Feline Cardiology E-Book

Etienne Côté

• Herausgeber: John Wiley & Sons
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 1306

Veröffentlichungsjahr: 2011

Beschreibung

Feline Cardiology is the first book dedicated to thediagnosis and treatment of heart disease in cats. Designedfor use in clinical practice, this reference combines cutting-edgeinformation with practical applications, using a consistent formatfor ease of use. Feline Cardiology provides detailed,species-specific information that is absent from other texts, withan emphasis on the most commonly encountered feline cardiovasculardiseases. Drawing on the expertise of four internationally recognizedauthors, the book is packed with state-of-the-art informationwithin the framework of daily practice. Coverage ranges frombasic and advanced treatment approaches for cardiomyopathies,arrhythmias, and many other disorders to the newest information ongenetic testing, circulating markers of heart disease, andmore. Feline Cardiology provides a comprehensivesingle resource to managing cardiovascular disease in cats and is awelcome addition to any small animal practice library.

Leseprobe

Table of Contents

Cover

Title page

Copyright page

Dedications

Preface

Acknowledgments

Authors

SECTION A: Clinical Entities

1 Heart Murmurs and Gallop Heart Sounds

INTRODUCTION

HEART MURMURS

GALLOP HEART SOUNDS

2 Exercise Intolerance and Syncope

INTRODUCTION

ETIOLOGY AND PATHOPHYSIOLOGY

SIGNALMENT

HISTORY AND CHIEF COMPLAINT

PHYSICAL EXAMINATION

DIFFERENTIAL DIAGNOSIS

DIAGNOSTIC TESTING

TREATMENT

OUTCOME AND PROGNOSIS

EXERCISE INTOLERANCE

3 Pleural Effusion

4 Dyspnea and Cough

5 Cardiopulmonary Arrest and Cardiopulmonary Cerebral Resuscitation

CARDIOPULMONARY ARREST

DIAGNOSIS

DIFFERENTIAL DIAGNOSIS

TREATMENT

OUTCOME

SECTION B: Diagnostic Testing

6 Radiography

7 Echocardiography

INTRODUCTION

ECHOCARDIOGRAPHY BASICS

ECHOCARDIOGRAPHIC EQUIPMENT

PERFORMING THE ECHOCARDIOGRAM

ECHOCARDIOGRAPHIC ASSESSMENT OF DIASTOLIC FUNCTION

CONTRAST ECHOCARDIOGRAPHY

8 Cardiac Biomarkers

INTRODUCTION

HOMOCYST(E)INE AND B VITAMINS

ENDOTHELIN I

CARDIAC TROPONINS

NATRIURETIC PEPTIDES (ATRIAL AND B-TYPE NATRIURETIC PEPTIDE; ANP AND BNP)

9 Electrocardiography

INTRODUCTION

TECHNIQUE

NORMAL EVOLUTION OF THE ECG THROUGH LIFE

HOLTER AND EVENT MONITORING

SECTION C: Congenital Heart Disease

10 Congenital Heart Malformations

INTRODUCTION

HISTORY AND CHIEF COMPLAINT

PHYSICAL EXAMINATION

COMPLICATIONS AND MONITORING

ATRIOVENTRICULAR VALVE MALFORMATIONS: TRICUSPID VALVE MALFORMATION

MITRAL VALVE MALFORMATION/DYSPLASIA

MITRAL VALVE STENOSIS

VENTRICULAR SEPTAL DEFECT

AORTIC STENOSIS

ATRIAL SEPTAL DEFECT

COMMON AV CANAL (ENDOCARDIAL CUSHION DEFECT)

