INTRAVENTRICULAR CONDUCTION DISTURBANCES

Transcription

1 INTRAVENTRICULAR CONDUCTION DISTURBANCES

2 DEVELOPMENTS IN CARDIOVASCULAR MEDICINE VOLUME 12 Other volumes in this series: 1. Lancee CT, ed: Echocardiology ISBN Baan 1, Arntzenius AC, Yellin EL, eds: Cardiac dynamics ISBN Thalen HlT, Meere CC, eds: Fundamentals of cardiac pacing ISBN Kulbertus HE, Wellens HJJ, eds: Sudden death ISBN X. 5. Dreifus LS, Brest AN, eds: Clinical applications of cardiovascular drugs ISBN Spencer MP, Reid 1M, eds: Cerebrovascular evaluation with Doppler ultrasound ISBN Zipes DP, Bailey 1C, Elharrar V, eds: The slow inward current and cardiac arrhythmias ISBN Kesteloot H, 100ssens 1V, eds: Epidemiology of arterial blood pressure ISBN Wackers FlT, ed: Thallium-20l and technetium-99m-pyrophosphate myocardial imaging in the coronary care unit ISBN Maseri A, Marchesi C, Chierchia S, Trivella MG, eds: Coronary care units ISBN Morganroth 1, Moore EN, Dreifus LS, Michelson EL, eds: The evaluation of new antiarrhythmic drugs. ISBN series ISBN

3 INTRA VENTRICULAR CONDUCTION DISTURBANCES by PAOLOALBONI, M.D. Director, Electrophysiology Section Division of Cardiology Arcispedale S. Anna Ferrara, Italy 1981 MARTINUS NIJHOFF PUBLISHERS THE HAGUE / BOSTON I LONDON

4 Distributors: for the United States and Canada Kluwer Boston, Inc. 190 Old Derby Street Hingham, MA USA for all other countries Kluwer Academic Publishers Group Distribution Center P.O. Box AH Dordrecht The Netherlands Library of Congress Cataloging in Publication Data Alboni, Paolo. Intraventricular conduction disturbances. (Developments in cardiovascular medicine; v. 12) Includes index. 1. Heart block. 2. Heart conduction system - Diseases. I. Title. II. Series. [DNLM: 1. Heart ventricle - Physiology. 2. Heart ventricle - Physiopathology. 3. Heart block. WI DE997VME v. 12/ WG 330 A339iJ RC685.B55A ' AACR2 ISBN -13 : e-isbn -13 : DOl: / Copyright 1981 by Martinus NijhofJ Publishers, The Hague. Softcover reprint of the hardcover 1st edition 1981 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher, Martinus NijhofJ Publishers, P.O. Box 566, 25OJ.CN The Hague, The Netherlands.

5 Dedicated to my mother Luisa and my father Giovanni

6 CONTENTS Foreword (by A. Masoni) Preface (by O.S. Narula) Acknowledgements. IX Xl xiii 1. Anatomy of intraventricular conduction system 2. Physiology of ventricular excitation 6 3. Bundle branch blocks Fascicular blocks Bifascicular and trifascicular blocks Peripheral blocks Intraventricular conduction disturbances in congenital heart disease and following cardiac surgery Intraventricular conduction disturbances in acute myocardial infarction. Clinical significance Intraventricular conduction disturbances coexisting with healed myocardial infarction. Diagnostic problems Intermittent intraventricular blocks Prognostic value of HV interval in patients with intraventricular conduction disturbances Noninvasive recording of His-Purkinje activity Effect of anthiarrhythmic drugs on intraventricular conduction Pacemaker therapy in patients with intraventricular disturbances 381 Subject index. 395

7 FOREWORD Rhythm was the first expression of cardiac activity which fell under man's observation, and the heart beat has always represented the very essence of life itself as it accelerates or slows during moments of rest, effort, joy and pain until it comes to a halt at the moment of death. Undoubtedly the heart beat was, for a considerable time, the only semiological element by which man could interpret the dysfunctions of the organism. Even after thousands of years, research into the alterations of cardiac rhythm still holds a certain fascination, although modern methods and sophisticated devices have changed the approach to such studies. Only about ten years ago, the interpretation of arrhythmias was obtained by a standard electrocardiogram to which experimental findings on animals were still arbitrarily applied. On the other hand, the achievement of diagnostic decisions was of little importance outside the sphere of pure intellectual speculation since valid therapeutical treatments were lacking. At present, by means of electrophysiological investigations, one can verify and check 'in situ' the different forms and mechanisms through which rhythm and conduction disorders are manifested. Thus, achieving such a methodology which may be defined as a 'functional biopsy', we are allowed to put forward more accurate therapeutic indications now available using both pharmacological and electrical treatment. That which until a few years ago was left to the art of reasoning, helped by the cardiologist's intuition and imagination, is now thoroughly analysed, measured and compared. Naturally, the extent of the unknown is still perturbing, but it is gradually being narrowed down. As always happens, such increasing improvements as regards equipment and instruments require scientific application and specialistic knowledge stretched to their limits since this extension of the possibilities for research work obviously involves higher risks as far as errors are concerned. This is the reason why so few researchers devote themselves to the study of the formation and conduction disturbances of the impulse. There is a hard point in everyone's life: the circumstances when one chooses one's own way, by which I mean all the wishes, perspectives, expectations and opportunities that push in one or another direction. It is a hard task to determine these choices in young people because some suggestions may interfere heavily with one's

