EFFECTS OF LEFT VENTRICULAR DIASTOLIC DYSFUNCTION ON EXERCISE CAPACITY THREE TO SIX WEEKS AFTER ACUTE MYOCARDIAL INFARCTION

Abstract

The mechanisms responsible for limiting exercise capacity in patients with left ventricular dysfunction have not been completely clarified. Several studies have demonstrated that measurements of left ventricular systolic function do not predict exercise capacity in patients with this disorder. Recently, however, investigators have demonstrated that abnormalities of diastolic function of the heart provide important contribution to the signs and symptoms experienced by patients with heart disease. The present study examines the relation between left ventricular diastolic function and maximal exercise capacity in patients with recent myocardial infarction. The study included 30 patients who had had acute myocardial infarction three to six weeks before the study. All patients were subjected to history taking, clinical evaluation, chest radiography, Doppler echocardiography, and upright treadmil exercise testing. Left ventricular diastolic function was evaluated using the following Doppler derived indices : 1. Peak filling rate normalized to stroke volume. 2. lsovolumic relaxation time.