COR TRIATRIATUM SINISTER

DOUBLE CHAMBER RIGHT VENTRICLE

PATENT DUCTUS ARTERIOSUS

PULMONIC STENOSIS, PULMONARY ARTERY STENOSIS

TETRALOGY OF FALLOT

SECTION D: Cardiomyopathies

11 Hypertrophic Cardiomyopathy

INTRODUCTION

ETIOLOGY

GROSS PATHOLOGY

PATHOPHYSIOLOGY

SIGNALMENT

HISTORY AND CHIEF COMPLAINT

PHYSICAL EXAMINATION

DIFFERENTIAL DIAGNOSIS

DIAGNOSTIC TESTING

TREATMENT

COMPLICATIONS AND MONITORING

OUTCOME AND PROGNOSIS

12 Restrictive/Unclassified Cardiomyopathy

RESTRICTIVE CARDIOMYOPATHY

ETIOLOGY, PATHOPHYSIOLOGY, AND GROSS PATHOLOGY

SIGNALMENT

HISTORY AND CHIEF COMPLAINT

PHYSICAL EXAMINATION

DIFFERENTIAL DIAGNOSIS

DIAGNOSTIC TESTING

TREATMENT

COMPLICATIONS AND MONITORING

OUTCOME AND PROGNOSIS

13 Dilated Cardiomyopathy

INTRODUCTION

ETIOLOGY, PATHOPHYSIOLOGY, AND GROSS PATHOLOGY

SIGNALMENT

HISTORY AND CHIEF COMPLAINT

PHYSICAL EXAMINATION

DIFFERENTIAL DIAGNOSIS

DIAGNOSTIC TESTING

TREATMENT

COMPLICATIONS AND MONITORING

OUTCOME AND PROGNOSIS

14 Arrhythmogenic Right Ventricular Cardiomyopathy

INTRODUCTION

ETIOLOGY, PATHOPHYSIOLOGY, AND GROSS PATHOLOGY

SIGNALMENT

HISTORY AND CHIEF COMPLAINT

PHYSICAL EXAMINATION

DIFFERENTIAL DIAGNOSIS

DIAGNOSTIC TESTING

TREATMENT

COMPLICATIONS AND MONITORING

OUTCOME AND PROGNOSIS

SECTION E: Other Forms of Structural Heart Disease

15 Acquired Valvular Disease

DEGENERATIVE VALVE DISEASE

DIAGNOSIS

DIFFERENTIAL DIAGNOSIS

INFECTIVE ENDOCARDITIS

16 Cardiac Neoplasia

INTRODUCTION

PREVALENCE, ETIOLOGY, PATHOPHYSIOLOGY, AND GROSS PATHOLOGY

SIGNALMENT

HISTORY AND CHIEF COMPLAINT

PHYSICAL EXAMINATION

DIFFERENTIAL DIAGNOSIS

DIAGNOSTIC TESTING

TREATMENT

OUTCOME AND PROGNOSIS

17 Miscellaneous Myocardial Disease

MYOCARDITIS

ENDOCARDIAL FIBROELASTOSIS

EXCESSIVE LEFT VENTRICULAR MODERATOR BANDS

SECTION F: Arrhythmias and Other Electrocardiographic Abnormalities

18 Arrhythmias and Other Electrocardiographic Abnormalities

INTRODUCTION

ETIOLOGY, PATHOPHYSIOLOGY, AND GROSS PATHOLOGY

CLINICAL ELECTROCARDIOLOGY

SPECIFIC ARRHYTHMIAS

CARDIAC EFFECTS OF SYSTEMIC POTASSIUM AND CALCIUM ABNORMALITIES

MORPHOLOGIC ECG ABNORMALITIES

SECTION G: Congestive Heart Failure

19 Congestive Heart Failure

DEFINITIONS

INTRODUCTION

PATHOPHYSIOLOGY AND GROSS PATHOLOGY

SIGNALMENT

HISTORY AND CHIEF COMPLAINT

PRECIPITATING FACTORS THAT MAY CONTRIBUTE TO CONGESTIVE HEART FAILURE

PHYSICAL EXAMINATION

DIFFERENTIAL DIAGNOSIS

DIAGNOSTIC TESTING

TREATMENT

COMPLICATIONS AND MONITORING

OUTCOME AND PROGNOSIS

SECTION H: Arterial Thromboembolism

20 Arterial Thromboembolism

INTRODUCTION

PATHOPHYSIOLOGY AND GROSS PATHOLOGY

SIGNALMENT

