidity and mortality [4] and are resulting from multifactorial interaction between anesthesia, surgical trauma, cardiopulmonary bypass (CPB), cardiac arrest, time of surgery, duration of mechanical ventilation (MV) and pain, which may lead, among others, to decrease in functional residual capacity, increased intrapulmonary shunt and enlargement of the alveolar-arterial oxygen [4,5].

In this context, noninvasive ventilation (NIV) has been important in the treatment of POCS, because its use improves alveolar ventilation and gas exchange, decreases ventilatory work, increases lung volumes and decreases

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PubMed, SciELO e Lilacs, utilizando os descritores respiração artificial, pressão positiva contínua nas vias aéreas, ventilação com pressão positiva intermitente e cirurgia cardíaca, e seus correspondentes na língua inglesa, os quais foram pesquisados em cruzamentos. A partir dos critérios adotados, foram selecionados nove artigos, dos quais seis demonstraram aplicações de VMNI, por meio de modalidades como pressão positiva contínua nas vias aéreas, pressão positiva com dois níveis pressóricos e respiração com pressão positiva intermitente, no pós-operatório de cirurgia cardíaca, e, três realizaram comparações entre as diferentes modalidades. As modalidades de VMNI descritas na literatura foram utilizadas com resultados satisfatórios. Estudos que comparam diferentes modalidades são escassos, contudo alguns demonstraram superioridade de uma modalidade de VMNI, como é o caso da respiração com pressão positiva intermitente na reversão da hipoxemia e da pressão positiva com dois níveis pressóricos na melhora da oxigenação, da frequência respiratória e frequência cardíaca desses pacientes, em comparação a outras modalidades.

Descritores: Pressão positiva contínua nas vias aéreas.

Respiração artificial. Ventilação pulmonar. Período pósoperatório.

the duration of mechanical ventilation, avoiding reintubation and, as a consequence, reducing the length of permanence in intensive care units [6-10].

Furthermore, the application of NIV reduces preload by reducing the venous return, reduces afterload in the left ventricle by reducing its transmural pressure and increases cardiac output (CO), which leads to improved heart performance as a pump [6.11].

The modalities of NIV with positive pressure used in the treatment of postoperative pulmonary complications in the POCS described in the literature are ventilation with continuous positive airway pressure (CPAP), BI-level Positive Airway Pressure (BiPAP ®) and intermittent positive pressure breathing (IPPB) [12,13]. The superiority of one modality over another NIV has not been clearly established in the literature [13].

In view of the above considerations, we understand the importance of studies that add new elements in the literature regarding this issue. Therefore, we aimed to update the literature regarding the use of NIV in the POCS and to identify if there is evidence of the superiority of NIV modality.

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Ferreira LL et al. - Noninvasive mechanical ventilation in the postoperative cardiac surgery period: update of the literature

METHODS Search strategy The revisions were performed on April 2012, the references used were situated between January 2006 and December 2011. The Pubmed, Lilacs and SciELO databases were searched using the following subject keywords: artificial respiration, continuous positive airway pressure, intermittent positive-pressure ventilation, cardiac surgery.

These words were defined by the Health Sciences Descriptors (DeCS) and their corresponding in English Medical Subject Headings (MeSH).

The term noninvasive ventilation, while not considered a descriptor by the NLM - MESH, was included due to its wide use as a keyword. All references were also reviewed for completion of the research. The studies were selected by a reviewer and supervised by a senior reviewer.

Exclusion and Inclusion Criteria We included studies published in the last five years, in English and Portuguese, with humans over 18 years old with heart diseases who have undergone some type of surgical intervention. We included randomized and nonrandomized controlled trials.

Abstracts of dissertations or academic thesis, studies in children and adolescents, and studies using NIV in other pathological conditions other than heart were excluded.

Selection Strategy We initially performed the screening of titles related to the topic. This selection was based on titles that dealt as main idea: the application of NIV in POCS, several types of NIV used, the performances of physiotherapy on cardiac patients undergone CS and, finally, to present evidence of some NIV term information related to this word such as ventilation with continuous positive airway pressure, BI-level Positive Airway Pressure. At the end of the search, we excluded repeated titles, as this was performed in several databases. Then we read detailed summaries of articles in order to select those that addressed only the application of NIV in POCS. We excluded abstracts not related to the issue, the full texts were assessed and those that did not fit the exclusion criteria were included as the final result of the search.

Data Analysis Data were qualitatively assessed and presented in tabular form with the description of the following profile: author and year of study, clinical characteristics of the population, the study objectives, ventilatory mode applied, variables and conclusions found.

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RESULTS The search in the databases resulted in 1447 titles. The first selection eliminated 1398 titles. Then we proceeded to assess the content of the summaries of the remaining 49 studies, of which 38 were eliminated for not meeting the criteria previously established. The 11 remaining articles were read in full and composed the review.

We found eight studies that used some modality of NIV in the POCS, which are described in Table 1.

Only three of the articles compared different NIV modalities in the POCS and were used to assess possible evidence of superiority of one NIV technique. These studies are described in Table 2.

DISCUSSION Application of NIV in the CSPO. Regarding the application of NIV in the POCS, eight studies demonstrated its application through the following modalities: CPAP, BiPAP 速, IPPB + PEEP and PSV, and most of the studies assessed showed positive evidence of the implementation of those modalities in the cardiac PO patients.

Figueiredo et al. [14] compared the rates of gas exchange after surgery in patients undergoing coronary artery bypass grafting (CABG) with or without CPAP during cardiopulmonary bypass (CPB) and found that the use of CPAP, although it resulted in better values in PaO2/FiO2 30 minutes after CPB, it showed no significant sustained effect on postoperative pulmonary gas exchange. The authors reported that was not possible to demonstrate that the application of CPAP during CPB prolonged beneficial effect on gas exchange during the PO. The authors cited as limitation the small population sample used, which may have influenced the results.

Other authors [15] assessed the efficacy of prophylactic CPAP, performed with a nasal mask at a pressure of 10 cmH2O airway for six hours, compared with standard treatment in patients undergoing elective CS, and found that the prophylactic CPAP improved oxygenation pressure, reduced the incidence of pulmonary complications and decreased the rate of readmission in the intensive care unit.

The authors attributed these results to airway pressures high enough (10 cmH2O) throughout the respiratory cycle and maintaining such pressure for longer periods of time (six hours), which led to reduction in atelectasis.

The pulmonary effects of CPAP with or without intermittent recruitment maneuver (RM) in patients after CABG surgery were assessed by a randomized clinical trial, in which it was found that the RM provided higher blood oxygen level during the MV and after extubation compared

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Table 1. Studies using NIV in PO CS, according to year of publication, from January 2006 to December 2011, in the Pubmed, Lilacs and SciELO databases.

Author and year

Population profile

Franco et al. [17] 2011

26 patients (17 males).

BIPAP group (n = 13) with respiratory physiotherapy associated with BIPAP for 30 min.

Control group (n = 13): only respiratory physiotherapy.

Mazullo Filho et al. [6] 2010

Modality

Objectives

Variables analyzed

Conclusions

BIPAP

To evaluate compliance, safety and efficacy of NIV related to respiratory physiotherapy in the immediate CABG PO.

Hemodynamic parameters (HR, BP, SpO2), respiratory variables (VC, MV and TV), blood gas and spirometric variables (MIP and MEP).

The use of BIPAP associated with respiratory physiotherapy was safe and well accepted by patients and increased VC.

32 patients in the immediate PO CS. Control Group (n = 18): aged 61.0 ± 16.2 years old, 11 male.

Experimental Group (n = 14): aged 61.5 ± 9.4 years old, 8 males.

PSV+PEEP

To verify the effect of preventive NIV on the immediate PO CS following its impact until the sixth day of hospitalization.

Hemodynamics (HR, BP, SpO2);Blood gas analysis (pH, PaO2, PCO 2, HCO3);FR;Spirometric variables (VC, MV and TV)

The NIV was effective on the PO CS group studied, because it increased VC, decreased RR, prevented the RF post extubation and reduced rates of reintubation.

Zarbock et al. [15] 2009

468 patients of both genders: Prophylactic CPAP group (n = 232): 10 min for nasal CPAP at 10 cmH2O for 6h.

Control group (n = 236): 10 min of intermittent nasal CPAP at 10 cmH2O every 4h.

CPAP

To evaluate the efficacy of CPAP with a nasal mask compared with standard treatment in patients undergoing elective CS.

Pulmonary complications, PaO2/ FiO2, nosocomial pneumonia, reintubation rate, readmission to the ICU or coronary care unit.

The administration of CPAP after CS improved arterial oxygenation, reduced the incidence of pulmonary complications and readmission rate in the ICU, it was suggested as a useful tool to reduce pulmonary morbidity following elective CS.

Figueiredo et al.

[14] 2008

30 adult patients of both genders; CPAP group (n = 15) received CPAP during ECC. Control group (n = 15) did not receive CPAP.

CPAP

To compare the rates of gas exchange in the PO period in patients who received or not CPAP during ECC.

PaO2/FiO2;P (A-a)O2;4 moments:Pre (immediatelly after ECC), Pos (30 min after ECC), POI (12h pos-surgerya) and 1.º PO (24h).

The use of CPAP improved PaO2/FiO2, 30 minutes after ECC, however, did not result in lasting benefits in gas exchange during the PO period.

Celebi et al. [16] 2008

RM group (n = 25): RM during MV in the PO period.

RM-NIV group (n = 25): CPAP applied for 30 min every 6 h in a PO associated with RM. NIV group (n = 25): CPAP applied for 30 min every 6 h in the PO period. Control group (n = 25) received no MR nor NIV.

CPAP

To evaluate the pulmoary effects of NIV with or without RM post CABG.

Lung function tests;oxygenation index;Atelectasia through thorax x-ray.

The NIV associated with RM provided better oxygenation after CABG, it is recommended to prevent postoperative atelectasis and hypoxemia.

Mendes e BorghiSilva [18] 2006

21 patients (14 male) GPPI (n=8): respiratory exercises with RPPI associates with PI; GIF (n=13): only PI.

RPPI

To evaluate changes in LF and RMS and efficacy of two protocols on patients submitted to ECC CS.

Spirometric variables (VC, FVC, FEV1, PF, FEF25-75, PImáx and PEmáx)

Patients submitted to CS with ECC presented reduced FP and RMS. None of the treatments applied (BIPP + IF or IF) showed better results.

N = number of subjects; CABG = coronary artery bypass grafting; HR = heart rate; BP = blood pressure; RR = respiratory rate; SpO2 = oxygen saturation; TV = tidal volume; MV = minute volume; VC = vital capacity; FVC = forced vital capacity; FEV1 = forced expiratory volume at the first second; FEF25-75 = forced expiratory flow between 25 e 75%; MIP = maximal inspiratory pressure, MEP = maximal expiratory pressure; PO = postoperative day; CS = cardiac surgery; CABG = cardiopulmonary bypass grafting; VRS = valve replacement surgery, ASD = atrial septal defect; AN = aneurysm, pH hydrogen potential, O2 = oxygen, PaO2 = arterial partial pressure of O2, PCO2 = arterial partial pressure of carbon dioxide, HCO3 = bicarbonate, P (Aa) O2 = alveolar-arterial O2; ARF = acute respiratory failure; ICP = intracranial pressure; CT = computed tomography; U.S. = ultrasonography; h = hours; ICU = intensive care unit; DM = diabetes mellitus; HBP = hypertension; CAD = coronary artery disease; ECG = electrocardiography; RM = recruiting maneuver; GPPI = positive pressure group intermittent; PI = physiotherapy intervention; GIF = group physiotherapy intervention; LF = lung function, RMS respiratory muscle strength; NIV = noninvasive ventilation; BIPAP = pressure bi-level positive airway; PEEP + PSV = pressure support ventilation more positive end expiratory pressure; CPAP = continuous positive airway; IPPB = intermittent positive pressure breathing; ECC: Extracorporal circulation.

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Table 2. Studies comparing different types of NIV in post-cardiac surgery, according to year of publication, from January 2006 to December 2011, in the Pubmed, Lilacs and SciELO databases.

Author and year Romanini et al.

[19] 2007

Population profile 40 patients after CABG. RPPI group: (n=20; 40% female); Incentive spirometry group: (n=20; 20% dfemale)

Modality

Objectives

Variables analyzed

Conclusions

RPPI (RM); Incentive spirometry

To analyze the physiotherapeutic effect of IPPB and incentive spirometry on patients submitted to CABG.

Age, weight, height, body mass index, surgical time, CABG time, number and location of drains, SpO2; TV, MIP and MEP.

IPPB was more efficient in reversing hypoxemia earlier compared to the incentive spirometry. To improve the strength of respiratory muscles, the incentive spirometry was more effective.

Coimbra et al.

[20] 2007

57 patients: 22 submitted to CABG, 13 valvar replacement, 5 aneurism correction or aortic dissection, 3 CPT and 15 combined surgeries.

Group A: PS + PEEP through NIV (n=19); Group B: CPAP (n=19); Group C: BiPAP (n=19)

CPAP; PS + PEEP; BiPAP

To verify ventilatory responses, oxygenation and hemodynamics in patients with RF after cardiac surgery, seeking success variables and compare the different modalities of NIV.

Respiratory parameters (RR); Oxygenation parameters(pH, PaO2, PCO2 and SpO2); Hemodyinamic parameters (HR and MAP)

There was improvement in oxygenation, RR, and HR during the application of NIV. In older patients with higher baseline RR and HR, NIV was not sufficient to reverse RF. Arrangements with two pressure levels showed better results.

Müller et al. 2006 [21]

40 patients submitted to CABG, 33 male and 7 female.

CPAP group (n=20); IPPB group (n=20)

CPAP; IPPB (MR)

To compare the result from the application of CPAP and the application of IPPB in patients after cardiac surgery.

Blood gas parameters (pH, PaO2, PCO2 and SpO2); Respiratory parameters (TV, MV and RR); Physical examination (dyspnea and assessory muscle activity); Thorax x-ray (medical diagnosis)

Both resources maintained values of PO2, PCO2 and SpO2 within normal limits.

For the pulmonary reexpansion with less imposed workload, the MR was more effective and presented lower levels of dyspnea, accessory muscle activity and FR.

N = number of subjects; CABG = coronary artery bypass grafting; HR = heart rate; MAP = mean arterial pressure; RR = respiratory rate; SpO2 = oxygen saturation; TV = tidal volume; MV = minute volume; MIP = maximal inspiratory pressure, MEP = maximal expiratory pressure; CPT = chronic pulmonary thromboendarterectomy; pH = hydrogen potential; O2 = oxygen; PaO2 = arterial partial pressure of O2, PCO2 = arterial partial pressure of carbon dioxide; RF = respiratory failure; NIV = noninvasive ventilation; BIPAP = pressure bi-level positive airway; PSV + PEEP = pressure ventilatory support more positive end expiratory pressure; CPAP = continuous positive airway; IPPB = intermittent positive pressure breathing; RM = Müller resuscitation

with other interventions. Oxygenation was better in groups using CPAP compared to the control group and pulmonary function of NIV groups on the 2nd postoperative day was better than the other groups. The authors reported that CPAP has been used intermittently to avoid gastric distension, restricted oral intake, nausea and vomiting, and that NIV improved radiological scores of atelectasis [16].

A randomized clinical trial assessed the safety and compliance of preventive application of BiPAP ® in spontaneous mode with IPAP 8-12 cmH2O and EPAP at 6 cm H 2O, twice daily for 30 minutes associated with conventional respiratory therapy (CRT) in patients in the 450

immediate postoperative [17]. The authors found that the application of BiPAP ® was beneficial to restore lung function, especially vital capacity (VC), safely, and well accepted by patients, due to higher comfort with the sensation of pain during the execution of CRT and the use of BiPAP ® leads to an increase in the incursion chest with consequent improvement in the efficacy of cough, increased secretion clearance and airway patency, by improving the peak flow [17].

The preventive efficacy of NIV in the pressure support ventilation combined with positive end expiratory pressure (PEEP + PSV) for two hours, was assessed in the immediate

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POCS in a randomized controlled trial, which showed significant results in hemodynamic and ventilatory variables assessed after NIV compared to post-extubation [6]. The hemodynamic benefits were attributed to the increase in VC, accompanied with increase in lung volume and decreased respiratory work, and maintenance of HR within the normal range [6].

Most studies assessed positive evidence of the NIV application in POCS such as: improvement in arterial oxygenation [14-16], cough improvement [15,16], reestablishment of lung function with increased VC [6 , 17], reduced incidence of pulmonary complications [15], benefic effects on readmission rates in intensive care units [15], and also increased clearance of secretions and airway permeability [6.15].

providing a synchronism between the operator and the patient, respecting the patient’s respiratory cycle and offering a perfect fit of the mask, causing higher VC gain and pulmonary expansion [21].

In summary, comparative studies have shown some results that point to signs of better effects with the application of a NIV modality over the other. However, the extrapolation of these data for all patients undergoing CS does not present strong scientific evidence.

Comparison of different modalities of NIV in the POCS We found only three studies that indicated any superiority of one NIV modality over another. Assessing hemodynamic and ventilatory parameters induced by the application of IPPB and incentive spirometry (IS) in patients undergoing CABG, Romanini et al. [19] showed that IPPB was more efficient in reversing hypoxemia earlier, and it was also more effective to improve the strength of the respiratory muscles. According to the authors the IPPB is a passive process of lung expansion that does not require active work of breathing, which in the initial stage of recovery from surgery may lead to increased pain, restrict respiratory expansion and change the ventilationperfusion (V/Q), factors that may lead to the hypoxemia development [19].

Another comparison of different modalities of NIV in POCS was performed in patients with hypoxemic respiratory failure (RF), who were randomized in the CPAP, PSV + PEEP or BiPAP® modalities. Oxygenation variables and respiratory rate showed improvement only in the groups with two modalities pressure levels. However, regarding the occurrence of success and failure characterized as return or no return to mechanical ventilation, there was no significant difference between the modalities. The authors attributed this mechanism to the different causes that lead to RR, that in POCS, and it presents as main causes processes collapse and pulmonary infiltrates [20].

The effects of IPPB (Müller Resuscitator [MRI]) were compared with CPAP in patients in the PO period of CABG and it was verified that, when seeking the pulmonary reexpansion with lower imposed workload, the MRI was more effective due to its faster action, with lower levels of dyspnea, respiratory rate and accessory muscle activity [21]. Leaks or air leaks are common situations in the application of CPAP, but also the possibility of aerophagia; such a situation, in MRI is suppressed by the safety valve that prevents a higher pressure,

CONCLUDING REMARKS The NIV modalities conventionally described in the literature, as CPAP, BiPAP® and IPPB were used in postoperative surgery, added to a current modality, PSV + PEEP, with satisfactory results. Studies that compare different NIV modalities are scarce, although some studies have been demonstrated to be better in the case of IPPB to reverse hypoxemia and in the case of BiPAP ® to improve oxygenation, respiratory rate and heart rate in these patients.

