LEFT-VENTRICULAR FUNCTION IN CHRONIC AORTIC REGURGITATION

[摘要] Left ventricular performance was determined in 42 patients with moderate or severe aortic regurgitation during upright exercise by measuring left ventricular ejection fraction and volume with radionuclide ventriculography. Classification of the patients according to exercise tolerance showed that patients with normal exercise tolerance (.gtoreq. 7.0 min) had a significantly higher ejection fraction at rest (P = 0.02) and during exercise (P = 0.0002), higher cardiac index at exercise (P = 0.0008) and lower exercise end-systolic volume (P = 0.01) than did patients with limited exercise tolerance. Similar significant differences were noted in younger patients compared with older patients in ejection fraction at rest and exercise (both P = 0.001) and cardiac index at rest (P = 0.03) and exercise (P = 0.0005). The end-diastolic volume decreased during exercise in 60% of the patients. The patients with a decrease in volume were significantly younger and had better exercise tolerance and a larger end-diastolic volume at rest than did patients who showed an increase in volume. The mean corrected left ventricular end-diastolic radius/wall thickness ratio was significantly greater in patients with abnormal than in those with normal exercise reserve (mean .+-. SD 476 .+-. 146 vs. 377 .+-. 92 mm Hg, P < 0.05). Thus, in patients with chronic aortic regurgitation: left ventricular systolic function during exercise was related to age, exercise tolerance and corrected left ventricular end-diastolic radius/wall thickness ratio, and the end-diastolic volume decreased during exercise, especially in younger patients and patients with normal exercise tolerance or a large volume at rest.