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(BQ) Part 1 book Textbook of clinical echocardiography presents the following contents: Principles of echocardiographic image acquisition and doppler analysis, normal anatomy and flow patterns on transthoracic echocardiography, transesophageal echocardiography, advanced echocardiographic modalities,...

Look for These Other Titles in the Otto Echocardiography Family / 9 Echocardiography Review Guide: Companion to the Textbook of Clinical Echocardiography, Second Edition Catherine Otto, Rebecca Schwaegler, and Rosario Freeman r i h The Practice of Clinical Echocardiography, Fourth Edition Catherine Otto a t r/ Practical Echocardiography Series Series Editor: Catherine Otto e s Volumes Included in This Series: Advanced Approaches in Echocardiography Linda Gillam and Catherine Otto /r u Intraoperative Echocardiography Donald Oxorn t c a k Echocardiography in Heart Failure Martin St John Sutton and Susan Wiegers /: / Echocardiography in Congenital Heart Disease Mark Lewin and Karen Stout h s tt p f Fi th Edition o C a t h e r i n e M O t t , m TEXTBOOK of CLINICAL / ECHOCARDIOGRAPHY d h a t r/ J Ward Kennedy-Hamilton Endowed Chair in Cardiology e s Professor of Medicine University of Washington School of Medicine; /r u Director, Heart Valve Disease Clinic Associate Director, Echocardiography Laboratory t c a k University of Washington Medical Center Seattle, Washington h s tt p /: / ri 1600 John F Kennedy Blvd Ste 1800 Philadelphia, PA 19103-2899  TEXTBOOK OF CLINICAL ECHOCARDIOGRAPHY ISBN: 978-1-4557-2857-2 Copyright © 2013, 2009, 2004, 2000, 1995 by Saunders, an imprint of Elsevier Inc ­ No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher Details on how to seek permission, further information about the Publisher’s permissions policies and our arrangements with organizations such as the Copyright Clearance Center and the Copyright Licensing Agency, can be found at our website: www.elsevier.com/permissions r i h This book and the individual contributions contained in it are protected under copyright by the Publisher (other than as may be noted herein) a t r/ Notices Knowledge and best practice in this field are constantly changing As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein In using such information or methods they should be mindful of their own safety and the safety of others, including parties for whom they have a professional responsibility With respect to any drug or pharmaceutical products identified, readers are advised to check the most current information provided (i) on procedures featured or (ii) by the manufacturer of each product to be administered, to verify the recommended dose or formula, the method and duration of administration, and contraindications It is the responsibility of practitioners, relying on their own experience and knowledge of their patients, to make diagnoses, to determine dosages and the best treatment for each individual patient, and to take all appropriate safety precautions To the fullest extent of the law, neither the Publisher nor the authors, contributors, or editors, assume any liability for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions, or ideas contained in the material herein .t c a k e s /r u Library of Congress Cataloging-in-Publication Data Otto, Catherine M Textbook of clinical echocardiography / Catherine M Otto.—5th ed p ; cm.—(Endocardiography) Includes bibliographical references and index ISBN 978-1-4557-2857-2 (alk paper) I Title II Series: Endocardiography [DNLM: Echocardiography Heart Diseases—ultrasonography WG 141.5.E2] 616.1′207543—dc23  s tt p /: / h Executive Content Strategist: Dolores Meloni Senior Content Development Specialist: Joan Ryan Publishing Services Manager: Deborah Vogel Project Manager: Brandilyn Flagg Designer: Lou Forgione Printed in Canada Last digit is the print number: / 9 2012044607 PREFACE Echocardiography is an integral part of clinical cardiology with important applications in diagnosis, clinical management, and decision making for patients with a wide range of cardiovascular diseases In addition to examinations performed in the echocardiography laboratory, ultrasound imaging is now used in a variety of other clinical settings, including the coronary care unit, intensive care unit, operating room, emergency department, catheterization laboratory, and electrophysiology laboratory, both for diagnosis and for monitoring the effects of therapeutic interventions There continues to be expansion of echocardiographic applications, given the detailed and precise anatomic and physiologic information that can be obtained with this technique at a relatively low cost and with minimal risk to the patient This textbook on general clinical echocardiography is intended to be read by individuals new to echocardiography and by those interested in updating their knowledge in this area The text is aimed primarily at cardiology fellows on their basic echocardiography rotation but also will be of value to residents and fellows in general internal medicine, radiology, anesthesiology, and emergency medicine, and to cardiac sonography students For physicians in practice, this textbook provides a concise and practical update The Textbook of Clinical Echocardiography is structured around a clinical approach to echocardiographic diagnosis First, a framework of basic principles is provided with chapters on ultrasound physics, normal tomographic transthoracic and transesophageal views, intracardiac flow patterns, indications for echocardiography, and evaluation of left ventricular systolic and diastolic function A chapter on advanced echocardiographic modalities introduces the concepts of 3D echocardiography, myocardial mechanics, contrast echocardiography, and intracardiac echocardiography Clinical use of these modalities is