EFFECTS OF NISOLDIPINE AND OR ENALAPRIL ON LEFT-VENTRICULAR FUNCTION AND EXERCISE CAPACITY IN PATIENTS WITH RECENT ANTERIOR MYOCARDIAL-INFARCTION AND MILD CARDIAC DYSFUNCTION/

Treatment of abnormal remodeling and dysfunction of left ventricle aft er myocardial infarction is one of the major goals of recent therapeut ic interventions. The current study, the Nisoldipine Enalapril Anterio r Myocardial Infarction Study pilot investigation, was designed to inv estigate the effects of 12 weeks of treatment with enalapril or nisold ipine or their combination on left ventricular (LV) function and exerc ise capacity in patients with recent (<1 month) anterior myocardial in farction and mild LV dysfunction (LV ejection fraction [EF] 38% to 48% ). Forty-six patients were studied and received, by random assignment, enalapril (5 mg once per day) plus placebo (n = 14) or nisoldipine (1 0 mg two times per day) plus placebo (n = 18) or enalapril (5 mg once per day) plus nisoldipine (10 mg two times per day) (n = 14). All pati ents received aspirin (325 mg) throughout the study. Data on iv EF and peak filling rate at rest and LV EF during exercise were collected du ring radionuclide ventriculography. In addition, the product of heart rate and systolic blood pressure (rate-pressure product) and exercise time were determined during exercise stress testing. The analyzed para meters were not significantly modified after treatment with enalapril or with nisoldipine. In contrast, the combination of enalapril and nis oldipine significantly raised LV EF at rest (from 43% +/- 3% to 48% +/ - 6%, p < 0.01) and during exercise (from 45% +/- 8% to 50% +/- 9%, p < 0.01) and raised peak filling rate at rest (fraction of end-diastoli c volume per second) from 1.57 +/- 0.3 to 1.67 +/- 0.3 (p < 0.05). In addition, the combined administration of the two drugs increased the r ate-pressure product (values x 10(3)) (from 20.7 +/- 5 to 22.7 +/- 4, p < 0.05) and increased exercise time (from 573 +/- 173 seconds to 668 +/- 178 seconds, p < 0.05). These results show that in patients with recent anterior myocardial infarction and mild LV dysfunction, the com bination of the angiotensin-converting enzyme inhibitor enalapril and the dihydropyridine nisoldipine improves resting LV systolic and diast olic function and exercise LV systolic function and exercise capacity.