Comparison of the Acute Hemodynamic Response to Intravenous Nisoldipine (Bay K 5552) and Intravenous Nifedipine for Left Ventricular Dysfunction Secondary to Myocardial Infarction

Dihydropyridine calcium blocking drugs exert potentially dangerous negative inotropic action in selected patients with severe left ventricular dysfunction. In 10 patients peripheral and central hemodynamic effects of nisoldipine were intraindividually compared with nifedipine using a sequential crossover protocol. The drugs were titrated to a similar steady-state reduction of mean arterial pressure by 15 +/- 3% and 15 +/- 2% and systemic vascular resistance by 25 +/- 5% and 17 +/- 2%, respectively. The equi-effective dosage was 0.17 +/- 0.06 microgram/min/kg for nisoldipine and 0.58 +/- 0.1 microgram/min/kg for nifedipine. In contrast to nifedipine, administration of nisoldipine was associated with increases in cardiac index of 0.45 +/- 0.33 liters/min/m2 (p less than 0.05), stroke volume index of 3.91 +/- 3.0 ml/m2 (p less than 0.05) and left ventricular ejection fraction of 4.6 +/- 2.8% (p less than 0.05). Mean pulmonary capillary wedge pressure decreased with nisoldipine from 11.8 +/- 3.4 to 8.0 +/- 3.4 mm Hg (p less than 0.005) and mean pulmonary arterial pressure from 20.4 +/- 4.06 to 16.1 +/- 3.2 mm Hg (p less than 0.005); these variables were unaffected by nifedipine. Thus, intraindividual comparison revealed no cardiodepressive action of nisoldipine, whereas with nifedipine the conceptually beneficial effect of afterload reduction appears to be offset by intrinsic negative inotropic action. Due to higher vasospecificity and more effective unloading, nisoldipine appears to be superior to nifedipine in patients with left ventricular dysfunction secondary to ischemic heart disease.