Presentation brochure
Pet owner educational atlas
Cardiorespiratory system Review and texts: Germรกn Santamarina
Pet owner educational atlas
Pet owner educational atlas
Cardiorespiratory system
Cardiorespiratory system
Review and texts: Germán Santamarina
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review and texts: Germán Santamarina. Format: 22 x 28 cm. Number of pages: 76. Number of SHEETS: 70. binding: hardcover, wire-o.
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75 €
This new volume of the Pet owner educational atlas collection on
eBook included
the cardiorespiratory system of dogs and cats pursues the same objective as the previous books: helping veterinary surgeons to communicate with pet owners. In addition, as its contents are focused on one single system, the specificity of the topics addressed will also help veterinary practitioners to consolidate and broaden their knowledge.
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Pet owner EDUCATIONAL atlas l Cardiorespiratory system
Presentation of the book It is essential that owners understand what is happening to their pet and how their veterinary surgeon may address the problem to ensure they accept and get involved in the treatment. Veterinary surgeons will be able to rely on this book to give clear and accessible explanations and make the time spent on this task more profitable. The topics addressed include the physiology of the cardiorespiratory system, the main diagnostic tests that may be used and the pathological processes and diseases that affect the heart and lungs and may have a negative impact on other systems. The clarity and accuracy of the illustrations in each chart, accompanied by the texts of Germán Santamarina, a specialist in the field, turn this atlas into a useful tool for daily practice.
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Pet owner EDUCATIONAL atlas l Cardiorespiratory system
Review and texts Germán Santamarina Pernas Degree and PhD in Veterinary Medicine from the University of Santiago de Compostela (USC) and Professor of Medical Pathology at the Department of Veterinary Clinical Sciences of the Faculty of Veterinary Medicine of Lugo, USC. AVEPA (Spanish association of small animal veterinary practitioners) certified in Internal Medicine and Cardiology. He has been a visiting scholar in Cardiology and Internal Medicine at the schools of veterinary medicine of the universities of Davis (USA), Bologne (Italy), Alfort (France) and Lyon (France).
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He works as a veterinary clinician at the Internal Medicine Service of the Rof Codina Veterinary Teaching Hospital, where he is the head of the Cardiology Unit.
Communication services Web site Online visualisation of the sample chapter. Presentation brochure in PDF format. Author´s CV. Sample chapter compatible with iPad.
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Pet owner educational atlas
Cardiorespiratory system Review and texts: Germรกn Santamarina
Table of contents 1. Anatomy and physiology of the cardiovascular system ■■
Heart anatomy
■■
Conduction system
■■
Circulatory system
2. Congenital cardiovascular diseases ■■
Subaortic stenosis
■■
Pulmonary stenosis
■■
Patent ductus arteriosus
■■
Ventricular septal defect (VSD)
■■
Atrial septal defect (ASD)
■■
Reverse shunts
■■
Mitral and tricuspid valve dysplasia
■■
Tetralogy of Fallot
■■
Persistent right aortic arch
■■
Cor triatriatum sinister and dexter
3. Acquired heart diseases Acquired valvular diseases ■■
Chronic valvular degeneration
■■
Infectious endocarditis
Myocardial diseases of the dog ■■
Canine dilated cardiomyopathy
■■
Boxer arrhythmogenic right ventricular cardiomyopathy
■■
Myocarditis
Myocardial diseases of the cat ■■
Feline hypertrophic cardiomyopathy
■■
Feline restrictive cardiomyopathy
■■
Feline dilated cardiomyopathy
■■
Feline arrhythmogenic cardiomyopathy
Pericardial diseases and heart tumours ■■
Pericardial effusion
■■
Peritoneopericardial diaphragmatic hernia
■■
Heart tumours
Heartworms ■■
Heartworm disease
■■
Angiostrongylosis caused by Angiostrongylus vasorum
Miscellaneous cardiovascular diseases ■■
Pulmonary hypertension
■■
Systemic hypertension
Main cardiac arrhythmias ■■
Respiratory sinus arrhythmia
■■
Atrial fibrillation
■■
Premature ventricular contractions
■■
Atrioventricular blocks
■■
Wolff-Parkinson-White syndrome
4. Anatomy and physiology of the respiratory system ■■
Physiological anatomy of the respiratory system
5. Diseases of the respiratory system Nasal diseases ■■
Acute feline upper respiratory tract disease
■■
Fungal rhinitis: feline nasal cryptococcosis
■■
Fungal rhinitis: nasal aspergillosis in dogs
■■
Feline chronic rhinosinusitis
■■
Canine lymphoplasmacytic rhinitis
■■
Feline nasopharyngeal polyps
■■
Tumours of the nasal cavity
■■
Nasal foreign body