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15. Zarbock A, Mueller E, Netzer S, Gabriel A, Feindt P, KindgenMilles D. Prophylactic nasal continuous positive airway pressure following cardiac surgery protects from postoperative

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16. Celebi S, Köner O, Menda F, Omay O, Günay I, Suzer K, et al.

Pulmonary effects of noninvasive ventilation combined with the recruitment maneuver after cardiac surgery. Anesth Analg.

2008;107(2):614-9.

17. Franco AM, Torres FC, Simon IS, Morales D, Rodrigues AJ. Assessment of noninvasive ventilation with two levels of positive airway pressure in patients after cardiac surgery. Rev Bras Cir Cardiovasc. 2011;26(4):582-90.

18. Mendes RG, Borghi-Silva A. Eficácia da intervenção fisioterapêutica associada ou não à respiração por pressão positiva intermitente (RPPI) após cirurgia cardíaca com circulação extracorpórea. Fisioter Mov. 2006;19(4):73-82.

19. Romanini W, Muller AP, Carvalho KAT, Olandoski M, FariaNeto JR, Mendes FR, et al. Os efeitos da pressão positiva intermitente e do incentivador respiratório no pós-operatório de revascularização miocárdica. Arq Bras Cardiol.

2007;89(2):105-10.

20. Coimbra VRM, Lara RA, Flores EG, Nozawa E, Auler-Júnior JOC, Feltrim MIZ. Aplicação de ventilação não invasiva em insuficiência respiratória aguda após cirurgia cardiovascular.

Arq Bras Cardiol. 2007;89(5):298-305.

21. Müller AP, Olandoski M, Macedo R, Constantini C, Souza LCG. Estudo comparativo entre a pressão positiva intermitente (Reanimador de Müller) e contínua no pós-operatório de cirurgia de revascularização do miocárdio. Arq Bras Cardiol.

2006;86(3):232-9.

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SPECIAL ARTICLE

Reflections engendered as a practicing translator concerning the language of Anatomy Reflexões de um tradutor na área da Anatomia Humana

Alexandre Lins Werneck1

DOI: 10.5935/1678-9741.20120075

RBCCV 44205-1406

Descriptors: Terminology. Terminology as Topic. Language.

Translations.

Descritores: Terminologia. Terminologia como assunto.

Linguagem. Traduções.

For the last 30 years as a practicing translator I have been worried about the increasing indifference of students, younger teachers, and health practitioners regarding the language of Anatomy. In the early 1980s, when I started translating, translation was far easier than it is currently. I learned by doing and by seeing how others did it. In Brazil at that time, there were a few schools that taught one how to translate. Old typewriters were used to type translated texts into a huge pile of paper. Furthermore, it was easy to keep time. Presently, the translator needs to handle not only a telephone and its derivatives, a fax, a computer, but also a whopping cornucopia of software, e-mails, gadgets, and so. One turns to be less than a translator and more of a communicator [1].

Finally, presently all of us can rely on computer-aided translation that provides translators, students, and health practitioners with tools to smooth and codify their tasks. It seems rather unnecessary to say that, in my view, the human translator will always need to interfere, because what needs to be done is that the language must be adapted to the machine and not the other way around [1].

Students are no more perplexed with the many terms met with in their textbooks, lectures and demonstrations.

Anatomical terminology indicating the various parts and organs of the human body is the most basic vocabulary in medicine and serves as the convenient tools in the anatomical sciences [2]. They just memorize the terms – the current Terminologia Anatomica includes near 7000 entries – to forget it next morning and the structure it symbolizes a few days later. This disregard is understandable in recent years, once less than 10% of students, in many countries, have never done one year of Latin. In Brazil, with a language derived and the closest to the Latin, our students have not a single hour of Latin during their high school or college. It is a shame and a pity!

Moreover, you all can verify that in general, in our courses on Gross Anatomy from 500 hours devoted to lectures and lab exercises we barely have 15 minutes dedicated to the language of Anatomy. In many good textbooks with 600 or more pages dealing with the description of the structures of the human body we hardly find more than a page about the language of Anatomy. And this is amazing, because when you want to read a book in the original language that is not yours, the first thing you do is to learn the language in order to understand the text.

With Anatomy it should not be different!

1. Ph.D.; Translator / Professor of English Language, São José do Rio Preto, SP, Brazil.

Correspondence address: Alexandre Lins Werneck Rua Rio Mamoré, 287 – Aclimação – São José do Rio Preto, SP, Brazil – CEP 15091-410 E-mail: alexandrewerneck@uol.com.br Article received on July 12th, 2012 Article accepted on July 16th, 2012

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Abbreviations, acronyms & symbols AT NA BNA FCAT

Anatomical Terminology Nomina Anatomica Basiliensia Nomina Anatomica Federative Committee on Anatomical Terminology

The anatomy instructors constitute a closed group inside the Medical Sciences, and they have their own language. This language belongs to all, and it is imposed to all in order to raise a reciprocal understanding within the community without geographical or linguistic limitations.

Anatomical terminology serves as a basic communication tool in all medical fields and the Latin anatomical nomenclature has been repetitively issued and revised since 1895 [3,4]. It is worth remembering here that Anatomy uses a special vocabulary, but anatomical terminology and nomenclature must distinguished unlike in many other medical fields. According to Kachlik et al. [3], a system of terms used in a certain scientific branch is called Terminology, while a standardized system do precisely defined terms, set according to certain classification principles and containing terms created within the scope of terminology is called Nomenclature.

A name, as a word, is a phonetic-psychological entity, the union of an idea with a sound. The word exists only when the phonetic grouping, represented by letters when written, corresponds to an idea or concept to both the speaker and the listener. Being so, when we do not know the idea or concept linked with a word it becomes meaningless for us and the understanding among people using different names for the same idea is almost impossible.

And this is what I suppose happened in the beginning of Anatomy. The lack or difficulties in communication among the early anatomists led to a disorderly growth, each anatomist trying to create “his anatomy”. The same structure was described in different ways and the name of the author was linked to the name of the structure due to the importance of the fact. The use of the terminology can be international, as it is with Anatomical Terminology (AT).

It can be said that the AT is a specific collection of scientific terms. One of its major flaws was that the body structures were described by varying names, while some of the terms was irrational in nature, and confusing [5]. Anatomic terminology has undergone standardization according to a system known as the Nomina Anatomica (NA). Its golden rules of the system are that there should be one term for each structure and that term selected should have some informative or descriptive value [6].

Anatomy began just as a descriptive science and to each incident was given a morphological idea, and so, the anatomists described the structure they saw by comparing 454

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them to common or familiar objects and that best, in their opinion, reflected that morphology, like escafoides (like a canoe), deltoides (like the Greek capitat letter D), and so on. But this led to the accumulation of 50,000 names by the year 1980 [7,8].

You can imagine a Symposium being held with papers like “The anatomy of pars nasalis of the inverecundum”, “The morphology of the mucosa of the cannus”, “The blood supply of the coles femininus”, “The epithelium of the morsus diaboli”, “The function of the ganglion cerebri anterius”, “The fate of the liquor scarpae”, or “The innervation of musculus deprimens”, and so on. I know that those names are not familiar to most of you but they were largely used many years ago. But now if I used the names os frontale, vagina, clitoris, tuba uterina, corpus striatum, endolympha, and M. rectus inferior everybody would know what I was talking about because I would be using a common language.

How, then, names were formed? In the first place we must remember that Latin was the universal scientific language when Anatomy began as a science. So, it was natural that the names were described in that language even borrowing terms from the early Greek and Arabic masters [7]. Latin is a universal scientific language because it is not used anymore by any country and that is very important [9]. A question arises as to how and when the anatomical terms were invented and developed. The literature tells us that many of the anatomical terms for muscles, vessels and nerves were coined in the 16th and early 17th centuries [2].

The first traces of the nomenclature go back to the time of Hippokrates of Kós (circa 460-370 BC) in Greece; Aristotle (Aristoteles, 284-322 BC); Rufus os Efesos (late 1st century AD); Aulus Cronelius Celsus (25 BC – circa 50 AD); Claudius Galenos of Pergamon (129 or 130-199 or 200); Andreas Vesalius Bruxellensis (Andreas van Wesel, 1514-1564); Jacobus Sylvius (Jacque Dubois, 1478-1555); Gabrielle Fallopio (1523-1563); Bartholomeo Eustachi (1513?-1574); Gaspar (Gaspard) Bauhin (1560-1624); Johannes Jessenius (Ján Jesenský, 1566-1621); and Caspar Bartholin (1655-1738) [3,10].

The spread of science was possible due to the invention of the press with movable letters and the adoption of Latin as a scientific universal language. According to Whitmore [11], Latin as a dead language no longer develops. Its use in terminology can be characterized as global and “nonsecular”, i.e., destined for the whole world and professional layers. Whitmore states that out of the number of advantages classical languages offer, it is constancy, international character, and neutrality – unlike national languages – that ate highlighted. These two facts broke the walls among the ancient masters and made it possible to every student to gain access to the papers formerly well protected and accessible to a few scholars.

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We have to admire the great imagination of the early anatomists when giving a name to a new structure. Today, many names sound ridiculous, but we persist in using them because we are not worried with their meaning; we became indifferent with a false name or false idea. This is disturbing to the beginner when he follows our advice and tries to discover the meaning of every new term.

A few terms of the old languages in spite of its imaginative etymology, are still in use. But this does not invalidate the other 6,000 terms that now make the bulk of our language. We are not only using the common shape but the position and the function of the structure in order to build a better name, names with meaning and soul not only with a body. It seems to me that it would be better for the understanding of the students, health practitioners, and translator for instance, to say vena superficialis lateralis branchii and vena superficialis medialis branchii instead of vena cephalica and vena basilica that are meaningless.

You take for instance the musculus sartorius: it is meaningless; in the first place it should be sartoris and not sartorius because the muscle, as far as I know, does no needle work but it is supposed to be used by the tailors and everybody when crossing the legs when sewing. Why not call it musculus diagonalis femoris since we have a rectus femoris. I think it is a better name and in spite of the large use of sartorius the name should be changed. A very hard work has been done but we still have much to do [12].

We are really indebted to the German anatomists because of their courage and determination in transforming a pile of names in an orderly and understandable language.

The society of German-speaking anatopmists (Anatomische Gesellschaft) issued the first Latin anatomical nomenclature in 1895 as the Basiliensia Nomina Anatomica (BNA) [2,3,9,10]. The list of approximately 4,500 anatomical terms cut through much the redundancy and was quickly accepted in the United States and in many countries in Europe. The BNA was revised in 1933 by British abatomists to include English equivalents for many of the original German terms. In 1955, the International Congress of Anatomists made a few further revisions and the resulting Nomina Anatomica is now accepted as the official source of anatomical terms by the professional medical and anatomical societies of over 30 countries [10].

The eponyms – this is another cause of misinformation among young students because an eponym is meaningless.

The vein of Galen, the ductus of Arantius, the fascia of Cooper, the ligament of Hesselbach, the valvula of Heister, the gland of Cloquet, the bone of Vesalius, the muscle of Klein, the sucking muscle of Krause, the Poupart’s ligament, the Bartholin’s gland and one hundred more names are completely nonsense and means nothing to a student. To maintain those eponyms in order to honor the old master is

an aberration and we fail twice; we do not give the structure an understandable name and we add nothing to the author’s name. I agree that students should have some knowledge of the history of this science and to know a little of the men who have contributed to its progress but this is attained in a course of history of Anatomy and not with eponyms.

Besides that, many eponyms are not right. In many instances the real name of the first author is omitted and the name used is of an author with larger influence in his time. We can note another failure in the eponyms: different structures and shapes with the same name: Eustachium and Fallopian tubes; Alcock, Hunter, Arantii, Fontana and Schlemm canals; gland of Blandin, Nuhn; gland of Bartholin, Duverney, Tiedemann; Bundle of His and Kent’s bundle; Node of Keith-Flack and Koch’s node to only cite some of them [10,13]. It is not difficult to link the name of Paganini to the violin, or Bach to the harpsichord but one cannot find it easy to link the name of Fallopio to a tuba!

To insist on the use of eponyms is an absurd but it is understandable when you do not know and do not want to explain the ethnology of the real term but it is almost a crime because you withhold an important information to the students that will be unable to understand other books with the good terminology and I have seen, as a practicing translator, good new books full of eponyms! How can we expect to see our students learning the anatomical terminology in Latin when we do not use it. I strongly appeal to you all to use the correct Latin terminology in your papers and books and also to use the correct Latin pronunciation like epithelium and not epaitilium, extensor digiti quint: and not digitai qnintai as I have heard many times [12].

Among the nearly 7,000 terms of our actual terminologia Anatomica we still have some terms that should be changed to make our language as perfect as possible and having in mind the didactic importance of the list. The students were perplexed few years ago when they saw in the Terminologia (Nomina) Anatomica three or four aortas (ascendens, descendens, thoracica and abdominalis) and found only one in the cadaver; three nervous systems (central, peripheral and autonomic) and found only one in the dissections. I know that we will meet resistances from many sources. The older teachers do not want to change their minds and to set aside a term they are using for so many years and they will support the errors with fantastic and amazing arguments. It took hundreds of years to change the concepts devised by Galen. But a man can be a sinner for seventy seven years and become saint one minute before his death.

The small success of the anatomical language may be due to the lack of knowledge of Latin, to the lack of uniformity in the numerous textbooks and a poor diffusion of the Terminologia (Nomina) Terminology. But the teachers are responsible for our language and if we do not 455

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believe and do not use it we cannot expect our students to behave differently. If we do not emphasize the use of our language we will come, in few years, to the same position of our colleagues 200 years ago.

There is no consensus regarding the use of official anatomical terms. Usual or nonofficial technical terms which lead to terminology or translation misunderstanding is often a source of confusion to practitioners and translators worldwide. Because anatomical terminology is the foundation of medical terminology and language, it is important that physicians and scientists, as well as all the Allied Health Sciences practitioners throughout the world use the same name for each structure. Physicians must be aware of the new Terminologia Anatomica, which is the joint creation of the Federative Committee on Anatomical Terminology (FCAT). They all must learn the correct nomenclature that enables precise communication among practitioners worldwide, as well as among scholars in basic and applied health sciences [14].

Should eponyms be abandoned? Of course not, once they remain a useful reflection of medical history. We just want to alert the Health and Allied Health Sciences Professional and students that we ‘strongly recommend’ not to use an eponym when it is made at the expense of an anatomical structure [15].

Can you imagine if the musicians did not stick to their norms and notation, to their language? Today it would be impossible to read Bach or Mozart and one musician would be unable to play the music written by another. I agree with my father (Professor Werneck, MD, PhD) when he says that “a better understanding of the language of Anatomy will help in turning its study from a collection of incomprehensible terms and dry facts into an intelligible and interesting science”. We have a language; let us help to improve it; let us believe in it; let us give to it the attention it deserves because in doing so, we are not defending only a language, we are defending our survival as a group, and we will be dignifying the old masters who devoted their lives to the progress of Anatomy.

2. Sakai T. Historical evolution of anatomical terminology from ancient to modern. Anat Sci Int. 2007;82(2):65-81.

REFERENCES 1. Segura J. The Spanish Language in Medicine. Available at: <http://accurapid.com/journal/09medic1.htm> Accessed 11/25/ 2011.

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3. Kachlik D, Bozdechova I, Cech P, Musil V, Baca V. Mistakes in the usage of anatomical terminology in clinical practice.

Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub.

2009;153(2):157-61.

4. Mulligan M. International anatomical terminology. Skeletal Radiol. 2006;35(10):717-8.

5. Gielecki J, Zurada A, Osman N. Terminologia anatomica in the past and the future from perspective of 110th anniversary of Polish Anatomical Terminology. Folia Morphol. 2008;67(2):8797.

6. Catlin B, Lyons J. Etymology. Dartmouth Medical School.

Site editor: Rand Swenson.

7. Field EJ, Harrison RJ. Anatomical terms: their origin and derivation. Cambridge: W. Heffer & Sons; 1957.

8. Cole FJ. A history of comparative anatomy from Aristoteles to the eighteenth century. London: McMillan; 1944.

9. Marecková E, Simon F, Cervený L. Latin as the language of medical terminology: some remarks on its role and prospects.

Swiss Med Wkly. 2002;132(41-42):581-7.

10. Anatomical Terminology: the case against eponyms. Available at: http://www.docstoc.com/docs/41413146/ A N AT O M I C A L - T E R M I N O L O G Y- - T H E - C A S E AGAINST-EPONYMS 11. Whitmore I. Terminologia anatomica: new terminology for the new anatomist. Anat Rec. 1999;257(2):50-3.

12. Werneck H. The language of Anatomy. J Anat Soc India.1985;34(1):1-5.

13. Swee CTE. Eponyms in Medicine. SMA News. 2007;39(8):203.

14. Werneck AL, Batigália F. Common usage of cardiologic anatomical terminology: critical analysis and a trilingual discussion proposal. Rev Bras Cir Cardiovasc. 2009;24(3):28996.

15. Werneck AL, Batigália F. Anatomical eponyms in Cardiology from to the 60s to the XXI century. Rev Bras Cir Cardiovasc.

2011;26(1):98-106.

SPECIAL ARTICLE

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A reflection on the performance of pediatric cardiac surgery in the State of São Paulo Uma reflexão sobre o desempenho da cirurgia cardíaca pediátrica no Estado de São Paulo

Luiz Fernando Caneo1, Marcelo Biscegli Jatene2, Nelson Yatsuda3, Walter J Gomes4

DOI: 10.5935/1678-9741.20120076

Descriptors: Congenital heart disease. Congenital heart defects/surgery. Cardiac surgical procedures.

INTRODUCTION The prevalence of congenital heart disease is 9 children per 1000 births [1] and is estimated to rise to 28,846 new cases of congenital heart disease in Brazil each year.

Around 20% of these cases, the defect resolution is spontaneous, being related to less complex defects and discrete hemodynamic repercussion [2]. Based on these parameters, the average need of cardiovascular surgery in congenital heart disease in Brazil is approximately 23,077 procedures / year, as part of this estimate, besides new births with congenital heart disease, cases of reoperation in patients operated during evolution. In 2002, 8092 patients were operated, which shows a gap of 65%, with

1. Department of Pediatric Cardiovascular Surgery of the Brazilian Society of Cardiovascular Surgery, Physician Assistant, Division of Cardiovascular Surgery, Heart Institute of the Medical School Clinical Hospital, University of São Paulo (INCOR-HCFMUSP), Sao Paulo , SP, Brazil.

2. Department of Pediatric Cardiovascular Surgery of the Brazilian Society of Cardiovascular Surgery, Director of Pediatric Cardiac Surgery Unit INCOR-HCFMUSP, São Paulo, SP, Brazil.

