To evaluate the left ventricular systolic performance and the peripheral vascular response during exercise (Ex) in patients (pts) with myocardial infarction (MI), we performed a bicycle ergometer Ex in the supine position on 5 normal subjects (Group C) and 21 pts with MI. Pts were divided into three groups, based on the number of major coronary arteries with greater than 75 per cent stenosis : Group N (5 pts with no significant stenosis)