[Effect of cilazapril on exercise tolerance and neurohumoral factors in patients with asymptomatic chronic heart failure after myocardial infarction].

The effects of cilazapril on exercise tolerance and neurohumoral factors were investigated in old myocardial infarction (OMI) patients with asymptomatic heart failure and reduced left ventricular ejection fraction. Cilazapril (0.5 mg) was administered once daily to OMI patients (n = 20) [NYHA class I, sinus rhythm, ejection fraction by radionuclide scanning < 50% (36.8 +/- 9.1%, mean +/- SD)]. Two weeks later, five patients were excluded from the study because of cough or hypotension, and 15 patients received 1.0 mg cilazapril once daily for the next 6 weeks. Exercise tolerance, neurohumoral factors and ejection fraction were measured in OMI patients before and after administration of cilazapril. Seven age-matched healthy adults served as the controls. OMI patients had latent heart failure because their exercise tolerance values and aldosterone levels were lower and alpha-atrial natriuretic polypeptide levels were higher than those in healthy subjects. In OMI patients, 8 weeks after cilazapril administration, exercise duration increased from 545 +/- 59 to 590 +/- 74 sec (p < 0.05), anaerobic threshold from 17.5 +/- 3.2 to 20.1 +/- 2.8 ml/min/kg (p < 0.05), peak-VO2 from 23.5 +/- 4.7 to 27.1 +/- 4.4 ml/min/kg (p < 0.05), plasma renin activity from 1.34 +/- 1.13 to 5.82 +/- 5.47 ng/ml/hr (p < 0.01) and alpha-atrial natriuretic polypeptide decreased from 100.7 +/- 44.3 to 80.5 +/- 28.0 pg/ml (p < 0.05). In patients with asymptomatic left ventricular dysfunction after myocardial infarction, 8 week's cilazapril administration improved exercise tolerance and neurohumoral conditions.