3. Master’s Student of the Professional Master Course in Collective Health, Graduate School of Medical Sciences of Santa Casa de São Paulo, São Paulo, SP, Brazil.

RBCCV 44205-1407

Descritores: Cardiopatias congênitas. Cardiopatias congênitas/ cirurgia. Procedimentos cirúrgicos cardíacos.

the highest rates in the North and Northeast regions of Brazil (93.5% and 77.4%, respectively) and lowest in the South and Midwest regions (46.4% and 57.4%, respectively) [2]. Early treatment of congenital heart disease modifies the natural history, avoiding early death, substantially decreasing hospitalizations caused by complications of the disease, and also providing better quality of life. It is known that 50% of patients with congenital heart disease should be operated in the first year of life. Thus, 11,539 new procedures are necessary every year in Brazil. As the public sector absorbs 86.1% of the cases, it is estimated a deficit of 80.5%. The situation is most critical in the North and Northeast, with a deficit of 97.5% and 92%, respectively [2].

4. President of the Brazilian Society of Cardiovascular Surgery, São Paulo, SP, Brazil.

Correspondence Address: Luiz Fernando Caneo 44 Dr. Eneas de Carvalho Aguiar Avenue, - São Paulo, SP, Brazil – Zip code: 05403-900 E-mail: caneo@mac.com Article received on July 1st, 2012 Approved on July 25th, 2012

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Abbreviations, Acronyms & Symbols ICD DATASUS HDI WHO PAHO GPD RIPSA SEADE SES-SP IMR ICU

International Classification of Diseases Unified Health System Database Human Development Index World Health Organization Pan American Health Organization Gross Domestic Product Interagency Network of Information for Health State System of Data Analysis State of São Paulo Health Departament Infant mortality rate Intensive Care Unit

Brazil is a country of continental dimensions with many regional differences. Establishing objective parameters to evaluate our quantitative and qualitative results that can be compared to those of countries where child care with congenital heart disease has proved more efficient is a big challenge. Considering the state of São Paulo as a reference, we expect to be a country economically and demographically comparable, drawing a parallel, in relation to the quality of care for patients with congenital heart disease requiring surgery.

Recently, publications of the magazine “The Economist”, the Brazilian states were compared to countries as to its individual gross domestic product (GDP) and its GDP per capita. Using these criteria, the state of São Paulo amounted to Poland, in other words, a country with per capita income greater than U.S. $ 12,276, which according to the World Bank is classified as part of the group of countries with high income per capita. São Paulo has always been considered as one of the most developed and prosperous state of the country, and although it occupies the first position in this publication, it is in second place, losing only to the Federal District. While the Federal District has a lower GDP, the GDP per capita is compared to that of Portugal and greater than that of Poland.

When we use other indicators to assess our development, the observed result reinforces our position equal to developed countries. Whereas, for example, the Human Development Index (HDI). Sao Paulo is in third place ranking among Brazilian states, where its index is 0.82, again very close to that of Poland is 0.81. The Federal District is in first place with a score of 0.844, followed by Santa Catarina in second with 0.822. Despite occupying the third position, São Paulo had an increase of only 5.4% of HDI in the 90’s and, therefore, dropped from second to third place.

Some Brazilian states are comparable to many European countries in terms of economic and financial analysis. The State of São Paulo, in turn, can be considered a wealthy state, economically developed and compared to a first world nation. The economic growth of our country has been 458

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widely publicized and celebrated in diverse information sources locally and internationally.

If we are economically occupying a rather optimistic scenario, how are we behaving in the care of children with heart disease? There are countless indicators that we could use in this assessment, but we would like to call attention to the infant mortality rate and its decrease observed in the State of São Paulo, which was published recently by the State System of Data Analysis (SEADE) in its bulletin number 6, in August 2011. The infant mortality rate (IMR which corresponds to the ratio between the numbers of deaths of children younger than one year of age per thousand live births in the population residing in a given geographic area, the current year) expected for a country with income exceeding USD 12.276 is 6 per thousand.

The observed rate in São Paulo in 2010 was 11.9 per thousand, 5% lower than that recorded in 2009 (12.5 deaths per thousand live births). Comparing it with those of later years, it is observed that the IMR decreased by 30% compared to 2000 (17.0 per thousand) and 62% compared to 1990 (31.2 per thousand). Although higher than expected for regions with the same GDP per capita and with the same level of economic development, this result reaffirms the position of São Paulo as one of the states with lower risk of infant death in Brazil in accordance with the Interagency Network Information for Health (RIPSA), formalized by Ministerial Ordinance (Ordinance No. 2.390/GM, Ministry of Health), and participant in term of cooperation with the Pan American Health Organization (PAHO) and World Health Organization (WHO) responsible for standardization and dissemination of official information on health in the country.

If we go deeper into the analysis of these numbers, we can understand the reason for this difference. In a more detailed analysis of these data, we identified that among the causes of infant mortality according to the chapters of causes of death in ICD-10 (WHO, 1998), only two of them perinatal and congenital malformations - are currently responsible for 80% of deaths in Sao Paulo. Perinatal causes, those related to problems in pregnancy, at delivery and at birth, compared to 2000, decreased approximately 30% and were primarily responsible for the decrease in infant mortality in the period (63% of the total reduction).

On the other hand, infant deaths due to congenital malformations presented in the same period were the lowest rates - only 12%. Thus, their share of total infant deaths increased from 17% (2000) to 21% (2010).

Interestingly, congenital cardiovascular malformations are the leading cause of death in this group. Assuming that congenital heart disease can be treated, and it can also be considered a preventable death, the adequate treatment of this population will result in significant reduction in IMR. Thus, the problems of public health in the state of São

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Paulo, as well as the rich and developed countries, are not restricted to basic health and are also problems arising from complex specialties such as cardiology and pediatric cardiac surgery. To exemplify this statement, congenital heart defects are responsible for the decline of 59% of all deaths in the United States in the years 1970 to 1997, with better results in their treatment [3].

When we analyzed the deaths under 1 year of age, according to preliminary data from the Database Health System (DATASUS), there were 7155 deaths in 2010, of this total, 1490 (21% of IMR) were by birth defects as the underlying cause of deaths, congenital heart defects as the most common malformations, occurring as the underlying cause in 607 deaths (40% of malformations). Of the total infant deaths, we observed in 1012 (14.2% of IMR) had an International Classification of Diseases (ICD) of CHD in any line of cause on the death certificate (Part I or II of the causes of death in the death certificate).

The state of São Paulo is recognized as one the major pediatric cardiac surgery centers in the country with 12 services, 6 of them in the city of São Paulo and 6 in the state. In the year 2010, 600 surgeries were performed in the State of Sao Paulo in children under 1 year of age (160 newborns and 440 under 1 year of age), with an average hospital mortality of 14%, neonates (until 28 days of age) presented a rate of 26.8% and 9.32% in children who were 29 days to 1 year old (data from the Ministry of Health of the State of Sao Paulo - SP-SES). The demand for this population is 2,693 surgeries annually.

Whereas about 50% of these children require some type of surgical procedure during the first year of life, the demand is 1,300 procedures in this age group, and at least 80% by the public health system. Whereas the total number of surgeries performed in children younger than 1 year of age in 2010 was 600, our research results show a deficit of 54% in this age group.

Poland has a current population exceeding 38 million, very similar to Sao Paulo. In 2010, Poland presented an IMR of 6.8 per thousand, very close to that expected for their economic condition. As previously noted, the demand for cardiac surgery varies with the number of live births.

Taking into consideration this fact, we can draw a comparison with the state of São Paulo, with regard to the need for pediatric cardiac surgery population and the number of procedures performed. We should use an indicator to assess the number of live births per thousand inhabitants in the population of a given geographic area, in the current year (birth rate).

It was noticeable that Poland had fewer births (birth rate: 9.5 births/1000 inhabitants or fertility rate: 1.23 births/ woman) than the state of São Paulo (birth rate: 13.3 births/ 1000 inhabitants or fertility rate: 1.78 births/woman) in 2010.

Moreover, the absolute number of surgeries in children

aged less than 1 year operated in Poland was superior to that performed in the State of São Paulo (1646 children, 637 infants with neonatal mortality and 1009 newborns with 8.7 and 4.7% respectively) - data from the National Report of Poland, EACTS Congenital Database, and sent by Dr. Tobota and Bohdan Maruszewski in the same period.

Considering birth rates, population need for surgery in the first year of life and number of surgery performed in 2010, Poland performed 100% of its needs, while the state of São Paulo only 50%. Besides the lower number of procedures and insufficient demand by population, surgical outcomes when compared to Poland, regardless of the degree of complexity, but related to the same age group, are inferior to that country (in-hospital mortality observed in the State of Sao Paulo services: 26.68% and 9.3%, 8.7% and 4.7% in Poland for neonates and infants, respectively).

In attempting to explain this scenario, the first impression is that lack of access in our state, and perhaps increase the number of centers would be a solution that will quickly come up. The solution, however, does not seem to be an increase in the number of centers and, even those that already exist need to produce what is expected of them.

When they reach their limit, we can consider increasing the number of centers. This can be seen when analyzing the production of state services (SES-SP report), many of them do not achieve the minimum number specified by ordinance 210 which directs its accreditation. As for the results, recent studies show that they depend on many factors, not only technical, but also the number of surgeries performed at the center, organizational structure and technology among others. Pediatric cardiac surgery has much in common with high-tech systems, where performance and results depend on individual, technical and organizational factors, and their interactions. Further analysis should be performed to understand this scenario, since they are multivariate factors.

Considering the importance of congenital heart disease in the composition of IMR in richer countries, improving care in this specialty will cause a major impact in reducing it. So that we can achieve the IMR indexes in Sao Paulo equivalent to indexes in Poland, and the so-called developed countries, it is essential, in addition to improving prenatal diagnosis and delivery care, increasing the number of surgical procedures in congenital heart disease and improving the current immediate results.

Ensuring children’s access to cardiac care network specialist and improvement of surgical outcomes of specialized services are fundamental in order to have a significant decrease in infant mortality in the State of São Paulo. In states as ours, the proper treatment of congenital heart disease, ensuring access to those that need it, encouraging centers qualified for this assistance, ongoing training of the staff involved and adequate investment have become an important public health problem.

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Although expensive, highly specialized and complex, the development of a well-structured pediatric cardiac surgery today occupies an important role in public health policy, particularly in states that have reached a high degree of economic development. The difficulty of access is just one of the problems generated by poverty and inequality where pediatric cardiac surgery is not considered a priority and it cannot be done if there is lack of money or infrastructure [4]. If some states require larger number of centers, others will benefit from improvements in existing centers.

Anyway, the child care network of cardiac patient needs to be rethought and restructured in order of priority. There is no doubt that the lack of adequate funding, lack of specialized centers in certain regions, lack of trained personnel and a continuing education and the organization of the network play a key role in this scenario. With regard to the funding, we believe that it is not a simple increase in their values that count, but the form of management. We recently observed that while more money has been allocated to pediatric cardiac surgery in recent years, had little impact on increasing the number of surgeries.

Using Poland as an example, how to explain that the per capita health expenditure in Poland, similar to the State of São Paulo (6.12% versus 5.94% of GDP in USD - 1997, World Bank 2002), has best results (number of surgeries by population demand, immediate surgical results, among other indicators analyzed). The money allocated by the federal government does not always get to the pediatric cardiac surgery service the way it should. There are numerous reasons, but perhaps the most important one is that there is no discrimination of cardiovascular pediatric surgery from cardiovascular surgery in general in hiring service between the provider and the local government.

Few centers have a specific contract for pediatric cardiac surgery, which makes the financial ceiling be allocated according to institutional and personal interest in cardiac surgery in general, including pacemaker and hemodynamics. Often, the budget of pediatric cardiac surgery procedures is intended for less complex, lower cost or higher institutional or personal interests. The remuneration differentiated according to the complexity of the procedure appears to be yet another major problem, especially for those that face the more complex cases.

The fact that almost no differentiation is made in the payment procedure according to its complexity punishes the referral center that is dedicated to more complex cases and discourages the growth of the number of procedures in neonates and infants, especially in the higher complexity scores. Some international studies have shown that there is a linear relationship between the complexity and the procedure costs [5]. This was also observed in our environment [6], where the group using the procedures by

means of classification by Aristotle Basic Score [7] observed that patients with higher rating than twice the required length of stay in Intensive care unit (ICU). These same patients had higher number of examinations, diagnostic tests and procedures. The presence of infection before the procedure, regardless of age group and complexity, triples the procedures costs. Postoperative infection increases at three times the cost of surgery in neonates and adolescents and doubles the cost in more complex patients. If everything does not improve, probably the high complexity will be penalized by the inefficiency of the system.

Low pay, high cost and high complexity make few centers perform over 250 cases per year in Brazil, which is considered an ideal number to obtain adequate results in congenital heart surgery, in order to have good surgical results and low mortality [8]. Few pediatric cardiac surgery centers are located in children’s hospitals, and the number of personnel trained in this area of knowledge is very small.

In an interview conducted among Brazilian pediatric surgeons [9], only 29% of surgeons who were considered pediatric surgeons (since there is no such area of interest in the Brazilian cardiovascular surgery) stated that they are qualified to perform any type of procedure, regardless of the child’s age.

Although the accuracy and technical quality of surgery have a role in postoperative survival of newborns and infants, they add up to the early diagnosis, surgical center volume, presence of very well trained interdisciplinary skilled labor, advanced technology and adequate infrastructure to the complexity. Leadership, technical skills and techniques are also not necessary to solve these problems - a puzzle of many challenges - especially in neonatal surgery, which, despite some exceptions, remains a major problem in most developing countries. Complexity requires complexity: less and less in relation to neonatal surgery! [10].

The individual contribution of Brazilian surgeons in pediatric cardiac surgery is quite remarkable, since the Jatene Operation for transposition of the great arteries and also the Cone Operation, for the correction of tricuspid regurgitation in Ebstein‘s disease. It is undisputed the technical quality of our surgeons. However, as seen previously in a complex system, individual technical skills alone are not responsible for the outcome. The results of surgery depend on high complexity of the entire hospital system and its interaction with the technically and nontechnically human capital (cognitive and noncognitive).

Changing our current system, centered on the individual ability of the person to an interdependent and interdisciplinary health system, with well-established policies, centered on quality, patient safety and sustainability must be our goal. To do so, establishing fair and adequate funding, education and training, continuous

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monitoring and objective results with the active participation with the government agencies is fundamental.

After comparing Sao Paulo with Poland, we noted that despite the being equal in some aspects, we also have differences, and there is no doubt that, if we identify those differences, we can achieve excellence in pediatric cardiac surgery in this country of inequalities. Finding what is common in our problems and concentrate on solving them can be the best solution (“We all do better when we work together. Our differences matter, but our common humanity matters more.” President Clinton.)

Today, congenital heart disease already occupies a large role in public health in some Brazilian states, and will certainly occupy in the near future an important role in other areas. If we solve some common ground, surely we will be preparing for all our problems to be are solved in a gradual escalation of priorities.

data, benchmark, set quality standards, either through the creation of specific database and / or use existing database.

“The most important thing I’ve learned in government is that you cannot propose that anything will work in Brazil as a whole.”

Vilmar Faria Among the various actions required at this moment, we chose some important and common ones in our diversity: • Improve access to pediatric cardiac surgery centers: o to improve children’s access to cardiac centers; o Extend the productive capacity and qualify of existing centers; o Open new centers in underserved regions; o Plan and execute the policies related to cardiology and pediatric cardiac surgery in an organized way, with the support of well-established centers, respecting geographical distances, with the active participation of society with government agencies, through its technical councils and also taking into account regional needs; o Implement policies that increase the capacity of the health system in diagnosing congenital heart defects, especially during ante-natal period.

• Improve the financing of Cardiology and Pediatric Cardiac Surgery o Find a new way to secure funding for pediatric cardiac surgery through a review of existing contracts, forms of transfer and adequate compensation, respecting the complexity. The essence of this proposal is that if they get the budget for pediatric heart surgery is effectively applied to it and to its dedicated service.

• Improve database and promote quality management by: o

Create the culture of management by objective

• Establish continuing education programs: o Establish training programs in different health care professions involved with the care of children with heart disease. Establish training centers along with the other scientific bodies, both in the curriculum discussion and also in mainstream education and training of specialized teams.

Along with the increase observed in our current economic environment, the complexity of our specialty, if well balanced, should put us back in a prominent position on the stage of cardiology and pediatric cardiac surgery worldwide.

From a regional perspective, the services of pediatric cardiac surgery in São Paulo have been meeting on a regular basis, along with the state government, through representatives of SES-SP to discuss, plan and implement actions to improve the network of cardiac care to children in this region. Recently, constituted by a Technical Board, as provided by ordinance MS 210 [11,12], where representatives of the Department of Pediatric Cardiovascular of the Brazilian Society of Pediatrics and the Brazilian Society of Cardiology, the State Department and the Local Department of Health promote discussions based on objective data validated by executors services, solutions to problems raised by managers and difficulties pointed out by the Services.

All this effort, although recent, makes us aware of the strengths, weaknesses, opportunities and threats to all members of the complex network of public health, by a consensus and collective form. Hopefully, in the coming years, our service network, today pointed to the disability and known by all of us, can be compared to those countries that occupy a prominent position on the world stage.

Likewise, we hope that the experience of our State will contribute with other Brazilian states, in the sense that solutions to complex problems depends on the joint efforts of all sides of the issue.

Promoting improvements in public health care to children with heart disease is not an isolated problem of the government, and perhaps we should close to this issue, along with society in general, to reach and an improvement in our system.

Thanks The authors would like to thank Dr. Bohdan Maruszewski and Dr. Zdzislaw Tobota, responsible for EACTS Congenital Database, the data and information related to Pediatric Cardiac Surgery in Poland and Dr. Rodolfo A. Neirotti and Dr. Fabio B. Jatene, by reviewing and commenting on the text. They would also like to 461

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emphasize the unconditional effort the Sao Paulo State Department of Health, along with representatives of heart surgery services in the State of São Paulo are making, in order to find the solutions necessary to modify the current scenario here pointed.

surgery at the Heart of the Clinics Hospital/São Paulo Medical School, InCor-HC-FMUSP: HTAi 2010. Disponível em: http:/ /www.htai2011.org/Sessoes_Orais2.asp Acesso em: 15/6/2012 In: 8th Annual Meeting HTAi; Rio de Janeiro, 2011.

REFERENCES 1. Pinto Jr VC, Daher CV, Sallum FS, Jatene MB, Croti UA. Situação das cirurgias cardíacas congênitas no Brasil. Rev Bras Cir Cardiovasc. 2004;19(2):III-VI. 2. Pinto Jr VC, Rodrigues LC, Muniz CR. Reflexões sobre a formulação de política de atenção cardiovascular pediátrica no Brasil. Rev Bras Cir Cardiovasc. 2009;24(1):73-80.

