Vascular News Issue 87 – September 2020 (US version)

September 2020 | Issue 87

Featured in this issue:

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8

Jon Boyle: The UK National Vascular Registry

COVID-19: Funding to assess impact on aortic dissection

Profile: Roberto Chiesa

page 29

page 20

Inaugural CX Aortic Vienna to take place online

The inaugural CX Aortic Vienna meeting will be livestreamed 8–11 September 2020 to an international, online audience, and will include registrant participation, interaction, and polling.

T

he programme will focus on all matters aortic—from the aortic valve to the iliac arteries. All known pathologies will be included, and imaging, diagnosis, and therapeutic options— open, endovascular, hybrid, and no intervention—will be applied to the length of the entire aorta, all the while keeping the patient front and centre. On each of the four days, the programme will cover abdominal and thoracic topics.

CX Aortic Vienna 2020 is brought to you with the participation of the Austrian Society of Vascular Surgery (ÖGG), the Italian Society of Vascular and Endovascular Surgery (SICVE), the Swiss Society for Vascular Surgery (SGG), and Aortic Surgery “HOW TO DO IT” (HTDI).

In the abdominal aortic section, there is an enduring fascination with the importance of diagnostic imaging modalities, as well as how to maintain endovascular aneurysm repair (EVAR) results, or instead turn to open repair. There will be dedicated discussion around open and endovascular choices to treat abdominal aortic aneurysm, with a focus on sac size and EVAR follow-up, ultrasound versus CT surveillance after EVAR, and current research into the best imaging modalities for EVAR. There is also a separate session on pathologies of the iliac vessels within the pelvis. In the juxtarenal section, the programme will explore methods to overcome the challenging aortic neck, using all manner of open and endovascular means.

In the thoracic aorta, there will be sections dedicated entirely to the aortic arch, and every aspect of dissecting aortic aneurysm, especially with regard to the timing of intervention. All treatment approaches will be considered and comparisons of open and endovascular methods made in a stepwise, methodical manner.

In the thoracoabdominal section, there remains obvious interest in spinal cord ischaemia and how to reduce the risk of this, with or without cerebrospinal fluid drainage.

In an important collaboration, the ÖGG will be joined by the SGG in the creation of a combined livestreamed programme.

The SICVE will also have a livestreamed programme and HDTI will show Aortic Techniques & Technologies.

A focus on decision-making in the patient’s interest

Roberto Chiesa (Milan, Italy) will be specially filming open and endovascular technical procedures of how to best manage the diseases of the arch of the aorta, considering whether to intervene or not based on the underlying pathology.

He will outline the importance of a forward-thinking, non-biased approach and running daily multidisciplinary meetings in the patient interest to decide which, if any, is the best treatment.

A comprehensive meeting on aortic therapies

Afshin Assadian (Vienna, Austria), the current president of the ÖGG, describes CX Aortic Vienna as a “comprehensive meeting on aortic therapies” taking in contributions from speakers covering a wide range of specialties.

Alexander Zimmermann (Zürich, Switzerland) comments that the livestream format will enable widespread participation, enabling all colleagues interested in vascular medicine “to participate and actively contribute to this event” easily, wherever they are in the world.

See page 10 for the CX Aortic Vienna programme.

Collaborative efforts seek to understand COVID-19 impact on vascular patients Amidst the continuing COVID-19 pandemic, concerns have mounted in the vascular community about the disruption to clinical routine. As vascular patients are particularly vulnerable to both COVID-19 and the effects of delayed surgical care, a need for collaboration, data, and practice changes has emerged.

Robert Cuff (Spectrum Health, Grand Rapids, USA) and Max Wohlauer (University of Colorado School of Medicine, Aurora, USA) have responded, founding the Vascular Surgery COVID-19 Collaborative (VASCC).

IN A RESEARCH LETTER PUBLISHED online on 29 July in the European Journal of Vascular and Endovascular Surgery (EJVES), Mario D’Oria (Trieste University Hospital, Trieste, Italy) and colleagues, on behalf of VASCC, outline the project and urge their vascular colleagues to get involved.

They write that VASCC was established to provide vascular surgeons from around the world with the opportunity to study the fundamental issues facing the vascular specialty through two distinct research projects.

The first project focuses on the impact of COVID-19 on scheduled vascular operations.

According to D’Oria et al, this element of the study “provides a mechanism to formally Continued on page 6

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September 2020 | Issue 87

New data in vascular access

VASCULAR ACCESS: NEWLY-PUBLISHED DATA

Six-month IN.PACT AV Access results show superiority of DCB angioplasty Just-published six-month results of the IN.PACT AV Access study show that drugcoated balloon (DCB) angioplasty is superior to standard angioplasty for the treatment of stenotic lesions in dysfunctional haemodialysis arteriovenous fistulas (AVFs). Furthermore, it was found to be non-inferior with respect to access circuit-related serious adverse events within 30 days.

T

hese results were published on 19 August in the New England Journal of Medicine (NEJM).

Robert Lookstein (Mount Sinai Health System, New York, USA) and colleagues note that long-term outcomes for standard percutaneous transluminal angioplasty (PTA)—the current recommended treatment for dysfunctional haemodialysis fistulas—are poor. DCBs delivering the antirestonotic agent paclitaxel may improve outcomes, they write.

In this prospective, single-blinded, 1:1 randomised trial, the investigators enrolled 330 participants across 29 sites in the USA, Japan, and New Zealand. Patients with new or restenotic lesions in native upper-extremity AVFs were eligible for participation.

After successful high-pressure PTA, participants were randomly assigned to receive treatment with either the IN.PACT AV drug-coated balloon (Medtronic) or a standard balloon.

Lookstein and colleagues detail that the primary effectiveness endpoint was target-lesion primary patency, defined as freedom from clinically-driven target revascularisation or access-circuit thrombosis during the six months after the index procedure.

They assessed the primary safety endpoint—serious adverse events involving the arteriovenous access circuit within 30 days—in a noninferiority analysis (margin of noninferiority 7.5 percentage points).

Lookstein et al write that a total of 330 participants underwent randomisation, with 170 assigned to receive treatment with a DCB and 160 assigned to receive treatment with a standard balloon.

Writing in NEJM, the authors report that, during the six months after the index procedure, target-lesion primary patency was maintained more often in participants who

had been treated with a DCB than in those who had been treated with a standard balloon (82.2% [125/152] vs. 59.5% [88/148]; difference in risk, 22.8 percentage points; 95% confidence interval [CI] 12.8–32.8; p<0.001).

In addition, they found that DCBs were noninferior to standard balloons with respect to the primary safety endpoint (4.2% [7/166] and 4.4% [7/158], respectively; difference in risk, -0.2 percentage points, 95% CI -5.5–5; p=0.002 for noninferiority).

In the NEJM paper, Lookstein et al detail that there has been a wide adoption of continuous haemodialysis through autologous AVFs. However, this has been associated with a high incidence of dysfunction caused by vascular stenosis within the fistula circuit, leading to inadequate haemodialysis.

Lookstein and colleagues acknowledge some limitations of the present study. For example, they note that the DCB has a different appearance than a standard balloon, which made a double-blind trial design “unfeasible”. In addition, the investigators recognise that further studies will be required to evaluate the safety and effectiveness of DCBs for the treatment of central vein obstruction, in-stent restenosis, or arteriovenous graft stenosis, as they investigated only lesions in AVFs. “Improvements in patency could potentially have significant benefits for patients, leading to longer periods of successful and uninterrupted dialysis, as well as reducing

This is the first US Food and Drug Administration [FDA]approved paclitaxelbased device since the controversy last year” the use of catheter-based dialysis and the substantial incidence of adverse events associated with this type of dialysis.”

Speaking to Vascular News, Lookstein commented on the clinical implications of the study: “We now have Level 1 evidence of a simple technology that is proven to be safe and effective at improving outcomes for patients with end-stage renal disease [ESKD] on haemodialysis.”

He continued: “This is the first US Food and Drug Administration [FDA]-approved paclitaxel-based device since the controversy last year, which is a testament not only to the incredible results seen in this trial, but also the significant needs of this population.”

The latest stories from the vascular world

News in brief

n AAA GUIDELINES: Why do the 2019 European Society for Vascular Surgery (ESVS) abdominal aortic aneurysm (AAA) guidelines and those published earlier this year by the UK National Institute for Health and Care Excellence (NICE) have discordant recommendations in several areas? Disparities in the guidelines can be explained, in part, by their differing perspectives, methodologies, and quality assurance, say Janet T Powell (London, UK) and Anders Wanhainen (Uppsala, Sweden).

For more on this story go to page 8. n VASCULAR ACCESS RCT: The results of a randomised controlled trial (RCT)—the Shunt simulation study— show that a new patient-specific computation model accurately calculated postoperative access flow.

As flow is related to maturation, the authors, Niek Zonnebeld (Maastricht, the Netherlands) and colleagues, argue that this model may potentially improve arteriovenous fistula (AVF) maturation rates.

For more on this story go to page 22. n EJVES IMPACT FACTOR RISE : When the 2019 journal impact factors were published earlier this summer, the European Journal of Vascular and Endovascular Surgery (EJVES) scored 5.328, an increase of 46% on the previous year. Editor-in-chief Florian Dick (Bern, Switzerland) and senior editor Bartin Björck (Uppsala, Sweden) explain the reasons behind this success and how it might affect the future of the journal.

For more on this story go to page 33.

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September 2020 | Issue 87

COVID-19 and vascular surgery

Collaborative efforts seek to understand COVID-19 impact on vascular patients Continued from page 1

assess the impact of surgical delay on patients with vascular disease and will investigate the natural history of those whose operations were postponed as a result of the pandemic”.

Covering five major areas of vascular practice and conditions—carotid, aortic, peripheral, venous, and haemodialysis—it will also evaluate alterations in surgical care provided in response to the pandemic, and changes in type and location of surgery performed.

VASCC also aims to address thrombotic complications of COVID-19. D’Oria and colleagues detail that this second project “seeks to investigate the possible thrombotic manifestations of the disease and to underline management practices under such circumstances”. They add that it will have four specific modules encompassing a wide range of thrombotic conditions of the arterial and venous systems: acute limb ischaemia, acute mesenteric ischaemia, symptomatic venous thromboembolism, and stroke.

D’Oria et al emphasise the unparalleled effects the ongoing COVID-19 pandemic has had on vascular surgery. “Not in our lifetime have we seen such a rapid and widespread cancellation of scheduled surgical operations,” they write, adding that nearly all hospitals in regions affected by the pandemic temporarily halted the performance of elective surgery at some point, and, for many of them, only emergency operations were being performed during the peak of the COVID-19 surge.

Broad participation required

In order to address the need for data and new protocols for vascular patients, D’Oria et al emphasise the need for global collaboration. “Worldwide coordinated efforts are needed to obtain high-quality data of sufficient power to overcome the limitations imposed by scattered gathering of information.”

They report that, as of 9 June, VASCC has received commitment from more than 200 collaborators encompassing 171 sites and 34 countries.

As of 9 June,

Mario D’Oria

A potential limitation of the study, the authors of the research letter acknowledge, is that some areas of the world might have been able to continue elective surgery so far during the pandemic. However, they stress that these regions may be affected in the future.

“Understanding the impact of the pandemic on the provision of vascular treatment could be useful to tailor better pathways of care,” they write.

“Obvious and urgent appetite” for research

In parallel to VASCC, the COVID-19 vascular service (COVER) trial is also capturing global data on vascular

There is an obvious and urgent appetite for research around the COVID-19 pandemic.”

VASCC

practice amidst the current pandemic.

D’Oria and colleagues see this as an example of an “obvious and urgent appetite” for research around the COVID-19 pandemic among physicians, institutions, and policymakers.

“We view these projects as complementary and encourage participation in both,” the authors of the VASCC research letter write.

With support from both the Vascular Society of Great Britain and Ireland (VSGBI) and the European Society for Vascular Surgery (ESVS), the COVER study is a multinational, prospective, observational study that is aimed at capturing the impact of the pandemic on global vascular surgery.

An international Vascular and Endovascular Research Network (VERN) project, the COVER study was designed to assess the provision, practice, and outcomes of vascular surgery and its effect on patients during the COVID-19 pandemic.

Sandip Nandhra (Newcastle University, Newcastle, UK) and Ruth Benson (VERN president, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK) are co-leads of the study alongside the VERN executive, with Chris Imray (University Hospitals Coventry and Warwickshire NHS Trust), the president of the VSGBI, and Athanasios Saratzis (University of Leicester, Leicester, UK) as chief investigators.

In line with the goals of VASCC, the aim of COVER is to capture global data on vascular practice amidst the current pandemic in order to better understand its impact on vascular patients. In addition, they seek to provide the international vascular community with usable data to improve care pathways for vascular patients in the face of predictable resurgences of COVID-19, or in the case of a future pandemic or natural disaster.

“An opportunity”

D’Oria et al recognise that a great number of patients may have had their procedures postponed due to COVID-19, which mandates an analysis of the consequences of a delay to their treatment. The importance of research, and of the unique research opportunities this situation presents, “should not be overlooked, but considered an opportunity,” they state.

“Vascular surgeons are often at the frontline of the treatment of thrombotic diseases, putting them in a privileged position to explore the topic”.

has received commitment from more than

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171 34 sites countries

8

September 2020 | Issue 87

Discussion

Aortic Patient outcomes

National Vascular Registry will record patients’ outcomes from devices implanted during AAA repair On 23 July, the Royal College of Surgeons of England announced that key details of medical devices implanted in patients during abdominal aortic aneurysm (AAA) repair are to be included in a national database starting immediately. These new additions to the database will also monitor long-term patient outcomes to identify problems as early as possible.

T

his announcement comes shortly after the Cumberlege review where it was recommended that a “central database should be created by collecting key details including the patient, the implanted device, and the surgeon”.

The National Vascular Registry (NVR) was created in 2013 to provide UK National Health Service (NHS) vascular units with information on their performance.

From 23 July 2020, the NVR began to include information on conventional vascular grafts used to repair AAA and stent grafts used for endovascular aneurysm repair (EVAR).

According to a press release, the aim of including this information in the registry is to help track the long-term outcomes of patients who have had

aortic devices implanted and to identify as early as possible if a device is failing.

This will allow patients with these devices to be closely monitoried and prevent device use in future patients if problems are identified.

Earlier in July, the Independent Medicines and Medical Devices Safety (IMMDS) review made a series of recommendations in its report, “First do no harm”. The report followed an independent review, led by Baroness Cumberlege, into the adverse impact three medical interventions had on patients: Primodos, sodium valproate, and pelvic mesh.

To improve patient safety, the review recommended that “a central database should be created by collecting key details including the patient, the implanted device, and the surgeon”.

The Royal College of Surgeons of England made this recommendation in evidence given to the review last year. By including information on aortic devices in its national databse, the NVR fulfils this recommendation.

Jon Boyle Jon Boyle, consultant vascular surgeon, clinical lead of the NVR, and vice president-elect of the Vascular Society of Great Britain and Ireland (VSGBI), commented: “We want to provide patients undergoing AAA repair with the best care and information possible. We therefore need to capture device information of grafts and stent grafts both at the time of implantation and also afterwards, by monitoring longterm performance. This will enable us to quickly identify if a particular device is failing, and should help reduce revision rates of surgery. This patient-centred, clinician-led initiative is a major step forward for the safety of patients having vascular surgery.”