integrated into subsequent chapters as appropriate This framework of basic principles then is built upon in subsequent chapters, organized by disease category (for example, cardiomyopathy or valvular stenosis), corresponding to the typical indications for echocardiography in clinical practice In each chapter, basic principles for echocardiographic evaluation of that disease category are reviewed, the echocardiographic approach and differential diagnosis are discussed in detail, limitations and technical considerations are emphasized, and h s tt p /: / t c a k / 9 alternate diagnostic approaches are delineated Schematic diagrams are used to illustrate basic concepts; echocardiographic images and Doppler data show typical and unusual findings in patients with each disease process Transthoracic and transesophageal images, Doppler data, and advanced imaging modalities are used throughout the text, reflecting their use in clinical practice Tables are used frequently to summarize studies validating quantitative echocardiographic methods A special feature of this book that grew out of my experience teaching fellows and sonographers is The Echo Exam section at the end of the book This section serves as a summary of the important concepts in each chapter and provides examples of the quantitative calculations used in the day-to-day clinical practice of echocardiography The information in The Echo Exam is arranged as lists, tables, and figures for clarity My hope is that The Echo Exam will also serve as a quick reference guide when a review is needed and in daily practice in the echocardiography laboratory In the fifth edition, the text of all the chapters has been revised to reflect recent advances in the field, the suggested readings have been updated, and the majority of the figures have been replaced with recent examples that more clearly illustrate the disease process The use of 3D and transesophageal imaging now is explicitly integrated into each chapter Additional tables providing clinical-echocardiographic correlation have been added to several chapters New artist drawn illustrations provide a clearer understanding of normal and abnormal cardiac anatomy Updated guidelines for the use of echocardiography and recommendations for image acquisition and analysis are summarized in tables and illustrated in figures in each chapter The online and electronic versions of the book are further enhanced by videos linked to the figures in each chapter A selected list of annotated references is included at the end of each chapter These references are suggestions for the individual who is interested in reading more about a particular subject Additional relevant articles can be found in the suggested readings Of course, an online medical reference database is the best way to obtain more recent publications and to obtain a comprehensive list of all journal articles on a specific topic For additional clinical examples, practical tips for data acquisition, and self-assessment questions, the a t r/ r i h /r u e s v vi Preface Echocardiography Review Guide, by Otto, Schwaegler, and Freeman (2nd edition, Elsevier/Saunders, 2011), parallels the information provided in this textbook and provides numerous multiple choice review questions with detailed answers A more advanced discussion of the impact of echocardiographic data in clinical medicine is available in a larger reference book, The Practice of Clinical Echocardiography, 4th edition (Otto [ed], 2012), also published by Elsevier/Saunders, with online cases, video images, and interactive multiple choice questions on the Expert Consult web site Those seeking additional expertise using echocardiography in specific clinical settings should consider the Otto Practical Echocardiography Series (Elsevier/Saunders, 2012) that includes Advanced Approaches in Echocardiography (Gillam and Otto), Intraoperative Echocardiography (Oxorn), Echocardiography in Heart Failure (St John Sutton and Wiegers), and Echocardiography in Congenital Heart Disease (Lewin and Stout) Each of these concise books provides practical clinical approaches with numerous illustrations It should be emphasized that this textbook (or any book) is only a starting point or frame of reference for learning echocardiography Appropriate training in echocardiography includes competency in the h s tt p /: / t c a k acquisition and interpretation of echocardiographic and Doppler data in real time Additional training is needed for performance of stress and transesophageal examinations Further, echocardiography continues to evolve so that as new techniques become practical and widely available, practitioners will need to update their knowledge Obviously, a textbook cannot replace the experience gained in performing studies on patients with a range of disease processes, and still photographs or selected online videos not replace the need for acquisition and review of real-time data Guidelines for training in echocardiography, as referenced in Chapter 5, serve as the standard for determining clinical competency in this technique Although this textbook is not a substitute for appropriate training and experience, I hope it will enhance the learning experience of those new to the field and provide a review for those currently engaged in the acquisition and interpretation of echocardiography Every patient deserves a clinically appropriate and diagnostically accurate echocardiographic examination; each of us needs to continuously strive toward that goal Catherine M Otto, MD /r u e s a t r/ r i h / 9 ACKNOWLEDGMENTS Many people have provided input to each edition of the Textbook of Clinical Echocardiography, and the book is immeasurably enhanced by their contributions—not all can be individually thanked here but my gratitude extends to all of you My special thanks go to the cardiac sonographers