3. Lee K, Khoshnood B, Chen L, Wall SN, Cromie WJ, Mittendorf RL. Infant mortality from congenital malformations in the United States, 1970–1997. Obstet Gynecol.

2001;98(4):620-7.

4. Neirotti, R. Paediatric cardiac surgery in less privileged parts of the world. Cardiol Young. 2004;14(3):341-6.

5. Sinzobahamvya N, Kopp T, Photiadis J, Arenz C, Schindler E, Haun C, et al. Surgical management of congenital heart disease: correlation between hospital costs and the Aristotle complexity score. Thorac Cardiovasc Surg. 2010;58(6):322-7.

6. Trindade E, Jatene M, Caneo LF, Tanamati C, Riso AA, Abuchaim D, et al. Five-years follow-up of congenital heart

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7. Lacour-Gayet F, Clarke D, Jacobs J, Gaynor W, Hamilton L, Jacobs M, et al; Aristotle Committee. The Aristotle score for congenital heart surgery. Semin Thorac Cardiovasc Surg Pediatr Card Surg Annu. 2004;7:185-91.

8. Daenen W, Lacour-Gayet F, Aberg T, Comas JV, Daebritz SH, Di Donato R, et al; EACTS Congenital Heart Disease Committee. Optimal structure of a congenital heart surgery department in Europe. Eur J Cardiothorac Surg.

2003;24(3):343-51.

9. Pinto Jr VC. Avaliação da política nacional de atenção cardiovascular de alta complexidade com foco na cirurgia cardiovascular pediátrica [dissertação de mestrado]. Fortaleza: Universidade Federal do Ceará; 2010.

10. Neirotti R. Access to cardiac surgery in the developing world: social, political and economic considerations – FAC – Federación Argentina de Cardiologia – In: 5th Congress of Cardiology on the Internet – 5th Virtual Congress of Cardiology – QVCC – Argentina; 2007.

11. Portaria nº 1169/GM em 15 de junho de 2004. Institui a Política Nacional de Atenção Cardiovascular de Alta Complexidade, e dá outras providências. Diário Oficial, seção 1, n. 115, p.57, 2004.

12. Portaria no 210 SAS/MS de 15 de junho de 2004. Serviços de cirurgia cardiovascular pediátrica. Diário Oficial, seção 1, n.

117, p.43. 2004.

SPECIAL ARTICLE

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Analysis of ordinances regulating the national policy of high complexity cardiovascular care Análise das portarias que regulamentam a Política Nacional de Atenção Cardiovascular de Alta Complexidade

Valdester Cavalcante Pinto Júnior1, Maria Nazaré de Oliveira Fraga2, Sílvia Maria de Freitas3

DOI: 10.5935/1678-9741.20120077

RBCCV 44205-1408

Descriptors: Heart/surgery. Cardiac surgical procedures.

Child care. Health policy. Public Health.

Descritores: Coração/cirurgia. Procedimentos cirúrgicos cardíacos. Cuidado da criança. Política de saúde. Saúde pública.

Ministerial decrees are tools used to create, adapt or regulatory policies established from social demands. The ordinances, subject of this study, inaugurate another moment of care to patients with cardiovascular disease and all forms to the. National Policy of High-complexity Cardiovascular Care The study that follows is a chapter of dissertation: Evaluation of the National Policy of High-complexity Cardiovascular Care focusing on Pediatric Cardiovascular

Surgery, held at the Federal University of Ceará in the Professional Master’s Degree Course in Public Policy Evaluation.

We try to analyze the concepts on which the ordinance is based, according to the principles of the Unified Health System (SUS), literature theorizes that such principles, discourses of managers and directors of companies involved in the merits and results of questionnaire applied to cardiovascular surgeons belonging to the Brazilian

1. Cardiovascular Surgery Specialist, Master in Public Policy Evaluation-UFC, Chief of Pediatric Cardiovascular Surgery, Hospital Dr. Carlos Alberto Studart Gomes/SESA, Incor Criança, Fortaleza, CE, Brazil.

2. PhD, Professor of the Master in Public Policy Evaluation - Federal University of Ceará, Fortaleza, CE, Brazil.

3. Professor of the Master in Public Policy Evaluation - Federal University of Ceará, Fortaleza, CE, Brazil.

Correspondence Address: Valdester Cavalcante Pinto Júnior Avenida Litorânea, 2040 – Lt A3/12 – Fortaleza, CE Brazil - Zip code: 60835-175 E-mail: contatoicca@yahoo.com.br

Work performed at the Federal University of Ceará, Fortaleza, CE, Brazil.

Article accepted on April 7th, 2012 Article approved on September 26th, 2012

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Abbreviations, acronyms and symbols AHA CNRAC DAE/MS DCCVPed MS SOP OPM SAS SBCCV SUS

authorization for hospital admission High Complexity National Regulatory Central High Complexity Department of Specialized Care/ Ministry of Health Pediatric Cardiovascular Surgery Dept.

Ministry of Health Standard Operating Procedure Orthoses, prostheses and materials Department of Health Care Brazilian Society of Cardiovascular Surgery Unified Health System

Society of Cardiovascular Surgery (SBCCV), the sample is calculated by reference to 778 professionals, number provided by SBCCV being distributed in April 2009, as follows: 30 (4%) in the North, 107 (14%) in the Northeast, 68 (9%) in the Midwest region, 437 (56%) and 136 in the Southeast (17%) in the South The sample size for a sampling error of e = 4.87%, was 266 surgeons. Based on this calculation, the sample by region corresponded to ten surgeons in the North, 58 in the Northeast, 25 in the Midwest, Southeast and 43 130 of the South, a total of 266 cardiovascular surgeons.

In January 2003, the Ministry of Health (MS) initiated discussion about comprehensive reform to meet the high complexity and promoted intensive discussion to formulate the so-called: National Policy of High-complexity Cardiovascular Care.

The various specialties were represented by their respective companies, as the Brazilian Society of Cardiology, Brazilian Society of Interventional Radiology and Vascular Surgery, Brazilian Society of Interventional Cardiology, Brazilian Society of Angiology and Vascular Surgery, Brazilian Society of Cardiac Arrhythmias and BSCVS, with its Departments of Cardiac Pacing and Department of Pediatric Cardiovascular Surgery (DCCVPed).

In this scenario, disputes could be observed by medical locus of activity, performance space for hospitals and incorporation of products [1]. The MS proposed to centralize network of university hospitals in the care of high cost and decrease the number of hospitals to the private network, signaling for the development of an exclusionary policy, keeping in view the various requirements for hospitals regarding the physical structure, equipment and human resources, without adequate financial compensation [1].

The SBCCV, during this process, signaled the development of a policy that would meet the regional 464

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differences and the fact that it was impossible to meet all the requirements proposed by MS, since most services registered in cardiovascular surgery was experiencing serious financial difficulties [1].

The legal framework came on June 15, 2004 through two devices: the decree No. 1169/GM [2], which established the National Policy of High-complexity Cardiovascular Care, and Ordinance No. 210 SAS / MS [3] regulated the pediatric cardiovascular surgery. This ordinance was amended in some parameters on May 26, 2006, with the publication of the ordinance SAS / MS No 384.

The decree No. 1169/GM/2004 instituted the National Policy of High-complexity Cardiovascular Care considering some requirements, listed below, who gave props to the conceptual elaboration of Ordinance No. 210 and its annexes, which are discussed below.

1. Comprehensive care to patients with cardiovascular pathologies of the Unified Health System - SUS. Integral care consists of the necessary support to those that need treatment. This concept is of great importance, given that comprehensiveness is one of the principles of the SUS. Integrality is used on an ongoing basis with reference to the guideline of integrated care as the principle of equality of care, seen as a set of actions and, preventive and curative, individual and collective health services at different levels of system complexity [4].

2. Need to organize assistance to those patients on hierarchical and regional services, and based on the principles of universality and integrality of health.

Universality is defined as access by all to all services.

Integrality is the care that comprises all levels of health care, i.e., the provision of assistance.

However, the ordinance of 2004 did not define how the relationship would take the three levels of care with respect to cardiology and pediatric cardiovascular surgery. In order to the principles of universality and integrality to be effective, it would be necessary to structure the specific model of care for pregnant women and the newborn as well as pediatric monitoring, i.e., the creation of a multidisciplinary care team for the primary and secondary care levels as well as capacitating institutions that provide this kind of assistance with necessary equipment for the diagnosis and monitoring of patients. It was also not established how much and from what sources would be the resources to redress these investments, in addition to determining that all units shall participate in the cardiovascular surgery program, as described in paragraph 1.4 of Annex I. As for regionalization, Annex IV of Ordinance # 210 established some parameters of territorial operation. In the case of High Complexity Care Units in Pediatric Cardiovascular Surgery, there shall be a ratio of one unit to

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serve 800,000 inhabitants (1:800.000), which were also adopted by defining the criteria of article eight of the same ordinance.

In defining the quantitative and geographic distribution of units, such as: population to be served; need for health care coverage, access mechanisms with reference and counter reference, technical and operational services; series of visits, taking into account the pent-up demand; integration with the hospital reference network of emergency care and emergency services with prehospital care, with the High Complexity National Regulatory Central (CNRAC) and other outpatient and hospital care services available in the State. In the same article it was decided that, in the absence of any institution to perform highly complex cardiovascular procedures, the local manager should ensure their achievement by directing the patient through CNRAC. Thus, these mechanisms would be rational allocation of resources, organized on the basis of technological hierarchy disposition, seeking to expand the capacity of assistance at the entrance of the system, so that other technologies were incorporated to support the needs of each user considering economies of scale and scope. However, it is observed that it is still needed due geographical distribution of health services, human resources and programs, enabling the connection of multiple clinical knowledge and collective health to provide comprehensive care with strategies and mechanisms of articulation and appropriate referencing, sufficient to meet the health needs of specific population base [5].

The structuring of a network of regionalized health care has as its objectives the provision of continuous, integral, quality, responsible and humane health care, articulated according to the complementarity of various densities and technology organized by criteria of microeconomic efficiency in use of resources. This kind of network should be made by the planning, management and financing intergovernmental cooperative and focused on the development of integrated health policy tailored to the population needs of each singular regional space [5].

In complement to what has been defined by MS, Artmann & Rivera [6] i it understood that regionalization requires the allocation of health resources in a given area, in order to facilitate access, offer high quality services, low cost and with better fairness and faster responses to the desires and needs of consumers. The regionalization approach is proposed to find the balance between excessive centralization and complete decentralization of structural health services.

The distance is one of the most important elements to establish the geographical distribution of health institutions within the regionalized system. One cannot help commenting that in a country with vast distances,

huge regional differences, especially between the extremes almost depopulated regions and urban centers with overpopulation, we need to think creatively and contextualize parameters through adaptations that bring viable and positive impacts on the problematic situation.

The major criterion for the case is access to treatment [6].

In the case of health care, regionalization meets the criterion of priority planning service provision and the need to rationalize the relationship of these dynamics, establishing greater coordination to achieve results in terms of access and equity adequate [6].

Regionalization of care in pediatric cardiology or collaboration among regional centers can not only improve results by focusing the expertise of qualified staff in some institutions, but also to help evaluate the quality due to the increased number of patients [7].

Related to this proposal, interviewed cardiovascular surgeons indicated the establishment of care centers for care of heart disease of higher complexity. Such centers should be distributed in various regions responsible for territorial base previously established, providing quick and skilled care, as in some diseases the delay in care can be the difference in treatment outcome and other long-term survival in patients .

The ordinance in question has adopted the principle of universality, which is access, indiscriminately, of all to all services, based on regional and hierarchical attention.

However, the current policy lacks an approach that aims to meet the inequities in cardiovascular care, especially in some regions. Speaking universality it is not the same thing as promoting equity. According to Bottle & Porto [8], â&#x20AC;&#x153;equality is a consequence of the equity. The recognition of differences and suppression of needs make possible the achievement of equality.â&#x20AC;?

Equity has been interpreted both in official discourse and in the speech of relevance social agents in the arena of health, as a principle of SUS. It is fair that this is so because the universal systems shall seek fairness [9].

According to Neves [10], equity is equal access to health care through its differentiated redistribution: giving more to those who have less and who even have the same conditions, in a regulatory action of inequalities. This is possible only by the principle of solidarity, in which all men redistribute goods among themselves. It suggests the application of two criteria in particular: the medical need, as a factor of rationalization and equal opportunities, as a factor of universal accessibility.

The Standard Operating Procedure (SOP) 96 aimed to promote equity with quality and rationality in spending. In order to avoid cumulative process unfairly by some municipalities, with the increasing dispossession of others, the composition of municipal systems and ratification of agreed schedules in their health councils aimed to 465

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establishments of regional networks for increased access to quality and lower cost [11].

Annex II of Ordinance No. 210 was based on the principle of integral proposed in Ordinance No. 1169/GM, dealing with classification standards and accreditation of units in highly complex cardiovascular care. It was then determined that such units shall offer comprehensive and specialized assistance to patients with diseases of the cardiovascular system and, therefore, it was necessary to: adhere to the criteria of the National Humanization Policy; develop or participate in prevention programs and early disease detection system cardiovascular; offer diagnosis and treatment for the care of patients with disease of the cardiovascular system; develop rehabilitation programs, support and monitoring through specific procedures that promote the improvement of physical and psychological conditions of the patient, besides acting in the preoperative preparation operative or postoperative in addition towards the restoration of functional capacity.

In general, the policy met the principle of completeness when encompassed in care: early diagnosis, treatment, prevention and rehabilitation.

Pauli [12] divides the levels of primary prevention, which is subdivided into health promotion and specific protection; minor in diagnosis with early treatment and limitation of disability, and tertiary prevention to rehabilitation.

In none of these directives that comprise the National policy there is reference to the type of action or what kind of disease the primary prevention shall be developed. The determinations merely stipulate that such activities shall be developed in coordination with programs and standards defined by various levels of management.

When it comes to early diagnosis, the policy does not establish standards for adequacy of services to the attention of the segment, which begins in the care of the fetus, neonate and child. On the other hand, it would require physical structure, equipment and specialized professionals in order to such to be met.

The sources of funds for the execution of several actions also represent important gap in politics. It is worth mentioning that early diagnosis points to the scheduled time and treatment in the second article of the decree No. 1169/GM determined that the Secretaries of State for Health establish regional planning and hierarchical network to form the State and / or Regional High-complexity Cardiovascular Care, in order to assist patients with diseases of the cardiovascular system that needed to be subjected to procedures classified as high complexity.

As for rehabilitation, tertiary prevention and other actions to promote integrity, the ordinances do not specify the source of payment, making it infeasible adoption by providers, although these have been signed at the time of accreditation.

3. Ensuring these patients to assistance at various levels of complexity, through multidisciplinary teams, using techniques and specific therapeutic methods.

This topic refers to the completeness, and its effectiveness hindered by a lack of coordination between actions at different levels, the lack of infrastructure of services provided to primary and secondary care and tertiary care deficient capacity to meet demand at that level. It is necessary to emphasize that the principle of intersectoriality shall be noted, referring to food conditions, education and leisure, pillars to ensure good cardiovascular health.

4. Need for a new conformation of State Networks and/ or Regional Networks of High-complexity Cardiovascular Care, as well as to determine their role in health care and the technical qualities necessary for the proper performance of their duties.

In order to meet this determination, the second article of the decree No. 210 ordered the secretaries of Health establish regional planning to form a hierarchical Network State and / or Regional Networks of High-complexity Cardiovascular Care. The single paragraph defined the Networks of High-complexity Cardiovascular Care shall be composed of high-complexity cardiovascular care units and referral centers for high cardiovascular complexity. In turn, the high cardiovascular complexity care and referral centers in high cardiovascular complexity conditions shall provide technical, physical facilities, equipment and human resources to provide specialized assistance, develop strong coordination and integration with the local system and regional health care and meet the criteria of the National Humanization Policy. The skills and responsibilities of the departments located in assistance units and referral centers for high cardiovascular complexity care shall be regulated by the Department of Health Care by a specific rule. The minimum parameters of operation of these units were defined in Annex I of Ordinance No. 210.

The same decree No. 210, in the first article of the second paragraph, defined as the Reference Center for Highcomplexity Cardiovascular Care a High-complexity Cardiovascular Care Unit exercising the auxiliary role of a technical nature, the manager in the policies of care in cardiovascular diseases, must possess attributes such as: be a teaching hospital, certified by the Ministry of Education and MS. According to the Interministerial ordinance No. 1000 of the Ministry of Education, April 2004, to be a teaching hospital, this should have a territorial base of operations defined, with a maximum of a referral center for every four million inhabitants; participate articulated and integrated with the system local and regional have structure of organized research and teaching, and programs with established protocols, have adequate management structure capable of ensuring the efficiency, efficacy and

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effectiveness of actions provided; support the activities of managers in regulation, monitoring, control and evaluation, including quality studies and studies of cost-effectiveness; participate as polo professional development in partnership with the manager, based on the Politics of Permanent Education for SUS, MS, and offers at least four services defined in the fifth article of this ordinance.

Importantly, the requirement for territorial basis of performance (maximum a referral center for every four million inhabitants) was revoked in May 2006 by the third article of the decree No. 384. Already the second article, the first paragraph of this Ordinance provided that, in states with population less than 4,000,000 inhabitants, there should be no more than a reference center, since the unit would meet the requirements. The second paragraph of the same article that preferably should be defined as referral centers enabled public hospitals, private philanthropic and private financial gain, in that order, that would fit in the first article, second paragraph, item I. Interviewed cardiovascular surgeons of BSCVS considered the technical criteria contained in the annex to the decree No. 210 as not mutually exclusive and that could serve as a bargaining tool for improvement of some institutions. Others considered as a limiting factor in enrollment, especially in the aspects concerning the formation of multidisciplinary teams, the physical structure and the acquisition of costly equipment.

It is understood that the criteria as parameters are needed to provide adequate service to the segment of cardiac patients. However, based on the fact that the target set in the policy was 239 centers and only 66 were actually enabled, this indicates that the policy was limiting access to the institutions.

5. Update the accreditation system and adapt it to provide procedures for High Complexity, High Technology and High Cost.

Article 11 of Decree No 210 incorporated six annexes: Classification Standards and Accreditation of Highcomplexity Cardiovascular Care Units, Survey Manager Form, MS Survey Form, List of Procedures Included in Tables SIA and SIH / SUS for Cardiovascular Care, Distribution Parameters for Population Assistance Services and Reference Centers for High Cardiovascular Complexity, List of Procedures Excluded from SIA and SIH / SUS Tables. It was created, also, the Table of Compatibility between procedure performed and orthotics, prosthetics and special materials (OPM) and the Cardiovascular Care Procedure Organization.

In the questionnaire applied to cardiovascular surgeons of BSCVS 88.3% of the respondents opined by the need to implement a National Database. They considered that to achieve this it would be necessary to match diagnosis tables, procedures and OPM, using an internationally accepted nomenclature, since the specialty is of high

complexity and thus it is essential to be included in the international context.