Vascular News spoke to Jon Boyle about the NVR.

What do you perceive as the main value of the NVR?

The NVR is a clinical audit that vascular specialists use to monitor their practice.

Hospitals send data to the NVR and the NVR analyses these to provide information on their standard of clinical

Key differences between ESVS 2019 and NICE 2020 AAA guidelines explored A recent review article aimed to understand why the 2019 European Society for Vascular Surgery (ESVS) abdominal aortic aneurysm (AAA) guidelines and those published earlier this year by the UK National Institute for Health and Care Excellence (NICE) have discordant recommendations in several areas.

DIFFERENCES IN THE GUIDELINES CAN be explained, in part, by their differing perspectives, methodologies, and quality assurance, concluded Janet T Powell (Imperial College London, London, UK) and Anders Wanhainen (Uppsala University, Uppsala, Sweden and Umeå University, Umeå, Sweden) in the European Journal of Vascular and Endovascular Surgery (EJVES).

They emphasise that the preparation of any clinical practice guidelines demands a “rigorous and systematic approach,” with protocols for peer and patient review of guidelines, and write that it may, therefore, be “surprising” that there are some “very marked differences” between the two guidelines in question.

Powell and Wanhainen carried out a review of the approach, methodology, and evidence used by the two guideline committees. They detail that NICE guidelines “use a multidisciplinary committee to address a limited number of prospectively identified questions, using rigorous methods heavily reliant on evidence from randomised controlled trials [RCTs] supported by inhouse economic modelling, with the purpose of providing the best, cost-effective healthcare in the UK in 46 recommendations”.

On the other hand, the ESVS guidelines “use an

expert committee to encourage clinical effectiveness across a range of European health economies. ESVS guideline topics, but not questions, are prospectively identified, assessment of evidence was less rigorous, and 125 recommendations were made”.

Powell and Wanhainen note that NICE guidelines are directed at all healthcare practitioners (including vascular and endovascular specialists), providers, patients, and their families or carers in the UK. Furthermore, they have a strong health economic perspective. Conversely, the ESVS guidelines were developed for vascular surgeons to support best clinical practice across Europe, with its wide range of health economies and health infrastructure.

Unless there is greater harmonisation of guideline perspectives and methodology, controversy is bound to arise.”

care and patient outcomes.

This allows hospitals to know where they are doing well, as well as highlight areas that they can improve.

Is it important to document imaging findings?

Already, the AAA dataset captures individual patient anatomical details. These will be combined with device information. This will allow device performance to be assessed against aortic morphological features, potentially identifying anatomical features associated with good and less good outcomes.

Will the quality of data entry enable increased consecutive prospective data studies to be performed reliably?

The NVR is recognised as one of the most successful national audits under the Healthcare Quality Improvement Partnership (HQIP) umbrella, with high case asceratinment rates for aortic surgery (>90%) and strong evidence of quality improvement in AAA outcomes since 2013.

The new device dataset has been combined with a new field to record reinterventions and long-term outcomes.

This will provide data on individual device performance in comparison to peers over time.

Writing in EJVES, Powell and Wanhainen report that more up-to-date evidence searches by the ESVS committee partly explain the differences in recommendations for screening women. The NICE committee did not consider sex-specific analysis or evidence for thresholds for intervention but did rely on sex-specific modelling to support their advice to use endovascular aneurysm repair (EVAR) for ruptures in women. NICE recommendations to use open repair for ruptured AAAs in men aged <71 years was based on their inhouse economic modelling.

Furthermore, they write that NICE recommends an open first strategy for non-ruptured AAA mainly based on earlier RCTs and UK-specific economic modelling, while the ESVS guidelines recommend an EVAR-first strategy after consideration of modern, but lower quality, evidence from observational studies.

Similar reasons, together with the expert knowledge of endovascular specialists on the guidelines committee, explain differences in the recommended treatments of juxtarenal aneurysms.

Powell and Wanhainen conclude that it is principally the differences in perspective and methodology between the ESVS 2019 and NICE 2020 guidelines that have resulted in some discordant recommendations, adding that future ESVS guidelines “may benefit from more multidisciplinary input”.

They end with a warning that, “unless there is greater harmonisation of guideline perspectives and methodology, controversy is bound to arise”.

Powell was a member of the ESVS 2019 AAA guidelines committee, and Wanhainen, chaired the ESVS 2019 AAA guidelines writing committee and currently is a standing member of the ESVS Guidelines Committee.

September 2020 | Issue 87

10 Education

Aortic Event

CX Aortic Vienna 2020 programme Covering all matters aortic—from the aortic valve to the iliac arteries—the inaugural CX Aortic Vienna will take place across four days, from 8 to 11 September. The meeting will be livestreamed and include audience participation, interaction, and polling. Register now at cxsymposium.com/cxaortic/cx-aorticvienna/registration/. Times in CEST (Central European Summer Time) Day 1:

Day 2:

Day 3:

Day 4:

Tuesday, 8th September

Wednesday, 9th September

Thursday, 10th September

Friday, 11th September

Time:

Time:

Time:

Time:

15:30 - 20:30

Welcome and opening of inaugural CX Aortic Vienna Time: 15:30 - 16:30 CX Chairman: Roger Greenhalgh, London, UK Abdominal aortic aneurysm choices - open and endovascular Time: 16:30 - 17:30 Moderators: Chistoph Neumayer, Vienna, Austria & Martin Funovics, Vienna, Austria Industry Symposium: From Benchtop to Bedside: Elevating EVAR and TEVAR Time: 17:30 - 18:00 Chairing: Dittmar Böckler, Heidelberg, Germany Moderator: Ross Milner, Chicago, USA Arch - Ishimaru zone 0 (ascending aorta) frozen elephant trunk and endovascular choices Time: 18:00 - 19:00 Moderators: Joseph Bavaria, Philadelphia, USA & Günther Laufer, Vienna, Austria Industry Symposium: Innovation in aortic arch repair Time: 19:00 - 19:30 Arch Techniques & Technologies Time: 19:30 - 20:30 Moderator: Gustavo Oderich, Houston, USA

15:30 - 20:30

Austrian and Swiss livestream presentations (ÖGG / SGG) with audience participation and discussion Time: 15:30 - 16:30 Moderators: Afshin Assadian, Vienna, Austria & Benedikt Reutersberg, Zürich, Switzerland

15:30 - 20:30

Italian and SICVE livestream presentations with audience participation and discussion Time: 15:30 - 16:30 Moderators: Roberto Chiesa, Milan, Italy & Stefano Camparini, Cagliari, Italy

Sac size and EVAR follow-up Time: 16:30 - 17:30 Moderators: Afshin Assadian, Vienna, Austria & Alexander Zimmermann, Zürich, Switzerland

Optimal use of aortic imaging for diagnostic and influence of operative results Time: 16:30 - 17:30 Moderators: Martin Funovics, Vienna, Austria & Jos van den Berg, Lugano, Switzerland

Industry Symposium Time: 17:30 - 18:00

Industry Symposium Time: 17:30 - 18:00

Aortic arch - Zones 0, 1, 2, 3 Time: 18:00 - 19:00 Moderators: Joseph Coselli, Houston, USA & Rodney White, Torrance, USA

Iliac arteries and five-branch technique for type I endoleaks Time: 18:00 - 19:00 Moderators: Maarit Venermo, Helsinki, Finland & Afshin Assadian, Vienna, Austria

Best of CX and all abstracts Time: 19:00 - 19:30 Thoracic aortic dissections - types A and B Time: 19:30 - 20:30 Moderators: Stéphan Haulon, Paris, France & Juerg Schmidli, Bern, Switzerland

Best of CX and all abstracts Time: 19:00 - 19:30 Thoracic aortic dissections Timing of intervention Time: 19:30 - 20:30 Moderators: Stéphan Haulon, Paris, France & Roberto Chiesa, Milan, Italy

15:30 - 20:30

Swiss and Austrian livestream presentations (SGG / ÖGG) with audience participation and discussion Time: 15:30 - 16:30 Moderators: Alexander Zimmermann, Zürich, Switzerland & Sabine Wipper, Innsbruck, Austria Challenging abdominal aneurysm neck - juxtarenal issues Time: 16:30 - 17:30 Moderators: Jurgen Falkensammer, Vienna, Austria & Marek Ahrlich, Vienna, Austria Industry Symposium Time: 17:30 - 18:00 Thoracic endograft and thoracoabdominal repair Time: 18:00 - 19:00 Moderators: Günther Laufer, Vienna, Austria & Alexander Zimmermann, Zürich, Switzerland Best of CX and all abstracts Time: 19:00 - 19:30 Thoracic endograft and thoracoabdominal repair (continued) Time: 19:30 - 20:30 Moderators: Maarti Venermo, Helsinki, Finland & Roberto Chiesa, Milan, Italy

Aortic Vienna Register at cxsymposium.com/cxaortic for the inaugural CX Aortic Vienna livestream (8–11 September 2020), with a programme focused on cardiovascular aortic advances and classical open and endovascular solutions.

AORTIC VIENNA

8â&#x20AC;&#x201C;11 SEPTEMBER 2020 We would like to invite all specialists treating patients with aortic disease to attend the inaugural CX Aortic Vienna meeting, which will be livestreamed 8â&#x20AC;&#x201C;11 September 2020 to an international, online audience, and will include registrant participation, interaction, and polling.

Registration open

www.cxaortic.com

September 2020 | Issue 87

12 Journal coverage

Aortic Imaging

Prospective 4D ultrasound imaging study provides new insights into AAA stability

A recent prospective study concludes that characterisation of wall kinematics by time-resolved three-dimensional ultrasound (4D ultrasound) provides a “new and independent criteria” for the distinction of diseased tissue in the abdominal aortic aneurysm (AAA) sac and the less affected neck region. The study’s findings were published online in the European Journal of Vascular and Endovascular Surgery (EJVES).

AUTHORS WOJCIECH DERWICH (JW Goethe University Hospital, Frankfurt am Main, Germany) and colleagues write that previous studies have demonstrated the kinematic differences of aortic wall deformation according to age and cardiovascular pathology, but in this study, the pathological wall motion in the AAA is described for the first time.

The authors describe the results of their comparison of AAA sac and neck wall motion with 4D ultrasound imaging as a “promising step” towards the establishment of new biomarkers to differentiate between the mechanical instability of the AAA and rupture risk.

Derwich et al detail that the clinical decision between elective aneurysm repair or continuation of conservative therapy is based on the assessment of

AAA rupture risk. They add that while the determination of aneurysm diameter allows for follow-up of aneurysm growth, it fails in precisely predicting aneurysm rupture. Precise rupture prediction for the individual AAA “remains a challenge,” they write.

In the present study, Derwich and colleagues investigate 4D ultrasound based on wall motion indices (WMIs) to see if they are capable of distinguishing between uneven affected regions of the aneurysm wall.

Using 4D ultrasound, the investigators examined a total of 56 patients with an AAA. Local longitudinal, circumferential, and shear strains were computed using custom methods.

They characterised the deformation of the neck and sac of each aneurysm by statistical indices of the obtained

Use of IVUS in the treatment of type B aortic dissection with TEVAR is associated with improved longterm survival A recent study, published in the August issue of the Journal of Vascular Surgery (JVS), concludes that intravascular ultrasound (IVUS) was independently associated with improved long-term survival following thoracic endovasular aneurysm repair (TEVAR) for type B aortic dissection (TBAD).

A

uthors Nathan Belkin (Hospital of the University of Pennsylvania, Pennsylvania, USA) and colleagues detail that IVUS examination was used in the majority of TBAD and was used more often in acute TBAD. Belkin and colleagues emphasise the “ever important” role of IVUS in today’s clinical practice pattern of treating TBAD due to the reliance of TEVAR on true lumen access. IVUS—the authors state— permits the positional confirmation of wire over which

distributions of local wall strains (WMIs): mean and peak strain, heterogeneity index, and local strain ratio. The locations of regions with highest local peak strain were determined.

Derwich and colleagues report in EJVES that, compared with the aneurysm neck, the sac is characterised by low mean strain, but highly heterogeneous deformation, described by high local strain ratio and heterogeneity index. Differences were highly significant (p<0.001) for all strain components.

Furthermore, they write that the regions with the highest circumferential peak strain were found more often in the posterior part of the aneurysm neck (p<0.5) and sac (p<0.001) regions, compared with other wall regions.

Finally, they found no statistically significant correlation between the

The correlation of WMIs with aneurysm rupture risk has to be investigated in further studies.”

the device is to be deployed in the true lumen.

However, the authors highlight that IVUS examination is not universally used in the application of TEVAR to TBAD due to a lack of “convincing data” on outcomes.

Belkin et al performed a retrospective review of TEVARs performed for TBAD in the national Vascular Quality Initiative (VQI) from January 2010 to August 2018. Data collected included demographics, intraoperative and postoperative variables, and long-term mortality. They used multivariable logistic regression to evaluate variables associated with IVUS use and mortality, and performed Cox regression for adjusted survival analysis.

The investigators report that of 2,686 patients (average age 60.4 years, 69.3% male) included in the study, IVUS examination was used in 74.6% of cases.

They detail that IVUS patients were younger (60 years vs. 61.7 years, p=0.004), more often male (72.1% vs.

61.3%; p<0.001), exhibited less coronary disease, but had higher preoperative creatinine (1.27±0.89mg/dl vs.

1.14±0.68mg/dl; p<0.001) and were more often treated in the acute setting (55.2% vs. 49.7%, p=0.03).

“Interestingly,” the authors write in JVS, there were no differences in contrast use (117.4±77.6ml vs.

123±81.9ml; p=0.11) or fluoroscopy time (20.3±16.5 minutes vs. 19±22.1 minutes; p=0.1).”

However, IVUS cases had a greater number of devices implanted (1.84 vs. 1.65; p<0.001), higher rates of Zone 0–2 proximal seal (43.9% vs. 30.7%; p<0.001), higher rates of distal seal zones beyond the diaphragm (53.9% vs. 37.4%; p=0.001), and larger proximal and distal graft diameters, with no differences in postoperative renal function.

IVUS patients also had higher rates of follow-up

WMIs and maximum AAA diameter, except for longitudinal mean strain, which decreased with the increasing diameter (rho=-0.42, p<0.1).

Derwich et al write that in previous studies WMIs, obtained by mechanical modelling and statistical analysis based on 4D ultrasound measurements have been proposed as mechanical biomarkers for the pathophysiological state of the individual AAA wall.

In the current study, WMIs are shown to be capable of characterising the kinematic differences between AAA sac and neck non-invasively in vivo.

With larger mean and homogenous deformation, described by lower local strain ratio and heterogeneity index for all strain components, the WMIs indicate the morphologically and functionally less pathological elastic behaviour of the AAA neck: compliance (or stiffness) and the degree of heterogeneity of the elastic properties are close to those observed in aged, non-aneurysmal aortas. In contrast, the sac is characterised by advanced overall stiffening and heterogeneity of local elastic deformation.

While the quantitative analysis of WMIs and local evaluation of the deformation pattern promises new insights in the non-invasive stratification of aneurysm stability, they note that the correlation of WMIs with aneurysm rupture risk has to be investigated in further studies.

imaging (61.3% vs. 54.8%; p=0.003), larger maximum aortic diameters at follow-up, and more reinterventions over time.

