Acute effects of intravenous nisoldipine on left ventricular function after acute myocardial infarction.

Nisoldipine is a calcium antagonist with potent coronary vasodilating effects in patients with chronic stable angina pectoris. In an initial study we showed that intravenous nisoldipine, given 24-72 hours after uncomplicated myocardial infarction, was a safe and feasible intervention that had beneficial effects on global and regional myocardial function. We subsequently studied the acute effects of nisoldipine in six patients within 24 hours (mean 14 +/- 4 hours) after the onset of myocardial infarction. Nisoldipine was administered as a 4.5 micrograms/kg intravenous bolus over 3 minutes, followed by intravenous infusion of 0.2 microgram/kg over 60 minutes. Radionuclide angiography, cardiac output, and intraarterial 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 (p = 0.0001). Heart rate increased from 78 +/- 12 to 88 +/- 11 min-1 (p = 0.004). Mean arterial blood pressure decreased from 92 +/- 20 to 79 +/- 13 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 hours.