6. Improving the system of information concerning the Cardiovascular Care.

The sixth article established a deadline of 120 days to deploy management tools, such as the â&#x20AC;&#x153;Brazilian Registry of Cardiovascular Surgery,â&#x20AC;? but until the completion of this survey, in December 2011, it had not occurred.

The arguments mentioned in the interviews of directors of companies as well as the managers of MS, in explanation for the non-implementation of the record were: lack of political will, the inability to formulate DATASUS the database and lack of interest by having doubts SBCCV about how the data will be used. In this regard were clearly identified divergent interests, mainly related to power management to the database can generate. Most cardiovascular surgeons surveyed (91.4%) believes that the database should be managed by the department (DCCVPed) or by BSCVS, while 76.6% believe that the filling should be mandatory and linked to the authorization for hospital admission (AHA) and 93.1% participate in the record even if not compulsory to fill.

Establish mechanisms for the regulation, supervision, control and evaluation of the care provided to these patients.

These mechanisms were effective, in part, by registering cardiovascular surgery. That record, in turn, should equip the actions specified in Annex I of Ordinance No. 210, topic 1.7. Under Annex, maintenance of accreditation services would be conditional: the continued fulfillment of the standards established in the ordinance for unity; evaluation to be performed by periodic audits or recommended by the Department of Health Care (SAS), run by the Department of Health under whose management is unity, and the reports generated should then be forwarded to the General Coordination for High Complexity Department of Specialized Care (DAE / MS) for analysis that would determine the continuation or suspension of accreditation, based on compliance or not the standards established by ordinance, regular reports on the evaluation and annual production. According to the surgeons interviewed, the record could be powered by untrusted data, since they would have among their purposes to support maintenance or suspension of accreditation.

Unfortunately, it remains a challenge to be faced in the fight for effective implementation of policies, in which universal access to effective and resolution should be a guarantee. Overcoming the gap between rule and practice is the way to go for multithreaded interested in solving the ills of this population as specific, as is the scope of notorious intentions contained in ordinances.

The universality, comprehensiveness and equity of health care shall be the goal of health policies that propose to be inducing quality healthcare.

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REFERENCES 1. Pinto Júnior VC, Rodrigues LC, Muniz CR. Reflexões sobre a formulação de política de atenção cardiovascular pediátrica no Brasil. Rev Bras Cir Cardiovasc. 2009;24(1):73-80.

2. Brasil. Portaria no 1169/GM em 15 de junho de 2004. Institui a Política Nacional de Atenção Cardiovascular de Alta Complexidade, e dá outras providências. Diário Oficial 2004; seção 1, n.115, p.57.

3. Brasil. Portaria 210 SAS/MS de 15 de junho de 2004. Serviços de cirurgia cardiovascular pediátrica. Diário Oficial 2004; seção 1, n.117, p.43.

4. Silva JPV, Pinheiro R, Machado FRS. Necessidades, demanda e oferta: algumas contribuições sobre os sentidos, significados e valores na construção da integralidade na reforma do Setor Saúde. Saúde Debate. 2003;27(65):234-42.

5. Brasil. Ministério da Saúde. Secretaria de Atenção à SaúdeSAS. Redes Regionalizadas de Atenção à Saúde: Contexto, premissas, diretrizes gerais, agenda tripartite para discussão e proposta de metodologia para apoio à implementação. Brasília: Ministério da Saúde;2008.

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6. Artmann E, Rivera FJU. Regionalização em saúde e mix públicoprivado. 2003. Disponível em: http://www.ans.gov.br/data/files Acesso em: 21 mai. 2009.

7. Chang RR, Klitzner TS. Can regionalization decrease the number of deaths for children who undergo cardiac surgery? A theoretical analysis. Pediatr. 2002;109(2):173-81.

8. Garrafa V, Porto D. Bioética, poder e injustiça: por uma ética de intervenção. Mundo Saúde. 1995;26(1):6-15.

9. Brasil. Conselho Nacional de Secretário de Saúde. Coleção Progestores para entender o SUS. Brasília:CONASS;2007.

10. Neves MCP. Alocação de recursos em saúde: considerações éticas. Bioética. 1999;7(2):155-63.

11. Duarte CMR. Equidade na legislação: um princípio do sistema de saúde brasileiro. Ciênc Saúde Coletiva.

2000;5(2):443-63.

12. Pauli LTS. A Integralidade das ações em saúde e a intersetorialidade municipal [Dissertação de mestrado]. São Paulo: Faculdade de Saúde Pública, Universidade de São Paulo; 2007.

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Pioneering transcatheter aortic valve Implant (Inovare®) via transfemoral Implante pioneiro de valva aórtica transcateter (Inovare®) por via transfemoral

José Carlos Dorsa Vieira Pontes1, João Jackson Duarte2, Augusto Daige da Silva3, Amaury Mont’Serrat Ávila Souza Dias2, Ricardo Adala Benfatti2, Neimar Gardenal2, Amanda Ferreira Carli Benfatti4, Jandir Ferreira Gomes Jr.2

DOI: 10.5935/1678-9741.20120078

RBCCV 44205-1409

Abstract We present a patient with severe aortic valvular bioprosthesis dysfunction implanted for 11 years, presenting with acute pulmonary edema due to severe valvular insufficiency with severe systolic dysfunction (EF <30%) and comorbid conditions that amounted operative risk (STS score > 10). We carried out the transcatheter aortic valve implantation (Inovare® - Braile Biomedica), which was implemented successfully by transfemoral access and good patient outcomes.

Resumo Apresentamos o caso de paciente com disfunção de bioprótese valvar aórtica implantada há 11 anos, apresentando quadro de edema agudo pulmonar em decorrência de insuficiência valvar grave. Apresentava disfunção sistólica grave (FE< 30%) e comorbidades que elevavam seu risco operatório (STS score > 10). Realizou-se o implante de valva aórtica transcateter Inovare® - Braile Biomédica, por acesso transfemoral. O implante foi realizado com sucesso e o paciente apresentou boa evolução.

Descriptors: Heart valve prosthesis. Aortic valve/surgery.

Heart valve prosthesis implantation. Aortic valve insufficiency.

Descritores: Próteses valvulares cardíacas. Valva aórtica / cirurgia. Implante de prótese de valva cardíaca. Insuficiência da valva aórtica.

1 – PhD; General Director of the University Hospital - UFMS; Cardiovascular Surgeon.

2 – Cardiovascular Surgeon; University Hospital - UFMS. 3 – Intervencionist Cardiologist; University Hospital - UFMS. 4 - Cardiologist; University Hospital – UFMS.

Correspondence address: José Carlos Dorsa Vieira Pontes Rua Filinto Muller, 355 – Campo Grande, MS, Brazil – Zip code: 79080-190 E-mail: carlosdorsa@uol.com.br

This study was carried out at University Hospital of Federal University of Mato Grosso do Sul, Campo Grande, MS, Brazil.

Article received on May 26th, 2012 Article accepted on September 5th, 2012

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Abbreviations, acronyms & symbols TAVI

transcatheter aortic valve implantation

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to ensure the exact position of the prosthesis release and prove the effectiveness of the procedure when comparing the preoperative and postoperative images.

After the procedure the patient was transferred to the coronary care unit, where he remained hospitalized for 2 days and discharged after three days of hospitalization.

INTRODUCTION The transcatheter aortic valve implantation has become a therapeutic option for patients with symptomatic severe aortic stenosis and high risk for conventional valve replacement surgery. Although balloon valvuloplasty have been the first option for less invasive treatment using percutaneous technique in critically ill patients, its longterm results have shown high rates of restenosis as well as not improving the clinical condition of the patients1, which makes this procedure only as an option for a bridge in emergency surgery. More recently the indication of transcatheter aortic valve implantation has been increased as repair of failed biological aortic prostheses in high risk for operation2.

CASEREPORT 75-year-old male patient presenting biological valve prosthesis in the aortic position number 25 placed 11 years ago. He was admitted in the coronary care unit of University Hospital, Federal University of Mato Grosso do Sul with pulmonary edema and acute severe aortic valve failure.

Comorbidities such as renal failure not on dialysis, chronic obstructive pulmonary disease, severe left ventricular systolic dysfunction (ejection fraction 30%) made him a high-risk patients with Euroscore > 20%.

It was then performed transcatheter implantation of an aortic valve prosthesis: Braile Biomedica’s INOVARE. The inner diameter of aortic prosthesis (22 mm) was previously measured using echocardiography and angiography of multiple detectors. Therefore, we used a 24- prosthesis. The surgery was designed so that the implants were performed by transapical approach, however due to the team’s experience with transfemoral access due to the endovascular treatment of aortic diseases, we chose to implant this device via tranfemoral in a pioneer way. We used a femoral sheath Gore Dry Seal 24 Fr where the prosthesis together with its delivery balloon was introduced via the right femoral artery and carried using an extrastiff guide through the aorta until the level of the aortic prosthesis’ ring; under the guidance fluoroscopic and transesophageal echocardiography was expanded at the ring of the bioprosthesis. The echocardiographic images (Fig. 1) demonstrated the correction of severe aortic regurgitation without significant transvalvular gradient (15.20 mmHg) allowing, together with fluoroscopy (Fig. 2), 470

Fig. 1 - Image showing transesofagic echocardiogram demonstrating the presence of aortic valve regurgitation preoperatively and in the absence of imaging performed after transcatheter aortic valve implantation by transfemoral via

Fig. 2 - Image of fluoroscopy demonstrating the absence of reflux and the positioning of the transvalvular aortic valve prosthesis after transcatheter implantation by transfemoral via. Note also the maintenance of the left coronary trunk perfusion

DISCUSSION Due to high mortality of severe symptomatic aortic stenosis especially in high surgical risk patients the possibility of less invasive intervention using transcatheter

Pontes, JCDV ET AL - Pioneering transcatheter aortic valve Implant (Inovare®) via transfemoral

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aortic valve implantation, either femoral or apical via, has become an attractive alternative.

The first description of the catheter valve implant was made by Davies3, 1965. Only in 2002, Cribier et al. [4] proposed the transcatheter aortic valve implantation (TAVI) to treat severe aortic stenosis in symptomatic patients with high surgical risk.

Partner Trial (Placement of Aortic Transcatheter) [5], the first “Trial” in its group B randomized trial, which compared medical therapy with transcatheter valve implantation, demonstrated superiority of the intervention, both in terms of mortality and quality of life. In group A the “trial” of transcatheter aortic valve implantation showed no inferiority when compared to open surgery in a year of follow-up of patients with critical aortic stenosis without surgical conditions.

In our environment Gaia et al 6 reported a 30-day mortality found in 18.18% and overall mortality (42.42%) mainly attributed to infectious complications postoperatively. The fact that 39.39% of these patients underwent surgery in the presence of decomposition and prolonged hospitalization, induces a greater risk of colonization and infection. Survival after hospital discharge was quite favorable (90.7%), demonstrating that after the initial phase the result is sustained.

We believe that the idea of a new procedure is the trend that its appointment is reserved for exceptional cases, but it may cause a negative bias in the analysis of mortality.

The accomplishment of this procedure in end stage of heart failure of clinically decompensated patients, surely contributes to the emergence of postoperative complications, perhaps these extremely critical patients could benefit only from balloon valvuloplasty as a bridge to either the transcatheter valve implantation.

The implant by transapical approach is often chosen due to the incompatibility with sheaths of larger caliber and decreases the possibility of peripheral vascular complications. However the development of endovascular materials, such as stents and introducers are allowing greater ease in using the femoral approach, this would

minimize the harmful effects of thoracotomy on respiratory mechanics of these severe patients, which is known to be a risk factor for postoperative pulmonary infections.

Further studies with larger samples are needed to define the safety of the procedure along with the sedimentation of technical learning in the future may allow this procedure be recommended for less critical and more electives patients.

REFERENCES 1. Otto CM, Mickel MC, Kennedy JW, Alderman EL, Bashore TM, Block PC, et al. Three-year outcome after balloon aortic valvuloplasty. Insights into prognosis of valvular aortic stenosis. Circulation. 1994;89(2):642-50.

2. Bedogni F, Laudisa ML, Pizzocri S, Tamburino C, Ussia GP, Petronio AS, et al. Transcatheter valve-in-valve implantation using Corevalve Revalving System for failed surgical aortic bioprostheses. JACC Cardiovasc Interv. 2011;4(11):1228-34.

3. Davies H. Catheter mounted valve for temporary relief of aortic insufficiency. Lancet. 1965;1:250.

4. Cribier A, Eltchaninoff H, Bash A, Borenstein N, Tron C, Bauer F, et al. Percutaneous transcatheter implantation of an aortic valve prosthesis for calcific aortic stenosis: first human case description. Circulation. 2002;106(24):3006-8.

5. Leon MB, Smith CR, Mack M, Miller DC, Moses JW, Svensson LG, et al. Transcatheter aortic-valve implantation for aortic stenosis in patients who cannot undergo surgery. N Engl J Med. 2010;363(17):1597-607.

6. Gaia DF, Palma JH, Ferreira CB, Souza JA, Agreli G, Guilhen JC, et al. Implante transapical de valva aórtica: resultados de uma nova prótese brasileira. Rev Bras Cir Cardiovasc.

2010;25(3):293-302.

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Comparison between multiplanar and rendering modes in the assessment of fetal atrioventricular valve areas by 3D/4D ultrasonography Comparação entre os modos multiplanar e renderizado na avaliação da área das valvas atrioventriculares fetais por meio da ultrassonografia 3D/4D

Edward Araujo Júnior1, Liliam Cristine Rolo1, Christiane Simioni1, Luciano Marcondes Machado Nardozza1, Luciane Alves da Rocha1, Wellington P. Martins2-4, Antonio Fernandes Moron1

DOI: 10.5935/1678-9741.20120079

RBCCV 44205-1410

Abstract Objective: To compare the agreement of multiplanar and rendering modes in the assessment fetal atrioventricular valves (mitral and tricuspid) areas by three-dimensional (3D) ultrasonography using the software spatio-temporal image correlation (STIC).

Methods: We conducted a prospective cross-sectional study with normal pregnant women, with single fetuses, between 18-33 weeks. To measure the areas, we used the plan of fourchamber view. In the case of multiplanar, the plane was rotated on the axis “Z” form the heart to position at 9h. For rendering, the green line (region of interest - ROI) was placed from the atria of the heart perpendicular to the crux. The agreement was assessed by a Bland-Altman (limits of agreement) using the relative difference between the measures: ((rendering mode) - (multiplanar mode)) / (average).

Results: 328 fetuses were evaluated. We have not identified the occurrence of systematic error between methods: the average relative difference was 1.62% (-2.07% to 5.32%, confidence interval 95%) in the mitral and 1.77% (- 1.08% to 4.62%) in the tricuspid valve. The limits of agreement between methods were -65.26% to 68.51% for the mitral and -49.91% to 53.45% for the tricuspid.

Conclusions: There was no systematic error between modes and thus the observed values for the area of fetal atrioventricular valves can be used for comparisons needs to be corrected. However, relatively large variations may be observed when repeating the measurement area by different modes.

1. Division of Fetal Cardiology, Department of Obstetrics, Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil.

2. Department of Obstetrics and Gynecology, Faculty of Medicine of Ribeirão Preto, University of São Paulo (FMRP-USP), Ribeirão Preto, SP, Brazil.

3. School of Ultrasound and Medicine of Ribeirão Preto Recycling (EURP), Ribeirão Preto, SP, Brazil.

4. National Institute of Science and Technology (INCT) of Hormones and Women’s Health, Ribeirão Preto, SP, Brazil.

Correspondence address Edward Araujo Júnior Department of Obstetrics, Federal University of São Paulo (UNIFESP) Rua Carlos Weber, 956 apto. 113 – Visage – Alto da Lapa – São Paulo, SP, Brazil – Zip code 05303-000 E-mail: araujojred@terra.com.br

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Keywords: Comparison; Fetus; Atrioventricular valves; Area; Three-dimensional ultrasonography.

Article received on August 4th,2012 Article accepted on August 27th,2012

Araujo Júnior et al. - Comparison between multiplanar and rendering modes in the assessment of fetal atrioventricular valve areas by 3D/ 4D ultrasonography

Abbreviations, acronyms & symbols 2D 3D 4D AFI CAPES LMP ROI SPSS STIC UNIFESP

Two-dimensional Three-dimensional Four-dimensional Amniotic fluid index Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Last menstrual period Region of interest Statistical Package for the Social Sciences Spatio-temporal image correlation Federal University of São Paulo

Resumo Objetivo: Avaliar a concordância entre as medidas das áreas das valvas atrioventriculares (mitral e tricúspide) fetais realizadas por ultrassonografia tridimensional (3D) pelo software spatio-temporal image correlation (STIC) usando os modos multiplanar e renderizado.

Métodos: Estudo prospectivo de corte transversal avaliando fetos de gestações únicas, consideradas saudáveis, entre 18 a 33 semanas de idade gestacional. Para a medida das áreas, utilizou-se o plano de quatro câmaras cardíacas.

INTRODUCTION Approximately 8% of birth defects are cardiac malformations and 50% of these are considered major factors that increase early and late mortality rates. Developmental disorders of the chordae and papillary muscles, such as thickening and partial or total agenesis of valvular tissue are primarily responsible for dysplasia, atresias, and mitral and tricuspid valve defects of varying degrees as well as other important disorders [1].

Spatio-temporal image correlation (STIC) facilitates cardiac volume acquisition and stores the data for later analysis and reconstruction of the anatomy by presenting an image in the multiplanar and rendering mode showing the positioning of vessels; it also enables real-time assessment of movement throughout a cardiac cycle by using the cine loop technique [2]. The multiplanar mode displays the image in three orthogonal planes (axial, sagittal, and coronal), which can be manipulated in all three axes (x, y, z). The order rendered by the determination of virtual planes allows for better morphological assessment of cardiac structures such as the septum and the atrioventricular valves [3]. A few studies in the literature have evaluated the area of the atrioventricular valves using

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No caso do multiplanar, o plano foi rodado no eixo “z” de forma o coração se dispuser em 9h. Para o renderizado, a linha verde (região de interesse - ROI) foi posicionada a partir dos átrios, perpendicular à cruz do coração. A concordância foi avaliada pelo método de Bland-Altman (limites de concordância) utilizando a diferença relativa entre as medidas: ((modo renderizado) – (modo multiplanar)) / (média).

Resultados: 328 fetos foram avaliados. Não identificamos a ocorrência de erro sistematizado entre os métodos: a diferença relativa média foi de 1,62% (-2,07% a 5,32%, intervalo de confiança de 95%) na mitral e de 1,77% (-1,08% a 4,62%) na tricúspide. Os limites de concordância entre os métodos foram de -65,26% a 68,51% para a mitral e de 49,91% a 53,45% para a tricúspide.