■■
Brachycephalic syndrome
Diseases of the airways ■■
Laryngeal paralysis
■■
Laryngitis
■■
Tumours of the larynx and trachea
■■
Tracheal collapse
■■
Infectious tracheobronchitis
■■
Primary ciliary dyskinesia
■■
Canine chronic bronchitis
■■
Feline asthma/bronchitis
Diseases of the lung parenchyma ■■
Bacterial pneumonia
■■
Aspiration pneumonia
■■
Viral pneumonia
■■
Fungal pneumonia
■■
Eosinophilic bronchopneumonia
■■
Pulmonary fibrosis
■■
Pulmonary oedema
■■
Bronchial and pulmonary tumours
■■
Lung lobe torsion
■■
Pulmonary thromboembolism
■■
Pulmonary parasites
Diseases of the pleura and mediastinum ■■
Pneumothorax and neumomediastinum
■■
Diaphragmatic hernia
■■
Transudative pleural effusion
■■
Pyothorax
■■
Chylothorax
■■
Haemothorax
■■
Pleural and mediastinal neoplasms
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PET OWNER EDUCATIONAL ATLAS. CARDIORESPIRATORY SYSTEM
Conduction system
2
The cardiac conduction system is a group of specialised cells responsible for generating and conducting the electrical impulse that enables the heart to beat in a rhythmic and coordinated manner. Components and function of the conduction system 1. Sinus node: located in the upper part of the right atrium, it is the heart’s natural pacemaker, responsible for generating the electrical impulse that initially travels through the atria, thus causing their contraction. 2. Atrioventricular node: it is located in the lower part of the interatrial septum. The electrical signal that has spread through the atria can only continue through the atrioventricular node, where it is delayed for a very short period of time before travelling through the ventricles.
1 2
3
3. Bundle of His: it is a bridge between the atrioventricular node and the left and right branches, which are fast electrical conduction pathways to the two ventricles. These branches terminate in a network of fibres named Purkinje fibres, which end within the myocardium.
Movement of the electrical impulse
R
R
P
P
T
T Q
The electrocardiogram (ECG) is one of the main tools to assess the electrical activity of the heart and diagnose abnormalities of the cardiac conduction system.
S
Q
S
This sequence allows the atria to contract first and then the ventricles.
R R
P T Q
P T
S Q
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9 ANATOMY AND PHYSIOLOGY OF THE CARDIOVASCULAR SYSTEM
3 Circulatory system The cardiovascular system is formed by the heart, which acts as a blood pump, and the blood vessels, which are responsible for transporting blood and distributing it throughout all the tissues in the organism.
Systemic circulation
■■ The
oxygen-rich blood coming from the pulmonary veins enters the left heart. ■■ The contraction of the left ventricle pumps the blood through the aortic valve into the aorta, which branches into arteries arteries, which in turn branch repeatedly into smaller vessels and finally into capillaries. Capillaries are the small vessels where the oxygen and nutrients are exchanged in all the tissues. ■■ Once the oxygen has been used, the deoxygenated blood returns to the right side of the heart to initiate a new cycle of pulmonary and systemic circulation.
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Pulmonary circulation
■■ The
deoxygenated blood from the whole body enters the right side of the heart through two large vessels named cranial and caudal venae cavae. ■■ The right ventricle pumps the blood through the pulmonary valve into the pulmonary artery to distribute it throughout the lungs in the pulmonary capillary vessels. ■■ The red blood cells pick up oxygen once again before leaving the lungs through the pulmonary veins.
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PET OWNER EDUCATIONAL ATLAS. CARDIORESPIRATORY SYSTEM
4
Subaortic stenosis Congenital narrowing of the outflow tract of the left ventricle, generally caused by a subvalvular fibrous ring. The obstruction causes an accelerated and turbulent blood flow into the aorta, which produces an audible heart murmur on auscultation. The heart responds to the resistance with hypertrophy of the left ventricle, which is proportional to the degree of stenosis. The appearance of ventricular arrhythmias often complicates this condition.
Clinical signs It is more common in large-breed dogs: the Terranova, Golden Retriever, Rottweiler and Boxer are among the most represented breeds. It is very rare in cats.
Normal aortic valve
■■ Mild
or moderate cases may be asymptomatic. ■■ Severely affected animals may show fatigue or intolerance to exercise and syncope. ■■ Cases of sudden death with no previous signs are common.
Diagnosis ■■ Echocardiography
shows left ventricular hypertrophy and a turbulent outflow. ■■ The severity of the stenosis is estimated with spectral Doppler to calculate the increase in the blood flow velocity through the obstruction.
