Abstract

The purpose of this study was to examine the relationship between maximal O2 uptake (VO2max) and left ventricular systolic function in coronary artery disease. We studied 27 patients, age 50 +/- 10 years, asymptomatic and able to attain true VO2max. In patients whose ejection fraction decreased with exercise, VO2max was 21 +/- 4 vs 27 +/- 4 ml/kg/min in those whose ejection fraction increased. Systolic blood pressure/end-systolic volume relation was shifted upward and to the right in the former group in response to peak exercise. In contrast, the pressure volume relation was shifted upward and to the left in patients whose ejection fraction increased with exercise. Ejection fraction at rest did not correlate with VO2max. There was a significant but weak correlation between peak exercise ejection fraction and VO2max. Left ventricular exercise reserve (change in ejection fraction from rest to exercise) correlated with VO2max, maximal O2 pulse, and maximal heart rate during exercise. Maximal heart rate during exercise correlated with VO2max. These data suggest that impaired left ventricular function can limit VO2max and that maximal heart rate and left ventricular exercise reserve are among the variables affecting VO2max in patients with coronary artery disease who are not limited by angina. Verf.-Referat