Conclusões: Não foi observado erro sistematizado entre os modos e desta forma os valores observados para a área das valvas atrioventriculares fetais podem ser utilizados para comparações sem necessidades de correções. Entretanto, variações relativamente grandes podem ser observadas ao se repetir a medida da área pelos diferentes modos.

Descritores: Comparação. Feto. Valvas atrioventriculares. Área. Ultrassonografia tridimensional.

STIC, but no studies have compared the use of multiplanar and rendered imaging [4].

The objective of this study was to compare multiplanar and rendering three-dimensional (3D) ultrasonography using STIC for the evaluation of fetal atrioventricular valves in normal pregnant women.

METHODS We conducted a prospective cross-sectional study evaluating the healthy fetuses of singleton pregnancies between 18 and 33 weeks of gestational age. The Ethics Committee of the Federal University of São Paulo (UNIFESP) approved the study (nº 0135/10), and all patients who agreed to participate voluntarily signed a consent form. Inclusion criteria were singleton pregnancies with a live fetus and gestational age determined by last menstrual period (LMP) and confirmed by ultrasound in the first trimester. Exclusion criteria were as follows: oligohydramnios (amniotic fluid index [AFI] below the 5th percentile for gestational age according to the table proposed by Moore and Cayle) [5]; a fetus with a dorsal anterior presentation (between 11 o’clock and 1 o’clock); fetuses with an estimated weight 2 473

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standard deviations above or below the mean according to the table proposed by Hadlock et al. [6]; pregnant women with chronic diseases that could affect fetal growth and development; strong attenuation of the sound beam due to maternal obesity and abdominal scarring; fetal malformation diagnosed by ultrasonography; and women who were smokers and/or users of illicit drugs.

The examinations were performed by a single examiner (LCR), and all pregnant women were evaluated only once; no postnatal results were obtained. All examinations were performed using a Voluson 730 Expert (General Electric Medical Systems, Healthcare, Zipf, Austria) device equipped with a convex volumetric transducer (Rab4-8L).

Analyses were performed offline by the same examiner using 4D View software (version 9.0, GE Medical Systems, GmbH & Co OHG).

Cardiac volumes were acquired by segmenting the four cardiac chambers (reference plane); most of the time the fetus was lying with the spine at the 6 o’clock position. An acquisition angle of 20–40° and an acquisition time of 10– 15s were standard. To measure the area of the atrioventricular valves by the rendering method, the heart was rotated along the “z” axis such that the cardiac apex was at the 6 o’clock position. We used the green line (region of interest [ROI]) positioned from the atrium bordering the cross of the heart. The area measurements were performed manually during early ventricular systole, at which time, both valves were fully opened (Figure 1A). For the multiplanar method, the heart was rotated along the “z” axis so that the heart apex was at the 9 o’clock position and the atrioventricular valves were visualized automatically in the sagittal plane (Figure 1B). The measurements were performed in the same way as for the rendering method.

Fig. 1 - (A) Rendering image of atrioventricular valve at the initial moment of ventricular systole, with the extent of their respective areas performed manually. (B) Image by multiplanar method of atrioventricular valves in the sagittal plane at the time of initial ventricular diastole and the extent of their respective areas (MI: mitral, TC: tricuspid)

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Data were stored in Excel 2007 (Microsoft Corp., Redmond, WA, USA) and analyzed using Statistical Package for the Social Sciences (SPSS) version 18.0 for Windows (SPSS Inc., Chicago, IL, USA) and GraphPad Prism version 5.0 for Windows (GraphPad Software, San Diego, CA, USA). Agreement was assessed using the BlandAltman method [7]. Evaluation of the correlation between absolute measures ([mode rendering] - [multiplanar mode]) revealed that this was highly dependent on the average measure (which in turn was dependent on gestational age).

In this case, the estimated limits of agreement would not be valid for the entire gestational period evaluated (they would be overestimated for the start of pregnancy and underestimated for the final stages). However, the relative difference ([rendering mode] - [multiplanar mode]/[average]) between the methods was relatively constant during the pregnancy assessments; therefore we have presented only those results.

RESULTS The initial sample comprised 340 women, but 12 patients were excluded from the study because of artifacts that occurred during cardiac volume acquisition (n = 10) or because the fetal weight was predicted to be above the 90th percentile (n= 2). Thus, 328 fetuses were evaluated in total. We did not detect any systematic error between methods: the average relative difference was 1.62% (95% confidence interval -2.07 to 5.32%) for the mitral valve and 1.77% (-1.08 to 4.62%) for the tricuspid valve. The limits of agreement between methods were -65.26 to 68.51% for the mitral valve and -49.91 to 53.45% for the tricuspid valve (Table 1, Figure 2).

DISCUSSION In this study, we compared multiplanar and rendering imaging for evaluating fetal atrioventricular valve area by 3D ultrasonography using STIC software. The advantages

Fig. 2 - (A) Average relative difference between multiplanar and rendering modes plotted against the difference of means for measuring the area of the mitral valve. (B) Average relative difference between multiplanar and rendering modes plotted against the difference of means for measuring the area of the tricuspid valve

Table 1. Evaluation of the relative agreement between methods for estimating the area of fetal atrioventricular valves by three-dimensional ultrasonography.

Average difference Lower limit for Upper limit for concordance concordance Mitral valve % (95% CI) 1.62 (-2.07 to 5.32) -65.26 (-86.83 to -43.69) 68.51 (46.93 to 90.08) Tricuspid valve % (95% CI) 1.77 (-1.08 to 4.62) -49.91 (-64.57 to -35.26) 53.45 (38.80 to 68.11) CI = confidence interval, relative difference = [(rendering mode) - (multiplanar mode)]/(average)

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of STIC for fetal cardiac evaluation are a reduced dependence on operator experience for obtaining diagnoses, and a shorter examination time for the acquisition of volumes and possibility to send data on patient volumes for analysis at centers of excellence in fetal cardiology [8]. Measuring the area of the atrioventricular valves is important for identifying early abnormal values and stenosis or weaknesses that could lead to severe hemodynamic disorders at birth. Such fetuses could be referred to intrauterine referral centers, decreasing the rates of perinatal morbidity and mortality.

The multiplanar method involves the evaluation of 3D orthogonal planes that are perpendicular to each other.

The advantage of this method of ultrasonography relative to traditional two-dimensional (2D) ultrasonography resides precisely in the possibility of assessing the same structure in all three planes, making it easier to visualize and measure the structure. Particularly, in case of single 3D scanning of heart valves, it is possible to measure the areas of these structures through a number of rapid adjustments. The rendering method allows detailed visualization of a structure by adjusting variables such as the gamma-chroma curve. These settings produce an image with sharper an edge, which is, theoretically, a more reliable measure [4,9].

In this study, we did not observe any systematic errors between methods, and therefore, we determined that the observed areas of the fetal atrioventricular valves could be used for comparison without correction requirements.

However, it should be noted that large variations were observed when the data were analyzed using the Bland– Altman method [7]. We believe that these variations were not because of sample size as an average of 20 patients were evaluated per gestational age, which is the number recommended by Royston for determining range values for parameters of fetal growth [10]. In addition, possible examiner bias was not a problem because all measurements were performed by a single examiner. This allows us to conclude that it is possible that the rendering method provided more reliable measurements of the area of the atrioventricular valves because they are small and irregular structures. However, only in vivo studies can confirm this assumption; however, such a study is not possible in our country because our laws do not permit the termination of pregnancy.

In summary, measurements of the area of fetal atrioventricular valves using both the multiplanar and rendering 3D ultrasound (STIC) methods were valid, but there were large variations between the techniques.

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ACKNOWLEDGMENTS We thank CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior) for providing financial support for Liliam Cristine Rolo.

REFERENCES 1. McElhinney DB, Silverman NH, Brook MM, Hanley FL, Stanger P. Asymmetrically short tendinous cords causing congenital tricuspid regurgitation: improved understanding of tricuspid valvular dysplasia in the era of color flow echocardiography. Cardiol Young. 1999;9(3):300-4.

2. Gonçalves LF, Lee W, Chaiworapongsa T, Espinoza J, Schoen ML, Falkensammer P, et al. Four-dimensional ultrasonography of the fetal heart with spatiotemporal image correlation. Am J Obstet Gynecol. 2003;189(6):1792-802.

3. Yagel S, Benachi A, Bonnet D, Dumez Y, Hochner-Celnikier D, Cohen SM, et al. Rendering in fetal cardiac scanning: the intracardiac septa and the coronal atrioventricular valve planes.

Ultrasound Obstet Gynecol. 2006;28(3):266-74.

4. Rolo LC, Nardozza LM, Araujo Júnior E, Simioni C, Zamith MM, Moron AF. Assessment of the fetal mitral and tricuspid valves areas development by three-dimensional ultrasonography.

Rev Bras Ginecol Obstet. 2010;32(9):426-32.

5. Moore TR, Cayle JE. The amniotic fluid index in normal human pregnancy. Am J Obstet Gynecol. 1990;162(5):1168-73.

6. Hadlock FB, Harrist RB, Martinez-Poyer J. In utero analysis of fetal growth: a sonographic weight standard. Radiology.

1991;181(1):129-33.

7. Bland JM, Altman DG. Statistical methods for assessing agreement between two methods of clinical measurement.

Lancet. 1986;1(8476):307-10.

8. Vinãls F, Mandujano L, Vargas G, Giuliano A. Prenatal diagnosis of congenital heart disease using four-dimensional spatio-temporal image correlation (STIC) telemedicine via an Internet link: a pilot study. Ultrasound Obstet Gynecol. 2005;25(1):25-31.

9. Rolo LC, Nardozza LMM, Araujo Júnior E, Simioni C, Zamith MM, Moron AF. Reference curve of the fetal ventricular septum area by the STIC method: preliminary study. Arq Bras Cardiol. 2011;96(5):386-92.

10. Royston P. Constructing time-specific reference ranges. Stat Med. 1991;10(5):675-90.

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Accessory mitral leaflet: an uncommon form of subaortic stenosis Folheto mitral acessório: uma causa incomum de estenose subaórtica

Marcos Alves Pavione1, José Teles de Mendonça2, Ivan Sérgio Espínola Souza3, Maria Amélia Fontes de Faria Russo4 DOI: 10.5935/1678-9741.20120080

RBCCV 44205-1411

Abstract Three-years-old boy presenting with a subvalvar aortic stenosis without a precise definition by echocardiography, where the surgical approach revealed an accessory mitral leaflet.

Resumo Criança de três anos, com estenose subvalvar aórtica sem definição precisa ao ecocardiograma, apresentando como diagnóstico cirúrgico um folheto mitral acessório.

Descritores: Mitral valve/surgery. Aortic stenosis, subvalvular. Heart valve diseases.

Descritores: Valva mitral/cirurgia. Estenose aórtica subvalvar. Doenças das valvas cardíacas.

INTRODUCTION Subvalvar aortic stenosis (SAS) corresponds to about 1% of congenital heart disease and usually presents in the form of membrane (narrow segment) or tunnel (longest segment) [1]. It is usually acquired and progressive. A rare cause of congenital SAS is the obstruction by accessory mitral valve tissue (AMT), approximately half of these corresponding to an accessory mitral leaflet (AML) [2].

There are few reports in the literature of patients with AMT, so that its incidence in children is not well established. It is known that about 70% of cases the diagnosis is performed in childhood (including neonatal) and often by signs or symptoms related to obstruction [3]. Performing echocardiograms in the same american institution for six years, Rovner A. et al. found an incidence of one case per 26,000 examinations [4]. They may present as isolated defect in 30% of cases, but usually is associated with other heart

1. Master’s Degree at Faculty of Medicine at University of São Paulo, Ribeirão Preto (FMRP-USP); Pediatric cardiologist and intensivist of Heart Hospital of Sergipe, Aracaju, SE, Brazil.

2. PhD at São Francisco de Assis Cardiovascular Foundation, Belo Horizonte, MG, Brazil. Director and cardiovascular surgeon at Heart Hospital of Sergipe, Aracaju, SE, Brazil.

3. Cardiovascular surgeon at Heart Hospital of Sergipe, Aracaju, SE, Brazil.

4. Pediatric cardiologist at Heart Hospital of Sergipe, Aracaju, SE, Brazil.

diseases, the most common being VSD, ventricular aneurysm and complex congenital heart disease [2,5].

We treated in our institution a 3-year-old brown boy, weighing 13 kilograms. He was the third child of healthy mother, aged 25. The story did not include notifiable gestational maternal complications, denying use of medications during pregnancy, except for vitamins prescribed by his physicians. There was no family history of congenital heart disease. The child’s medical history included epilepsy (tonic-clonic seizures), initially for one year, six months and controlled by the use of phenobarbital.

At eight months in a routine pediatric visit, a systolic murmur was heard, and the patient was referred to a cardiologist. Due to structural limitations of the public health system, only three years after he came to our clinic for correction. The patient never presented symptoms suggestive of heart failure or cyanosis.

This study was carried out at Heart Hospital of Sergipe, Aracaju, SE, Brasil.

Correspondence address: José Teles de Mendonça Rua Campos, 75 – São José – Aracaju, SE, Brazil – Zip code 49015220 E-mail: jteles@infonet.com.br Article received on May 2nd, 2012 Article accepted on July 22nd, 2012

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Abbreviations, acronyms & symbols AML AMT CPB LVOT SAS

accessory mitral leaflet accessory mitral valve tissue cardiopulmonary bypass left ventricular outflow tract subvalvar aortic stenosis

In the evaluation, the child was asymptomatic, stained, and cyanosis. Atypical facies. Cardiac auscultation revealed an ejective systolic murmur 3 + / 6 + best heard in the medium right sternal border, without irradiation, with absence of other sounds and a normal second sound. No reports of change in characteristics of sound during the Valsalva maneuver. Blood pressure was 110 x 70 mmHg, with adequate perfusion. He presents eupneic and without visceromegalies. No significant changes in other systems.

Chest radiography was normal and electrocardiogram showed sinus rhythm with no signs of ventricular hypertrophy. An echocardiogram during hospitalization showing situs solitus, atrioventricular and ventriculoarterial concordance, interatrial and interventricular intact septa.

But, calling attention to the presence of a parachute-like structure that bulged to the left ventricular outflow tract (LVOT) during systole (Figure 1), generating a whirling flow, with significant subvalvar stenosis (peak gradient of 77

Fig. 1 - Two-dimensional echocardiography in parasternal longitudinal cutting, showing the systolic bulging of the accessory mitral leaflet (arrows), obstructing the left ventricular outflow tract.

LA = left atrium, LV = left ventricle, RV = right ventricle

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mmHg) with slight acceleration of blood passing through the aortic valve (2.3 m / s). The mitral valve was morphologically and functionally normal. The aortic valve presented mild thickening without valve insufficiency under color flow. Was asked if the mitral valve chordae could generate redundant obstruction, and he was referred for surgical correction.

The surgery was performed without complications, with cardiopulmonary bypass (CPB) as current protocol at the hospital. The approach was by median sternotomy. The LVOT was approached by an oblique aortotomy (J-shape), and surgical findings presented as a subaortic stenosis by accessory mitral leaflet fixed on the ventricular face of the anterior leaflet of the mitral valve and spanned to the anterior septal region which was fixed by means of thickened chordae and a well-formed accessory papillary muscle (Figure 2). Finally, an atriotomy was also performed for better assessment of mitral valve and its leaflets. As the AML does not contribute to the maintenance of the mitral valve function, it was dried collectively, together with the wire ropes and the papillary muscle (Figure 3). The CPB time was 60 minutes, with aortic clamping for 45 minutes.

The postoperative course was favorable, leaving room extubated without complications in the postoperative period and remained in intensive care unit for 48 hours and was discharged on the fifth day. The echocardiogram performed on the fourth postoperative day showed no residual stenosis or valvular LVOT.

Fig. 2 - Oblique aortotomy showing the accessory mitral leaflet (AML), being suspended by wires. Ao = aorta, LV = left ventricle

Pavione MA, et al. Accessory mitral leaflet: an uncommon form of subaortic stenosis

Fig. 3 - Resected accessory mitral leaflet demonstrating the accessory papillary muscle (separately) and thickened rudimentary chordae

DISCUSSION The first report of AMT was performed in 1842 and the first description of surgical correction performed in 1963 [4]. The embryological origin of the defect comes from the incomplete separation of the mitral valve of the endocardial cushions [6-7]. AMT can be found on the ventricular face of the anterior leaflet of the mitral valve, the chordae or papillary muscle attachments.

A classification of types of AMT was suggested by E. Prifti et al, based on review of 90 cases described, depending on the deployment and the morphology of the defect. Type I (fixed), presents itself in two forms: AI (nodular) and IB (membranous). Type II (Mobile), is divided into two subtypes: IIA (pedunculated) and IIB (leaflet-like).

The latter corresponds to 46% of cases and is called the accessory mitral leaflet and may be further subdivided into leaflets with rudimentary chordae and chordae with well development [2].

In the case reported by us, the patient is classified as type II, subtype B, with rudimentary chordae.

An AMF may or may not produce LVOT obstruction.

In cases where there is obstruction or it is mild, patients usually present asymptomatic and diagnosed accidentally while performing an echocardiogram. When the

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obstruction is more important, it can be heard the typical murmur of subvalvular aortic stenosis of ejection and audible character in the second or third right intercostal space, and may radiate to the neck vessels. Besides the obstructive effect of the mass, the turbulence generated at the site of stenosis leads to gradual fibrosis, increase of the obstruction and secondary valve insufficiencies.

Symptomatic cases usually manifest themselves in the first decade of life and symptoms are related to obstruction presenting as dyspnea, syncope, or angina on effort [2].

Stroke is also a symptom related in some cases. Symptoms tend to appear when the obstruction is more important, identified by echocardiography in a high pressure gradient in the LVOT (peak gradient> 50 mmHg) [4].

The echocardiogram is considered the method of choice for the diagnosis of obstruction by AMT, allowing the quantification of stenosis and its hemodynamic effect, identifying the site of obstruction and also the classification of AMT in their different types [4,8]. The transthoracic technique is usually sufficient for this setting, but the TEE can facilitate analysis of the braids. In the specific case of accessory mitral leaflet, it can get a typical image on which parachute bulges LVOT during systole [9]. Catheterization adds very little to the findings, being suitable only for investigation of associated defects [2].

The management depends on the degree of obstruction and the clinical patient. In asymptomatic patients and usually without obstruction or mild obstruction, clinical and imaging approach can only be performed.

The surgery is oriented in symptomatic cases, also in those with moderate to severe cases of obstruction and those associated with other heart diseases requiring approach. Aortic failure is another indication regardless of the degree of obstruction [3].

The identification of a AMT during surgery can be difficult using only the aortotomy, and the left atriotomy can be a great help [10]. In a review covering 68 surgical patients found a mortality rate of 9%. Such mortality was associated with poor surgical outcome: the presence of other complex congenital heart disease, fail to complete removal of the tissue and surgeries performed in the neonatal period. The most common complications were mild residual stenosis in 13% of cases, and the reoperation for severe residual stenosis was also necessary in 13% of cases.