HISTORY AND CHIEF COMPLAINT

DIFFERENTIAL DIAGNOSIS

DIAGNOSTIC TESTING

TREATMENT

COMPLICATIONS AND MONITORING

LONG-TERM OUTCOME AND PROGNOSIS

SECTION I: Systemic Hypertension

21 Systemic Hypertension

INTRODUCTION

ETIOLOGY, PATHOPHYSIOLOGY, AND GROSS PATHOLOGY

SIGNALMENT

HISTORY AND CHIEF COMPLAINT

PHYSICAL EXAMINATION

DIFFERENTIAL DIAGNOSIS

DIAGNOSTIC TESTING

TREATMENT

MONITORING

OUTCOME AND PROGNOSIS

SECTION J: Pericardial Diseases

22 Pericardial Effusion and Other Disorders of the Pericardium

INTRODUCTION

CONGENITAL PERICARDIAL DISEASES

ACQUIRED PERICARDIAL DISEASES

CONSTRICTIVE PERICARDITIS

SECTION K: Heartworm Disease

23 Heartworm Disease

INTRODUCTION

ETIOLOGY AND LIFE CYCLE

HISTORY, CHIEF COMPLAINT, PHYSICAL EXAMINATION

DIAGNOSIS

TREATMENT

MONITORING

OUTCOME AND PROGNOSIS

SECTION L: Comorbidities

24 Comorbidities: Managing Cats That Have Coexistent Cardiac Disease and Extracardiac Disorders

INTRODUCTION

CONCURRENT HEART DISEASE AND KIDNEY DISEASE

CARDIAC DISEASE AND IDIOPATHIC CYSTITIS/FELINE LOWER URINARY TRACT SIGNS

CARDIAC DISEASE AND FELINE ASTHMA

CONCURRENT CARDIAC DISEASE AND OTHER DISORDERS TREATED WITH GLUCOCORTICOIDS

CARDIAC DISEASE AND UNRELATED PLEURAL EFFUSION

CRITICAL CARE REQUIRING FLUID THERAPY IN THE CAT WITH HEART DISEASE

SECTION M: Pulmonary Arterial Disorders

25 Pulmonary Thromboembolism and Pulmonary Hypertension

PULMONARY THROMBOEMBOLISM

PULMONARY ARTERIAL HYPERTENSION

SECTION N: Endocrine Diseases Affecting the Heart

26 Endocrine Diseases Affecting the Heart

HYPERTHYROIDISM

OTHER ENDOCRINOPATHIES

SECTION O: Anesthesia in the Patient with Cardiac Disease

27 Anesthesia in the Patient with Cardiac Disease

INTRODUCTION

PREANESTHETIC PREPARATION

ANESTHESIA

ANESTHETIZING THE FRACTIOUS CAT

SUPPORT AND MONITORING

TREATMENT

POSTOPERATIVE MONITORING AND RECOVERY

PLANNING ANESTHESIA IN THE CARDIAC PATIENT WITHOUT AN ECHOCARDIOGRAM

SECTION P: Cardiac Screening Programs

28 Cardiac Screening Programs

INTRODUCTION

CONGENITAL DEFECTS

HYPERTROPHIC CARDIOMYOPATHY

GENETIC SCREENING

OTHER FORMS OF CARDIOMYOPATHY

SECTION Q: Which Drug for Which Disease?

29 Which Drug for Which Disease?

INTRODUCTION

HYPERTROPHIC CARDIOMYOPATHY—COMPENSATED (“ASYMPTOMATIC”)

DILATED CARDIOMYOPATHY (DCM)

RESTRICTIVE/UNCLASSIFIED CARDIOMYOPATHY

CONGESTIVE HEART FAILURE

AORTIC THROMBOEMBOLISM

SYSTEMIC HYPERTENSION

CONGENITAL HEART DISEASE

ARRHYTHMIAS

SECTION R: Drug Formulary

30 Drug Formulary

Index

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Library of Congress Cataloging-in-Publication Data

Feline cardiology / Etienne Côté ... [et al.].

p. ; cm.

