The parameters of vascular responsiveness to vasopressors and vasodilators and the clinical severity index were determined in 45 patients with various acute myocardial infarction (AMI) extents in the hospital period. In a group of patients with small AMI foci, the responsiveness to vasopressors normalized on day 14 with normal parameters to vasodilators throughout the study. The mean clinical severe index was the highest. In a group of patients with gross and transmural AMI there was a high responsiveness to norepinephrine in the whole hospital period and a high clinical severity index. Patients with fatal AMI outcomes showed an extremely low responsiveness to norepinephrine in the whole hospital period and a low abnormal response to histamine. The clinical severity index corresponded to the most grave course leading to an unpredictable outcome without any trends to decrease.