Mitral regurgitation (10%) or aortic (7%) [2] were the less common complications.

This case alerts us to the importance of prior knowledge of this pathology and clinical-surgical implications for the echocardiographic diagnosis can be performed more objectively, facilitating the classification of the type found in MRI, to a prior suitable handling and consistent surgical indication.

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REFERENCES 1. Rohliceck CV, del Pino SF, Hosking M, Miro J, Cote JM, Finley J. Natural history and surgical outcomes for isolated discrete subaortic stenosis in children. Heart.

1999;82(6):708-13.

2. Prifti E, Bonacchi M, Barlolozzi F, Frati G, Leacche M, Vanini V. Postoperative outcome in patients with accessory mitral valve tissue. Med Sci Monit. 2003;9(6):RA126-33.

3. Yuan SM, Shinfeld A, Mishaly D, Haizler R, Ghosh P, Raanani E. Acessory mitral valve tissue: a case report and an updated review of literature. J Card Surg. 2008;23(6):769-72.

4. Rovner A, Thanigaraj S, Perez JE. Accessory mitral valve in an adult population: the role of echocardiography in diagnosis and management. J Am Soc Echocardiogr. 2005;18(5):494-8.

5. Panduranga P, Eapen T, Al-Maskari S, Al-Farqani A. Accessory mitral valve tissue causing severe left ventricular outflow tract

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obstruction in a post-Senning patient with transposition of the great arteries. Heart Int. 2011;6(1):18-20.

6. Chevers N. Observations on diseases of the orifice and valves of the aorta. Vol. 7. London: Guyâ&#x20AC;&#x2122;s Hospital Reports;1842. p.387-452.

7. MacLean LD, Culligan JA, Kane DJ. Subaortic stenosis do to accessory tissue on the mitral valve. J Thorac Cardiovasc Surg.

1963;45:382-7.

8. Souza AM, Silva CE, Ortiz J, Matsumoto AY. Accessory mitral valve leaflet echocardiographic diagnosis. Arq Bras Cardiol.

1990;55(2):121-4.

9. Rivera IR, Silva MAM, Fernandes JMG, Cavalcanti RC. Accessory mitral valve leaflet. Rev Bras Ecocardiog. 2008;21:49-51.

10. Prifti E, Frati G, Bonacchi M, Vanini V, Chauvaud S. Accessory mitral valve tissue causing left ventricular outflow tract obstruction: case reports and literature review. J Heart Valve Dis. 2001;10(6):774-8.

CASE REPORT

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Aortic pseudoaneurysm as cause of superior vena cava syndrome: a case report Pseudoaneurisma de aorta como causa de síndrome da veia cava superior: relato de caso

Katsuro Harada Júnior1, Renato Garcia Lisboa Borges2, Renata Kiyoko Borges Harada3

DOI: 10.5935/1678-9741.20120081

RBCCV 44205-1412

Abstract The superior vena cava syndrome represents the set of signs and symptoms resulting from obstruction of superior vena cava. The syndrome has as main causes malignant tumors such as bronchogenic carcinoma, lymphoma and mediastinal metastases. Lung cancer accounts for 80% of cases, mediastinal lymphomas by 15% and 5% correspond to other causes. This case report aims to present an unusual case of this syndrome, which occurred in a male patient after penetrating wound in the chest, which developed a pseudoaneurysm of the aortic arch and superior vena cava syndrome.

Resumo A síndrome da veia cava superior representa o conjunto de sinais e sintomas decorrentes da sua obstrução. A síndrome tem como principais etiologias tumores malignos, como o carcinoma broncogênico, o linfoma e a metástase mediastinal. O câncer de pulmão é responsável por 80% dos casos, os linfomas mediastinais por 15%, e 5% correspondem às demais causas. Este relato de caso objetiva apresentar um caso incomum dessa síndrome, ocorrido em um paciente do sexo masculino após ferimento penetrante no tórax, resultando em pseudoaneurisma de arco aórtico e a síndrome da veia cava superior.

Descriptors: Wounds, stab. Superior vena cava syndrome.

Aneurysm, false. Aorta.

Descritores: Ferimentos perfurantes. Síndrome da veia cava superior. Falso aneurisma. Aorta.

INTRODUCTION The superior vena cava syndrome (SVCS) is characterized by a set of clinical signs and symptoms resulting from obstruction of that vessel. This syndrome is presented in various ways, according to the severity of the obstruction and its cause. In general, a complete obstruction caused by neoplastic disease evolves rapidly to death, while that resulting from benign pathologies can even be asymptomatic [1].

The SVCS presents various clinical signs and symptoms, such as headache, facial flushing, edema and the development of chest collateral circulation. Other commonly

1. Specialist in cardiovascular surgery; Gaspar Vianna Foundation Clinical Hospital , Belém, PA, Brazil.

2. Medical Student, University of the State of Pará 3. Medical Student, University of the State of Pará

Work carried out at Gaspar Vianna Foundation Clinical Hospital, Belém, PA, Brazil.

reported symptoms are dyspnea on exertion, orthopnea, dizziness and visual disturbances [1-3].

The superior vena cava (SVC) obstruction is mainly related to malignant tumor processes such as bronchogenic carcinoma, lymphoma and mediastinal metastasis. As nonmalignant causes, we can mention tumor diseases as teratoma and thymoma, radiation, mediastinal fibrosis, pneumothorax and thoracic aortic aneurysm, especially in the aortic arch and ascending portion. Several other conditions are related to SVCS, since any factor that causes a compression of the SVC is a possible etiology, including transvenous pacing and aortic pseudoaneurysm [1-5].

This case report aims to describe an unusual

Correspondence address: Renato Garcia Lisboa Borges Travessa Pirajá, 1330 – Marco – Belém, PA Brazil – Zip Code: 66095-631 E-mail: renato_borges15@hotmail.com

Article received on May 4th, 2012 Article accepted on August 30th, 2012

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and space, normal coloured, hydrated, eupneic, anicteric, presenting cyanosis, tachycardia, blood pressure within normal limits, jugular stasis with bruising in the right subclavian region and swelling in the upper limbs, chest and face.

The patient underwent cardiac monitoring, oxygen delivery via nasal catheter and chest radiograph was performed. After radiological analysis, which showed widening of the mediastinum, Doppler echocardiography was requested for better diagnosis.

The echocardiogram reported technical difficulties due to local edema, yet revealing mild diastolic restriction, with an ejection fraction of 73%, normal vessel diameter and cardiac chambers, as well as the aortic arch and descending aorta without changes.

Because of this result and no availability at the FHCGV of a functioning CT scanner, an arteriography and a venography were requested.

On an arteriography (Figure 1A) and venography (Figure 1B), a pseudoaneurysm was visualized in the anterior and lateral aortic arch near the origin of the brachiocephalic trunk, compressing the SVC, confirming the diagnosis of posttraumatic SVCS.

Abbreviations, acronyms & symbols CPB SW SVCS SVC

cardiopulmonary bypass stab wound superior vena cava syndrome superior vena cava

presentation of SVCS, occurred in a male patient after penetrating chest injury resulting in pseudoaneurysm of the aortic arch and SVCS. CASE REPORT A 25-year-old male patientpatient was assisted at Gaspar Vianna Foundation Clinical Hospital (FHCGV), complaining of “chest pain”. Victim of stab wound (SW) with more than 48 hours of evolution, presenting cutting-perforating injuries sutured in the sternal region and right subclavian, with local pain and bruising. The patient also complained of pain during inspiration.

The patient was in good general condition according to a physical examination, conscious and oriented in time

A

B

Fig. 1 - Image of arteriography of the ascending aorta and aortic arch (A) and venography of brachiocephalic vein and SVC (B).

Arrows indicate the location of the pseudoaneurysm and the compression points in VCS

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Fig. 2 - Photographic documentation of the surgery with the identification of the pseudoaneurysm. Arrow identifying the pseudoaneurysm

With the confirmation of diagnosis and because of the high likelihood of rupture of the pseudoaneurysm at the opening, the patient was referred for surgical treatment, where we performed a partial sternal thoracotomy for cardiopulmonary bypass (CPB), opting for right atrium and right femoral artery cannulation. After performing the installation of CPB, thoracotomy was completed, which caused the rupture of the pseudoaneurysm which was quickly controlled the bleeding (Figure 2).

With the identification of the orifice of approximately two inches, located in the aortic arch, close to the innominate artery, suture was performed with simple reinforcement of bovine pericardium with no need of circulatory arrest. Later, usual procedures were performed for the weaning from CPB and closure of the patient. With the confirmation of the diagnosis, there was no need for histopathology.

After surgery, the patient progressed satisfactorily and was discharged on the ninth postoperative day.

DISCUSSION The majority of patients with SVCS presents aged 50 to 70 years. Age is related to the primary cause of the syndrome, which are the malignant tumor processes.

Children can also be affected, being caused mainly by nonHodgkins lymphoma or benign causes [3].

As already reported, the symptoms of SVCS can include a feeling of heaviness in the head, cough and dyspnea.

Clinical findings may include facial and neck edema, presence of collateral circulation on the trunk, upper extremities and neck, facial flushing, cyanosis, stridor, anxiety and neurological signs may be present [1,3]. On

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physical examination, the patient had presented jugular stasis and swelling of arms, chest and face, signs that corroborate the suspicion of this syndrome, but as noted, the patient had a history of SW for more than 48 hours, this time was not enough so that the patient could present collateral circulation, since collateral vessels takes several weeks to accommodate blood flow diverted from the VCS. Thus, the presence of collateral circulation is not common in cases of SVCS with rapid evolution [6].

After completion of the examination which showed widening of the mediastinum on chest radiographs and noncompletion of diagnosis by echocardiography, there would be the need to perform a chest CT angiography whose advantage would include a shorter time to image acquisition when compared to magnetic resonance angiography (MRA). The CTA is essential for assessment of SVCS, by clearly identifying the cause of the syndrome, the extent of disease, place and degree of venous obstruction [2]. Such resources were unavailable in the service in question, so we opted for realization of venography and arteriography, which revealed the injury (pseudoaneurysm) located in the aorta close to the innominate artery and the consequent compression of the SVC. In SVCS, the recognition of the risk of life and symptoms suggestive of airway involvement or cerebral edema is essential to reduce the risks of complications. If there is evidence of airway compromise, as stridor, associated with findings such as laryngeal edema or tracheal obstruction tomography abnormalities, the patient should be treated as a medical emergency, requiring interventions for airway protection, such as, for example, the endotracheal tube [1].

Treatment of SVCS is based on etiology. The patient had an aortic pseudoaneurysm, requiring immediate treatment, since traumatic rupture of the thoracic aorta is a surgical emergency, often fatal in the first few hours after injury [7].

Among the endovascular treatment options, some authors have reported success using stents with exclusion of the pseudoaneurysm. In some cases, the endovascular treatment may be combined with surgical, using percutaneous balloon to occlude the orifice of the pseudoaneurysm, a procedure that precedes the elective surgical repair [8].

The use of an endovascular stent constitutes one option of treatment for less invasive aortic diseases and may be considered an alternative to conventional surgical treatment.

The advantages of endovascular treatment compared to surgical correction of aortic diseases include: avoiding thoracotomy, cardiopulmonary bypass and minimizing the complications of an open procedure [7].

In the treatment of SVCS, angioplasty with placement of stent is currently the method that provides faster relief of SVC obstruction. After stent placement, the headache is 483

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immediately relieved, facial edema in 24 hours, while the swelling of the upper limbs and trunk is resolved within 72 hours, on average. To avoid thrombogenic complications, most patients perform prophylaxis with anticoagulants and antiplatelet agents [3, 8].

4. Costa R, Leão MIP, Silva KR, Camargo PR, Costa RV. Marcapasso bi-atrial epicárdico subxifóide na obstrução da veia cava superior. Arq Bras Cardiol. 2006;87(4):e101-3.

REFERENCES 1. Wan JF, Bezjak A. Superior vena cava syndrome. Hematol Oncol Clin North Am. 2010;24(3):501-13.

2. Joji M, Ryoko M, Shin-Ichiro M, Yoshio H, Yuhei S, Noriyuki S, et al. Superior vena cava obstruction caused by ascending aortic pseudoaneurysm as assessed by multidetector row computed tomography. J Cardiol Cases.

2011;3(2):e98-e102.

3. Nunnelee JD. Superior vena cava syndrome. J Vasc Nurs.

2007;25(1):2-5.

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5. Vydt T, Coddens J, Wellens F. Superior vena cava syndrome caused by a pseudoaneurysm of the ascending aorta. Heart.

2005;91(4):e29.

6. Kim HJ, Kim HS, Chung SH. CT diagnosis of superior vena cava syndrome: importance of collateral vessels. AJR Am J Roentgenol. 1993;161(3):539-42.

7. Buz S, Zipfel B, Mulahasanovic S, Pasic M, Weng Y, Hetzer R. Conventional surgical repair and endovascular treatment of acute traumatic aortic rupture. Eur J Cardiothorac Surg.

2008;33(2):143-9.

8. Ibáñez Maraña MA, Gutiérrez Alonso V, Cenizo Revuelta, N, San Norberto García EM, González Fajardo JA, Río Solá L, et al. Combined treatment, endovascular and surgical treatment of postraumatic pseudoaneurysm in the aortic arch. EJVES Extra. 2006;12(3):25-9.

CLINICAL-SURGICAL CORRELATION

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Aneurysm of the left atrium in a child with patent ductus arteriosus and mitral valve prolapse Aneurisma de átrio esquerdo em criança com persistência do canal arterial e prolapso da valva mitral

Danielle Lilia Dantas Tukamoto1, Carlos Henrique De Marchi1, Lilian Beani1, Ulisses Alexandre Croti1

DOI: 10.5935/1678-9741.20120082 Descriptors: Heart aneurysm. Ductus arteriosus. Mitral valve.

RBCCV 44205-1413 Descritores: Aneurisma cardíaco. Canal arterial. Valva mitral.

CLINICAL DATA Infant 9 months, 6.5 kg, female with history of dyspnea during feeding and poor weight gain. Born at term weighing 3.2 kg. In the first month, was diagnosed with congenital heart disease with increased pulmonary hemodynamic, being the child sent from her hometown for surgical treatment.

Physical examination showed malnutrition with weight below the percentile 3 for age, tachydyspneic, acyanotic and pale. Hyperdynamic precordium with apical impulse deviated to the left and chest bulging to the left. Continuous murmur 3 + / 6 +, with multiple clicks in the left infraclavicular region. Liver 3 cm from the right costal margin. Large and palpable peripheral pulses in all four limbs.

ELECTROCARDIOGRAM Sinus tachycardia with frequency of 150 beats / min, SAQRS + 60 °, and atrial and left ventricular (Figure 1).

Fig. 1 - Electrocardiogram showed sinus tachycardia, atrial and ventricular overload

1. Pediatric Cardiovascular Surgery Service of São José do Rio Preto - Hospital de Base - School of Medicine of São José do Rio Preto, SP, Brazil.

Work performed at the Department of Pediatric Cardiovascular Surgery of São José do Rio Preto - – Hospital de Base – School of Medicine of São José do Rio Preto, SP, Brazil.

Correspondence address: Ulisses Alexandre Croti Hospital de Base – Faculdade de Medicina de São José do Rio Preto – FAMERP – Avenida Brigadeiro Faria Lima, 5544 CEP 15090-000 – São José do Rio Preto – SP – Brazil E-mail: uacroti@uol.com.br Article received on August 10th, 2012 Article accepted on September 17th, 2012

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Abbreviations, acronyms e symbols bpm PDA

beats per minute Patent Ductus Arteriosus

RADIOGRAPHY Enlarged cardiac area, cardiothoracic ratio of 0.61, an increase of left atrium and left ventricle. Increased pulmonary vascular network (Figure 2).

ECHOCARDIOGRAM Patent ductus arteriosus (PDA) with 7.09-mm and 4.48 mm aortic end in the lung. Mitral valve prolapse with mild to moderate degree. Dilation of the left atrium and moderate dilation of the left ventricle. Preserved ventricular function (Figure 3).

Fig. 2 - Chest radiography with cardiothoracic ratio of 0.61 and increased pulmonary vasculature. R: Right, L: left

A

C

B

D

Fig. 3 - (A) Image showing four chambers cut in aneurysmal dilatation of the left atrium. (B) Doppler flow by color with moderate mitral regurgitation. (C) Measures of the patent ductus arteriosus, length (8.99 mm) and aortic (7.09 mm) and lung (4.48 mm) ends. (D) Flow through the ductus arteriosus gradient between the aorta and the pulmonary artery of 71.12 mmHg

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DIAGNOSIS The clinical condition was compatible with the acyanogenic congenital heart disease with increased pulmonary blood flow, but not so usual effects of PDA in volume overload of the left chambers were potentiated by the presence of mitral valve prolapse with significant regurgitation. There is a clear indication of late immediate surgical treatment with echocardiographic monitoring aspect of the left atrium and mitral valve function [1,2].

SURGERY During monitoring, it was possible to observe the clinical symptoms, with significant bulging chest to the left (Figure 4). The operation was performed routinely by left posterolateral thoracotomy, small incision, opening the parietal pleura, dissection of the PDA region close to the aorta, identification of anatomical structures, passing two 4-0 polypropylene threads around the canal, being one at the aortic end and the other at the pulmonary end and strongly bound, interrupting the blood flow passage. Suture of the parietal pleura, chest tube and chest closure performed by planes.

The child progressed well and was discharged on the third postoperative day and the echocardiogram revealed significant reduction of mitral valve prolapse and trivial regurgitation.

Fig. 4 - Important left bulging chest by an enlarged cardiac silhouette due to aneurysm of the left atrium associated with patent ductus arteriosus with mitral valve prolapse. R: Right, L: left

REFERENCES 1. Zonnenberg I, de Wall K. The definition of a haemodynamic significant duct in randomized controlled trials: a systematic literature review. Acta Paediatr. 2012:101(3):247-51.

2. Schneider DJ, Moore JW. Patent ductus arteriosus. Circulation.

2006;114(17):1873-82.

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MULTIMEDIA

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Robotic assisted minimally invasive surgery for atrial septal defect correction Cirurgia minimamente invasiva robô assistida na correção da comunicação interatrial

Robinson Poffo1, Alex Luiz Celullare2, Renato Bastos Pope3, Alisson Parrilha Toschi3

DOI: 10.5935/1678-9741.20120083

RBCCV 44205-11414

Descriptors: Heart septal defects, atrial. Surgical procedures, minimally invasive/methods. Robotics.

Descritores: Comunicação interatrial. Procedimentos cirúrgicos minimamente invasivos/métodos. Robótica.

