Relationship Between Left Ventricular Diastolic Function at Rest and Exercise Capacity in Patients who Have Suffered a Previous Myocardial Infarction

Abstract

To assess whether left ventricular (LV) diastolic function is a determinant of exercise capacity in patients who have suffered a previous myocardial infarction (MI), we investigated the relationship between maximum exercise duration and resting LV diastolic function in 65 MI patients. Each patient underwent both a symptom-limited exercise test and LV biplane angiography with simultaneous high-fidelity pressure measurements. LV relaxation was assessed by the time constants (T1/e and T1/2) 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 exercise capacity (r=-0.19 for T1/e, NS; r=-0.17 for T1/2, NS). LV diastolic distensibility also did not correlate with exercise capacity (r=-0.08, NS). These results suggest that the resting LV diastolic dysfunction is unlikely to be the principal cause of exercise intolerance in MI patients without congestive heart failure. © 1997, The Japanese Circulation Society. All rights reserved.