Quick and Accurate 12-Lead ECG Interpretation DALE DAVIS, RCT Illustrated by Patrick Turner, Leslie Foster-Roesler and Deborah Lynam Quick and Accurate(cid:3) 12-Lead ECG(cid:3) Interpretation Fourth Edition Acquisitions Editor:Patricia Casey Editorial Assistant:Katherine Rothwell Senior Production Editor:Tom Gibbons Director of Nursing Production:Helen Ewan Managing Editor / Production:Erika Kors Design Coordinator:Brett MacNaughton Cover Designer: Rosemary Murphy Interior Designer:BJ Crim Senior Manufacturing Manager:William Alberti Indexer:Manjit Sahai Compositor:Techbooks Printer: R. R. Donnelley Fourth Edition Copyright © 2005 by Lippincott Williams & Wilkins. Copyright © 2001 by Lippincott Williams & Wilkins. Copyright © 1992, 1985 by J. B. Lippincott Company. All rights reserved. This book is protected by copyright. No part of it may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means—electronic, mechanical, photocopy, recording, or otherwise—without prior written permission of the publisher, except for brief quotations embodied in critical articles and reviews and testing and evaluation materials provided by publisher to instructors whose schools have adopted its accompanying textbook. Printed in the United States of America. For information write Lippincott Williams & Wilkins, 530 Walnut Street, Philadelphia, PA 19106. 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. 9  8  7  6  5  4  3  2  1 Library of Congress Cataloging-in-Publication Data Davis, Dale. Quick and accurate 12-lead ECG interpretation / Dale Davis—4th ed. p. ; cm. Includes bibliographical references and index. ISBN 1-58255-379-3 (pbk. : alk. paper) 1. Electrocardiography—Interpretation.  2. Heart—Diseases—Diagnosis.  I. Title. [DNLM:   1. Electrocardiography—methods—Handbooks.  2. Electrocardiography— methods— Programmed Instruction.  3. Heart—Diseases—diagnosis—Handbooks.  4. Heart Diseases— diagnosis—Programmed Instruction. WG 18.2 D261q  2004] RC683.5.E5D33  2004 616.1(cid:0)207547—dc22 2004013921 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, express or implied, with respect to the content of the publication. 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 this publication have Food and Drug Administration (FDA) clearance for limited use in restricted research settings. It is the responsibil- ity of the health care provider to ascertain the FDA status of each drug or device planned for use in his or her clinical practice. LWW.com REVIEWERS Elisabeth G. Bradley, RN, APN, CCRN Clinical Nurse Specialist, Critical Care/Medical Cardiology Christiana Care Health System Christiana Hospital Newark, Delaware Ginger S. Braun, RN, MSN, CCRN Cardiovascular Clinical Nurse Specialist Hoag Hospital Newport Beach, California Janice M. Judy, RN, MSN Instructor University of Nebraska Medical Center, College of Nursing, West Nebraska Division Scottsbluff, Nebraska Marge Lantz Assistant Director ICU/NICU/NSD Hinsdale Hospital Hinsdale, Illinois Gayla P. Smith, RN, MS, CCRN Cardiovascular Clinical Nurse Specialist Hoag Hospital Newport Beach, California Nan Smith-Blair Assistant Professor of Nursing University of Arkansas Fayetteville, Arkansas v PREFACE Quick and Accurate 12-Lead ECG Interpretationis designed as an easy yet comprehensive approach to basic ECG and arrhythmia interpretation. Its easy-to-understand program can be used not only for quick and comprehensive learning but also as a reference and a study guide. Chapters 1 through 9 cover the fundamental knowledge necessary to evaluate normal 12-lead ECGs. Chapters 10 though 13 cover the specialized criteria necessary to interpret abnormal 12-lead ECGs. Chapters 14 and 15 allow students to practice and sharpen their newly acquired ECG interpretation skills. Chapter 16 is an introduction to basic arrhythmia interpretation. New to this edition are the inclusion of 20 new strips in Chapter 16 to help clarify arrhythmia interpretation even further and the addition of Chapter 17. This new chapter allows the students to practice their arrhythmia interpretation skills on 25 arrhythmia strips and check their answers at the end of the chapter. This book teaches students via a simply organized step-by-step process. It includes easy-to-understand diagrams that enhance the text and assure comprehension of the electrophysiology of normal and abnormal ECGs and arrhythmias rather than just memorization of criteria. I have intentionally chosen simplicity over exactness in some areas of the book in order to make learning uncomplicated. A summary of each ECG abnormality discussed in Chapters 10 to 13 is pre- sented in a two-page display toward the end of these chapters and is divided into three parts: 1. A diagram of the heart demonstrates the ECG abnormality, with the ECG leads necessary for examination placed around the heart in their correct positions. 2. Criteria necessary for recognition of the abnormality are listed directly below the heart diagram. 