CHARACTERIZATION OF PATIENT The characteristics of the patient are: female, 24 years old, 55 kg. She came to our department with complaints of fatigue and palpitations. She denied any associated disease or medication use. On physical examination, the patient was eutrophic, eupneic at rest, without edema. No alterations of pulmonary auscultation and cardiac auscultation revealed a sinus rhythm, with pulmonary systolic murmur with fixed splitting of 2nd heart sound. Resting blood pressure (BP) was: 100/70 millimeters of mercury (mmHg).

The chest radiograph showed normal heart size and increased pulmonary vasculature. Echocardiography revealed a normal left atrial dimension (LA) of 2.9 centimeters (cm) and left ventricular (LV) diameter within normality (LV Systolic Diameter: 2.5 cm - LV Diastolic Diameter: 4.2 cm ) and normal myocardial thickness. The other cavities were also normal. The presence of interatrial comunication (IAC) secundum ostium type showed the Doppler that the shunt with unidirectional flow of LA to the right. The ejection fraction was estimated at 72% (Simpson). The pulmonary

artery pressure was estimated at 40 mmHg and increased pulmonary blood flow: 1.5 cm /second (cm/s).

The electrocardiogram showed sinus rhythm with right bundle branch block.

After discussing the clinical case, the surgery to repair the IAC was indicated. In a conversation with the patient after the explanation of the techniques type available to the IAC and also signed informed consent, she chose the robot-assisted minimally invasive approach [1].

Surgical correction consisted of atrial septal defect with a bovine pericardial patch. The duration of extracorporeal circulation (EC) was 63 minutes (min) and aortic clamping, 38 min.

The patient was extubated in the operating room; the postoperative bleeding was 340 milliliters (ml), length of ICU stay of 14 hours, had a great postoperative evolution and was discharged on the 2nd day after surgery. On the discharge day, the echocardiogram showed a normal ventricular function and an intact atrial septum, with well positioned patch without residual shunt.

THE VIDEO PERTINENT TO THE TEXT IS PUBLISHED ON THE JOURNAL WEBSITE: http://www.rbccv.org.br/video/v27n3

Study carried out at Albert Einstein Hospital, São Paulo, SP, Brazil.

1. Master in Surgery from the Federal University of Paraná, Coordinator of the Center for Minimally Invasive Cardiac Surgery and Robotics of the Albert Einstein Hospital, São Paulo, SP, Brazil.

2. Cardiovascular Surgeon at the Center for Minimally Invasive Robotic Cardiac Surgery, Albert Einstein Hospital, São Paulo, SP, Brazil.

3. Cardiovascular Surgeon at Albert Einstein Hospital, São Paulo, SP, Brazil, and Hans Dieter Schmidt Hospital, Joinville, SC, Brazil.

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Correspondence Address: Robinson Poffo 672/01 Albert Einstein Avenue, - Block A-1, room 421 - São Paulo, SP, Brazil – Zip code: 05652-901 E-mail: drpoffo@einstein.br There is no conflict of interest in this work.

Article received on July 25th, 2012 Article accepted on August 30th, 2012

Poffo R, et al. - Robotic assisted minimally invasive surgery for atrial septal defect correction

Abbreviations, Acronyms & Symbols LA IAC EC cm cm/s RICS Fr l/min AAL MAL RML min ml mmHg BP PTFE

Left Atrium Interatrial Communication Extracorporeal Circulation Centimeters Centimeters/seconds Right Intercostal Space French Liters/minute Anterior Axillary Line Midaxillary Line Right Midclavicular Line Minutes Mililiters Millimeters of Mercury Blood Pressure Polytetrafluoroethylene

DESCRIPTION OF SURGICAL TECHNIQUE The patient was intubated using Robert Shaw probe intubation, for selective lung ventilation and positioned with the right chest elevated at 20 °, with the arm alongside the body. Disposable pads for external cardiac defibrillation were placed in the region of the right scapula and anterolateral hemithorax. We performed the passage of nasopharyngeal thermometer and transesophageal transducer [2].

After central venous puncture through the right internal jugular vein and placement of double-lumen catheter, the same jugular vein was punctured in its proximal portion, and, through the Seldinger technique, a Bio-Medicus ® arterial cannula (Medtronic, Inc.) No. 17 French (Fr) was introduced. The puncture was guided by ultrasound in right internal jugular vein and the cannula located in the region of the superior vena cava.

Initially the markings were made for surgical access (Figure 1). After preparing the skin, sterile transparent plastic adhesive was applied across the exposed area (3M Steri Drape®). Following the markings, three incisions were made in the right mammary groove: (1) a more anterior one of 0.8 cm to place an 8mm trocar to the right atrial retractor located between right midclavicular (RML) and the anterior axillary lines (AAL), (2) the second one measuring 1.2 cm for the introduction of a 12 mm trocar to the optics located 1 cm above the AAL and the third incision (3) for the working trocar measuring 2 cm, located after the AAL. The trocar into the right atrial retractor was introduced into the chest through the 5th right intercostal space (RICS) and the other two entered the chest cavity through the 4th RICS. Then, two more 0.8 cm incisions were made for the trocars and 8mm for the robot arms, the first (4) into two RICS near the

Rev Bras Cir Cardiovasc 2012;27(3):488-90

AAL, and another (5) at the 6th RICS, 2 cm after the AAL. A sixth incision (C) of 0.5 cm was made at the midaxillary line for introducing the transthoracic aortic clamp. CO2 was continuously blown into the operative field at a rate of 3 liters / minute (l / min) through the trocar to the optic, which had a side entrance.

Fig. 1 - Preoperative Marking and locations for introduction: 1.

Right atrial retractor 2. Optics, 3. Working trocar 4. Left arm of the robot 5. Right-arm of the robot, C. transthoracic aortic clamp.

HL: Hemiclavicular line, AAL: anterior axillary line

After systemic heparinization, EC was established by cannulation of the femoral vessels, and the skin was incised in the right inguinal groove and the femoral vessels were cannulated using the Seldinger technique under direct vision. For arterial cannulation, Bio-Medicus cannula ® No 19 Fr (Medtronic, Inc.) was used, and for venous line, Bio-Medicus ® multistage femoral cannula No. 21 Fr (Medtronic, Inc). For perfect positioning of the cannulas, we used transesophageal echocardiography. It was then initiated EC. Vacuum-assisted venous drainage was used.

The patient was maintained at 32°C. Before the introduction of the trocars, the right lung was selectivated. The trocar was located to the optics and a micro-camera was introduced. The right hemithorax was inspected and, subsequently, other trocars were inserted.

Approximation was conducted with DaVinci robotic system (Intuitive Surgical Inc., Sunnyvale, CA) and connected to the trocars (Figure 2). The clamps used in the surgical procedure were specific for this robotic system and consisted of: large needlecases, Cardiere tweezers, DeBakey tweezers, scissors and dynamic atrial retractor. Under optical vision, the pericardium was opened 2 cm parallely and anteriorly to the phrenic nerve. This incision extended from the superior to the inferior vena cava. The pericardium was pulled by two stiches, which were exteriorized through the chest wall using a retractor / hook. Both vena cava were dissected and tied with heart ribbon.

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Poffo R, et al. - Robotic assisted minimally invasive surgery for atrial septal defect correction

Fig. 2 - External aspect of the operative field: DaVinci® robotic system connected to trocars

Through the second RICS, transthoracic aortic clamp (Chitwood clamp - Fehling, Inc.) was introduced in the midaxillary line (MAL). By using thoracoscopy, the ascending aorta was clamped and punctured with a 30cm metal needle(Geister, Inc.) for administration of hypothermic antegrade cardioplegia (6°C) with (Custodiol ®)HTK solution. At the puncture site, a purse-string suture was performed with polytetrafluoroethylene (PTFE) (Gore-tex ® - CV-3) wire. The opening of the right atrium was performed parallelly to the atrial septum and removal done with the aid of a specific robotic surgical retractor.

From the opening of the right atrium until its closure, the CO2 insufflation flow rate of 3 liters / min was maintained, with the goal of reducing the possibility of air embolism [3].

With the introduction of optics in the right atrium, IAC ostium secundum type was visualized with some remnants membranes, which was resected. Using measurements acquired by three-dimensional echocardiography, a compatible pericardial patch was made to fit the hole. The suture patch on IAC edges was performed continuously with PTFE (Gore-tex ® - CV-4) wire. Deaeration maneuvers of left chamberwere performed before completing suturing the pericardial patch with lung inflation. The right atrium was also closed through continuous suture in two layers of PTFE (Gore-tex ® - CV-4) wire. Both vena cava were untied. The purse-string suture in the ascending aorta was left open in the puncture site for cardioplegia, so that residual air of the ascending aorta could be evacuated.

After appropriate deaeration, and checked by transesophageal echocardiography, the aorta was unclamped and the patient rewarmed.

After weaning from EC, another transesophageal echocardiogram was performed to demonstrate that the

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bovine pericardium was well located and absence of residual shunt. The femoral vessels were decannulated and heparin reversed. Concomitantly, the right internal jugular vein was decannulated and achieved hemostasis by compression.

After review of hemostasis, the pericardium was closed by 2-0 braided polyester sutures. The chest drain was exteriorized through the trocar orifice of the right arm of the robot and placed inside the pericardial sac. It was kept in negative aspiration of 20 mmH2O. The accesses were closed in layers, first the muscle and then the subcutaneous tissue with poligalactina 910 (Vicryl Plus ® - Ethicon) 2-0 and 3-0 wires. Intradermal stiches were used for skin sutures with polyglycolic acid (PGA Monocryl ® - Ethicon) 4-0 colorless cutting needle. The remaining holes with less than 1 cm were closed using simple stitches made by nylon 5-0 (Figure 3). The dressings were performed with Opsite (Smith & Nephew Plc ®).

Fig. 3 - Final surgical aspect of the operative field

REFERENCES 1. Argenziano M, Oz MC, Kohmoto T, Morgan J, Dimitui J, Mongero L, et al. Totally endoscopic atrial septal defect repair with robotic assistance. Circulation. 2003;108(Supp 1):II191-4.

2. Poffo R, Pope RB, Selbach RA, Mokross CA, Fukuti F, Silva Junior I, et al. Cirurgia cardíaca videoassistida: resultados de um projeto pioneiro no Brasil. Rev Bras Cir Cardiovasc.

2009;24(3):318-26.

3. Poffo R, Pope RB, Toschi AP, Mokross CA. Plastia valvar mitral minimamente invasiva videoassistida: abordagem periareolar. Rev Bras Cir Cardiovasc. 2009;24(3):425-7.

Rev Bras Cir Cardiovasc 2012;27(3):491-2

Letter to the Editor

DOI: 10.5935/1678-9741.20120084

The medical education and SUS: what we have and what we want!

RBCCV 44205-1415

to health and on the rational use of the health network whose resources are finite.

Sincerely,

Dear Editor, Vinícius José da Silva Nina, São Luís/MA Brick offers us, in the article “The medical education and SUS” [1], with a clear and elegant reflection on the role of SUS in the formation of human resources for health. In this composition three actors are involved: the University as a builder organ; SUS, while integrated and hierarchized network and field of teaching and learning; and community, while user and representative of social control. From this perspective, we expect graduates from medical courses with a formation that resembles our European colleagues certified as “GPs” - General practitioner [2]. The logic of this model lies in de-hospitalization of health care, considering that with the strengthening of primary care, it would be possible to reach a staggering 80% of solvability of the 200 more prevalent nosologies in any territory. With that, we would have a network of secondary and tertiary care faster and more effective in solving the most complex cases.

Unfortunately, we are far from reaching this level of organization, because increasingly “in-service teaching” becomes weaker due to the asymmetry of choice possibilities with which the young doctor have to face.

The choice of teaching career in public universities, for example, is becoming less attractive. The adjunct-assistantprofessor, with a workload of 40 hours weekly, receives monthly a base salary of less than $ 1,000.00 (one thousand dollars), and it is expected: teaching, research, extension, guidance for theses, publishing and much more.

Therefore, the Academy needs to be strengthened in light of the Hippocratic principle highlighted by Brick on which “Medicine is science and art” [1], while in SUS the doctrine that education is one of its goal should be rescued, therefore, our obligation as a health professional, being teacher or not. And finally, the community needs to be counseled about the full exercise of its constitutional right

Full Professor. Professor of Medicine, Federal University of Maranhão (UFMA). General Director of the University Hospital of UFMA. Specialist in Health Services Management/MS. Titular Member of BSCVS.

REFERENCES 1. Brick AV. O ensino médico e o SUS. Rev Bras Cir Cardiovasc. 2012;27(2):331-3.

2. Witter S, Fretheim A, Kessy FL, Lindahl AK. Paying for performance to improve the delivery of health interventions in low- and middle-income countries. Cochrane Database Syst Rev. 2012 Feb 15;2:CD007899.

Quo Vadis “Evaluating scientific quality is a notoriously difficult problem which has no standard solution.”

Per O Seglen

The rise of the BJCVS impact factor (IF) of 0.963 (2011) to 1.293 (2012), representing an increase of 28.7%, is an important and very representative fact. Leadership obtained at that time, in the area of surgery in Brazil, is very welcome [1].

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Letter to the Editor

The need to locate, analyze and assess scientific study was initially proposed by Bush (1945), and culminated in the organization of the National Library of Medicine, the Impact Factor and also the Journal Citation Reports of the Institute for Scientific Information (ISI), with participation of Eugene Garfield (1955) [2,3].

The calculation for the IF of a journal in a given year (X) is performed as follows: IF of year X = No. of journal citations obtained in the two previous years ÷ No. of articles published in the two previous years [2].

In addition to IF, there are over 30 levels of measurements. In the words of Garfield (2006). “Impact Factor is not a perfect tool to measure the quality of articles but there is nothing better and it has the advantage of already being in existence and is, therefore, a good technique for scientific evaluation” [4].

But we must always improve, but how? In “The Secret of visibility”, Maurício da Rocha e Silva, editor of Clinics, highlights important points for IF increase: the language of science is English, publishing good articles with high impact (from the editorial board members) , publication of specific supplements of a particular subject and maintaining the journal with snapshot open access (allowing greater visibility of articles published) [5].

An interesting analysis published in the European Heart Journal (2012) sought to relate factors that may predict publications and citations (from abstracts submitted to scientific conferences). Using data from the 2006 European Congress of Cardiology, in which 10,020 abstracts of scientific studies were sent, the average of published studies subsequently was 38%. We identified prospective, randomized and controlled studies and inclusion of a number of patients ≥ 100 as independent factors of acceptance for publication [6].

We reached and outscored 1.0. Quo Vadis?

Helcio Giffhorn - Cardiovascular surgeon, Member of BSCVS- Curitiba/PR

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REFERENCES 1. Gomes WJ. Elevação do fator do impacto. Available from URL: h t t p : / / w w w. s b c c v. o r g . b r / m e d i c a / e x i b e C o n t e u d o Multiplo.asp?cod_Conteudo=660 2. Ruiz MA, Greco OT, Braile DM. Fator de impacto: importância e influência no meio editorial, acadêmico e científico. Rev Bras Hematol Hemoter. 2009;31(5):355-60.

3. Garfield E. Citation indexes for science: a new dimension in documentation through association of ideas. Science.

1955;122(3159):108-11.

4. Garfield E. The history and meaning of the journal impact factor. JAMA. 2006;295(1):90-3.

5. Marcolin N, Zorzetto R. O segredo da visibilidade. Pesquisa FAPESP. 2012;191:28-33.

6. Winnik S, Raptis DA, Walker JH, Hassun M, Speer T, Clavier PA, et al. From abstract to impact in cardiovascular research: factors predicting publication and citation. Eur Heart J 2012 Jun 5 [Epub ahead of print].

Cone Technique - José Pedro da Silva Another technique developed by a Brazilian Cardiac Surgeon: Dr. José Pedro da Silva, discloses his technique abroad, showing the potential for development of cardiovascular surgery in our country It is the “Cone” technique for correction of Ebstein’s anomaly. The recognition was already patent by adopting the procedure at centers in the United States and Europe. The concept now crystallizes, with the invitation to Dr. José Pedro da Silva, by American Heart Association, to present the details of the surgery and its long-term results, at the Annual Congress of the entity to be held between 3-7 November in Los Angeles, California.

Rev Bras Cir Cardiovasc 2012;27(3):493

Reviewers RBCCV/BJCVS 27.3 Continuing the appreciation of the work of reviewers, follows below, the names of those who evaluated the papers published in this issue of Revista Brasileira de Cirurgia Cardiovascular / Brazilian Journal of Cardiovascular Surgery (RBCCV / BJCVS).

Domingo Braile Editor-in-Chief - RBCCV/BJCVS

Ana Maria Rocha Pinto e Silva

Marcos Aurélio Barboza de Oliveira

Anderson Benício

Marcos Vinicius Pinto e Silva

Bruno Botelho Pinheiro

Mauricio de Nassau Machado

Eduardo Augusto Victor Rocha

Melchior Luiz Lima

Eduardo Keller Saadi

Michel Pompeu Barros de Oliveira Sá

Eliana Márcia Sotello Cabrera

Neuseli Lamari

Fabio Papa Taniguchi

Nilson Antunes

Fernando Antonio Fantini

Olivio Souza Neto

Francisco Costa

Orlando Petrucci

Gilberto Venossi Barbosa

Otoni Moreira Gomes

Jarbas Dinkhuysen

Paulo Roberto Brofman

João Carlos Leal

Reinaldo Bestetti

José Honório Palma

Reinaldo Wilson Vieira

José Wanderley Neto

Renata Gabaldi

Karlos Alexandre de Sousa Vilarinho

Ricardo Carvalho Lima

Lindemberg da Mota Silveira Filho

Robinson Poffo

Luciano Albuquerque

Rubens Thevenard

Luiz Fernando Caneo

Vera Lucia dos Santos Alves

Marcelo Matos Cascudo

Walter José Gomes

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SOCIEDADE BRASILEIRA DE CIRURGIA CARDIOVASCULAR BRAZILIAN SOCIETY OF CARDIOVASCULAR SURGERY E-mail: revista@sbccv.org.br Sites: www.scielo.br/rbccv www.rbccv.org.br

RBCCV em números 26 anos de circulação ininterrupta Fator de Impacto 1,239 Consultada por leitores de 100 países

www.rbccv.org.br www.scielo.br/rbccv www.bjcvs.org

793.234 acessos no site próprio (www.rbccv.org.br) em 2011 402.309 acessos no site da SciELO (www.scielo.br/rbccv) em 2011 3540 visitantes diariamente 380,97 gigabytes (GB) transferidos, média de 1,04 GB por dia 21.902.562 impressões de páginas em 2011 (requisição do navegador de um visitante para uma página web que possa ser exibida), média diária de 60.007,02.

Presente em nas bases de dados Lilacs, Scielo, Latindex, Index Copernicus, Scopus, PubMed, Thomson Scientific (ISI), Google Scholar

Fig.1 – Número de acessos ao site da RBCCV em 2011

Fig. 2 – Transferência de bytes no site da RBCCV durante 2011

Fig. 3 – Número de impressões de páginas da RBCCV em 2011