Subvalvular fibrous ring
Hypertrophy of the right ventricle
In the most affected breeds, an early detection programme (auscultation, echocardiography) should be established and breeding of affected animals should be prevented.
Treatment ■■ Valvuloplasty ■■ In
(dilatation) of the stenosis using a balloon has not resulted in improvements in the survival rates. severe cases, the use of beta blockers is recommended to try to prevent sudden death.
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11 CONGENITAL CARDIOVASCULAR DISEASES
5 Pulmonary stenosis Congenital malformation of the pulmonary valve causing the obstruction of the outflow tract of the right heart, which produces a clearly audible murmur on auscultation. It is caused by: ■■ Fusion and thickening of the valve leaflets. ■■ Hypoplasia of the vascular ring.
It usually affects smallbreed dogs such as the English Bulldog, Beagle, miniature Schnauzer, West Highland White Terrier, Cocker Spaniel and others. It is very rare in cats.
Clinical signs
Normal pulmonary valve
■■ Severely
affected animals may show intolerance to exercise and syncope or sudden death. ■■ Some develop heart failure with ascites.
Diagnosis ■■ Ultrasonography
Poststenotic dilatation
Pulmonary stenosis (valvular fusion)
The right ventricle becomes hypertrophied to overcome the resistance
is the most accurate method to detect a pulmonary valve abnormality and right ventricular hypertrophy. ■■ The severity of the obstruction can be estimated by measuring the blood flow velocity using Doppler ultrasonography.
Affected animals should not be used for reproduction.
Treatment ■■ Mild
cases do not require any treatment. (dilatation) using a balloon is recommended in severe cases. ■■ The use of beta blockers is also indicated. ■■ Valvuloplasty
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PET OWNER EDUCATIONAL ATLAS. CARDIORESPIRATORY SYSTEM
6
Patent ductus arteriosus During the foetal stage, the ductus arteriosus connects the pulmonary artery with the aorta to derive the oxygen and nutrient-rich blood from the placenta towards the whole body. It should close a few hours after birth. Failure of this connection to close is named patent ductus arteriosus. It allows the abnormal passage of blood from the aorta towards the lungs, leading to pulmonary circulatory overload.
It may affect dogs of any breeds, although Maltese, Poodle and German Shepherd dogs are among the most affected dogs. The incidence in females is approximately 3 times as high as in males. It is less common in cats.
Clinical signs ■■ The
clinical picture varies from no signs to severe difficulty breathing. ■■ All affected animals have a very characteristic continuous heart murmur.
Diagnosis Auscultation of the murmur should be completed with thoracic X-rays and ultrasonography to confirm the disease and identify the patent ductus arteriosus.
This is a highly transmissible hereditary condition.
Ligatures
Coil device
Volume overload in the lungs
Amplatzer device
Treatment ■■ Treatment
involves closing the duct with a surgical ligature or by placing an occluding device via a transcatheter approach. ■■ The duct should be closed as early as possible to avoid any irreversible complications.
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41 ANATOMY AND PHYSIOLOGY OF THE RESPIRATORY SYSTEM
35 Physiological anatomy
of the respiratory system The respiratory system is responsible for taking up oxygen (O2) from the air and transferring it to the blood so it can be distributed throughout the tissues, and for expelling the carbon dioxide (CO2) produced by cellular metabolism to the exterior. The respiratory system is formed by the upper airways, lower airways, lungs and pleura. The lungs are protected by the thoracic cavity, which is made up of the sternum, ribs and spine. Nasal cavity Nasal sinuses Pharynx Larynx
Upper airways
Nose
Right lung
Left lung
Ribs
Bronchi
Intercostal muscles Visceral pleura Parietal pleura
Bronchioles Alveoli
Lower airways
Trachea
Diaphragm
Blood capillaries
O2 and CO2 exchange Gas exchange occurs in the alveoli, which are surrounded by blood capillaries to which the O2 from the air is transferred and from which CO2 is picked up. Thus, poorly oxygenated and CO2-rich blood is taken from the right side of the heart to the lungs, while oxygenated and CO2-poor blood leaves the lungs to the left side of the heart to be distributed to the whole organism.
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Alveoli
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PET OWNER EDUCATIONAL ATLAS. CARDIORESPIRATORY SYSTEM
Nasal conditions
38 Fungal rhinitis:
nasal aspergillosis in dogs The most frequent cause of fungal rhinitis in dogs is an infection by the fungus Aspergillus fumigatus, which is ubiquitous in the environment. It is acquired by inhalation or associated with the penetration of a foreign body into the nose, and causes inflammation of the nasal cavity and sinuses with formation of granulomas or fungal plaques. The fungal toxins and the inflammatory response cause the destruction of the turbinates and nasal septum.
