Effect of physical training on treadmill exercise capacity, collateral circulation and progression of coronary disease

Abstract

The increased exercise capacity after physical training in patients with coronary artery disease has been attributed to improved oxygen supply to the myocardium by way of increased collateral circulation or reduction of myocardial oxygen consumption by extracardiac factors, or both. Fourteen patients aged 43 to 61 years (mean 51 years) with 50 percent or greater obstruction in one, two or three vessels (three, six and five patients, respectively) underwent 13 months of physical training. Clinical status was either stable or improved with training. Treadmill exercise capacity, as measured by oxygen consumption, increased 25 percent from 21.9 ± 4.8 (standard deviation) to 27.4 ± 4.1 ml/kg-min at heart rates of 154 ± 17 and 156 ± 12 beats/min, respectively. After training, new collateral vessels, apparently secondary to progression of the disease, were observed in 2 of 21 arteries significantly but not completely obstructed before training. These data are in contrast to those reported for trained dogs with incomplete obstruction. Coronary arterial lesions progressed in only 4 of 14 patients. Coronary arteriographic data from this laboratory do not support the hypothesis that the increased exercise capacity after training in patients with coronary disease can be attributed to the development of collateral circulation. It is possible that physical training may retard the progression of coronary artery disease.