The number of aortic devices (odds ratio [OR] 1.56; 95% confidence interval [CI] 1.24–1.97; p<0.001), malperfusion indication (OR 1.68; 95% CI, 1.17–2.42; p=0.005) and distal seal zone beyond the diaphragm (OR 1.64; 95% CI 1.3–2.07; p<0.001) were independently associated with IVUS use, whereas female gender showed a trend towards less IVUS use (OR 0.79; 95% CI 0.62–1.01; p=0.063).

After controlling for age, preoperative comorbidities, and postoperative complications like spinal cord ischaemia, IVUS was associated with a 61% decrease

This is the first study to date showing long-term mortality benefits associated with the use of IVUS examination.” in the odds of mortality (OR 0.39; 95% CI 0.2–0.78; p=0.008), with a clear survival advantage shown in adjusted survival curves.

Belkin and colleagues conclude: “This is the first study to date showing long-term mortality benefits associated with the use of IVUS examination. Further study is needed to understand these patterns and potentially influence guidelines instructing the use of IVUS during TEVAR for TBAD.”

September 2020 | Issue 87

14 Journal coverage

Aortic AAA repair

Five-year survival following EVAR for ruptured AAA “improving,” study concludes “The relative survival benefit of EVAR over open repair has increased over time,” conclude Rens RB Varkevisser (Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, USA) and colleagues in the July edition of the Journal of Vascular Surgery (JVS). This conclusion was based on a retrospective review of Society for Vascular Surgery (SVS) Vascular Quality Initiative (VQI) data that show five-year survival after endovascular aneurysm repair (EVAR) for ruptured abdominal aortic aneurysm (AAA) has improved over time, whereas survival after open repair has remained constant.

T

he authors note that increasing experience and improving technology have led to the expansion of EVAR for ruptured AAA. Therefore, they set out to investigate whether the five-year survival after both EVAR and open repair for ruptured AAA has changed over the last 14 years.

This study was designed to investigate whether five-year survival after EVAR and open repair for ruptured AAA has improved over time, and to compare EVAR with open repair in patients treated early in the EVAR experience and patients treated contemporarily, to ascertain if a survival difference has emerged over time.

Varkevisser et al identified repairs for ruptured infrarenal AAA within the VQI registry between 2004 and 2018 and compared five-year survival of both EVAR and open repair between the early (2004–2012) and late (2013–2018) cohorts.

Within the 2004–2018 VQI database, they identified

VQI analysis finds endovascular repair of rAAA superior to open repair A recent study examining the effect of operative approach on outcomes in patients presenting with ruptured abdominal aortic aneurysm (rAAA) demonstrated clear short- and midterm survival benefits of endovascular repair over an open approach.

THE AUTHORS—LINDA J WANG (Massachusetts General Hospital, Boston, USA) and Mahmoud B Malas (University of California San Diego, San Diego, USA)—add that these benefits persisted after matching on all major demographic, comorbid, and anatomic variables. In addition, patients undergoing open repair used more hospital resources, with longer length of stay, higher estimated blood loss, longer procedure times, and higher complication rates.

4,638 ruptured AAA repairs, which included 409 EVARs in the early cohort and 2,250 in the late cohort, as well as 558 open repairs in the early cohort and 1,421 in the late cohort.

The authors report that propensity matching resulted

In matched EVAR patients, five-year survival was higher in the 2013– 2018 cohort (63%) than in the 2004–2012 cohort (49%)

Malas et al, writing in the Journal of Vascular Surgery (JVS), suggest a more aggressive endovascular approach for rAAA in patients with suitable anatomy.

The authors note that even with repair, rAAA has a mortality rate ranging from 20–50%. While endovascular aneurysm repair (EVAR) has provided an “attractive, less invasive alternative to open surgical repair,” with the potential to reduce the high mortality associated with rAAA intervention, the literature remains “mixed” on whether EVAR provides a survival benefit over open repair for rAAA. Wang et al argue that the three randomised controlled trials (RCTs) that examined the effects of operative strategy on rAAA outcomes were “poorly designed and heavily criticised,” and therefore “limited in their real-world applicability”. As a result of this, the investigators sought to compare the two treatment modalities using a propensitymatched analysis in a ‘real-world’ setting.

They cite “high crossover rates, small sample sizes, and restrictive exclusion criteria” could, in part, explain why their results differ from these large trials. Of note, however, the largest of the three RCTs in question—the IMPROVE (Immediate management of patients with rupture: open versus endovascular repair) trial, which enrolled 613 patients across 30 centres—did in fact reveal a survival advantage and reduced costs

2013–2018

63%

in 366 matched pairs of late versus early EVAR and 391 matched-pairs of late versus early open repair.

When comparing EVAR with open repair, propensity matching resulted in 277 matched pairs of early EVAR versus open, and 1,117 matched pairs of late EVAR versus open.

In matched EVAR patients, five-year survival was higher in the late cohort (63% vs. 49%; hazard ratio [HR], 0.77; 95% confidence interval [CI], 0.61–0.97; p=0.027), whereas there was no difference between matched late versus early for open repair patients (52% vs. 59%; HR, 1.04; 95% CI, 0.85–1.28; p=0.69).

In the early cohort, there was no survival difference between EVAR and open repair (51% vs. 46%; HR, 0.88; 95% CI, 0.69–1.11; p=0.28). However, in the late cohort EVAR was associated with higher survival compared with open repair (63% vs. 54%; HR, 0.69; 95% CI, 0.6–0.79; p=0.001).

Varkeivisser and colleagues caution: “This was a retrospective analysis and therefore could not adjust for decisions based on certain anatomic restrictions, making it likely that at least some of the open repairs would not have been candidates for EVAR”.

They also address the fact that this study only investigates midterm outcomes. “Both the rate of late adverse outcomes other than mortality, as well as the outcomes after five years, should be subject to further investigation,” they remark.

vs

2004–2012

49%

compared with open repair at three years, in keeping with the findings of the present study. “However,” says Malas, “this study suffered from large cross over between the two treatment arms after randomisation. The analysis was based on intention to treat”.

Wang and Malas analysed all ruptured cases of open surgical repair and EVAR in the Vascular Quality Initiative (VQI) between 2003 and 2018. They compared raw and propensity-matched EVAR and open surgical repair cohorts.

Writing in JVS, the investigators detail that there 4,929 rAAA repairs perfomed—2,749 EVAR and 2,180 open repair. They report that, compared with EVAR patients, open repair patients had higher rates of myocardial ischaemic events (15% vs. 10%; p<0.001), major adverse events (67% vs. 37%; p<0.001), and 30-day death (34% vs. 21%; p<0.001).

On adjusted analysis, open repair

Wang et al suggest a more aggressive endovascular approach for rAAA in patients with suitable anatomy.”

was predictive of 30-day mortality (odds ratio 1.8, 95% confidence interval [CI] 1.5–2.2). After 1:1 matching, the study cohort consisted of 724 pairs of open and EVAR cases. The open repair patients had twice the length of stay (median 10 days [interquartile range 5–19 days] vs. five days [interquartile range 3–10 days]; p<0.001).

Furthermore, univariate analysis demonstrated persistent increased 30day mortality after open repair (32% vs. 18%; p<0.001) and higher rates of myocardial infarction (14% open vs. 8% EVAR; p=0.002), respiratory complications (38% vs. 20%; p<0.001), and acute kidney injury (42% vs. 26%; p<0.001). The overall major adverse event rate was higher after open repair (68% vs. 35%; p<0.001).

Multivariate regression analysis of the propensity-score matched pairs demonstrated that open repair was associated with double the 30-day mortality compared with EVAR (odds ratio 2; 95% CI 1.6–2.7).

Finally, Malas states that all-cause one-year survival was 73% and 59% after EVAR and open repair in the propensity-matched cohort, respectively (p<0.001).

The authors acknowledge some limitations of the study, including the fact that this is a retrospective review of a prospectively maintained database, which is prone to missing data and entry errors.

September 2020 | Issue 87

16 Journal coverage

Aortic Long-term studies

TEVAR outcomes assessed in 10-year study In a single-centre retrospective review of prospectively-collected data, conducted over 10 years, the majority of patients (80%) experienced either sac stability or sac regression after thoracic endovascular aneurysm repair (TEVAR). The study was recently published online in the Journal of Vascular Surgery (JVS).

T

he authors—Adam Tanious (Massachusetts General Hospital, Boston, USA) and colleagues—state that while TEVAR results have been studied in shortterm timeframes, data on longer-term outcomes remain limited. Tanious et al therefore designed the present study to evaluate mid- and long-term outcomes of TEVAR, emphasising postoperative aortic remodelling and the need for reintervention.

Tanious and colleagues conducted an institutional retrospective review of TEVAR for isolated descending thoracic aortic aneurysms (DTAA) conducted in the period 2004–2018.

Primary outcomes studied include aneurysm sac remodelling, freedom from reintervention, and all-cause mortality.

Other outcomes studied include endoleak rates, neurologic complication rates, and any overall postoperative complication rates.

The authors report in JVS that—of 219 patients who underwent TEVAR for DTAA during the study period— the median effect of TEVAR on sac diameter was a 0.7cm decrease in size (interquartile range [IQR] -1.4–0cm).

They add that 80% of patients (n=147) experienced aneurysm sac regression/ stability over the study period and that perioperative neurologic complications occurred in 16% (n=34) of patients.

Tanious and colleagues write that significant predictors of sac growth were endoleak (odds ratio [OR] 65, p<0.001), preoperative carotid-subclavian-bypass (OR 8, p=0.003), and graft oversizing <20% (OR=15, p=0.46). “Every 1mm increase in aortic diameter at the proximal TEVAR landing zone led to increased odds of endoleak (OR 2, p=0.049),” they detail.

Access complications (OR=8) and subclavian artery coverage (OR=6) significantly increased the odds of reintervention, whereas every percentage of graft oversizing protected against reintervention (OR=0.005).

Life-table analysis revealed an overall survival of 78% (71–83%) at median follow-up. At three years, survival was 88% (80–93%) for those with aneurysm sac stability/regression, while it was 70% (49–84%) for those with aneurysm sac growth (p=0.0402).

Finally, a Cox proportional-hazards model showed that the only protective

Study concludes open surgical repair of chronic TBAD “remains highly relevant” In a 10-year study of surgical results of descending aorta aneurysm repair following chronic aortic dissection (TBAD), researchers found that open surgical repair (OSR) showed good early and mid- to long-term outcomes, with “acceptably low” complication rates. The study was recently published online in the Journal of Vascular Surgery (JVS).

THE AUTHORS, JUN WOO CHO (CATHOLIC University of Daegu, Daegu, South Korea) and colleagues, add that OSR for descending aortic aneurysm after chronic aortic dissection associated with Marfan syndrome also showed good early and mid- to long-term outcomes.

Cho et al detail that patients presenting with descending aortic aneurysms developing after aortic dissection often undergo continued aortic expansion, which may require operative interventions to address

factor for mortality was percent oversizing, with every 1% of oversizing having a hazard ratio of <0.001 (p=0.032). This was counter-balanced by the fact that patients with graft oversizing >30% had an increased odds of mortality with a hazard ratio (HR) greater than 10 (p=0.049).

Other significant factors that increased the odds of mortality included endoleak (HR 3.6, p=0.033), diabetes (HR 4.1, p=0.048), age (every one-year increase in age, HR 1.2, p=0.002), year of surgery (every year subsequent to 2004, HR 1.3, p=0.012), and peripheral arterial disease (HR 5.2, p=0.041).

“What distinguishes these results is our focus on midterm follow-up regarding aneurysm sac morphology post stenting,” Tanious and colleagues write in the discussion of their findings, acknowledging five-year results from the Gore TAG device, which they remark showed very similar rates of aneurysm sac change, with 19% experiencing sac growth and 81% having aneurysm sac

Eighty per cent of patients experienced aneurysm sac regression/stability over the study period.”

the risk of aortic rupture. In this study, the authors sought to analyse their experience with OSR of aneurysms of the descending aortic following aortic dissection.

Considering recent advances in various treatment options, the authors remark that thoracic endovascular aortic repair (TEVAR) is “rapidly gaining acceptance” as a treatment alternative to open surgery for acute complicated type B dissection.

However, they add that the best option between TEVAR and optimal medical treatment is unresolved.

In this single-centre, retrospective cohort study, Cho and colleagues analysed patients who underwent open repair for aneurysmal changes of the descending aorta after chronic dissection, taking into account 30-day operative mortality rate, midterm survival, and major complications. They divided patients into two categories: primary chronic type B aortic dissection and remnant repaired type A aortic dissection (RTAAD).

The authors write that there were 149 patients with enlargement of the descending thoracic aorta developing after aortic dissection, of which 49 had medical management and 100 received OSR. These patients were included in the analysis.

Writing in JVS, Cho et al detail that the 30-day mortality and permanent paraplegia rates were 9%

regression/stability.

Comparing their results to the Gore study, Tanious et al comment: “With more than double the patient cohort, we were able to show nearly identical rates of growth versus stability (20% vs. 40%). Furthermore, we were able to ascribe a mortality benefit to positive aortic remodelling after intervention.

Specifically, we show an 18% increased survival for patients with positive aortic remodelling after TEVAR.” Writing in JVS, the authors acknowledge that the study is limited by the retrospective nature of the analysis and relatively small sample size compared to larger national/ multinational databases.

In addition, all operations were performed at a high-volume, tertiary care aortic referral centre with considerable experience in thoracic aneurysm repair, which “may limit the generalisability of the findings,” they write.

Finally, all oversizing measurements were done in a retrospective matter, and could have differed from the originally intended oversizing of the operating surgeon. They comment: “While our data did show that endoleaks are predictive of aneurysm sac growth and long-term mortality, due to our small sample size were are unable to specify what types of endoleaks have the greatest impact on patients in follow-up.”

The authors conclude that TEVAR “offers a clear survival advantage,” but end with a word of warning: “Rigorous surveillance is necessary to prevent future aortic events through reintervention.”

and 4%, respectively. The one-, three-, and fiveyear survival rates were 83%, 80.9%, and 76.1%, respectively. The one- and five-year survival rates between the primary chronic type B aortic dissection and remnant RTAAD groups showed no significant between-group differences at 86.7% and 84.4%, and 80% and 71.3%, respectively (p=0.289).

In addition, they report that the overall outcomes of other complications such as renal injury, bleeding reoperation, and extracorporeal membrane oxygenation support showed no significant between-group differences, including an insignificantly higher neurological complication rate in the remnant RTAAD group. The survival rate with Marfan syndrome was significantly higher than in patients without Marfan syndrome (p=0.033).

Addressing the limitations of their study, Cho and colleagues acknowledge its retrospective nature, the potential for biases relating to the nonrandomised design of the study, and the small volume of patients assessed.

“A larger patient cohort and longer follow-up evaluation effectuated through a multiinstitutional study may provide a larger database for more powerful statistical analysis,” they posit.

In the context of “widespread availability of endovascular options,” Cho et al assert that open repair in this scenario “remains highly relevant”.

