RELATIONSHIP BETWEEN LEFT-VENTRICULAR DIASTOLIC FUNCTION AT REST AND EXERCISE CAPACITY IN PATIENTS WHO HAVE SUFFERED A PREVIOUS MYOCARDIAL-INFARCTION

To assess whether left ventricular (LV) diastolic function is a determ inant of exercise capacity in patients who have suffered a previous my ocardial infarction (MI), we investigated the relationship between max imum exercise duration and resting LV diastolic function in 65 MI pati ents. Each patient underwent both a symptom-limited exercise test and LV biplane angiography with simultaneous high-fidelity pressure measur ements. LV relaxation was assessed by the time constants (T-1/e and T- 1/2) of isovolumic pressure decay, and LV diastolic distensibility was assessed by the LV end-diastolic volume (V) index-pressure (P) ratio. The time constants of relaxation did not correlate with maximum exerc ise capacity (r=-0.19 for T-1/e, NS; r=-0.17 for T-1/2, NS). LV diasto lic distensibility also did not correlate with exercise capacity (r=-0 .08, NS). These results suggest that the resting LV diastolic dysfunct ion is unlikely to be the principal cause of exercise intolerance in M I patients without congestive heart failure.