Cardiac evaluation of a physical rehabilitation program for patients with ischemic heart disease.

A reconditioning exercise program that was applied to group of 12 coronary patients resulted in an increase of their tolerance to physical work and of their maximal working capacity. In some instances the improvement in physical condition was accompanied by changes in indicators of cardiac function which suggest that an improvement in myocardial performance also occurred. Although some evidence of this has been presented, more studies are needed for substantiation. It is believed, on the other hand, that to explain the improvement of the patient, it is not necessary to invoke an improvement of myocardial performance. An improvement of patient's tolerance to physical work may also be explained by extracardiac mechanisms that produce changes in arterial peripheral resistance, regional blood flow distribution, overall mechanical efficiency, muscle capillarization, fiber size and mitochondrial enzymatic activity, patterns of sweating, adaptation between pulmonary ventilation and circulation, work of breathing efficiency, autonomic nervous system balance and in the adaptive responses of the neuroendocrine system which mediate between psychic and physiological behavior. All of these changes have been observed in healthy individuals submitted to physical training. It is plausible to assume that they may also occur in the patient with ischemic heart disease. What is to be shown is which one or which ones of these mechanisms prevail in a given individual.