“The best option between TEVAR and optimal medical treatment is unresolved”

September 2020 | Issue 87

18 Journal coverage

Peripheral Recent studies

High level of heterogeneity found in randomised PAD trial antithrombotic regimens

A recent systematic review showed that randomised trials comparing different types of peripheral endovascular arterial intervention have a high level of heterogeneity in their antithrombotic regimens. It also revealed an increasing trend for use of dual antiplatelet therapy post intervention with no clear justification.

AUTHORS MAHIM I QURESHI (North Bristol NHS Trust and University of Bristol, Bristol, UK) and colleagues comment that this finding demonstrates a lack of standardisation and poor reporting of antithrombotic therapy in randomised controlled trials of endovascular intervention.

Writing in the July issue of the European Journal of Vascular and Endovascular Surgery (EJVES), they remark that antiplatelet therapy needs to be standardised in trials comparing endovascular technologies in order to reduce potential confounding.

Exploring this potential for confounding, they remark that dual antiplatelet therapy increases the major bleeding risk, which may contribute to late mortality if regimens were continued long term. “This is especially relevant in the current climate,” they comment, highlighting that the trials included in this systematic review contributed to the late mortality results attributed to paclitaxel.

Qureshi and colleagues say that while randomised trials of new devices for peripheral arterial endovascular intervention are published

regularly, the evidence for which antiplatelet and/or anticoagulant (antithrombotic) therapy to use after an intervention is lacking.

The aim of this systematic review, therefore, was to examine the antithrombotic regimens in randomised trials for peripheral arterial endovascular intervention to understand choices made and trends with time or type of device.

Qureshi et al sourced information from the Medline, Embase, and Cochrane Library databases.

They included randomised trials involving participants with peripheral arterial

Regional anaesthesia alone is reasonable for major lower extremity amputation in highrisk patients, study finds A recent study, published online on 3 August in the European Journal of Vascular and Endovascular Surgery (EJVES), found that regional anaesthesia alone is reasonable for major lower extremity amputation (LEAMP) in high-risk patients, and may initiate a more efficacious enhanced recovery programme than general anaesthesia.

F

irst author Michael R Hall, senior author Katharine McGinigle (The University of North Carolina at Chapel Hill, Chapel Hill, USA) and colleagues detail that there was no difference in outcomes between regional or general anaesthesia techniques in patients undergoing LEAMP, but add that further studies are needed to establish best practices.

Hall et al emphasise the fact that major limb amputations are psychologically stressful and subject patients to perioperative cardiovascular risk. They note that up to 90% of major LEAMP are being performed under general anaesthesia, despite the fact that regional anaesthesia is an acceptable option in most cases.

The authors state that obtaining

a better understanding of who would benefit from regional versus general anaesthesia could reduce complications and Katharine help to establish McGinigle best evidencebased practice.

Hall and colleagues used the Vascular Quality Initiative (VQI) lower extremity amputation module to identify patients aged 18 or over who underwent LEAMP from 2013 to 2018.

They note that outcomes included 30day incidence of major adverse cardiac events (MACE) and all-cause mortality.

Writing in EJVES, Hall et al detail

29% trials

had complete periprocedural antithrombotic protocols and

34% had

complete post-procedural protocols

disease (PAD) undergoing any endovascular arterial intervention.

The investigators assessed trial methods to determine whether an antithrombotic protocol had been specified, its completeness, and the agent(s) prescribed.

They classed antithrombotic therapy protocols as periprocedural, immediate post-procedural (up to 30 days following intervention), and maintenance postprocedural (therapy continuing beyond 30 days).

Qureshi and colleagues included 94 trials in the narrative synthesis. They note that study quality was low and that none of the trials justified their therapy protocol. Only 29% had complete periprocedural antithrombotic protocols, and 34% had complete postprocedural protocols.

The authors report in EJVES that antiplatelet monotherapy and unfractionated heparin were the most common regimen choices in the periprocedural setting, and dual antiplatelet therapy (55%) was most commonly utilised post procedure.

They write that over time there has been an increasing tendency to use dual therapy (p<0.001), which corresponds with the introduction of newer technologies and trials focused on below-the-knee interventions.

Qureshi et al’s results show that periprocedurally, aspirin remains the most widely adopted antiplatelet monotherapy, despite randomised evidence favouring clopidogrel. They note that reasons for this were unclear, but speculate that cost may be a factor as clopidogrel has only relatively recently come off patent. “There is the potential to reduce cardiovascular events periprocedurally by using clopidogrel in future trials,” they add.

that the final sample included 5,567 patients (median age: 65 years; 67% white, 65% male). They report that only 719 patients, representing 13% of the cohort, received regional anaesthesia.

In addition, compared with patients undergoing general anaesthesia, patients in the regional group were older (67 vs.

65 years; p<0.001) and more likely to have diabetes (78% vs. 69%; p<0.001), end stage renal disease (26% vs. 18%; p<0.001), congestive heart failure (33% vs. 27%; p<0.01), and coronary artery disease (35% vs. 30%; p<0.01).

Hall and colleagues add that the overall incidence of MACE, death, and MACE or death was 5%, 6%, and 9%, respectively. In addition, there was no statistically significant difference by anaesthesia groups for MACE (odds ratio [OR] 0.98, 95% CI 0.69–1.39) or mortality (hazard ratio [HR] 1.03, 95% confidence interval [CI] 0.9–1.17).

According to Hall et al, this is the largest retrospective study analysing the outcomes for LEAMP using either regional or general anaesthesia. They note that other research using the National Surgical Quality Improvement Program (NSQIP) database demonstrated similar results, namely no difference in 30-day mortality or cardiac events, but was limited to above-knee amputations only and the majority of the regional anaesthesia used was spinal anaesthesia. “The present results parallel these studies while including

regional nerve block techniques as well as all major LEAMP in the analysis,” they comment, which they add suggests acceptable short-term outcomes for all types of regional anaesthesia.

The authors recognise that physiological stress during and immediately after the major LEAMP operation may drive the postoperative outcomes regardless of anaesthetic

These findings offer a critical insight into this highly complex, highly comorbid, and understudied population.”

approach and state that further study is warranted to determine whether regional anaesthesia can attenuate that stress by reducing the pain response during and after surgery.

They conclude: “The VQI represents a ‘real-world’ data source that provides a view of current outcomes in a large population of patients undergoing elective limb amputation,” adding that these findings “offer a critical insight into this highly complex, highly comorbid, and understudied population”.

September 2020 | Issue 87

20 Interview

Profile

Roberto Chiesa

From his early days in cardiac surgery through to his professorship in Milan, Italy, Roberto Chiesa talks to Vascular News about various aspects of his career so far. He stresses the importance of being skilled in both open and endovascular techniques, reflects on his proudest professional moments, and discusses his current areas of research. A specialist in the treatment of thoracic and thoracoabdominal aortic disease, Chiesa is an executive board member of the inaugural CX Aortic Vienna meeting (8–11 September, virtual), and here details what is in store for delegates.

What led you to pursue a career in vascular surgery?

When I was a young medical student, I fell in love with transplants. In particular, I was struck by the first heart transplantation performed by Christiaan Barnard in 1967 and I decided to enter the world of cardiovascular surgery. The first part of my professional life was spent in the cardiac surgery departments directed by Magdi Yacoub; with him I performed heart and lung transplantations for two years.

Who have been your professional mentors, and what lessons did you learn from them?

The first: Vittorio Staudacher, director of the emergency surgery department at Policlinico di Milano Hospital and Milano University. The second, Edmondo Malan, the first to introduce vascular surgery in Italy. Other mentors are: Jean Michel Dubernard, the first surgeon to perform combined kidney-pancreas transplantation in Europe, and Edouard Kieffer, who was the king of vascular surgery in France. And last but not least, Jo Coselli, who is a good friend in addition to being a mentor, and taught me to perform thoracoabdominal aortic surgery.

How have you seen the vascular field develop over the course of your career?

What I was used to seeing when my career started is completely different to what I see now, 50 years later. The most incredible change was the advent of endovascular techniques and their spread during the beginning of this century. Now, I can offer a chance to a large number of patients who would have been considered unfit for surgery in the past.

Also, some paradigms of treatment have completely changed, including acute type B dissection and thoracic aorta trauma. We were used to treating these urgent conditions with open surgery, with high operative mortality. Today, the approach is endovascular in almost all cases, with really improved outcomes. But endovascular techniques are not a ‘panacea’, and may have significant complications, especially in the long term. I think that endovascular treatment should be performed only by surgeons who can also offter the open surgical counterpart, which means they can decide impartially what is the best solution for every specific situation.

How do you anticipate the field might change in the next decade, and what developments would you most like to see realised?

Certainly, endovascular techniques will continue to evolve, and will obtain even better results for an increasing number of patients. However, I also expect that there will be an upswing in open surgery, in selected situations, and that is why I strongly believe that open surgery must be taught to younger generations. The vascular surgeon of the future will have to know both open and endo solutions for every disease, and be skilled in using and combining them, tailoring their decisions to

patients’ needs. Probably also robotic surgery will enter our field, and its principles should be known by future generations.

In the last year, which new paper presentation has caught your attention?

The article “Spinal cord deficit after 1,114 extent II open thoracoabdominal aortic aneurysm repairs,” published

by Coselli et al last year in the Journal of Thoracic and Cardiovascular Surgery impressed me.

First, because Jo did a wonderful job, operating on more than a thousand of the worst and most extensive thoracoabdominal aortic aneurysms (TAAAs), with good results. Secondly, because it shows that despite all the efforts of the last 50 years, spinal cord ischaemia remains a high risk and a terrible complication.

What has been the proudest moment of your career to date?

When I was elected as president of the French Vascular Surgery Society (SCVE) in 2013, and president of the Italian Vascular Surgery Society (SICVE) in 2015.

We worked hard, with a wonderful group of esteemed collaborators, to improve the participation of young vascular surgeons in the activities of the Societies. One of the changes we made was to increase the number of educational grants for young members. Also, we organised two wonderful national symposia, in Nice for the SCVE in 2013, and in Milan for the SICVE in 2015.

The vascular surgeon of the future will have to know both open and endo solutions for every disease.”

What are your current areas of research?

My main scientific interest has been the surgical treatment of thoracic and thoracoabdominal aortic disease. I became a member of the committee to define the guidelines for thoracocabdominal surgery of the aorta of the SICVE, and member of the writing committee of the descending thoracic aorta clinical practice guidelines of the European Society for Vascular Surgery (ESVS).

Another important objective of my past and current research is the surgical, endovascular, and “hybrid” treatment of diseases that involve the aortic arch, including the ‘frozen elephant trunk’ technique, the ‘arch debranching’ hybrid technique, and the ‘total endo’ arch repair. I was asked to become a member of the committee of experts writing the “Current options and recommendations for the treatment of thoracic aortic pathologies involving the aortic arch: An expert consensus document of the European Association for Cardio-Thoracic Surgery (EACTS) and the European

Society for Vascular Surgery (ESVS)”.

Vascular graft infections, mainly involving thoracic and abdominal aortic grafts and endovascular stent grafts, represent one of my main historical focuses.

I was involved as coordinator of several multicentre studies on arterial homografts for replacement of infected vascular grafts in the treatment of aortooesophageal and aortobronchial fistulae, investigating new surgical techniques and performing a systematic review and meta-analysis of the literature.

I am coordinator and principal investigator of numerous trials involving endovascular devices, especially thoracic and thoracoabdominal aortic stent grafts.

My scientific interest in the last decade has focused in particular on the use of dedicated endovascular systems to treat type B aortic dissection, and to the development and improvement of branched and fenestrated thoracoabdominal aortic stent grafts.

Issue 87 | September 2020

Interview 21

What advice would you give to someone starting their career in vascular surgery?

My advice would be: to attend different high-level vascular surgery centres in order to learn both open and endovascular surgery; to read at least two scientific journals every month; and to pull yourself back together when something goes wrong.

What are the biggest challenges currently facing vascular surgery?

The biggest challenges at the moment are total endovascular aortic arch repair, paraplegia prevention during open and endovascular repair of TAAA, and the treatment of vascular prosthetic infections.

Could you tell us about one of your most memorable cases?

A 27cm thoracoabdominal aneurysm in a 34-year old Marfan patient, treated by open repair with a multi-branched Dacron graft and bypass loop for the intercostal arteries, which had a successful course!

How do you like to spend your time outside of work?

My time outside work is very short! But I like to spend this time with my wife Marina, my son Vittorio, our small dog Liz, driving a Porsche 992 Carrera 4S, cycling for more than 100 km, and jogging three times a week.

What can delegates expect from the inaugural CX Aortic Vienna meeting?

CX Aortic Vienna will be a real rendezvous for all vascular surgeons who want to be updated on new scientific evidence in the aortic field and technical details of aortic surgical procedures from the aortic valve to the iliacs. There will be opinion leaders’ presentations, accompanied by very interactive sessions online, with the possibility to ask questions and participate in polling. Also, technical surgical videos will be presented and discussed. All techniques to treat the aorta will be included, both open and endo.

Fact file Current roles

2007–present: Professor of Vascular Surgery, VitaSalute University School of Medicine, Milan, Italy 1995–present: Head of the Division of Vascular Surgery, IRCCS Ospedale San Raffaele, Milan, Italy

Education

1992: Specialisation in Cardiac Surgery, Siena

University, Siena, Italy 1984: Specialisation in Vascular Surgery, Milan University, Milan, Italy 1979: Specialisation in General Surgery, Milan University 1974: Degree in Medicine and Surgery, Milan University

Editorial roles (selected)

Associate editor of Annals of Vascular Surgery Associate editor of the International Journal of Cardiology

Associate editor of the Italian Journal of Vascular and Endovascular Surgery

Society positons (selected)

2015: President of the Italian Society of Vascular and Endovascular Surgery (SICVE) 2013: President of the French Society of Vascular Surgery 2007–2013: Board member of the French Society of Vascular Surgery (SCVE)

Issue 87 | September 2020

23

Patient-specific computation model may improve AVF maturation rates The results of a randomised controlled trial—the Shunt simulation study—show that a new patient-specific computation model accurately calculated postoperative access flow. As flow is related to maturation, the authors argue that this model may potentially improve arteriovenous fistula (AVF) maturation rates.

A

uthors Niek Zonnebeld (Maastricht University, Maastricht, The Netherlands) and colleagues— on behalf of the Shunt simulation study group— add that further investigation is needed to improve the predictive power of these simulations in order to render the computational model an adjunct to surgical planning.

Writing in the July edition of the European Journal of Vascular and Endovascular Surgery (EJVES), Zonnebeld et al detail that an AVF needs to mature before it becomes suitable to cannulate for haemodialysis treatment, and that maturation depends on postoperative flow increase.

The authors highlight that AVF maturation remains a permanent issue in vascular access surgery for haemodialysis treatment, with 20–40% of AVFs failing to mature. To address this, they developed a patient-specific computational model that predicts immediate postoperative flow, and hypothesised that providing information from this model for planning of fistula creation might reduce failure rates. Zonnebeld and colleagues conducted a multicentre, randomised controlled trial in nine Dutch hospitals, in which they recruited patients with renal failure who were referred for AVF creation. Using 1:1 randomisation, they assigned patients to the control or computer simulation group. Both groups underwent a work up, with physical and duplex ultrasonography (DUS) examination.