3. A 12-lead ECG that is representative of the ECG abnormality is displayed on the opposite page, with the previously designated leads vii observed around the heart diagram and in the criteria section tinted in blue for final correlation. Practice ECGs with answers comprising interpretations that relate only to the topic discussed in the chapter are included at the end of each ECG abnormality chapter. These ECGs are designed to reinforce the one concept just learned, without students having to concern themselves with other abnormalities. Chapter 14 is devoted to differential diagnosis and presents an easy and organized step-by-step guide to ECG interpretation. The criteria for the ECG abnormalities are examined individually and compared with one another to demonstrate possible identification problems and to give sugges- tions and hints for easier solutions. The most common interpretation pitfalls are discussed and demonstrated. Chapter 15 comprises ECGs and answers consisting of interpretations of assorted abnormalities. These are to be interpreted by students after completing the book since they will now be able to make differential diagnoses using all the knowledge gained. Chapter 16 is an introduction to basic arrhythmias rather than an exhaustive study of the subject. Each arrhythmia is presented with a list of criteria for recognition, a diagram of the electrical conduction system with the respective abnormality depicted, and numerous representations of the arrhythmia. New to this edition are additional arrhythmia strips that are identified and labeled to aid the student in becoming familiar with the abnormality. For the fourth edition, Chapter 17 has been added. This chapter adds twenty-five practice arrhythmia strips with answers at the end of the chap- ter. This addition will allow students to test their newly gained arrhythmia interpretative skills. Quick and Accurate 12-Lead ECG Interpretationis directed toward students in the allied health, nursing, or medical fields who desire the ability to interpret both routine and abnormal ECGs and to be able to assess and accurately interpret arrhythmias. Reading the text and interpreting the ECGs at the end of Chapter 15 will enable readers both to interpret ECGs skillfully and rapidly and to understand the electrophysiology of normal and abnormal ECG patterns. Reading Chapter 16 will allow students to interpret arrhythmia strips and also understand the electrophysiology behind each arrhythmia. Chapter 17 will enable students to hone their skills and check the accuracy of their interpretation. PREFACE viii The intention and scope of this fourth edition are unchanged from previous editions; simplicity and an organized interpretive method remain the central themes. I am most appreciative of the positive response to this book, and I hope that the changes and the addition of additional arrhythmia strips will make learning easier and more effective. Dale Davis PREFACE ix ACKNOWLEDGMENTS It’s hard to believe that I’m on my fourth edition of Quick and Accurate 12-Lead ECG Interpretation,almost 10 years after the book first was published. I am grateful to my publisher, Lippincott Williams & Wilkins, for allowing me great freedom both in the layout of this book and in the reproduction of the ECG strips. My thanks to Lisa A. Biello, my first editor, for her enthusiasm and encouragement she gave me in producing my first book. Many thanks to my illustrator, Patrick Turner, for his creativity and for his patience with my often-confusing instructions. And thanks to my current editor, Patricia Casey, for her help with this fourth edition. I received assistance with my interpretive skills from the medical staff at Morristown Memorial Hospital, Morristown, New Jersey. I want to specifically thank Doctors Stelio Mangiola, Joel Cannila, Larry Lubow, Charles Shioleno, and Arthur Geller. Each of these physicians took the time to help me acquire the interpretive skills I have today. I could not have produced this book without help from the staff of the Cardiac Department at Morristown Hospital and the Cardio-Pulmonary Department at Wilcox Memorial Hospital in Kauai, Hawaii, where I now live. They took the time to collect many ECGs and arrhythmia strips for me to choose from to include in my books. xi CONTENTS 1 WHAT IS AN ELECTROCARDIOGRAM? 1 Standard Leads 3 Augmented Leads 5 Precordial Leads 6 2 CARDIAC CELLS 9 Depolarization and Repolarization 10 Electrophysiologic Properties of a Cardiac Cell 11 3 ANATOMY OF THE HEART AND THE ELECTRICAL CONDUCTION SYSTEM 13 Anatomy 14 Electrical Conduction System 17 4 PQRSTU WAVES, COMPLEXES, INTERVALS, AND SEGMENTS 23 Waves and Complexes 24 Intervals and Segments 26 Kinds of QRS Complexes 28 5 ECG GRAPH PAPER AND MEASUREMENTS 31 Time and Voltage 32 Measurements 35 6 DETERMINATION OF HEART RATE AND NORMAL HEART RHYTHMS 37 Determination of Heart Rate 38 Practice ECGs 43 Answers for Practice ECGs 53 7 NORMAL 12-LEAD ECG CONFIGURATIONS 55 Vectors 56 Standard, Augmented, and Precordial Lead Configurations 58 xiii