The acute effects of intravenous nisoldipine on left ventricular function within 24 h after acute myocardial infarction.

Nisoldipine is a calcium antagonist with potent coronary vasodilating effects in patients with chronic stable angina pectoris. We studied the acute effects of nisoldipine in six patients within 24 h (mean 14 +/- 4 h) after the onset of myocardial infarction. Nisoldipine was administered as a 4.5 micrograms kg-1 intravenous bolus over 3 min followed by intravenous infusion of 0.2 microgram kg-1 min-1 during 60 min. Radionuclide angiography, cardiac output and intra-arterial blood pressure measurements were performed before and during nisoldipine. Left ventricular ejection fraction increased from 48.3 +/- 10.3% to 55.3 +/- 11.8% (P = 0.034) during nisoldipine infusion. Regional wall motion score changed during nisoldipine infusion from 3.3 +/- 2.5 to 1.8 +/- 2.6 (P = 0.027). Cardiac output increased from 5.5 +/- 1.0 to 7.3 +/- 1.3 l min-1 (P = 0.0001). Heart rate increased from 78 +/- 12 to 88 +/- 11 beats.min-1 (P = 0.004). Mean arterial blood pressure decreased from 91.7 +/- 20.2 to 78.7 +/- 13.1 mmHg (P = 0.038). The rate-pressure product did not change significantly during nisoldipine infusion. It is concluded that nisoldipine improves global and regional left ventricular function in patients with acute myocardial infarction within the first 24 h. Our findings suggest that this effect is achieved without increasing myocardial oxygen demand.