In the simulation group, the data from the DUS examination were used for model simulations, and—based on the immediate postoperative flow prediction—the ideal AVF configuration was recommended.

Zonnebeld et al detail that the primary endpoint was AVF maturation defined as an AVF flow ≥500ml/min and a vein diameter of ≥4mm six weeks postoperatively.

The secondary endpoint was model performance (i.e. comparisons between measured and predicted flows, and (multivariable) regression analysis for maturation probability with accompanying area under the receiver operator characteristic curve.

A total of 236 patients were randomly assigned (116 in the control and 120 in the simulation group), of whom 205 (100 and 105, respectively) were analysed for the primary endpoint.

The authors report in EJVES that there was no difference in failure to mature rates between the groups (29% and 32%, respectively). Immediate postoperative flow prediction had an odds ratio [OR] of 1.15 (1.06–

Incorporating the flow predictions in a hybrid model […] might be beneficial.”

2040

1.26; p<0.001) per 100ml/ min for maturation, and the accompanying operator characteristic curve was 0.67 (0.59–0.75).

Zonnebeld and colleagues recognise that the study has several limitations, including the fact that the primary endpoint was not a clinical one; it does not give any information on the functionality/usability of the AVF. However, they stress that it is an objective measure, and when patients reach the criteria of ≥500ml/min and a vein diameter of 4mm, as defined in this study, there is a 95% likelihood that the AVF will become functional.

Furthermore, to assess the vascular access functionality, the included patients should have initiated dialysis treatment. However, it remains very difficult to predict which and when a predialysis patient will progress to dialysis dependency and start haemodialysis. In the latter group of patients clinical AVF functionality cannot be determined.

Despite these limitations, the authors highlight the generalisable nature of their results, due to the fact that most of the (pre-)haemodialysis patients in need of an AVF were eligible for inclusion, and that the study was designed in such a way that it could be implemented easily in daily practice. In addition, DUS protocols were standardised to comply with the model’s demands. Usually, Dutch hospitals have well-equipped vascular laboratories with trained technicians who routinely perform preoperative DUS examination for AVF surgery.

Zonnebeld et al write that the multicentre design of the present study is a “major strength”, as it shows that the model can be implemented in other clinics. In addition, they note that selection of dialysis facilities for the multicentre study ensured a representative sample of the Dutch dialysis population, comparable with other European populations and studies. Compared with North American studies, however, they recognise that there is a considerably lower percentage of blacks included.

The authors summarise that simulating patient-specific immediate postoperative flows is an “innovative approach” to improve AVF maturation. “Since AVF maturation does not depend on blood flow enhancement through the anastomosed vessels exclusively, the predictive power of a single model was found to be insufficient to support clinical decision-making,” they write.

Looking to the future, the Shunt simulation study group speculate that incorporating the flow predictions in a hybrid model, in which other relevant but non-physical parameters or factors can be incorporated, might be beneficial.

Ultrasound-guided PTA is a “valuable tool” to treat vascular access stenosis Routine ultrasound-guided percutaneous transluminal angioplasty (PTA) is a feasible treatment for native arteriovenous fistula (AVF) dysfunction, according to a recent study by Antonio Granata (“Cannizzaro” Hospital, Catania, Italy). The study findings were published online on 25 July in the Journal of Vascular Access (JVA).

%

of AVFs fail to mature

GRANATA ET AL DESCRIBE PTA as the gold standard for patients with vascular access stenosis and aimed to evaluate the efficacy and safety of ultrasound-guided PTA in the treatment of native AVF venous stenosis.

The investigators determined the need for intervention by physical examination and duplex ultrasound in 162 patients. All patients with failing or not maturing AVF were treated in the outpatient setting under ultrasound guidance.

Granata and colleagues evaluated procedural success with repeated post-procedural ultrasound examinations. All procedures were performed under local anaesthesia by a single nephrologist and were performed in a single vascular laboratory, while follow-up ultrasound was performed in the dialysis unit of destination.

Writing in JVA, the authors detail that early technical success was obtained in 95.6% of cases (154 of 162) and complications occurred in 22 patients (13.5%), with no major complication requiring surgical or fluoroscopic endovascular intervention.

In addition, they noted that primary patency at six and 12 months was 84% and 69.8%, respectively. Risk factors for AVF failure/ secondary PTA were vascular access, low blood flow rate, and vintage, as well as the need for thrombolysis during the first PTA. Speaking to Vascular News, the authors comment that the method is particularly indicated in patients who still have residual diuresis.

Issue 87 | September 2020

25

Dialysis access needs to be a priority in the COVID-19 era Panagiotis Kitrou Nicholas Inston Comment & Analysis Panagiotis M Kitrou and Nicholas Inston discuss the impact of the COVID-19 pandemic on vascular access services. Despite the disruption caused, they are optimistic that the pandemic should be viewed as a catalyst for change. It is time to “redesign and restructure” vascular access programmes, they tell Vascular News.

T

he COVID-19 pandemic has resulted in major disruption in the delivery of clinical services on a scale previously unseen. In many countries, rationing of facilities and severely restricted or zero access to operating theatres has been imposed.

It has been estimated that 28.4 million surgical procedures have been cancelled globally, with the highest cancellation rates in benign disease.1 The crisis has affected different countries and even different regions of countries variably. In Asia, 47% of healthcare practices suspended elective vascular surgery completely and 23% scaled down activity.2 In the UK, it has been estimated that to clear the backlog of cancelled surgery at 20% extra activity will require 11 months, even if further surgeries are not factored in.

To manage constrained services, many societies issued prioritisation to allow rationing based on clinical risk, mainly based on estimated urgency and need for treatment. These have been classified as 1a. emergency <24 hours; 1b. urgent (up to 72 hours); 2. up to one month; 3. up to three months; and 4. over three months by the Royal Colleges in the UK,3 and by the Society for Vascular Surgery (SVS) as 1. postpone; 2a. consider postponing; 2b. postpone if possible; and 3. do not postpone.4

Provision of vascular access for dialysis “less than ideal” before pandemic

The impact of COVID-19 on dialysis access is not yet known, but it is predicted that the rates of definitive access have been severely affected.

Prior to the pandemic, the provision of vascular access for dialysis was already identified as being less than ideal. In the USA, 80% of patients initiate dialyses on a central venous catheter (CVC)5 and international rates of definitive access are highly variable.6

Despite this, benefits of definitive vascular access and avoidance of CVCs are clearly demonstrated, particularly in the younger and less comorbid patients.7,8 The problems encountered during the first peak of the pandemic are likely to have resulted in many patients starting dialysis on a CVC. This is multifactorial.

Patients with chronic kidney disease (CKD) stages 4 and 5 require access in preparation for dialysis. These patients who were classed as a vulnerable group have been advised to follow enforced shielding practices. As such, they neither fall into a high priority group for surgery or are advised to attend hospital

is not yet possible to assess whether COVID-19 infection had adverse outcomes. Anecdotally, claims have been made for prothrombotic tendencies, particularly in those severely affected, but data on fistula loss secondary to infection is not yet clear. Dysfunctional access may have been afforded higher priority and performing maintenance procedures may have avoided CVC insertions. It is unclear yet whether patients presented later during the pandemic due to shielding risks, or hospitals operated policies of inserting a CVC to reduce lengthy salvage procedures.

The consequences arising from increased CVC placement and reduced fistula creation and salvage will result in multiple issues. Repeated hospitalisation, bloodstream infections, catheter dysfunction, central venous stenosis, and occlusion are all a product of increased catheter use and as a consequence healthcare costs will increase.9 This significant economic and healthcare burden will not only start to show now, but as renal failure is a chronic disease will have significant effect on health economics in the long term. In addition, CVCs have a negative impact on the quality of life and longevity of haemodialysis patients and constitutes a major deviation from best practice guidelines and a serious setback in the standard of care previously delivered.10

“Robust plans” needed for predicted second wave

Whilst some countries are unfortunately currently dealing with the first wave, others are now preparing for a predicted second wave. The needs of CKD and dialysis patients require robust plans to optimise safe creation, maintenance, and

To manage dialysis access appropriately during peaks of COVID-19 will require better identification of those at need with more timely assessment and creation of access.” appointments in person. Assessment for vascular access generally requires ultrasound mapping and this may have been avoided due to patient concerns and/or clinical policies to avoid virus exposure. For the same patients, preemptive living donor transplantation, which may have avoided the need for vascular access, may have been suspended.

In patients infected with COVID-19, the requirement for renal replacement therapy was high, particularly in those requiring intensive care. The impact of multiple vascular access attempts on these patients and long-term effects on renal function remain to be seen, but may add a further healthcare need.

For patients with existing access data,

salvage of definitive vascular access and avoidance of the use of CVCs. These strategies may require local modifications. Ideally cold (green) sites should be used, although dialysis patients’ inability to isolate due to thrice weekly treatment may prohibit pure “clean” pathways. Risk assessments may need specific “renal pathways” to be developed rather than apply standard surgical risk stratification.

Where surgical services are overwhelmed or resources compromised, other strategies should be considered, particularly endovascular approaches to maintenance, salvage, and even creation using percutaneous devices.

This may increase the availability of additional operators, (e.g. interventional

nephrologists and interventional radiologists) where staff redeployment or sickness is a problem, and also allow procedures to be performed in alternative facilities, avoiding hot sites and potentially freeing up theatres.

In order to recover from the first wave of COVID-19 and prepare for further phases, the provision of the best dialysis access, including peritoneal dialysis, will require close working with the wider multidisciplinary team involved in assessment, creation, cannulation, surveillance, maintenance, and salvage of definitive access.

An opportunity for change in the interest of renal patients

To manage dialysis access appropriately during peaks of COVID-19 will require better identification of those at need with more timely assessment and creation of access.

Early identification of problematic access through skilled clinical examination, timely and appropriate referral for diagnostics, and treatment using optimal technologies and devices by those with expertise should be available. Follow-up and surveillance should be based around dialysis sessions and training of dialysis centre staff to cannulate, examine, and identify problems with liaison and accessibility to expertise made easily available.

The challenges of dialysis access may have been exacerbated by the pandemic, but all these requirements were present before. This is an opportunity for vascular access programmes to redesign and restructure, not only to deal with the pandemic, but to build better programmes suited to the needs of the large global population of renal patients.

Panagiotis M Kitrou is an interventional radiologist at Patras University Hospital, Patras, Greece.

Nicholas Inston is a consultant transplant and vascular access surgeon at the University Hospital Birmingham NHS Trust, Birmingham, UK. References 1. CovidSurg C, Nepogodiev D, Bhangu A. Elective surgery cancellations due to the COVID-19 pandemic: global predictive modelling to inform surgical recovery plans. Br J Surg 2020.

2. Ng JJ, Ho P, Dharmaraj RB, et al. The global impact of COVID-19 on vascular surgical services. J Vasc Surg 2020; 71(6):2182–3 e1.

3. RCS. Clinical guide to surgical prioritisation during the coronoavirus pandemic.

4. SVS. Vascular conditions by category, with Teir Class 2020 [Available from: https://vascular. org/sites/default/files/Vascular%20surgery%20 triage%20by%20Tier%20Class%203.24.20.pdf].

5. USRDS. USRDS 2019 Report 2019 [Available from: https://www.usrds.org/2019/view/USRDS_2019_ ES_final.pdf].

6. Pisoni RL ZL, Port FK, Robinson BM. Trends in US vascular access use, patient preferences, and related practices: an update from the US DOPPS Practice Monitor with international comparisons. Am J Kidney Dis 2015; 65(6):905–915. Am J Kidney Dis 2015; 65:905–15.

7. Ravani P, Quinn R, Oliver M, et al. Examining the association between hemodialysis access type and mortality: the role of access complications. Clin J Am Soc Nephrol 2017; 12(6):955–64.

8. Quinn RR, Oliver MJ, Devoe D, et al. The effect of predialysis fistula attempt on risk of all-cause and access-related death. J Am Soc Nephrol 2017; 28(2):613–20.

9. Vassalotti JA, Jennings WC, Beathard GA, et al.

Fistula first breakthrough initiative: targeting catheter last in fistula first. Semin Dial 2012; 25(3):303–10.

10. Lok CE HT, Lee T, et al. KDOQI vascular access guideline work group. KDOQI clinical practice guideline for vascular access: 2019 update. Am J Kidney Dis 2020; 75(4).

September 2020 | Issue 87

26

Study shows advantages of Ellipsys system in dialysis access creation A new study shows significant benefits of the Ellipsys vascular access system (Avenu Medical) in easily and safely creating durable vascular access for end-stage renal disease (ESRD) patients who require haemodialysis.

ACCORDING TO AN AVENU MEDICAL PRESS release, the system also offers a standardised process for using the minimally invasive technology that other physicians can follow to reproduce the results, which “will make it easier for more practitioners to adopt this patient-friendly approach to dialysis access,” explained lead author Alexandros Mallios, a vascular surgeon at Institut Mutualiste Montsouris of Paris, France.

Published in the Journal of Vascular Surgery (JVS), this marks the largest study of any percutaneous arteriovenous fistula (pAVF) technique to date. Of the 232 patients who had an Ellipsys pAVF created between May 2017 and July 2019, there were no adverse events, and 96% still had fully functioning fistulas with strong blood flow after a year. That patency rate is higher than published rates for surgically created fistulas, which average about 60% after one year.

“Vascular access is quite literally the lifeline for dialysis patients,” said Mallios. “The advantages of the percutaneous Ellipsys fistula are that it is a very safe, simple, and reproducible way to create a fistula that will function for a long time with minimal interventions.”

In addition, the study reported that patients were able to begin using their pAVF for dialysis an average of four weeks after creation, with 6% of fistulas becoming functional (or “mature”) in as little as two weeks. Such rapid maturation can have a significant impact on patient safety, as it avoids the use of a central venous catheter (CVC) if they need to begin dialysis quickly. Compared to fistulas, CVCs are associated with significantly higher rates of complications, including infection and even death.

One of the most important aspects of the study, Mallios added, is that it offers a protocol for fistula

creation, maturation and maintenance—which should make it easier for other physicians to adopt the relatively new procedure. For example, the study shows the benefit of adding a new step to the procedure— performing balloon angioplasty immediately after a fistula is created. That improves blood flow and speeds maturation, and could improve patency rates without increasing the need for additional maintenance procedures.

“Mallios’ results are very exciting, particularly with such a large patient population, as it adds to the

growing body of evidence that this approach offers a safe and effective way to quickly create a functional percutaneous fistula,” says Mark Ritchart, president and CEO of Avenu Medical. “He also uses his valuable experience as a guide to enable more widespread use of percutaneous fistulas, which may improve patient safety by reducing reliance on riskier vascular access options.”

In April, JVS published a case report by Mallios that featured a 3D rendering of the Ellipsys pAVF on the cover of the publication. Mallios also coauthored two recent papers in the Journal of Vascular Access that discussed patient eligibility for Ellipsys and the similarities between an Ellipsys pAVF and a surgical AVF, the current standard of care.

Bluegrass Vascular Technologies has announced the publication of the results of its prospective, multicentre SAVE-US (Surfacer system to facilitate access in venous occlusions—United States) study in the Journal of Vascular Access. The results of this study led to the FDA recently granting de novo classification of the Surfacer system.

T

Of the 232 patients who had an Ellipsys pAVF created between

Vascular access is quite literally the lifeline for dialysis patients.”