at the University of Washington for the outstanding quality of their echocardiographic examinations and for our frequent discussions of the details of image acquisition and the optimal echocardiography examination Their skill in obtaining superb images provides the basis of many of the figures in this book My thanks to Pamela Clark, RDCS; Sarah Curtis, RDCS; Caryn D’Jang, RDCS; Michelle Fujioka, RDCS; Carol Kraft, RDCS; Yelena Kovolenko, RDCS; Carol Kraft, RDCS; Chris McKenzie, RDCS; Amy Owens, RDCS; Joanna Shephard, RDCS; Becky Schwaegler, RDCS; Yu Wang, RDCS; and Todd Zwink, RDCS My gratitude extends to my colleagues at the University of Washington who shared their expertise and helped identify images for the book, including Rosario Freeman, MD; Don Oxorn, MD; Eric Krieger, MD; Steve Goldberg, MD; David Owens, MD; and Karen Stout, MD The University of Washington Cardiology Fellows also provided thoughtful (and sometimes humbling) insights with particular recognition to Jason s tt p /: / t c a k / 9 Linefsky, MD, and Elisa Zaragoza-Macias, MD In addition, my gratitude includes my colleagues from around the world who generously provided images, including Marcia Barbosa, MD, and Maria P Nunes, MD, Belo Horizonte, Brazil; and Nozomi Watanabe, MD, Kawasaki University, Okayama, Japan Appreciation is also extended to those individuals who kindly gave permission for reproduction of previously published figures Joe Chovan and Starr Kaplan are to be commended for their skills as medical illustrators and for providing such clear and detailed anatomic drawings My most sincere appreciation extends to the many readers who provided suggestions for improvement with particular thanks to Franz Wiesbauer and the participants in the 123 sonography community whose detailed input that helped shape the 5th edition of this book Many thanks to my editor at Elsevier, Dolores Meloni, for providing the support needed to write this edition, and to Joan Ryan, Brandilyn Flagg, Michael Fioretti, and the production team for all the detail-oriented hard work that went into making this book and online videos a reality Finally, my most appreciative thanks to my husband and daughter for their unwavering support in every aspect of life a t r/ r i h /r u e s h vii GLOSSARY Abbreviations Used in Figures, Tables, and Equations 2D = two-dimensional 3D = three-dimensional A-long = apical long-axis A-mode= amplitude mode (amplitude versus depth) A = late diastolic ventricular filling velocity with atrial contraction A′ = diastolic tissue Doppler velocity with atrial contraction A2C = apical two-chamber A4C = apical four-chamber AcT = acceleration time Adur = transmitral A-velocity duration adur = pulmonary vein a-velocity duration AF = atrial fibrillation AMVL = anterior mitral valve leaflet ant = anterior Ao = aortic or aorta AR = aortic regurgitation AS = aortic stenosis ASD = atrial septal defect ATVL = anterior tricuspid valve leaflet AV = atrioventricular AVA = aortic valve area AVR = aortic valve replacement BAV = bicuspid aortic valve BP = blood pressure BSA = body surface area t c a k /: / / 9 DT = deceleration time dyne · s · cm-5 = units of resistance D-TGA, complete transposition of the great arteries E = early-diastolic peak velocity E ′ = early-diastolic tissue Doppler velocity ECG = electrocardiogram echo = echocardiography ED = end-diastole EDD = end-diastolic dimension EDV = end-diastolic volume EF = ejection fraction endo = endocardium epi = epicardium EPSS = E-point septal separation ES = end-systole ESD = end-systolic dimension ESV = end-systolic volume ETT = exercise treadmill test a t r/ r i h e s /r u Δf = frequency shift f = frequency FL = false lumen Fn = near field Fo = resonance frequency Fs = scattered frequency FSV = forward stroke volume FT = transmitted frequency c = propagation velocity of sound in tissue CAD = coronary artery disease CPB = cardiopulmonary bypass cath = cardiac catheterization Cm = specific heat of tissue cm/s = centimeters per second cm = centimeters CMR = cardiac magnetic resonance imaging CO = cardiac output cos = cosine CS = coronary sinus CSA = cross-sectional area CT = computed tomography CW = continuous-wave Cx = circumflex coronary artery HCM = hypertrophic cardiomyopathy HPRF = high pulse repetition frequency HR = heart rate HV = hepatic vein Hz = Hertz (cycles per second) D = diameter DA = descending aorta dB = decibels dP/dt = rate of change in pressure over time dT/dt = rate of increase in temperature over time l = length LA = left atrium LAA = left atrial appendage LAD = left anterior descending coronary artery LAE = left atrial enlargement lat = lateral s tt p h I = intensity of ultrasound exposure IAS = interatrial septum ID = indicator dilution inf = inferior IV = intravenous IVC = inferior vena cava IVCT = isovolumic contraction time IVRT = isovolumic relaxation time kHz = kilohertz xiii xiv Glossary LCC = left coronary cusp LMCA = left main coronary artery LPA = left pulmonary artery LSPV = left superior pulmonary vein L-TGA = corrected transposition of the great arteries LV = left ventricle LV-EDP = left ventricular end-diastolic pressure LVH = left ventricular hypertrophy LVID = left ventricular internal dimension LVOT = left ventricular outflow tract M-mode = motion display (depth versus time) MAC = mitral annular calcification MI = myocardial infarction MR = mitral regurgitation MS = mitral stenosis MV = mitral valve MVA = mitral valve area MVL = mitral valve leaflet MVR = mitral valve replacement n = number of subjects NBTE = nonbacterial thrombotic endocarditis NCC = noncoronary cusp ΔP = pressure gradient P = pressure PA = pulmonary artery PAP = pulmonary artery pressure PCI = percutaneous coronary intervention PDA = patent ductus arteriosus or posterior descending artery (depends on context) PE = pericardial effusion