 Includes bibliographical references and index.

 ISBN 978-0-8138-1242-7 (hardcover : alk. paper)

 1. Cats–Diseases. 2. Veterinary cardiology. I. Côté, Etienne.

 [DNLM: 1. Cat Diseases. 2. Cardiovascular Diseases–veterinary. SF 985]

 SF985.F414 2011

 636.8'089–dc22

2011007198

A catalogue record for this book is available from the British Library.

This book is published in the following electronic formats: ePDF 9780470960165; ePub 9780470960172; Mobi 9780470960189

Disclaimer

The publisher and the authors make no representations or warranties with respect to the accuracy or completeness of the contents of this work and specifically disclaim all warranties, including without limitation warranties of fitness for a particular purpose. No warranty may be created or extended by sales or promotional materials. The advice and strategies contained herein may not be suitable for every situation. This work is sold with the understanding that the publisher is not engaged in rendering legal, accounting, or other professional services. If professional assistance is required, the services of a competent professional person should be sought. Neither the publisher nor the authors shall be liable for damages arising herefrom. The fact that an organization or website is referred to in this work as a citation and/or a potential source of further information does not mean that the authors or the publisher endorses the information the organization or Website may provide or recommendations it may make. Further, readers should be aware that Internet websites listed in this work may have changed or disappeared between when this work was written and when it is read.

Cover Image Credits—Top left image: Radiograph of a cat with a permanent epicardial pacemaker. Second left image: Echocardiogram of a cat with hypertrophic obstructive cardiomyopathy, showing systolic anterior motion of the mitral valve and associated mitral regurgitation and turbulence in the left ventricular outflow tract. Third left image: Electrocardiogram of a cat showing normal sinus rhythm and superimposed motion artifact caused by purring. Fourth left image: Spectral Doppler tracing obtained in the left ventricular outflow of a cat with dynamic left ventricular outflow tract obstruction. Bottom left image: Cardiac magnetic resonance image of a cat with hypertrophic cardiomyopathy. Right image: “Cat Eyes” by Barbara Hartsook, http://WithBrushandPen.com

For my father, François Côté, and in memory of my mother, Louise Martin, who have been my nature and nurture.

Etienne Côté

For my husband Jim, my mother Nancy, and my daughter Lexi: thank you for bringing so much happiness and support to my life and for encouraging my endeavors. Thank you to my mentor, Dr. Mark Kittleson, for giving me the opportunity and guidance in my research of feline hypertrophic cardiomyopathy.

Kristin A. MacDonald

For the many, many, many mentors (both human and feline) I have had along the way, thank you.

Kathryn M. Meurs

For Drs. David H. Knight and Jim W. Buchanan—I was privileged to be one of your students.

For Mary Jane, who always believed in me. Thank you, Granny.

For Dave, who loves me anyway.

Meg M. Sleeper

Preface

Cats are the most popular house pet in the United States, numbering some 88.3 million (contrasting with 74.8 million dogs) (HSUS 2010). Surveys suggest proportionally similar domestic feline populations in many other countries (Murray et al. 2010; Chambre Syndicale 2006; EPFIF 2010). Even so, a textbook dedicated to heart diseases of the cat has not existed until now. By contrast, the first textbook on cardiology of the dog was published over 40 years ago (Ettinger and Suter 1970). Therefore, much of the information on heart diseases of cats in current reference texts is presented in combination with information on heart diseases of dogs. Such an approach provides a framework but is insufficient, especially in practices where cats make up a substantial proportion of the caseload. Cats develop and manifest cardiac disease uniquely, in ways that often do not lend themselves to comparisons or extrapolations from other species.