Prospective, multicentre SAVE-US results published

he Surfacer Inside-Out access catheter system (Surfacer system) is intended to obtain central venous access to facilitate catheter insertion into the central venous system for patients with upper body venous occlusions or other conditions that preclude central venous access by conventional methods.

The Surfacer system employs a novel Inside-Out approach.

This US Food and Drug Administration

In addition, recently published longterm Ellipsys data showed a functional patency rate of 92% at two years. The study also found high levels of patient satisfaction with the procedure.

Cleared by the FDA in 2018 for patients with endstage kidney disease, Ellipsys is the first significant innovation in AVF creation in over 50 years. It transforms a complex surgery into a minimally invasive procedure that can be performed in a hospital outpatient setting or ambulatory surgery centre. Since 2015, more than 1,800 patients worldwide have had the Ellipsys procedure.

(FDA) approved investigational device exemption (IDE) study was designed to evaluate the performance and safety of the Surfacer system when used to facilitate central venous access in patients with thoracic central venous obstructions.

Thoracic central venous obstruction occurs in roughly 40% of patients where haemodialysis is performed via a central venous catheter. While permanent arteriovenous fistulas are the preferred form of vascular access for haemodialysis

MAY 2017

&

JULY 2019

96% still had fully

functioning fistulas with strong blood flow after a year

patients, central venous catheters continue to serve as an important bridge to securing long-term access for lifesaving haemodialysis treatment. The current approach for most patients with central venous obstructions is to use an alternative vein, which reduces the ability to place and mature a functioning fistula, resulting in increased catheter days and costs. “The SAVE-US study met both its primary safety and effectiveness endpoints while demonstrating the ability to use the Surfacer system to gain central venous access in patients with upper body venous obstructions,”

The Surfacer system provides a potentially lifesaving approach for patients on haemodialysis.”

comments Mahmood Razavi, an interventional radiologist at St Joseph Hospital in Orange, USA, the principal investigator for the SAVE-US study, and lead author for the publication reporting these results. “The Surfacer system provides a potentially life-saving approach for patients on haemodialysis and other therapies where placement of central venous catheters is required for treatment.”

“The publication of the results of the SAVE-US study further adds to the clinical evidence supporting the valuable role the Surfacer system can have in helping to establish central venous access in patients with venous obstructions,” states Gabriele Niederauer, CEO and president of Bluegrass Vascular.

“The findings of this study are consistent with previous reports associated with the use of the Surfacer system, confirming the safety and efficacy associated with the use of the device.” Launch of the Surfacer system in the USA is in progress and first commercial cases were successfully performed in May 2020.

Issue 87 | September 2020

London hospital performs UKfirst WavelinQ endoAVF procedure Barts Health NHS Trust has performed a UK-first operation outside of a trial setting that could reduce mortality and risks of infection in patients with dialysis.

I

nterventional radiologists Ounali Jaffer, Rashid Akhtar, and Rajesh Sivaprakasam of The Royal London Hospital (London, UK) carried out the minimally invasive arteriovenous fistula (AVF) procedure, WavelinQ endoAVF (BD Bard).

Jaffer says: “This new treatment really enhances our techniques in treating those patients with end stage kidney disease.

Avoiding a CVC [central venous catheter] is imperative, and now we have another procedure available to enable timely AVF creation.

This new treatment really enhances our techniques in treating those patients with end stage kidney disease.”

Earlier this year, Robert Jones (University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK) spoke at the 2020 Leipzig Interventional Course (LINC; 28–31 January, Leipzig, Germany) about initial multicentre experience results of the WavelinQ catheter. Concluding that “AV is now endovascular,” Jones reported that results of an EU and Canada post-market study showed 95% functional patency at six months and a limited need for secondary procedures.

“This is the first time that this additional data on the multicentre WavelinQ study has been seen,” Jones began. Endovascular AV fistula (endoAVF) devices—created with the intention of improving fistula outcomes—have performed well in clinical studies. “There are high rates of technical success in terms of creation, higher rates of maturation and patency and low rates of complications. But we have got to bear in mind that these closely monitored clinical trials are not the real world”, Jones commented.

At the University Hospitals

27 Birmingham NHS Foundation Trust, Jones and colleagues carried out a matched comparison of WavelinQ fistulas with surgical fistulas. They had 30 in the WavelinQ arm and 40 in the surgical arm. Patency results showed that WavelinQ fistulas outperformed those created surgically.

“There are only a finite number of options available in creating an AVF, which is the lifeline for the patient.

By extending these options, we can maximise the use of these vessels.

“These are early days, but the innovation is exciting and will hopefully benefit a number of our local population with end-stage kidney disease.”

WavelinQ

Issue 87 | September 2020

Topical issues 29

COVID-19

Dedicated protocol in Bologna vascular unit allowed maintenance of elective activity during emergency COVID-19 phase

151 interventions were performed between 8 March and 8 April 2020, compared to 150 in the same period in 2019 and 177 in the same period in 2018

A dedicated protocol in the Bologna metropolitan vascular surgery unit in Italy allowed for the maintenance of regular elective vascular surgery activity during the emergency phase of the COVID-19 pandemic, with no contamination of patients or physicians, and minimal need for intensive care (IC) resources. This was the conclusion of a study recently published in the July edition of the European Journal of Vascular and Endovascular Surgery (EJVES).

RODOLFO PINI, GIANLUCA Faggioli, Mauro Gargiulo, and their colleagues at the Metropolitan Vascular Surgery Unit of the University of Bologna (Bologna, Italy) analysed their activity from 8 March to 8 April 2020.

This period covered the highest recorded rate of infections from COVID-19 in Emilia-Romagna, the region with the second highest level of documented cases of COVID-19 infections, after Lombardia. During this period, surgical activity was maintained only for acute or elective procedures.

The authors note that the preventive screening protocol consisted of nasopharyngeal swabs (NPS) for all patients and physicians with symptoms and for unprotected contact infected cases, and serological physician evaluations every 15 days. In addition, patients treated in the acute setting were considered theoretically infected and the

necessary protective devices were used.

Pini and colleagues evaluated the number of patients and the possible infection of physicians and compared the number and type of interventions and the need for postoperative IC during this period with those in the same periods in 2018 and 2019.

Writing in EJVES, the authors detail that 151 interventions were performed, of which 34 (32%) were acute/emergency.

The total number of interventions was similar to those performed in the same periods in 2019 and 2018: 150 (33, of which 22% acute/emergency) and 177 (29, 25% acute/emergency), respectively.

Intensive care was necessary after 6% (17% in 2019 and 20% in 2018) of elective operations and 33% (11) of acute/emergency interventions.

Furthermore, none of the patients treated electively were diagnosed with COVID-19 infection during

hospitalisation. Of the 34 patients treated in acute/emergency interventions, five (15%) were diagnosed with COVID-19 infection. It was necessary to screen 14 (47%) vascular surgeons with NPS after contact with infected colleagues, but none for unprotected contact with patients; all were found to be negative on NPS and serological evaluation.

In the discussion of their findings, Pini and colleagues emphasise the benefits of the healthcare system organisation, which “allowed maintenance of selected elective surgery activities: cancer surgery, cardiac surgery and vascular surgery for pathologies with a top priority level, as designated in non-pandemic time, with cessation of most outpatient activities and all venous surgical procedures”.

They add that the metropolitan vascular surgery unit in Bologna was the only one in the region performing elective surgery, accepting patients

US team secures funding to examine impact of COVID-19 on aortic dissection A team at the University of Washington in Seattle, USA, has received a funding award through the Patient-Centered Outcomes Research Institute (PCORI) Eugene Washington Engagement Awards programme to provide a patient-centric approach to those with— and at risk of—aortic dissection.

L

ed by Sherene Shalhub, associate professor of surgery in the institution’s division of vascular surgery, the Aortic Dissection Collaborative also includes patients, researchers, and healthcare providers as partners in patient-centred outcomes research.

The team aims to improve the management of aortic dissection and increase quality of life for people impacted by this condition. To do so, the collaborative is engaging stakeholders to build a research infrastructure focused on patient-centred outcomes. It will feature research training; support and networking among patients, physicians, and researchers with expertise in aortic dissection; research consortia dedicated to aortic dissection; industry stakeholders; and patient advocacy groups.

The main deliverable over the next two years is to create a virtual research network and establish research priorities among the stakeholder group, Shalhub explains. These research priorities will then be used

to guide future research proposals that reflect patientcentred priorities.

Initial PCORI funding began in August last year, with additional funding awarded in May 2020 to enhance the work of the collaborative. “The new enhancement award provides a critical opportunity to expand our current work to include the impacts of the COVID-19 pandemic on people living with or at risk for aortic dissection, such as people affected with Marfan syndrome,

The lack of evidence about how COVID-19 affects aortic dissection patients represents a critical knowledge gap.”

planned for surgery at the vascular surgery unit.

Considering resource utilisation, the authors remark: “Keeping the use of strategic resources such as ICU beds for COVID-19 patients in the pandemic period is a key element; current advances in vascular and endovascular surgery allow a very effective response to this need.”

Pini et al mention some limitations of the study, including the scarce number of procedures included, its retrospective nature, and that the data are not associated with a control group to evaluate the real efficacy of the protocols adopted. They note another “element of reflection” as being the rate of false negative tests, which can lead to spread of the infection despite precautions.

The authors conclude that the work may help planning the activity of other units at different times of contamination.

Loeys-Dietz syndrome, and Vascular Ehlers-Danlos syndrome,” says Shalhub.

As COVID-19 took hold across the world, the patient collaborative members expressed concerns over their potential susceptibility to the novel coronavirus, whether they were at higher risk for adverse outcomes from the virus, and on their ability to access necessary ongoing care related to aortic dissection.

Collaborative participants who represent healthcare providers, research, and advocacy confirmed that the lack of evidence about how COVID-19 affects aortic dissection patients represents a critical knowledge gap. This may negatively affect the aortic dissection community if it remains unaddressed, Shalhub says.

Key areas the team will investigate in the coming months include how COVID-19 is affecting access to ongoing care, including outpatient visits and operations; changes in patterns of care-seeking behaviour for acute symptoms or complications of aortic dissection (e.g., whether patients are withholding visits to the emergency department); and how COVID-19 affects the risk of complications among people with or at risk for aortic dissection.

Starting 3 August, the Aortic Dissection Collaborative plans to disseminate a COVID-19-specific survey for patients, family members, and physicians. This survey adds to continuing support for another designed to capture aortic dissection patient experiences. “Both surveys will form the basis to understand the concerns and experiences of those living with aortic dissection and will guide our next steps in research topic identification and prioritisation,” adds Shalhub.

September 2020 | Issue 87

30 Journal coverage

Venous New data

Compression after radiofrequency ablation of varicose veins “adds no clinical benefit” A randomised controlled trial has found that clinical and patient-reported outcomes following radiofrequency ablation (RFA) of varicose veins with compression are no better than without compression. Madu Onwudike (Manchester University NHS Foundation Trust, Manchester, UK) and colleagues conducted the study, which appeared as an Editor’s Choice paper in the July edition of the European Journal of Vascular and Endovascular Surgery (EJVES).

T

he authors detail that the target vein occlusion rate was not influenced by whether postprocedure compression was worn or not following RFA of varicose veins, where phlebectomies had not been performed adjunctively. Similarly, there was no evidence that quality of life (QoL) scores, patient satisfaction, and complications were inferior in the group that had no post-procedure compression.

Onwudike and colleagues write that post-procedure limb compression, hitherto routine following open varicose vein surgery, has been extended to endovenous procedures. “However,” they comment, “no robust evidence exists to support this practice”. Therefore, the investigators designed the present study to evaluate the clinical and patient-reported outcomes with and without post-procedure leg compression following RFA. They note a few studies that raise doubts about the necessity for post-procedure compression, including a 2017 Annals of Vascular Surgery study by Ayo et al, which compared seven-day compression versus

no compression and reported no difference in clinical (vein obliteration) and patient-reported outcomes (pain, ecchymosis, and QoL) following endovenous ablation. However, Onwudike et al’s study is the first to investigate the role of post-procedure compression where all the veins were exclusively ablated using RFA. In this single-centre, prospective, non-inferiority randomised controlled trial, the investigators recruited adult patients into two groups: A (RFA with compression stockings for two weeks) and B: (RFA alone). The primary outcome was ultrasound determined target vein obliteration at 12 weeks.

Secondary outcome measures included a QoL score (Aberdeen Varicose Vein Severity Score [AVSS] and Revised Venous Clinical Severity Score [RVCSS]), patient satisfaction, pain score, and complications.

In total, the investigators recruited 100 consecutive patients—51 to group A and 49 to group B—classified as clinical class C2–C6 of the Clinical-Etiological-

DOACs show promise over heparin injections in metaanalysis comparing cancerassociated VTE treatments A recent meta-analysis found that direct oral anticoagulants (DOACs) appear to be a “reasonable alternative” to low molecular weight heparin (LMWH) for the treatment of venous thromboembolism (VTE) in cancer patients. The study appeared online on 25 July in The American Journal of Cardiology.

AUTHORS KIRTIPAL BHATIA (Icahn School of Medicine at Mount Sinai, New York, USA) and colleagues write that LMWH is considered the standard anticoagulant therapy for patients with cancer-associated VTE. However, they note that while the efficacy and safety of DOACs in the treatment of VTE in patients without cancer has been validated, their role in cancer-associated VTE is still evolving.

Bhatia et al therefore conducted a meta-analysis of the published randomised controlled trials (RCTs) comparing DOACs with LMWH for the treatment of VTE in cancer patients.

The investigators performed a comprehensive literature search of electronic databases (Embase, Medline, and Cochrane Central) from inception to 30 May 2020 using a predefined

search strategy and included all RCTs comparing DOACs with LMWH in cancer associated VTE. Bhatia and colleagues detail that the principal efficacy outcome was recurrence of VTE, either symptomatic or incidentally discovered. The principal safety outcome was incidence of major bleeding (defined as overt bleeding leading to a decrease in the haemoglobin level of ≥2g/dL, transfusion of two or more units of blood, occurring at a critical site, or fatal bleeding).

They write that secondary outcomes included clinically relevant non-major bleeding (CRNMB) and all-cause mortality. CRNMB was defined as clinically overt bleeding not meeting the criteria for major bleeds, associated with impairment of daily living or requiring medical attention. All outcomes were

Anatomical-Pathophysiological (CEAP) classification.

Onwudike and colleagues write in EJVES that, at 12 weeks, the occlusion rate of the target vein was similar in both groups at 98% (n=47) and 98% (n=45), respectively (p=1). They also report that here was no statistically significant different in mean AVSS: 6 vs. 5 (mean difference -1, 95% confidence interval [CI] -2–3, p=0.57) and mean RVCSS: 3 vs. 4 (mean difference 1, 95% CI -1–2, p=0.46) scores at 12 weeks.

Finally, they observed comparable patient satisfaction scores (p=0.72) and pain score 2 vs. 2 (p=0.92) were achieved in both groups. Two patients in each group developed deep vein thrombosis at two-

Long-term follow-up analysis may give further insight into differences in success rates based on compression therapy use.” week follow-up (p=1 for above the knee and p=1 for below the knee).

