Effect of intravenous nifedipine on hemodynamics and left ventricular function in acute myocardial infarction.

Twenty-one patients with acute myocardial infarction were treated 7.6 +/- 4.9 h after the onset of symptoms with intravenous nifedipine for 48-72 h. No other vasoactive medication was given. Three patients with hypertension did not respond to nifedipine and were excluded from the analysis. In the remaining 18 patients, arterial blood pressure decreased significantly, whereas the heart rate remained unchanged. The mean pulmonary artery and capillary pressure showed a slight but significant decrease. Cardiac index increased significantly. In nine patients, two-dimensional and M-mode echocardiography could be analyzed. The left ventricular ejection fraction increased significantly from 50 +/- 3% to 56 +/- 1%. There was a significant decrease in systemic peripheral resistance index, systolic wall stress, and the calculated myocardial oxygen consumption. These hemodynamic effects persisted throughout the study period. The therapy was well controllable, and there were no significant side effects. Nifedipine improves left ventricular function without an increase in myocardial oxygen demand. This effect is primarily due to afterload reduction.