PEP = preejection period PET = positron-emission tomography PISA = proximal isovelocity surface area PLAX = parasternal long-axis PM = papillary muscle PMVL = posterior mitral valve leaflet post = posterior (or inferior-lateral) ventricular wall PR = pulmonic regurgitation PRF = pulse repetition frequency PRFR = peak rapid filling rate PS = pulmonic stenosis PSAX = parasternal short-axis PV = pulmonary vein PVC = premature ventricular contraction PVD = pulmonary vein diastolic velocity PVR = pulmonary vascular resistance PVD = pulmonary vein diastolic velocity PWT = posterior wall thickness s tt p t c a k /: / h Q = volume flow rate Q p = pulmonic volume flow rate Q s = systemic volume flow rate r = correlation coefficient R = ventricular radius RFR = regurgitant instantaneous flow rate RA = right atrium RAE = right atrial enlargement RAO = right anterior oblique RAP = right atrial pressure RCA = right coronary artery RCC = right coronary cusp R e = Reynolds number RF = regurgitant fraction RJ = regurgitant jet R o = radius of microbubble ROA = regurgitant orifice area RPA = right pulmonary artery RSPV = right superior pulmonary vein RSV = regurgitant stroke volume RV = right ventricle RVE = right ventricular enlargement RVH = right ventricular hypertrophy RVol =regurgitant volume RVOT = right ventricular outflow tract a t r/ / 9 r i h s = second SAM = systolic anterior motion SC = subcostal SEE = standard error of the estimate SPPA = spatial peak pulse average SPTA = spatial peak temporal average SSN = suprasternal notch ST = septal thickness STJ = sinotubular junction STVL = septal tricuspid valve leaflet SV = stroke volume or sample volume (depends on context) SVC = superior vena cava e s /r u T½ = pressure half-time TD = thermodilution TEE = transesophageal echocardiography TGA = transposition of the great arteries TGC = time-gain compensation Th = wall thickness TL = true lumen TN = true negatives TOF = tetralogy of Fallot TP = true positives TPV = time to peak velocity TR = tricuspid regurgitation TS = tricuspid stenosis TSV = total stroke volume TTE = transthoracic echocardiography TV = tricuspid valve v = velocity V = volume or velocity (depends on context) VAS = ventriculo-atrial septum Veg = vegetation Vmax = maximum velocity VSD = ventricular septal defect VTI = velocity-time integral WPW = Wolff-Parkinson-White syndrome Z = acoustic impedance Glossary Symbols Greek Name Used for Variable Unit α alpha Frequency Mass g γ gamma Viscosity Grams Example: LV mass Δ delta Difference Pressure mm Hg θ theta Angle λ lambda Wavelength μ mu Micro- Millimeters of mercury, mm Hg = 1333.2 dyne/cm2, where dyne measures force in cm-mg-s2 π pi Mathematical constant (approx 3.14) ρ rho Tissue density σ sigma Wall stress τ tau Time constant of ventricular relaxation Variable Unit Definition Amplitude dB Decibels = a logarithmic scale describing the amplitude (“loudness”) of the sound wave Angle degrees Degree = (π/180)rad Example: intercept angle Area cm2 s tt p Frequency (f) Hz kHz MHz h Length t c a k Square centimeters A 2D measurement (e.g., end-systolic area) or a calculated value (e.g., continuity equation valve area) /: / Hertz (cycles per second) Kilohertz = 1000 Hz Megahertz = 1,000,000 Hz cm Centimeter (1/100 m) mm Millimeter (1/1000 m or 1/10 cm) / 9 Resistance dyne · s · cm-5 Measure of vascular resistance Time s ms μs Ultrasound intensity W/cm2 Velocitytime integral (VTI) e s /r u Volume mW/cm2 a t r/ Velocity (v) UNITS OF MEASURE Definition m/s cm/s cm cm3 mL L Volume flow rate (Q) L/min mL/s Wall stress dyne/cm2 kdyn/cm2 kPa Second Millisecond (1/1000 s) Microsecond r i h Where watt (W) = joule per second and joule = m2 · kg · s-2 (unit of energy) Meters per second Centimeters per second Integral of the Doppler velocity curve (cm/s) over time (s), in units of cm Cubic centimeters Milliliter, mL = cm3 Liter = 1000 mL Rate of volume flow across a valve or in cardiac output L/min = liters per minute mL/s = milliliters per second Units of meridional or circumferential wall stress Kilodynes per cm2 Kilopascals where kPa = 10 kdyn/cm2 xv KEY EQUATIONS / 9 Ultrasound Physics f = cycles/s = Hz Frequency λ = c / f = 1.54/f (MHz) Wavelength υ = c × Δf/ [2FT (cosθ)] Doppler equation ΔP = 4V Bernoulli equation LV Imaging SV = EDV − ESV Stroke volume EF( % ) = (SV / EDV) × 100 % Ejection fraction σ = PR/2Th Wall stress Doppler Ventricular Function SV = CSA × VTI Stroke volume dP/dt = 32 mm Hg / time from to m/s of MR CW jet(sec) Rate of pressure rise MPI = (IVRT + IVCT) / SEP Myocardial performance index Pulmonary Pressures and Resistance PAPsystolic = 4(VTR )2 + RAP Pulmonary systolic pressure PAPsystolic = [4(VTR )2 + RAP] − Δ PRV − PA PAP (when PS is present) PAPmean = Mean Δ PRV − RA + RAP Mean PA pressure PAPdiastolic = 4(VPR )2 + RAP Diastolic PA pressure PVR ≅ 10(VTR )/VTIRVOT Pulmonary vascular resistance Aortic Stenosis Δ Pmax = 4(Vmax )2 Maximum pressure gradient (integrate over ejection period for mean gradient) AVA(cm2 ) = [π(LVOTD / 2)2 × VTILVOT ] / VTIAS-Jet Continuity equation valve area AVA(cm2 ) = [π(LVOTD / 2)2 × VLVOT ] / VAS-Jet Simplified continuity equation Velocity ratio = VLVOT /VAS-Jet Velocity ratio Mitral Stenosis MVADoppler = 220 / T½ Pressure half-time valve area Aortic Regurgitation TSV = SVLVOT = (CSALVOT × VTILVOT ) Total stroke volume FSV = SVMA = (CSAMA × VTIMA ) Forward stroke volume RVol = TSV − FSV Regurgitant volume ROA = RSV / VTIAR Regurgitant orifice area Mitral Regurgitation TSV = SVMA = (CSAMA × VTIMA ) Total stroke volume (or 2D or 3D LV stroke volume) FSV = SVLVOT = (CSALVOT × VTILVOT ) Forward stroke volume RVol = TSV − FSV Regurgitant volume ROA = RSV/VTIAR Regurgitant orifice area PISA method RFR = 2πr2 × Valiasing Regurgitant flow rate ROAmax = RFR / VMR Orifice area (maximum) RV = ROA × VTIMR Regurgitant volume