The authors summarise: “This trial supports the conclusion that the widely practised use of compression after RFA adds no clinical benefit for the patients.” However, they add that a much larger study, “preferably a multicentre trial,” may be required to confirm their findings.

assessed at six months.

Writing in The American Journal of Cardiology, Bhatia et al state that they included four RCTs with a total of 2,894 patients in the study-level metaanalysis. Of these 2,894 patients, 1,446 received a DOAC and 1,448 received LMWH. Almost all patients had active cancer (98–100%) and were receiving concurrent cancer treatment (57–73%).

Patients with a poor functional status (Eastern Cooperative Oncology Group [ECOG] performance score >2) and those with basal cell or squamous cell skin cancer were excluded.

Bhatia and colleagues report that recurrent VTE at six months was decreased in patients treated with DOACs compared to LMWH (5.2% vs. 8.2%; RR 0.62, 95% CI 0.43–0.91; p=0.01; I2=30%). In addition, CRNMB was higher with DOACs as compared to LMWH (10.3% vs. 6.3%; RR 1.65, 95% CI 1.19–2.28; p=0.002; I2=29%), driven largely by increased gastrointestinal and genitourinary bleeding.

Furthermore, there was no difference between DOACS and LMWH in either major bleeding (4.3% vs. 3.3%; RR 1.31, 95% CI 0.83–2.08; p=0.25; I2=23%) or in all-cause mortality (23.9% vs. 24.2%; RR 0.99, 95% CI 0.83–1.18; p=0.93; I2=37%). The degree of heterogeneity between the studies ranged from low to moderate.

Commenting on the

significance of these results, Bhatia and colleagues write: “Our metaanalysis supports the use of DOACs as an effective alternative to LMWH for the treatment of VTE in patients with cancer.”

They continue: “The pooled analysis of study-level data shows a statistically significant reduction in recurrent VTE at six months with DOACs as compared to LMWH.” However, they acknowledge that this decreased in recurrent VTE occurred at the cost of increased bleeding events, largely driven

by CRNMB, with no different in major bleeding or mortality.

Senior author of the study, Arman Qamar, (NorthShore University Health System, University of Chicago Pritzker School of Medicine, Chicago, USA) shares with Vascular News that DOACS appear to be a “reasonable alternative” to LMWH for the treatment of cancerassociated VTE and should be more frequently prescribed. He also highlights the lower cost and ease of injection of DOACs over LMWH.

Kirtipal Bhatia

Issue 87 | September 2020

Journal news 33

EJVES impact factor increase: Behind the success and looking ahead Florian Dick Martin Björck Comment & Analysis When the 2019 journal impact factors were published earlier this summer, the European Journal of Vascular and Endovascular Surgery (EJVES) scored 5.328, an increase of 46% on the previous year. Here, for Vascular News, editor-in-chief Florian Dick and senior editor Martin Björck explain the reasons behind this success and how it might affect the future of the journal.

V

ascular surgery is a speciality with fast development. New technologies are developing in different fields, and a lot of research is going on. When the journal impact factor is calculated every single article counts; on average, each EJVES paper published in 2017 or 2018 was cited more than five times during 2019. We are very grateful to the authors who decided to submit their best research papers to us,

and for the >400 reviewers who helped us to further improve the quality of those. Every published full length article was reviewed by a mean of 3.7 external reviewers (often more than once) and is managed by at least one editor.

Still, some well-cited papers deserve to be mentioned. Among the ten papers that contributed with most citations to the 2019 journal impact factor, five were European Society for Vascular Surgery

SVS president, JVS editors respond to controversial paper furore Society for Vascular Surgery (SVS) president Ronald L Dalman (Stanford University, Stanford, USA) has pledged that the SVS and its flagship title the Journal of Vascular Surgery (JVS) will “accelerate changes already underway” in order to improve the culture surrounding the specialty, and align with a core set of values that include diversity, inclusion, fairness and equity.

DALMAN WAS COMMENTING IN a statement that followed the furious reaction to a now-retracted paper published in the August issue of JVS entitled, “Prevalence of unprofessional social media content among young vascular surgeons”.

The paper went viral on social media, prompting accusations of sexism as “provocative posing in bikinis/ swimwear” was listed among items of “inappropriate attire” highlighted in the paper. The furore stirred up bled into the mainstream media, with national outlets such as CNN, HuffPost and Forbes drawing reference to the affair and the Twitter hashtag under which it spread: #Medbikini.

Dalman outlined the significant level of dialogue the Society had received from members in the wake of the

(ESVS) clinical practice guidelines. disease (just behind Arteriosclerosis, The ESVS management guidelines Thrombosis, and Vascular Biology for carotid disease contributed with [ATVB]), we foresee that authors of hot the highest number of citations. The scientific papers, including randomised joint European Society of Cardiology controlled trials, will consider publishing (ESC)/ESVS management guidelines their papers in the EJVES. The number of for peripheral arterial disease (PAD), submissions already increased from 847 and the ESVS guidelines on descending in 2016 to 1,206 in 2019, and we may thoracic aortic diseases, diseases reach 1,600 this year, since there of the mesenteric arteries and were >900 submissions during veins, and vascular access the first half of 2020. This The 2019 journal were also among the top of course creates extra impact factor for ten. A common feature work for the editorial EJVES was 5.328, for all these documents team, and results in a is that they attract higher rejection rate. an increase of scientific and clinical We have created other % on the interest not only among mechanisms, however, in vascular surgeons, but order to be able to publish previous year also among professionals not only the top papers, and of many other medical to stay “inclusive”. One such specialities. We tend to publish mechanism is the development few retrospective single-centre series, of the EJVES-Short Reports into the and more multicentre studies, including EJVES-Vascular Forum. registry work developed by the Vascunet We also publish educational articles, collaboration. editorials, and letters in the main journal, We invested a lot of effort in although they have no influence on the improving the layout of the journal, journal impact factor. We do encourage making the dry scientific content more debates and invite our readers to write easily digestible, as well as in promoting letters on controversial hot topics. social media communication. Scientific Becoming the premier scientific journal publishing is a moving target undergoing in our field does not exclude other rapid change. We also embrace important functions. globalisation. A growing proportion of the readers, authors, reviewers, and staff Florian Dick is head of Vascular Surgery members are non-European. at Kantonsspital St Gallen and professor of Vascular Surgery at the University of Looking to the future Bern in Bern, Switzerland.

Since we are now number eight of all surgical journals (just behind the British Martin Björck is professor of Vascular Journal of Surgery) and number eight Surgery at Uppsala University in of all journals in peripheral vascular Uppsala, Sweden.

study’s inclusion in JVS. “We have listened and continue to welcome your feedback and thoughts, particularly from members in the early stages of their career,” he said.

Earlier, JVS editors Peter Gloviczki (Mayo Clinic, Rochester, USA) and Peter Lawrence (University of California, Los Angeles, Los Angeles, USA) had issued a statement explaining the decision to retract the paper and apologising for the “sadness, anger, and disappointment” caused by its appearance.

“Many who have read the article expressed great concerns about the method of data collection, lack of diversity of the authors collecting data, as well as potential bias in the evaluation and the conclusion,” the editors said in their communique.

The SVS is fully dedicated and focused on embracing and supporting the individual and collective efforts of its members in their pursuit of excellence.”

“Although the editors of the JVS believe that the authors of this paper were attempting to advise young vascular surgeons about the risks of social media, the review process failed to identify the errors in the design of the study with regards to conscious and unconscious bias and thus the published paper was interpreted as broadening inequities in surgery.

46

“It also became apparent that the authors did not receive the approval of the Association of Program Directors in Vascular Surgery (APDVS) to use its database in identifying the vascular surgeons in training who were evaluated for their participation in social media. The editors therefore decided there was sufficient rationale to retract the article.”

For his part, Dalman said that the SVS leadership concurred with the decision to retract the publication, agreeing that “there was clear unconscious bias and methodologic flaws in both the paper and the review process.”

In its constitution and bylaws, Dalman went on, the SVS “embraces the core values of diversity, inclusion, fairness and equity. As a professional medical and membership Society, the SVS is fully dedicated and focused on embracing and supporting the individual and collective efforts of its members in their pursuit of excellence. The publication of this paper in the Society’s journal was not aligned with these essential core values and has prompted the SVS to accelerate changes already underway to significantly improve the culture of the JVS, the Society and the specialty.

“Over one year ago the SVS formed a Diversity, Equity and Inclusion Task Force to look at the breadth and scope of SVS and make recommendations to strengthen the Society’s alignment to its core value on diversity, equity, and inclusion.”

Senior author on the study, Alik Farber (Boston University School of Medicine, Boston, USA) took to Twitter to issue his own mea culpa. “As the senior author of the manuscript entitled ‘Prevalence of unprofessional social media content among young vascular surgeons,’ I want to personally apologise to everyone for the pain and negative impact that this paper has caused to so many people,” he wrote.

Issue 87 | September 2020

Market watch 35

Clinical News First patients enrolled in SUPERSURG study of Supera peripheral stent system

ID3 Medical Belgium has announced the first two enrolments in the SUPERSURG study to investigate the safety and efficacy of Abbott’s Supera peripheral stent system versus surgical endarterectomy in treating patients with common femoral artery disease, with and without femoral bifurcation involvement. The physician-initiated, prospective, multicentre, randomised study is set to enrol 286 patients at 13 centres in four European countries (Belgium, Poland, the Netherlands, and the UK).

Patients will be stratified first based on three criteria: obesity, calcification, and femoral bifurcation involvement.

After this stratification, consented patients will be randomised 1:1 to either an open surgical or endovascular arm.

In addition to superior safety and noninferior efficacy of the Supera peripheral stent system arm as primary endpoint, the study will also assess core lab-based angiographical outcomes post common femoral endarterectomy in a subcohort of 40 patients. The principal investigator of the SUPERSURG study is Koen Deloose, head of the Department of Vascular Surgery at AZ Sint Blasius hospital in Dendermonde, Belgium, who performed the first two procedures (one open and one endo) in the trial.

“My enthusiasm about the use of the Supera peripheral stent system in the common femoral area was initiated by some case experiences at high risk for surgery with great longer-term follow-up,” comments Deloose in ID3 Medical’s announcement.

“Based on these findings, we set up the physician-initiated, single-arm VMI-CFA trial,” Deloose continues.

“The 12- and 24-month outcomes of this 100-patient cohort, presented at VIVA 2019, confirmed our initial enthusiasm, with core lab-based primary patencies of 95% and 93%, respectively, and freedom from target lesion revascularisation (TLR) of 98% at two years (in press). As these results were very close to our surgical data, but with lower complication rates, the idea for a head-to-head randomisation between both treatment strategies, with the same stringent assessment methods, was born. With a support grant from Abbott Vascular, we were able to launch this exciting project.”

Looking to the future, Deloose concludes: “Based on the outcome of this trial, I hope to be able to define subgroups of patients who are better treated with surgery, others with a minimally invasive Supera peripheral stent system implantation. I am convinced that there will be a place for both complementary strategies in the vascular future.”

First sirolimus DEB patient enrolled in Japanese Selution SLR study

MedAlliance’s partner in Japan, MDK Medical, has enrolled the first patient in the clinical study of its novel sirolimus drug-eluting balloon (DEB), Selution sustained limus release (SLR), for the treatment of peripheral arterial disease (PAD). This follows the acceptance of a Clinical Trial Notification (CTN) by Japan’s Pharmaceutical and Medical Device Agency (PMDA).

The study involves up to 132 patients across a number of centres in Japan.

Its objective is to assess the safety and efficacy of Selution SLR for the treatment of lesions of superficial femoral arteries and/or popliteal arteries.

The study is a prospective, controlled, multicentre, open, single-arm clinical investigation. Its primary endpoint will be the primary patency rate at twelve months. Secondary endpoints will include major adverse events/target lesion revascularisation (TLR), primary patency, and the change of Rutherford classification/ankle brachial index (ABI)/walking impairment questionnaire (WIQ).

“We are extremely pleased with the regulatory and quality expertise demonstrated by our partner MDK, and particularly proud that Japanese patients can now benefit from our unique technology. This is the first sirolimus drug-eluting balloon implanted in Japan, where the current paclitaxel-coated balloon market generates more than US$100M in revenue”, commented MedAlliance chairman and CEO Jeffrey B Jump.

In February 2019, MedAlliance became the first DEB company in the world to receive breakthrough device designation status for a sirolimus DEB from the US Food and Drug Administration (FDA). Selution SLR has now achieved three separate FDA breakthrough device designations: for the treatment of AV fistulas; coronary in-stent restenosis, and peripheral below-the-knee lesions. The company announced the enrolment of the first patient in its FDA IDE pivotal coronary trial earlier this month.

In February 2020, MedAlliance announced the award of its first CE mark approval: for Selution SLR in the treatment of PAD. In May 2020, the company announced the award of its second CE mark: Selution SLR 014 PTCA for the treatment of coronary artery disease.

Third-generation Anaconda endograft indicates “satisfactory” aneurysm exclusion at five years The third-generation Anaconda endograft (Terumo Aortic) provides “high technical success” and “satisfactory” five-year

aneurysm exclusion and clinical success rates, a French multicentre prospective observational study (EPI-ANA-01) has found. The investigators note that longer-term results with new generation endografts are “essential” due to a significant decrease in aneurysmrelated survival observed in long-term follow-up after infrarenal endovascular aneurysm repair (EVAR) compared with open repair.

A total of 176 consecutive unruptured infrarenal abdominal aortic aneurysms between June 2012 and October 2013 were included in the study (160 male patients, mean age 75.3±8.4 years). Survival, freedom from type Ia endoleak, limb events, and reinterventions were estimated using the Kaplan–Meier method, and anatomical and clinical characteristics were compared according to the occurrence

Anaconda endograft (Terumo Aortic)

of migration, conversion, adverse limb events, endoleak, and sac enlargement.

The findings, which were published

by Dominique Midy et al in the European Journal of Vascular and Endovascular Surgery (EJVES), showed primary technical success was 98.3% and clinical success was 94.9%. A hostile neck was identified in 33.9% of patients and 10.7% were treated outside the instructions for use (IFU).

An early postoperative (≤30 days) mortality rate of 1.7% was observed.

At one and five years, respectively, the overall survival rate was 94.9% and 65.9% (aneurysm related in four patients [2.3%]) and the clinical success rate was 90.9% and 70.6%. Secondary interventions were performed in 35 of 176 patients (19.9%). The overall limb occlusion rate was 7.9% and the aneurysm sac diameter decreased significantly (preoperative diameter 53.9±8.6mm vs. 42.3±14.7mm at five years; p<0.001). Patients treated outside the IFU had significantly higher rates of migration, surgical conversion, and aneurysm sac expansion (p=0.03).

The investigators also stress that implantation outside the IFU “should be avoided” as it leads to “significantly worse outcomes,” adding that “caution over the risk of limb occlusion and distal embolisation should be observed.”

EffPac trial confirms benefit and safety of paclitaxelcoated balloon catheter

It was recently announced that in the EffPac trial, designed to compare a drug-

coated balloon with an uncoated balloon in the treatment of vascular occlusion in the femoropopliteal region, the drugcoated device proved to be superior.

Additionally, the complete review of the study cohort two years after the intervention showed no increased mortality with the drug-coated balloon.