Our ability to recognize feline heart disease continues to increase, and as a result, some studies suggest that the prevalence of heart disease in cats rivals or surpasses the prevalence of heart disease in humans (Paige et al. 2009). This awareness presents both opportunity and dilemma. What are the appropriate tests to diagnose heart disease in cats, and how can private practitioners best use them in daily practice? “Does every cat with a murmur need an echocardiogram?” Can some confounding factors influence the diagnosis of heart disease (Campbell and Kittleson 2007)? Should a cat be treated if structural changes of the heart are only discovered as an incidental finding? Is the prognosis guarded even if his/her cardiac disorder is stable for years? How should comorbidities be addressed in cats with underlying cardiac disease? Answers exist for some of these questions but not others; what is undeniable is the emergence of these questions in daily feline practice. Despite insufficient published information, dedicated cat owners expect veterinarians to diagnose and treat cats that have heart disease with a high level of proficiency and care.

As veterinarians, we are faced daily with the spectrum of feline heart disease. The severity of our feline patients’ problems ranges from the very mild to life-threatening and devastating situations. A multiauthor consensus for providing optimal diagnosis and treatment in an attempt to attain the best overall outcome seemed useful but was lacking in existing texts.

All of these observations pointed to a need for more information, which we chose to address by creating this book. Our primary goal has been to collect and present clinically relevant and applicable approaches to the evaluation and treatment of feline heart disease. Above all, the book is meant to be useful in clinical practice. Within this approach, we have also included advanced or state-of-the-art material as appropriate.

We have aimed to describe and explain the intricacies and nuances of feline heart disease, and the uniqueness of feline heart disease, as we see them. Like so many branches of veterinary medicine, feline cardiology suffers from having few formally accepted guidelines to direct the practice and application of the discipline. This book represents our collective effort at identifying and providing the published information that does exist, interwoven with our own experience, opinions, and practice approaches when peer-reviewed data were lacking.

Several features of this book demonstrate the way in which we have sought to reach these goals, including

Emphasis on clinically relevant aspects of naturally occurring heart disease in the cat. The cardiomyopathies, aortic thromboembolism, heart murmurs, congestive heart failure, and other cornerstones of feline cardiovascular disease are explored in detail. The largest part of the book describes individual cardiovascular diseases as they occur in the veterinary setting. The length of chapters deliberately reflects the importance of individual diseases, so that reader-practitioners may find the most information on the diseases they encounter most often.Organization in a predictable and user-friendly format. Chapters begin with key points to summarize the most important elements of each chapter and then proceed through the natural sequence of information, typically: introduction, pathophysiology, signalment, history, physical exam, and so on.Anticipation and recognition of the realities of veterinary practice. For example, Chapter 27 on general anesthesia contains sections on “Anesthetizing the Fractious Cat” and “Planning Anesthesia in the Cardiac Patient without an Echocardiogram”; Chapter 29 summarizes treatment recommendations for the most common feline heart diseases in a streamlined way and is titled simply “Which Drug for Which Disease?”; Chapter 24 describes managing heart disease in cats that have concurrent kidney disease, allergic airway disease, and other comorbidities; and Chapter 30 is a drug index that serves as a quick reference to the commonly—and less commonly—used cardiovascular medications for cats.Presentation of new and innovative information, ranging from cardiac biomarkers and cardiac magnetic resonance imaging to current approaches for genetic screening programs and prebreeding evaluation of cats for heart disease.Full-color illustrations. Photographs present physical abnormalities, diagnostic images, and other visually engaging material as clearly as possible.Inclusion of reference citations in print at the end of each chapter to allow for quick referencing without needing to consult a CD or website.Comprehensive normal feline reference values for cardiovascular parameters and diagnostic tests including electrocardiography, echocardiography, and thoracic radiography are available on the inside covers for immediate access.

We were fortunate to benefit from the advantages of communications technology throughout the creation of this book. We wished to have the best of both worlds: taking advantage of our individual strengths and regional exposure, while creating a textbook that is seamless and uniform in style. This was made possible by numerous conference calls and a 6-month comprehensive review period that involved all four of us in a series of 15 desktop-synchronized teleconferences. As a result, each one of us has reviewed and discussed every chapter. We hope readers find that the result is a textbook that is both insightful and cohesive.