Aortic Dilation Predicted sinus diameter Children (40 years): Predicted sinus dimension = 1.92 + (0.74 BSA) Ratio = Measured maximum diameter / Predicted maximum diameter Pulmonary (Q p) to Systemic (Q s) Shunt Ratio Q p : Q s = [CSAPA × VTIPA ] / [CSALVOT × VTILVOT ] s tt p t c a k a t r/ r i h /r u e s /: / h xvii Cardiomyopathies, Hypertensive and Pulmonary Heart Disease  |  Chapter LV LV RV Ao RA LA LA Figure 9–25  Amyloidosis Apical four-chamber (left) and two-chamber (right) 2D echocardiographic images in a patient with a restrictive cardiomyopathy due to amyloidosis There is biventricular hypertrophy, biatrial enlargement, and both systolic and diastolic dysfunction of the LV Mild, diffuse valve thickening also is present Ao, aorta echocardiography) Thrombus formation also occurs under the posterior mitral valve leaflet, which leads to adherence of the posterior leaflet to the endocardium and significant mitral regurgitation Heart disease related to radiation therapy results in a restrictive cardiomyopathy of both the LV and the RV and in accelerated calcific valve disease and coronary atherosclerosis of the segments within the radiation field Diastolic Function LV RV RA LA Figure 9–26  Fabry disease The apical four-chamber view in this 48 year-old-man with Fabry disease shows increased LV wall thickness with increased echodensity of the endocardium, particularly along the septum (arrows) The pattern of LV diastolic filling parallels the abnormalities in LV diastolic function in this disease However, interpretation is complicated both by the numerous confounding factors that affect LV diastolic filling (see Chapter 7) and by temporal changes in diastolic filling as the disease progresses in an individual patient Early in the disease course, impaired diastolic relaxation of the LV results in impaired early-diastolic filling The Doppler LV inflow curve shows a reduced E velocity, increased A velocity, prolonged isovolumic relaxation time, and decreased early-diastolic deceleration slope The mitral annular tissue Doppler signal shows a reduced E ′ and increased A′ velocity (Fig 9-27) The pulmonary vein flow curve shows a reduced diastolic filling phase and normal systolic filling phase, which results in a decreased ratio of systolic to diastolic pulmonary venous flow 239 240 Chapter 9  |  Cardiomyopathies, Hypertensive and Pulmonary Heart Disease E A the LV at mitral valve opening Along with reduced diastolic compliance of the LV, this increased mitral opening pressure leads to an increased E velocity and a rapid deceleration slope The A velocity is reduced because of a combination of increased LV end-­ diastolic pressure and reduced atrial contractile function Thus the pattern of diastolic filling in established restrictive cardiomyopathy (which may coincide with the initial clinical presentation) is similar to the “big E, little A” pattern seen in normal young individuals However, this “pseudonormal” pattern of LV filling can be distinguished from normal by:    n n n n    SЈ EЈ AЈ Figure 9–27  Diastolic function in restrictive cardiomyopathy LV diastolic filling in a patient with a restrictive cardiomyopathy shows pseudonormalization with an E velocity slightly greater than the A velocity (top) This pattern is distinguished from normal by the tissue Doppler myocardial velocity (bottom) showing reduced early motion (E′), compared to the motion after atrial contraction (A′) RA filling patterns, recorded in the hepatic vein (or superior vena cava), correspond to physical examination of the neck vein pulsations seen in patients with restrictive cardiomyopathy Using this analogy, the hepatic vein flow pattern typically shows:    n n n     prominent reverse flow phase with atrial conA traction (a-wave) A rapid filling curve in systole (x-descent) A blunted RA diastolic filling phase (diminished v-wave and y-descent) These findings correspond to the pattern of RA pressure recordings at catheterization; the x-descent represents the “dip,” and the blunted systolic filling phase represents the “plateau” of the dip-and-plateau pattern As the disease progresses, LA pressure rises, resulting in an increased pressure gradient from the LA to  he rapid early-diastolic deceleration time (LV T inflow) A reduced E ′ velocity (annular tissue velocity) An increased PVa velocity and duration The patient’s age, clinical presentation, and other associated echocardiographic findings With a pseudo normal LV inflow pattern, mitral annular velocity shows a marked reduction in E′ velocity with the ratio of transmitral E velocity to annular E′ velocity corresponding to the elevation in LV end-diastolic pressure In addition, pulmonary venous inflow in diastole is normal or increased as blood flows in a conduit from the pulmonary veins to LV With atrial contraction, the increased resistance to LV filling results in an increase in the velocity and duration of the atrial flow reversal into the lower resistance pulmonary veins Thus, pulmonary venous flow shows an increased diastolic phase, reduced systolic phase, and prominent a-wave flow reversal This is in contrast to the normal pattern of nearly equal systolic and diastolic pulmonary venous inflow curves and a small a-wave Late in the disease course, a restrictive pattern of LV filling is seen with an increased E velocity and reduced A velocity, steep early-diastolic deceleration slope, and reduced isovolumic relaxation time Limitations and Technical Considerations Differentiation between restrictive cardiomyopathy and constrictive pericarditis is problematic Both have a similar clinical presentation, and both are characterized by preserved LV systolic function with impaired diastolic filling Features that distinguish these two conditions include the patterns of atrial and ventricular diastolic filling, the presence or absence of