In cooperation with the Center for Clinical Studies, radiologists at Jena University Hospital, Jena, Germany, initiated an investigation to evaluate the efficiency of the Luminor paclitaxel drug-coated balloon catheter (iVascular) versus an uncoated balloon.

The success of the treatment was measured by the patient’s ability to walk and by ultrasound examinations of the vascular permeability in two followup examinations. This prospective, multicentre, randomised controlled trial enrolled a total of 171 participants at 11 centres throughout Germany.

In a Jena University Hospital press release, principal investigator of the EffPac trial Ulf Teichgräber (Jena University Hospital) summarises the result: “Compared to the control group, in the group treated with drug-coated balloon catheters, there was better vascular permeability and less tissue formation at the former constriction two years after the procedure.”

On behalf of the Federal Institute for Drugs and Medical Devices (BfArM) in Germany, the study authors rechecked the complete cohort with respect to morbidity and mortality. The reason for this was a meta-analysis of angioplasty studies published last year that warned of long-term increased mortality associated with paclitaxelcoated devices. This warning triggered discussions amongst experts, since subsequent analyses of patient-level data could not confirm the increased longterm risk.

According to the Jena University Hospital press release, a possible source of error in determining mortality rates is not considering patients who have not completed the entire followup programme. “Within the trials considered in the meta-analysis, these patients counted up to a quarter of the subjects. Their data are not included in the study result as if they had not participated at all. However, for mortality assessment, they have to be included,” the press release reads.

“This happened for the first time in the EffPac trial,” the announcement continues, detalling that “in the subsequent review of the results, 167 patients were recorded, which represents almost the entire study cohort, thus preventing a misjudgement in comparing the groups.

The review yielded no difference in the survival after two years between the two groups. Teichgräber comments: “The mortality risk by drug-coated balloons turned out to be even lower than that shown in the original two-year results recently published. We could confirm angioplasty with paclitaxelcoated balloons to be a long-term successful and safe treatment option for intermittent claudication.”

Issue 87 | September 2020

Market watch 37

Product News

Celt arterial closure device (Vasorum)

Veryan Medical will support Vasorum in US commercialisation of Celt arterial closure device

Vasorum and Veryan Medical have announced that Veryan Medical will support Vasorum in the commercialisation of the Celt arterial closure device (ACD) in the USA. According to a press release, the Celt ACD has been used in more than 60,000 patients so far, with excellent clinical results following percutaneous catheterbased vascular procedures.

Vasorum co-founder and CEO James Coleman said, “The Veryan Medical agreement is validation that the Celt ACD has proven itself to be a leading arterial closure device that allows rapid and complete haemostasis independent of vascular anatomy, including calcified arteries. This agreement provides an opportunity to accelerate growth for both companies in the USA.” “We are pleased to be working with Vasorum and the Celt ACD, which has proven to be a game changing closure technology” said Nick Yeo, Veryan Medical’s CEO. “We plan to include the Celt device as an option in our MIMICS-3D USA registry, which will start enrolling later this year.

MIMICS-3D USA is a prospective, multicentre observational study evaluating the safety, effectiveness, and device performance of the BioMimics 3D vascular stent system within a real-world clinical population of patients undergoing femoropopliteal intervention.”

He continued: “MIMICS-3D USA will enrol more than 500 patients in 40 clinical sites across the USA and Veryan will conduct a subanalysis of patients who have had a Celt ACD used in the index procedure. Veryan is proud to support innovators like Vasorum to provide insights, marketing strategy, and a top-tier salesforce to ensure commercial success and clinical adoption. The Celt ACD and Veryan’s novel BioMimics 3D stent together represent an exciting combination both for our sales team and our customers.”

Syed Hussain, chairman of Vascular

& Endovascular Surgery at the Christie Clinic in Champaign, USA commented, “I have been using the Celt ACD for several years and have completed over 1,000 implants. The device is extremely easy to use and has unique benefits including rapid haemostasis, allowing for safe patient ambulation shortly after the procedure.”

Alto abdominal stent graft system granted CE mark, launched in the USA

Endologix recently announced that it has received a CE mark for the Alto abdominal stent graft system. This followed an announcement of the first commercial implant and the US commercial release of the recently US Food and Drug Administration (FDA)approved device.

“We are very excited to receive a CE mark for the Alto system, that has been achieved through a strong partnership and collaboration with our European notified body, NSAI” commented Matt Thompson, chief medical officer of Endologix. “Alto will provide our physician partners and patients in the EU with a differentiated lowprofile endovascular treatment option designed to improve durability over traditional endovascular aneurysm repair (EVAR). In addition, with Alto, we anticipate observing improved shortterm outcomes relative to the Ovation iX abdominal stent graft system as a result of the design and manufacturing changes incorporated into Alto. Lastly, CE mark of the Alto system is yet another critical milestone for Endologix as we seek to introduce a portfolio of devices to address the current unmet

needs of EVAR.” “Alto offers a highly differentiated endovascular treatment option to abdominal aortic aneurysm (AAA) patients and includes design features that we believe will enhance ease-of-use, improve acute outcomes, and preserve the long-term durability associated with patient-specific, anatomically adaptive sealing,” commented John Onopchenko, chief executive officer of Endologix.

“We believe Alto, with its ultra-low profile and 7mm aortic neck length indication, will provide patients and physicians with an endograft capable of treating the highest proportion of patients within the indications for use of the device. As we continue with the global roll-out of the Alto system, Endologix is committed to investing in the highest levels of clinical evidence by initiating a head-to-head randomised controlled trial versus traditional undifferentiated EVAR grafts, with the intent of proving the superiority of Alto.

Finally, with our recent announcement regarding our proposed transition to a private company, we are poised to meet the needs of our customers and the patients we proudly serve and fulfil our company mission.”

Surmodics receives FDA 510(k) clearance for Sublime radial access 0.014 RX PTA dilatation catheter

Surmodics recently announced it has received US Food and Drug Administration (FDA) 510(k) clearance for its Sublime radial access 0.014 rapid exchange (RX) percutaneous transluminal angioplasty (PTA) dilatation catheter.

According to a press release, the Sublime radial access 0.014 RX PTA catheter allows below-the-knee access through a transradial approach by providing the longest working length (250cm) on the market. Outer balloon diameters range from 2–4mm with balloon lengths between 20mm and 220mm. The product joins the previously cleared Sublime radial guide sheath within the company’s Sublime radial access platform and is designed to facilitate radial access for the treatment of above- or below-the-knee arteries.

“FDA 510(k) approval of the Sublime radial access 0.014 RX PTA dilation catheter is another step forward in our strategy to become a provider of wholeproduct vascular solutions through the design, development, and manufacturing of highly differentiated products,” said Gary Maharaj, Surmodics president and CEO. “The continued expansion of our Sublime radial access platform

Alto abdominal stent graft system (Endologix)

demonstrates our commitment to developing the transradial peripheral market space through the introduction of longer, lower-profile devices that fill unmet physician and patient needs.”

Radial access offers many benefits relative to femoral access, including reduced puncture site bleeding complications, earlier ambulation, reduced length of hospital stay, and lower healthcare costs. Although transradial access has become a mainstream technique in percutaneous coronary interventions (PCI), it has been less widely adopted in peripheral interventions due to the limited availability of purpose-designed access and therapeutic devices.

The Sublime 0.014 RX PTA dilatation catheter is compatible with a 5Fr guide sheath and is designed to provide the performance of an over-the-wire PTA catheter in an RX platform. Its proprietary reinforced shaft technology with flexible, kink-resistant construction and a tapered RX port transition are designed for optimal trackability and push through distal tortuosity.

Dynetic-35 iliac stent system gains CE mark

Dynetic-35, the balloon-expandable cobalt chromium iliac stent system from Biotronik, is now commercially available in Europe. Indicated for the treatment of de novo or restenotic lesions in the iliac arteries, the product is approved for use in Europe and other markets that recognise CE mark certification.

The Dynetic-35 stent size matrix is 6F compatible, including stent diameters of 5–10mm and lengths of 18–78mm, and comes in working lengths of 90, 130, and 170cm, the largest range of iliac stent sizes on the market, according to a company press release. Biotronik claim that the thin-strut stent combined with the low crossing profile of the balloon catheter delivery system enhances deliverability.

“The new Dynetic-35 is a true improvement over the previousgeneration stainless steel iliac stent. The flexibility, lower profile, and improved deliverability allow direct stenting even in more challenging lesions,” says Michael Lichtenberg (Arnsberg Vascular Center, Arnsberg, Germany). “In my clinical experience with the new stent system, I have been impressed by the smooth placement and deployment for a direct stenting approach, as well as the radial strength of the stent.”

With the 170cm catheter length option, the Dynetic-35 system also enables a radial access approach. “In my practice, I often have the need to use radial access to treat iliac artery disease, which provides more patient comfort and earlier ambulation,” explains Mercedes Guerra-Requena (Guadalajara Hospital, Guadalajara, Spain). “Until now, available options for a radial approach have been limited.

Fortunately, the new Dynetic-35 stent’s 170cm length delivery system option and 6F sheath compatibility enables me to comfortably use a radial approach.”

September 2020 | Issue 87

38 Market watch

Penumbra augments vascular franchise with newly appointed chief medical/ scientific officers

Industry News

Artio Medical acquires Flow Forward Medical, expanding their peripheral vascular portfolio

Artio Medical recently announced it has acquired Flow Forward Medical, a medical device company developing methods for establishing and maintaining vascular access sites.

This stock-for-stock merger transaction in which Flow Forward merged with and into Artio was approved by the Board of Directors and stockholders of both companies. The transaction closed on 8 June 2020.

“Flow Forward’s venous dilation technology is highly complementary to Artio’s existing peripheral vascular portfolio, with significant overlap in physician call points and procedures,” commented F Nicholas Franano, president and CEO of Artio Medical.

“This acquisition provides a unique opportunity to diversify Artio’s

endovascular pipeline, which will now include next generation vascular access solutions for kidney failure patients.”

Studies suggest baseline vein diameter may play an important role in achieving and maintaining routine, reliable AVF use. Flow Forward’s Arteriovenous Fistula Eligibility (AFE) system stimulates flow-mediated vein dilation to expand the initial vein diameter prior to the creation of an AVF. This aims to increase the number of haemodialysis patients eligible for AVF and to enhance the usability and lifespan of newly created AVFs. “Creating and maintaining reliable access sites is a complex vascular challenge, often resulting in complications, repeat procedures, and increased cost to patients, yet is critical for lifesaving haemodialysis treatment,” commented Paul Muller, chief technology officer and general manager of Flow Forward. “We are very excited Artio recognises the significant potential of our technology and we look forward to leveraging their expertise as we prepare for our first clinical use in the coming months and then move toward commercialisation.”

Penumbra has announced the appointment of interventional radiologist Corey L Teigen (formerly Sanford Health, Fargo, USA) as chief scientific officer, and interventional radiologist James Benenati (formerly Miami Cardiac & Vascular Institute, Baptist Hospital, Miami, USA) as chief medical officer. Both positions have been newly created.

Teigen joins immediately as CSO and will contribute his extensive scientific and clinical expertise to ongoing and future research and development efforts.

“In my radiology practice, I have seen first-hand the challenges medical practitioners face while treating difficult medical conditions,” Teigen states.

“At Penumbra, I have a profound opportunity to change the course of healthcare delivery for people living with vascular disease. I feel privileged to join Penumbra’s unparalleled group of talented engineers and leaders, and I look forward to contributing my scientific knowledge to help solve challenging medical problems.”

Benenati will join Penumbra on 1 September 2020 as CMO, and will contribute to clinical and medical affairs strategies and advise upon global commercialisation and market

development activities.

“I am excited to join Penumbra at this very important time for the company, where it is poised for growth, as it moves into the next generation of intelligent clot removal and expands into rehabilitation with the recent launch of the REAL system,” Benenati says.

“Penumbra has changed the landscape of healthcare by providing truly innovative solutions for a wide realm of medical challenges. In this next phase, Penumbra is set to broaden its reach on a global scale, and I am thrilled to join this excellent team and help accelerate the impact of its products.”

The company also revealed that their Indigo System Lightning 12 (Penumbra) is now commercially available in the USA. “Lightning 12 provides physicians with an integrated system that not only removes large amounts of thrombus but also detects and manages clot removal,” comments Jay Mathews (Manatee Memorial Hospital, Bradenton, USA).

Adam Elsesser, president and chief executive officer, Penumbra, remarks: “I am thrilled we are bringing Lightning 12, the most advanced technology for aspiration thrombectomy, to the peripheral interventional community. It is an ideal time for us to welcome Corey and Jim to Penumbra’s leadership team as we progress into our next phase of growth.”

Calendar of events Please be advised that the events listed opposite, because of COVID-19, are subject to change. Please check the relevant website for further details as the event may be cancelled, postponed, or become a virtual event.

8–11 September CX Aortic Vienna Online

6–8 November VIVA: Vascular Interventional Advances Online

23–27 February VEITHsymposium New York, USA

29 September–29 October ESVS Month Online

24–27 November Vascular Societies’ Annual Scientific Meeting Online

7–9 March 24th European Vascular Course (EVC) Maastricht, the Netherlands

www.cxsymposium.com/cxaortic

www.esvs.org

16–17 October Critical Issues in Aortic Endografting Paris, France www.critical-issues-congress.com

www.vivaphysicians.org

www.vascularsociety.org.uk

2021 26–29 January LINC – The Leipzig Interventional Course Leipzig, Germany

www.veithsymposium.org

www.vascular-course.com

2–5 June Society for Vascular Surgery (SVS) Vascular Annual Meeting San Diego, USA www.vascular.org

www.leipzig-interventional-course.com

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2019 | Issue

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nted” “Unprecede t developmen ic of NICE aort guideline aneurysm

Institute N of the National guideline VERSIO THE DRAFT Care Excellence (NICE) on in and for consultati for Health when released that patients with ndation created a furore, be offered its recomme should only 2018, with d aneurysm able to undergo an unrupture if they were fit and providers open surgery, . Many surgeons, service guideline draft the procedure ers have called the n has been and stakehold and its publicatio “unimplementable” since then.

Board,” deferred the NICE repeatedly of the now sits with UK), president “The guideline (London, and Ireland Loftus Ian Britain says for Great nted. “There Vascular Societycalls this step unprecede re-wording who sides and (VSGBI), ise on both ,” he tells Vascular the must be comprom workable guidance closely with to make this that NICE is working .

News, noting progress the guideline onal Interventi ers to Society of stakehold in discussion the British VSGBI and together been of (BSIR) have cated the concerns of Radiology and communi a letter to members with NICE g ty. In challengin communi has been set the vascular writes: “It is no date VSGBI, Loftus and at present there with NICE, for all concernedWe remain in touch help to find a n. to our for publicatio reiterated our desire Conte interests of Michael about the fact that [...] and have is in the best “to recognise solution that did raise our concerns and tening workable Conte said, limb-threa NICE The He adds: “We constitutes this problem,” s, with both scenarios. patients.” practice, what of the guideline in different it.” in current suggests that to change the wording may be different limb ischaemia were unable ischaemia below which of critical BSIR, but is okay. value of perfusion previous concept everyone threshold which there is some and above the expanding is critical, 4 diabetes and on page everyone is that with Continued What we realised

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