8 x life course, so one may direct somebody to a gratifying as well as to disappointing activity. It is the policy in our Division of Cardiology to allow new assistants to attend to the work that they like best; they are actually free to enter every laboratory: hemodynamics, electrophysiology, ergometry, echocardiography, pacemakers, coronaro-ventriculography, coronary unit, and so on. Before long everyone chooses the most pleasant and interesting for him or herself. At this pont the head of the department must give his suggestions and encouragements. This happened with Dr. Alboni when he began to be attracted by electrophysiological research. I helped and stimulated him regarding his purpose and sent him for some time to Dr. Narula to learn the most refined techniques in this field. At the same time I directed his interest to peripheral conduction disturbances. So this was the origin of this book; a unique one in the sense in which an exhaustive review of the literature is completed with new personal ideas. Dr. Paolo Alboni is 'en route' now; all the best wishes for his journey. Antonio Masoni Head of Division of Cardiology St. Anna Hospital, Ferrara

9 PREFACE It gives me great pleasure to write this preface to Dr. Alboni's monograph on intraventricular conduction disturbances. Having read his manuscript, it is difficult for me to describe adequately in a few paragraphs the value of his contribution or the true excellence of the work. The book represents a complete and completely understandable picture of a complex clinical problem through a lucid synthesis of anatomic, electrocardiographic, vectorcardiographic, electrophysiological and clinical observations. For the first time all of these aspects of intraventricular conduction have been correlated to provide a comprehensive understanding of the subject. It will equip the physician and the cardiologist with an understanding of the fundamentals of intraventricular conduction defects and their variable clinical significance. The material dealing with the diagnosis, clinical course and treatment is complete and convincing. The electrocardiographic illustrations are carefully selected and suitably supplemented with intracardiac electrographic recordings to demonstrate clearly the conduction disturbance under consideration. The style is crisp and clear. The book can be read as well as studied. The presentation of basic information on anatomy, with emphasis on the complexities of the left bundle branch distribution, and physiology of ventricular excitation are carefully discussed in the first two chapters. An elaborate dissertation of bundle branch blocks as well as peripheral blocks is provided in Chapters 3 to 6. The discussion of peripheral blocks resulting from conduction disturbances distal to the bundle branches and the fascicles is mostly based on the author's personal work. This is an important contribution as little has been discussed on this subject in the English literature. Chapters 7 to 9 deal with the pathophysiology, ECG, diagnosis and clinical significance of intraventricular conduction disturbances in association with congenital heart defects, cardiac surgery and myocardial infarction. Intermittent intraventricular blocks are presented in Chapter lo. During the past decade electrophysiologic studies have engendered a great deal of interest. Their role in the clinical management of patients, especially the prognostic value of the H-V interval, is reviewed in Chapter 11. The present status and the limitations of non-invasive recordings of the His-Purkinje system is addressed in Chapter 12. The effect of various antiarrhythmic drugs on intraventricular conduction is reported in Chapter

10 XII 13. The closing chapter deals with therapy of acute and chronic intraventricular conduction defects. This book clearly is and will remain the definitive description of intraventricular conduction disturbances. This book should be of interest to the internist, cardiologist, cardiac surgeon, electrocardiographer, electrophysiologist, medical student, resident and intensive care nurse. Onkar S. Narula Clinical Professor of Medicine University of Miami, Florida

11 ACKNOWLEDGMENTS I should like to give thanks to the many people who have assisted in the preparation of this book. I wish to give special thanks to the following: Prof. Antonio Masoni, who inspired me to write this manuscript and whose guidance and advice have been indispensable; Prof. Onkar Narula, who allowed me to work in his Division of Cardiology, where I could take advantage of his precious teaching on the electrophysiology of the heart; Prof. Lino Rossi, Prof. Bruno Taccardi, Prof. Narasimhan Shantha, Prof. Maria Serratto, Prof. Luigi Tavazzi and Prof. Edoardo Arslan, who kindly reviewed Chapters 1,2,3,7,10 and 12, respectively; Dr. Carlo Malacarne, Dr. Paolo Pedroni, Dr. Laura Filippi, Dr. Roberto Battaglia and Dr. Elisabeth Jenkins for their help in the compilation of the manuscript; Miss Anna Previati and Miss Lucia Malaguti for their excellent secretarial assistance. Finally, I thank my wife Marina for her encouragement and moral support.