pericardial thickening, and the degree of associated pulmonary hypertension However, no single feature is diagnostic of either condition (see Table 10-2) Attention to technical details is necessary in recording Doppler atrial and ventricular filling patterns, particularly attention to their relationship to the phase of respiration (see Chapter 7) Respiratory variation is assessed most reliably using a respirometer to mark the onsets of inspiration and expiration Before recording Doppler signals, 2D and color flow imaging is used to Cardiomyopathies, Hypertensive and Pulmonary Heart Disease  |  Chapter convince the sonographer that there is no significant respiratory variation in the angle between the ultrasound beam and direction of blood flow, since respiratory changes in intercept angle could result in apparent changes in velocity, even under constant-flow conditions, due to the erroneous assumption that cosine θ remains in the Doppler equation Clinical Utility In a patient with symptoms of heart failure, a diagnosis of restrictive cardiomyopathy may not have been suspected on clinical grounds In some cases, echocardiographic findings may provide the first clues pointing toward this diagnostic possibility In a patient with known restrictive cardiomyopathy, echocardiography can be used to follow disease progression A meticulous examination with careful attention to technical details and with integration of imaging, Doppler and clinical data may allow differentiation between restrictive cardiomyopathy and constrictive pericarditis Alternate Approaches Clinical history and laboratory tests are important in determining the cause of a restrictive cardiomyopathy Diagnostic evaluation also may include cardiac catheterization with measurement of intracardiac pressures at rest and with volume loading Endomyocardial biopsy can be diagnostic, although sensitivity is low because of nonhomogeneous myocardial involvement in many of these conditions Biopsy of noncardiac tissue may be diagnostic for amyloidosis Chest computed tomographic imaging can exclude pericardial calcification or thickening Cardiac magnetic resonance imaging can detect myocardial iron overload due to hemochromatosis or patchy late gadolinium enhancement with sarcoidosis and can distinguish myocardial involvement due to restrictive cardiomyopathy from constrictive pericarditis OTHER CARDIOMYOPATHIES Arrhythmogenic Right Ventricular Dysplasia (ARVD) Arrhythmogenic RV dysplasia (ARVD) is a genetic form of cardiomyopathy that results in fibrofatty replacement of the RV wall and clinical manifestations of RV systolic dysfunction, arrhythmias, and sudden death Echocardiographic findings include RV dilation and systolic dysfunction in the presence of a relatively normal LV and normal pulmonary pressures (Fig 9-28) Prominent trabeculation of the RV, increased echogenicity of the moderator band, and small RV aneurysms also may be seen However, echocardiographic findings are quite variable and other imaging approaches, such as cardiac LV RV RA LA Figure 9–28  Arrhythmogenic RV dysplasia In this patient with a history of resuscitated sudden death, the apical four-chamber view shows only mild RV dilation and systolic dysfunction, but there is an abnormal contour of the RV free wall magnetic resonance imaging, may be more accurate for this diagnosis Left Ventricular Noncompaction Isolated LV noncompaction is a genetic cardiomyopathy characterized by decreased coronary flow reserve and a thickened, prominently trabeculated myocardium with deep recesses that communicate with the ventricular chamber (Fig 9-29) A similar pattern of ventricular trabeculation may be seen with secondary cardiomyopathies due to neuromuscular diseases and other conditions Features of noncompaction overlap with the clinical presentation of dilated, hypertrophic and restrictive cardiomyopathy Noncompaction presents clinically with heart failure, embolic events, and arrhythmias Distinguishing echocardiographic features are hypokinesis and myocardial thickening localized to the apex, mid-lateral, and mid-inferior walls; a ratio of the thickness of the noncompacted to compacted myocardium at end-systole ≥ 2:1; and color Doppler showing flow extending into the trabecular recesses ADVANCED HEART FAILURE THERAPIES Cardiac Resynchronization Therapy Variability in the timing of myocardial contraction between different LV segments, or dyssynchrony, is evident on 2D imaging in many patients with heart failure; it can be quantitated with 3D wall motion 241 242 Chapter 9  |  Cardiomyopathies, Hypertensive and Pulmonary Heart Disease pacer therapy to resynchronize the pattern of contraction However, clinical trials not yet support the use of dyssynchrony measures; instead resynchronization therapy is recommended in patients with heart failure and significant symptoms, a wide QRS (over 120 ms), and an LV ejection fraction 35% or less Left Ventricular Assist Devices (LVADs) RV LV RA LA A Mechanical support with an LV assist device (LVAD) (Fig 9-30) can be used to maintain a normal cardiac output in patients with acute heart failure until myocardial recovery occurs or until the patient can receive a heart transplantation An LVAD also may be used as destination therapy for long-term support where recovery or transplantation is not likely to occur Echocardiographic evaluation of patients with an LVAD is challenging, in part because current devices provide continuous rather than pulsatile flow, with blood intake into the device from a cannula at the LV apex, with blood pumped back into the ascending aorta Imaging shows severe LV systolic dysfunction In addition, the aortic valve may remain closed throughout the cardiac cycle because blood is pumped from the LV to the aorta without crossing the valve Flow patterns and expected velocity data vary between devices (see Suggested Readings 28, 30, and 31), but changes between studies often are most important in clinical decision making In addition to standard imaging as in any patient with heart failure, recommended parameters for echocardiographic evaluation of a patient with an LVAD include:    n n LV n n n    B Figure 9–29  LV noncompaction The apical four-chamber view (A) shows the thick LV wall with deep trabecular recesses (arrow) The color flow image (B) shows ventricular flow filling the trabeculated sections of the myocardium analysis or with tissue Doppler or speckle tracking echocardiography Dyssynchrony in the timing of RV and LV contraction also can be evaluated using M-mode or spectral Doppler approaches It is plausible that measurement of mechanical dyssynchrony (rather than electrical dyssynchrony as seen on ECG) should identify which patients might benefit from  ecord LVAD type, mode, and pump speed R Measure LV dimensions and volumes in standard image planes Record aortic valve motion with M-mode for several cardiac cycles to document aortic valve opening frequency and duration Record LVAD inflow from the apical conduit using color and pulsed Doppler Record LVAD outflow into the ascending aorta with color and pulsed Doppler Optimal images of the inflow and outflow cannulas often require oblique nonstandard image plans Echocardiographic data may be used to optimize LVAD flow parameters to avoid underfilling the device, resulting in either low forward flow rates and a dilated ventricle or excessively high flow rates, which can result in cannula obstruction due to a small LV chamber impinging on the inflow cannula orifice Complications that can be detected include pericardial tamponade (often loculated), RV failure, and thrombus formation Total Artificial Heart Echocardiographic evaluation of patients with a total artificial heart is limited because the pumping Cardiomyopathies, Hypertensive and Pulmonary Heart Disease  |  Chapter Outflow cannula Inflow cannula LV assist device Figure 9–30  LV assist device Example of a continuous flow LV assist device with low velocity inflow recorded from the apical cannula and outflow recorded in the ascending aorta The aortic valve remains closed throughout systole on most beats with this type of LV assist device chambers of the artificial heart are plastic and not allow acoustic access On transthoracic imaging, RA filling pressures can be estimated from the appearance of the inferior vena cava, but other images usually cannot be obtained On TEE imaging, views are limited to visualization of the RA and LA, along with the atrioventricular mechanical valves Cardiac Allograft Structure and Function Common problems encountered in patients after cardiac transplantation include:    n n Cardiac Transplantation Echocardiographic evaluation of a patient after cardiac transplantation typically is directed toward one of three goals: (1) assessment of cardiac anatomy and physiology prompted by a specific clinical problem, (2) the elusive goal of noninvasive diagnosis of early rejection of the transplanted heart, or (3) diagnosis of posttransplant coronary artery disease n     ericardial effusion, particularly early postoperaP tively RV systolic dysfunction due to inadequate myocardial preservation at the time of transplantation, persistently elevated pulmonary vascular resistance, or transplant rejection LV systolic dysfunction due to inadequate myocardial preservation, acute rejection early after transplantation, or superimposed coronary artery disease at a longer interval after transplantation Primary valvular disease, of course, is uncommon because of screening of donor hearts before 243 244 Chapter 9  |  Cardiomyopathies, Hypertensive and Pulmonary Heart Disease transplantation However, mitral or tricuspid regurgitation secondary to ventricular dysfunction and annular dilation may be seen Diastolic dysfunction is an early marker of rejection Typically, RV and LV size, wall thickness, and systolic function are normal in the absence of perioperative complications or rejection However, abnormal septal motion, with anterior motion of the septum in systole with a slight decrease in the extent of systolic thickening of the septal myocardium, is the norm Valvular anatomy and function are normal, with small amounts of mitral, tricuspid, and pulmonic regurgitation present with a prevalence similar to that in normal individuals The suture lines in the aorta and pulmonary artery may be difficult to appreciate depending on the distance of the suture lines from the valve planes and the type of surgical procedure A small pericardial effusion is seen early in the postoperative period but rarely persists beyond a few weeks Pericardial effusions often are loculated because of postoperative pericardial adhesions, so examination in multiple tomographic planes from parasternal, apical, and subcostal windows is essential when this diagnosis is suspected Pulmonary artery pressures may show some degree of persistent elevation as calculated from the velocity in the tricuspid regurgitant jet and estimates of RA pressure If the surgical approach included anastomoses of the normal and donor atrium, a normal echocardiogram after cardiac transplantation will show biatrial enlargement (Fig 9-31) with a variably prominent ridge between the donor and recipient portions of both the RA and LA The atrial suture line should not be mistaken for an abnormal atrial mass When transplantation is performed with anastomosis of the superior and inferior vena cavae for the RA and a cuff of tissue with the pulmonary veins for the LA, there is little atrial enlargement, and suture lines may not be evident Figure 9–31  Post-heart–transplant Comparison of the echocardiographic appearance of cardiac allografts transplanted by the biatrial (A) versus bicaval techniques (B) In comparison with the bicaval technique, the biatrial technique results in much larger atria Prominent suture lines are visible (arrows).  (From Wu AH, Kolias TJ: Cardiac transplantation: Pre and post transplant evaluation In Otto CM [ed]: The Practice of Clinical Echocardiography, 4th ed Philadelphia: Saunders, 2012, Fig 30-3.) RV Acute Transplant Rejection With acute, severe rejection, echocardiography shows increased LV mass, decreased systolic function, and an increase in the echogenicity of the myocardium However, with mild or early rejection, echocardiographic changes are subtle and are not accurate or reproducible enough to allow adjustment of immunosuppressive medications in individual patients Instead, proposed approaches to the diagnosis of early rejection have focused on measures of diastolic function, specifically measures of early-diastolic relaxation The Doppler changes in acute rejection include:    n n n     ecreased pressure half-time (increased earlyD diastolic deceleration slope) Decreased isovolumetric relaxation time Increased E velocity Compared to the patient’s own baseline study, a significant change (defined as >20% for E velocity and >15% for pressure half-time or isovolumic relaxation time) is consistent with rejection Tissue Doppler measures are sensitive but not specific for the detection of rejection In addition, many posttransplant patients have resting tachycardia, with E/A fusion, due to cardiac denervation Some transplant centers have found these measures clinically useful, but most centers continue to rely on endomyocardial biopsy Post-Transplant Monitoring As survival after cardiac transplantation has improved, increasing numbers of patients are seen with posttransplant coronary artery disease Transplant coronary disease differs from typical atherosclerosis in that both epicardial vessels and the microvasculature are diffusely involved with an accelerated form of intimal hyperplasia Echocardiographic exercise stress testing has a higher prevalence of false-negative results because of the diffuse disease process masking regional LV RV RA LA RA A LV B LA Cardiomyopathies, Hypertensive and Pulmonary Heart Disease  |  Chapter wall motion abnormalities Dobutamine stress echocardiography is more accurate in this patient population and now is routine at many transplant centers However, coronary angiography may be needed for a definitive diagnosis, often with concurrent intravascular ultrasound examination of the coronary arteries Limitations, Technical Considerations, and Alternate Approaches The standard method for the evaluation of transplant rejection remains transvenous endomyocardial biopsy Some centers use echocardiographic (rather than fluoroscopic) guidance for this procedure Because echocardiographic images are tomographic, any segment of the biopsy catheter going through the image plane will appear to be the “tip.” Thus it is crucial to identify the open forceps at the tip for correct identification of the biopsy site A subcostal window often is most practical because, with the patient supine, clear views of the RV and septum are obtained, and the sonographer is clear of the sterile field (usually the right internal jugular vein approach is used) In some cases, the apical view also may be helpful HYPERTENSIVE HEART DISEASE Basic Principles Hypertensive heart disease is an end-organ consequence of systemic hypertension Chronic systemic pressure overload results in LV hypertrophy to maintain normal wall stress Initially diastolic function is impaired, while systolic function remains normal With long-standing hypertension, systolic dysfunction and ventricular dilation can occur Typical echocardiographic findings associated with chronic hypertension include: thickness (>11 mm) LV mass can be estimated from M-mode data, assuming hypertrophy is symmetric, but preferably is calculated from 2D data (see Chapter 6) Diastolic Function LV diastolic function is characterized by impaired early-diastolic relaxation (Fig 9-33) This results in a prolonged isovolumic relaxation time, reduced acceleration to a reduced E velocity, prolonged early-diastolic deceleration slope, an increased A velocity, and an E/A ratio 50 mm Hg was present at rest in 37% of subjects Exercise stress testing in the remaining 201 patients demonstrated provocable obstruction in 106 (33% of total) Only 95 patients (30% of total) had nonobstructive disease with a gradient 2.0 cm was seen in those with apical hypertrophic cardiomyopathy 11 Geske JB, Sorajja P, Nishimura RA, et al: Evaluation of left ventricular filling pressures by Doppler echocardiography in patients with hypertrophic cardiomyopathy: Correlation with direct left atrial pressure measurement at cardiac catheterization Circulation 116(23):2702-2708, 2007 In 100 patients with symptomatic hypertrophic cardiomyopathy, Doppler data were compared to directly measured LA pressures, with simultaneous measurements in 42 subjects Although the Doppler E/E′ ratio statistically correlated with directly measured LA pressure, there was marked scatter in the data with wide 95% confidence limits of ± 18 mm Hg These finding suggest that noninvasive estimates of LV filling pressures are not accurate in patients with hypertrophic cardiomyopathy, which is likely related to the multiple factors affecting diastolic function in these patients 12 Abergel E, Chatellier G, Hagege AA, et al: Serial left ventricular adaptations in world-class professional cyclists: Implications for disease screening and follow-up J Am Coll Cardiol 44(1):144149, 2004 This study compared 286 cyclists who had participated in the Tour de France race with 52 sedentary controls Over 50% of high-level endurance athletes had LV dilation (diastolic dimension >60 mm) and about 12% had a reduced (

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