Senior Acquisitions Editor: Sonya Seigafuse Senior Product Manager: Kerry Barrett Production Manager: Bridgett Dougherty Senior Manufacturing Manager: Benjamin Rivera Senior Marketing Manager: Kimberly Schonberger Design Coordinator: Terry Mallon Production Service: SPi Global Copyright © 2012 by LIPPINCOTT WILLIAMS & WILKINS, a WOLTERS KLUWER business Two Commerce Square 2001 Market Street Philadelphia, PA 19103 USA LWW.com All rights reserved. This book is protected by copyright. No part of this book may be reproduced in any form by any means, including photocopying, or utilized by any information storage and retrieval system without written permission from the copyright owner, except for brief quotations embodied in critical articles and reviews. Materials appearing in this book prepared by individuals as part of their official duties as U.S. government employees are not covered by the above-mentioned copyright. Printed in China Library of Congress Cataloging-in-Publication Data Thaler, Malcolm S. The only EKG book you’ll ever need / Malcolm S. Thaler. — 7th ed. p. ; cm. Includes index. ISBN 978-1-4511-1905-3 I. Title. [DNLM: 1. Electrocardiography. 2. Heart Diseases—diagnosis. WG 140] 616.1’207547—dc23 2011041429 Care has been taken to confirm the accuracy of the information presented and to describe generally accepted practices. However, the authors, editors, and publisher are not responsible for errors or omissions or for any consequences from application of the information in this book and make no warranty, expressed or implied, with respect to the currency, completeness, or accuracy of the contents of the publication. Application of the information in a particular situation remains the professional responsibility of the practitioner. The authors, editors, and publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accordance with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any change in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new or infrequently employed drug. Some drugs and medical devices presented in the publication have Food and Drug Administration (FDA) clearance for limited use in restricted research settings. It is the responsibility of the health care provider to ascertain the FDA status of each drug or device planned for use in their clinical practice. To purchase additional copies of this book, call our customer service department at (800) 638-3030 or fax orders to (301) 223-2320. International customers should call (301) 223-2300. Visit Lippincott Williams & Wilkins on the Internet: at LWW.com. Lippincott Williams Wilkins customer service representatives are available from 8:30 am to 6 pm, EST. 10987654321 Dedication To Nancy, Ali, and Jon—of course Preface New content! New cases! New color! New clinical pearls! Yet even as we keep adding, changing, and improving, the fundamentals remain. It’s been about 25 years since the first edition of this little book, and we have remained resolute to the principles outlined in that very first preface: This book is about learning. It’s about keeping simple things simple and complicated things clear, concise and, yes, simple, too. It’s about getting from here to there without scaring you to death, boring you to tears, or intimidating your socks off. It’s about turning ignorance into knowledge, knowledge into wisdom, and all with a bit of fun. We must be doing something right, because each year The Only EKG Book You Will Ever Need becomes more popular, more widely translated, and adopted and used in more medical and other professional schools. This edition offers a host of revisions and refinements: A whole new palette of colors to make the models, illustrations, and tracings clearer than ever New clinical cases to expand on one of the most important distinctions of the book: to put everything into its proper clinical context (you are put right into the middle of real-life clinical situations) and to make the information usable Expanded sections on subjects where new developments have made deeper understanding possible, including atrial fibrillation, long QT syndrome, apical ballooning syndrome, and others Greater clarity where it is called for, new tracings where they help illuminate the points we are trying to make, and—wherever possible— shortening and simplifying As ever, hats off to Glenn Harper, M.D., the world’s greatest cardiologist, whose help was invaluable in ensuring the text is up-to-date, clear, and accurate. And remove two more hats for Kerry Barrett and Sonya Seigafuse, who continue to lead the Lippincott Williams & Wilkins team that—year after year, edition after edition—produces the best-looking, most readable EKG book that one could hope for. To those of you who are picking up this book for the first time and for those of you who are making a return visit, I hope The Only EKG Book You Will Ever Need will provide you with everything you need to read EKGs quickly and accurately. Malcolm Thaler, M.D. Contents Getting Started Chapter 1 The Basics Electricity and the Heart The Cells of the Heart Time and Voltage P Waves, QRS Complexes, T Waves, and Some Straight Lines Naming the Straight Lines Summary: The Waves and Straight Lines of the EKG Making Waves The 12 Views of the Heart A Word About Vectors The Normal 12-Lead EKG Summary: Orientation of the Waves of the Normal EKG Coming Attractions Chapter 2 Hypertrophy and Enlargement of the Heart Definitions Axis Summary: Axis Axis Deviation, Hypertrophy, and Enlargement Atrial Enlargement Summary: Atrial Enlargement Ventricular Hypertrophy Secondary Repolarization Abnormalities of Ventricular Hypertrophy Summary: Ventricular Hypertrophy CASE 1 CASE 2 Chapter 3 Arrhythmias The Clinical Manifestations of Arrhythmias Why Arrhythmias Happen Rhythm Strips How to Determine the Heart Rate From the EKG The Five Basic Types of Arrhythmias Arrhythmias of Sinus Origin Ectopic Rhythms Reentrant Rhythms The Four Questions Supraventricular Arrhythmias Summary: Supraventricular Arrhythmias Ventricular Arrhythmias Summary: Ventricular Arrhythmias Supraventricular Versus Ventricular Arrhythmias Summary: Ventricular Tachycardia (VT) Versus PSVT With Aberrancy Programmed Electrical Stimulation Implantable Defibrillators External Defibrillators CASE 3 CASE 4 CASE 5 Chapter 4 Conduction Blocks What Is a Conduction Block? AV Blocks Summary: AV Blocks Bundle Branch Block Summary: Bundle Branch Block Hemiblocks Combining Right Bundle Branch Block and Hemiblocks Blocks That Underachieve The Ultimate in Playing With Blocks: Combining AV Blocks, Right Bundle Branch Block, and Hemiblocks Pacemakers CASE 6 CASE 7 Chapter 5