This book is resolutely and unapologetically devoted to the cat. Nevertheless, we strived to present cardiology concepts and medical reasoning with the greatest possible clarity, and our hope is that readers not primarily interested in learning about cats will still find that our explanations help them understand cardiology in general.

REFERENCES

Campbell F, Kittleson MD. The effect of hydration status on the echocardiographic measurements of normal cats. J Vet Intern Med 2007;21:1008–1015.

Chambre Syndicale des Fabricants d’Aliments Préparés pour Chiens, Chats, Oiseaux, et Autres Animaux Familiers (FACCO). Survey of pet ownership in France, 2006. http://www.facco.fr/Resultats-de-l-enquete-2006. Accessed July 14, 2010.

Ettinger SJ, Suter PF. Canine Cardiology. Philadelphia, Saunders, 1970.

European Pet Food Industry Federation (EPFIF). Survey of Pet Ownership in Europe. http://www.fediaf.org/gentree.htm. Accessed July 14, 2010.

Humane Society of the United States (HSUS). http://www.hsus.org/pets/issues_affecting_our_pets/pet_overpopulation_and_ownership_statistics/us_pet_ownership_statistics.html. Accessed 7/14/10.

Murray JK, Browne WJ, Roberts MA, Whitmarsh A, Gruffydd-Jones TJ. Number and ownership profiles of cats and dogs in the UK. Vet Rec 2010;166:163–168.

Paige CF, Abbott JA, Elvinger F, Pyle RL. Prevalence of cardiomyopathy in apparently healthy cats. J Am Vet Med Assoc 2009;234: 1398–1403.

Acknowledgments

We thank the group at Wiley-Blackwell, notably Antonia Seymour, Erica Judisch, Erin Magnani, Nancy Turner, Nancy Albright, Justin Jeffryes, and Ray Kersey, for the spark that started this project and their unfailing support throughout its preparation and completion. Their efforts successfully transformed a series of Word documents and digital images into this attractive book.

We owe a great deal of gratitude to many people who helped us make this book possible. Several colleagues, notably Drs. John Bonagura, Phil Fox, Steve Ettinger, Fiona Campbell, and others provided their feedback, their own materials, or both, for us to include in this book. We are truly thankful for their incredible generosity.

Dr. Bruno Pypendop, DrMedVet, DrVetSci, Dipl. ACVA, Associate Professor, Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, lent his expertise to our group to create an outstanding chapter on general anesthesia in cats with cardiovascular disease (Chapter 27). We thank him sincerely for his dedication of time and his generous contribution of a truly clinically relevant, insightful chapter.

The American Association of Feline Practitioners and the International Association of Cat Doctors kindly responded to our requests by offering dozens of ideas and suggestions for what a good feline cardiology book should contain. We are truly grateful to them for this contribution. This feedback “from the trenches” was extremely valuable, both for confirming the importance of what we planned to include and for proposing new ideas.

Many thanks are due to graphic illustrators John Doval and Maggie Lillo, who transformed our rudimentary ideas and basic sketches into several beautiful, clear, engaging illustrations.

Finally, and above all, we thank our coworkers, friends, and family. Their understanding and support allowed us to make this book a reality.

Authors

Etienne Côté DVM, Diplomate ACVIM (Cardiology, Small Animal Internal Medicine)

Kristin A. MacDonald, DVM, PhD, Diplomate ACVIM (Cardiology)

Kathryn M. Meurs, DVM, PhD, Diplomate ACVIM (Cardiology)

Meg M. Sleeper VMD, Diplomate ACVIM (Cardiology)

2

Exercise Intolerance and Syncope

Key Points

Syncope is an uncommon occurrence in cats.When it occurs, it most commonly is the result of an arrhythmia—typically a pathologic bradycardia—in a cat with underlying structural heart disease, but systemic illness and tachycardias can cause syncope in cats.Detailed diagnostic evaluation is essential in order to confirm syncope and rule out neurologic or other phenomena.