Cardiac Adaptation To Hemodynamic Overload Training And Stress

Cardiac hypertrophy and accompanying phenomena have received increasing attention in recent years - particularly in the basic sciences. The present volume contains the proceedings of the Erwin RIESCH SYMPOSIUM on "CARDIAC ADAPTATION TO HEMODYNAMIC OVERLOAD, TRAINING AND STRESS" held in Tiibingen on Sep tember 19-22, 1982. In addition to the topics of the previous symposia (1976 and 1979) concerned with problems of cardiac hypertrophy, the scope of this sequel meeting has been expanded to include related fields. The intention was to consider numerous related features and problems of chronic reactions of the heart (and vascular system) to abnormal hemodynamic loading, as well as alterations due to maturation, aging, training, neuroendocrine status and stress. Special attention has been paid to cardiac reactions at the level of contractile proteins. The results are considered primarily in light of long-term adaptation of the heart. Of course, research at the forefront of current knowledge need not always lead to congruent conclusions. Neither can the individual contributions always agree with the viewpoint of the editors. However, the broad array of individual approaches employed by biochemists, biolo gists, pathologists, physiologists, pharmacologists and clinical cardio logists will certainly help to provide a more balanced interpretation of the results in individual fields, stimulate reexamination of established con cepts and provide direction for future research.

A recent comprehensive study of stress and human health by the Institute of Medicine/National Academy of Sciences concludes that individuals who experience any of a wide range of stressful events or situations are at increased risk of developing a physical or mental disorder, including heart disease. Since cardiovascular disease continues to be a leading cause of illness and death, and since the etiology and pathogenesis of several of the commonest forms of heart disease are incompletely known, it is of fundamental impor tance to study the potential role of stress in the genesis of heart disease. Accordingly an International Symposium on Stress and Heart Disease was held in Winnipeg, Canada, June 26-29, 1984 and the proceedings form the basis of this book and its companion volume, "Stress and Heart Disease". The connection between stress (the behavioral sciences) and heart disease (the biomedical sciences) occurs in the mechanisms through which the brain affects or controls the endocrine and the autonomic nervous systems. Initially this linkage appeared to be relatively simple, mainly involving catecholamines and corticosteroids, and communication between nerve cells was thought to be electrical. Now knowledge has increased and concepts have change dramatic ally. Major advances have occurred in biochemical, anatomical, physiological, pharmacological, pathological and behavioral aspects of the neuroendocrine system. The over whelming significance of chemical communication in the nli xviii nervous system has become clear.

Heart disease, despite recent improvements, continues to be the single most im portant cause of death and disability in the United States. It is estimated that the direct cost of medical care for cardiovascular disease is $6 billion dollars per year. Data compiled by the National Center for Health Statistics reveal a dramatic de cline in deaths from cardiovascular disease in the United States (greater than 20% since 1968). This phenomenon has been the subject of in-depth study. It is clear that the decline is real and not a statistical artifact. The decrease in mortality has been noted in all sections of the country, though the onset and rate of decline varies in different regions of the country. Both primary prevention, through changes in risk factors, and basic and applied research leading to earlier recognition and im proved treatment have contributed to the decline. They do not fully explain the decline. Further research is needed to clarify this issue. Clinical cardiologists have been exposed to a veritable explosion of new knowl edge of mechanisms of cardiovascular disease, development of new improved non-invasive diagnostic techniques, and the pharmacodynamics of agents affect ing the cardiovascular system. This new knowledge results from contributions made by individuals from diverse disciplines including cellular and molecular bi ologists, geneticists, hematologists, cardiologists, and cardiovascular surgeons.

Heart failure continues to be a major public health problem in the United States with close to half a million new cases diagnosed each year. Moreover, deaths from heart failure are on the increase, in part because of advances in the treatment of other fatal diseases, and in part from the prevalence of lifestyles indifferent to the risk factors for heart disease. This is not to say that no progress has been made in the treatment of heart failure. While for many years treatment was confined to the management of the symptoms, in recent years with the advent of ACE inhibitor and ß blacker therapies, real improvements in cardiac function and life expectancy have been achieved (Volume 4B, Leier). On a more basic level, enormous advances have been made in describing many of the changes in structure and function of the heart and the parallel neurohumoral and circulatory adaptations that occur during the onset of failure. These advances have been made not only by using various animal models of heart failure, but also using fresh failing human heart tissue, which has become readily available for experimental investigation since the advent of cardiac transplantation. Understanding the significance of many of these changes that occur during the transition to failure and the role they play in the etiology of failure is, however, a much more difficult task. These are exciting times in heart failure research. It is as though many of the pieces of the jigsaw puzzle are available but the puzzle has yet to be assembled. The objective of these volumes is to bring together some advances that have been made in recent years in defining one aspect of the failing heart, that is, the role of altered metabolism, in order to facilitate assembly of the puzzle.

Research at the molecular and the cellular level has greatly enhanced our understanding of the pathogenesis and management of heart disease. Valuable contributions, towards this end, have been made by scientists from different dis ciplines including biochemistry, physiology, pathology, molecular biology and biophysics. We felt that it would be of interest and value to bring together ex perts from diverse specialities to present their work and to discuss the common problems encountered in their endeavours. In accordance, a symposium was organised in February 1988 at the Postgraduate Institute of Medical Education & Research, Chandigarh. It was held during the annual meeting of the Indian section of the International Society for Heart Research. This book is a compila tion of some of the papers presented at the symposium. The symposium was sponsored by the Council on Cardiac Metabolism of the International Society and Federation of Cardiology. A number of Indian or ganisations gave generous financial help. These included the National Academy of Medical Sciences, Indian Council of Medical Research, Council of Scientific and Industrial Research and Department of Science and Technology. Desktop publishing was used to prepare this volume. In doing so we came to appreciate the remarkable qualities, skills and help rendered by Professor Dharam Vir. For typing the manuscripts and for other secretarial assistance we gratefully acknowledge the help of Ravinder and Sawtantar. PATHOPHYSIOLOGY AND PHARMACOLOGY OF HEART DISEASE 1 THE NEWBORN PIG HEART, A SUPERIOR ANIMAL MODEL OF CARDIAC HYPERTROPHY Howard E.

The latest developments in molecular biology have broadened our understanding of the pathogenesis of idiopathic dilated cardiomyopathy (IDC). In this book, written by well-known experts, a comprehensive overviewof IDC is given, including basic cellular and molecular concepts, virology, immunology, cardiac receptors and ionic channels, contractility abnormalities, microcirculation, and oxygen supply in cardiac hypertrophy. Details on basic research are supplemented by results of new clinical trials in IDC and the latest data on the epidemiology of the disease. For those who are interested in the disease, the book summarizes progress in all major fields.