Cardiopulmonary exercise testing before and after conditioning in older coronary patients

Abstract

Cardiac rehabilitation has been demonstrated to improve aerobic capacity in young and middle-aged coronary patients. The effect of an aerobic conditioning program on cardiopulmonary markers of fitness was assessed in 22 older patients (mean age 68 years) following a coronary event compared with 37 younger patients (mean age 52 years). Before conditioning, peak oxygen consumption was lower in the older patients, 16.9 versus 24.3 cm3/kg/min (p less than 0.001), as was exercise duration and maximal ventilation. Older coronary patients were more likely to stop exercise at a respiratory equivalent ratio of less than 1.00 (8 of 22 versus 4 of 37, p less than 0.05) and therefore often did not attain a true maximal cardiopulmonary limitation. Both groups had similar increases in peak oxygen consumption following a 36-session conditioning program, improving 27% in the older group and 23% in the younger group. Duration of treadmill exercise on a Balke treadmill protocol increased similarly in the two groups, 62% in the older group (from 8.9 to 14.3 minutes) and 40% in the younger group (from 12.2 to 17.1 minutes) (p = NS). Thus while older patients following coronary events are substantially less fit than younger patients, they obtain a similar relative improvement of aerobic capacity with a graded conditioning program.