Dogs with a long muzzle (dolicephalic) are more commonly affected.
Clinical signs ■■ Long
clinical history (4–6 months) of purulent or haemorrhagic nasal discharge, usually unilateral, and sneezing. The discharge often causes the loss of pigmentation of the nostrils. ■■ Pain: the dog walks with the head down and shows signs of pain upon palpation of the head.
Aspergillus fumigatus
Diagnosis ■■ It
is confirmed by diagnostic imaging studies, such as a CT scan or rhinoscopy, which reveal destruction of the turbinates and fungal plaques and allow the collection of samples for culture. ■■ Serological detection of antibodies against the fungus can back up the diagnosis.
Treatment Nasal aspergillosis in dogs is best treated with local application of clotrimazole or enilconazole after placing catheters in the animal’s nostrils or sinuses under anaesthesia so the drugs can be topically instilled for an hour.
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47 DISEASES OF THE RESPIRATORY SYSTEM
Nasal conditions
41 Feline nasopharyngeal polyps They are non-neoplastic masses composed of fibrous inflammatory tissue, which originate in the auditory tube and may extend to the ear canal or to the nasopharynx. The polyps that grow towards the ear canal occupy the middle ear, causing inflammation and accumulation of secretions, and may even protrude into the ear canal. Those that grow towards the nasopharynx obstruct the airflow when breathing and prevent the drainage of nasal secretions.
Clinical signs ■■ Nasopharyngeal
polyps cause noisy breathing, nasal discharge and difficulty to swallow. ■■ When they affect the middle ear, cats shake their heads and ear discharge may be observed.
It essentially affects young kittens and a congenital or viral origin is suspected.
Auditory tube Tympanic membrane Polyp in the ear canal Tympanic cavity Polyp in the nasopharynx
Diagnosis ■■ Visual
examination of the ear canal, pharynx or nasopharynx under anaesthesia. ■■ A CT scan provides more precise information about the extension of the polyp.
Treatment ■■ The
polyp is usually removed by traction. there is residual tissue that grows back, which requires tympanic bulla osteotomy to remove the remaining tissue.
■■ Sometimes
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PET OWNER EDUCATIONAL ATLAS. CARDIORESPIRATORY SYSTEM
Nasal diseases
44 Brachycephalic syndrome Congenital condition caused by several alterations that obstruct the flow of air through the upper airways. ■■ Stenotic nares. ■■ Aberrant nasal turbinates. ■■ Elongated and thickened soft palate. ■■ Enlarged tonsils. ■■ Collapsed laryngeal cartilage. ■■ Everted laryngeal saccules. ■■ Hypoplastic trachea in some breeds.
Clinical signs ■■ Nasal
sounds when breathing, such as rales and rhonchi. to exercise and difficulty breathing. ■■ Affected animals have great trouble coping with heat and may faint. ■■ Intolerance
Surgical correction
This syndrome is common in short-nosed breeds: Bulldog (English and French), Pug, Boston Terrier. ■■ Cats: Himalayan and Persian. ■■ Dogs:
The excessive length of the soft palate makes the flow of air more difficult
Diagnosis Feline brachycephaly causes obstruction of the upper airways
■■ Direct
examination to assess the narrowing of the nares and the length of the soft palate. ■■ Radiography or endoscopy to observe the degree of involvement of all the structures involved.
Treatment ■■ Weight
loss is essential to reduce the effort to breathe. ■■ They key is surgical correction of the abnormalities, mainly widening of the stenotic nares and resection of the soft palate. ■■ Surgery should be performed as soon as the clinical signs are observed to avoid secondary complications.
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The publishing strength of Grupo AsĂs Editorial Servet, a division of Grupo AsĂs, has become one of the reference publishing companies in the veterinary sector worldwide. More than 15 years of experience in the publishing of contents about veterinary medicine guarantees the quality of its work. With a wide national and international distribution, the books in its catalogue are present in many different countries and have been translated into nine languages to date: English, French, Portuguese, German, Italian, Turkish, Japanese, Russian and Chinese. Its identifying characteristic is a large multidisciplinary team formed by doctors and graduates in Veterinary Medicine and Fine Arts, and specialised designers with a great knowledge of the sector in which they work. Every book is subject to thorough technical and linguistic reviews and analyses, which allow the creation of works with a unique design and excellent contents. Servet works with the most renowned national and international authors to include the topics most demanded by veterinary surgeons in its catalogue. In addition to its own works, Servet also prepares books for companies and the main multinational companies in the sector are among its clients.
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