EXERCISE AND HEART FAILURE
Gary J Balady, Ileana L Piña, eds.
Armonk, New York: Futura Publishing
Company; 1997, 354 pp. ISBN 0-87993-6673
As noted by the editors in the preface to this book, the relationship between heart failure and exercise is an interesting one, in part because of some apparent contradictions. Heart failure, or the inability of the heart muscle to pump blood efficiently, leads to reduced exercise tolerance, which in turn interferes with normal daily activity. On the other hand, objective measurement of an individual's capacity for exercise is an integral part of the management of patients with chronic heart failure, since it provides prognostic information that is useful in deciding on a particular medical or surgical procedure, as in the case of patients awaiting a transplant.
For several years now exercise has been viewed as a therapeutic intervention in and of itself, its effectiveness having been established for the treatment of patients with stable heart failure and for the rehabilitation of heart transplant recipients. Because its use is new, there is still much to be learned about the benefits of different types of exercise and their frequency and intensity, which are precisely the issues addressed in this book.
The book opens with a discussion of the enormous social and economic burden represented by patients with chronic heart failure and of the increasing numbers of deaths caused by the disease. Such an increase, which might appear to be the result of the aging of the population, persists even after the data are adjusted for age. One contributing factor may be the longer survival of patients with cardiovascular diseases, such as coronary artery disease and hypertension, and their eventual progression to symptomatic chronic heart failure.
Usually, the only therapeutic approach in patients with left ventricular failure and heart transplant recipients is treatment with a combination of drugs. However, drugs should be accompanied by proper physical activity and a diet low in sodium. Among the benefits of regular aerobic exercise for patients with stabilized heart failure, the book cites the resolution of myocardial hypertrophy and protection against hypoxic and ischemic damage. There is less information available on the benefits of exercise in patients who have received a heart transplant, whose rehabilitation should be approached more cautiously.
The book also describes in detail the methods used for evaluating tolerance to exercise, which can be ergonometric (treadmill or bicycle) or simple measurements of arterial blood gases or of oxygen and carbon dioxide in exhaled air. In addition, it explains their usefulness in determining the degree of failure and deciding on the proper treatment. Detailed information is provided on how to use exercise therapeutically, with an emphasis on the importance of examining the patient, taking note of his medications and health problems (obesity, diabetes, chronic obstructive pulmonary disease, peripheral vascular disease, etc.), obtaining laboratory data, and performing exercise tolerance tests. The chapters dealing with physical exercise programs provide practical explanations that make it possible to apply the techniques under adequate supervision. The concluson is that cardiac rehabilitation services are currently underused but that they are vitally important, since cost-benefit studies have shown their effectiveness in reducing the number and length of hospitalizations and in enabling patients to perform their daily activities without dyspnea or excessive fatigue.
This book can be obtained directly from: Futura Publishing Co., Inc., PO. Box 330, 295 Main Street, Mt. Kisco, New York 10549, USA.