[Comparison of captopril with enalapril in the therapy of heart failure: effect on hemodynamics and kidney function].

24 patients with severe heart failure (NYHA III) were randomly assigned to an additional therapy with captopril or enalapril. The mean daily dose of captopril was 56 +/- 2 mg and of enalapril, 9.6 +/- 0.9 mg. After a mean of 9 days, the influence of both inhibitors of the angiotensin converting enzyme (ACE-inhibitors) on hemodynamics and renal function was evaluated. The mean arterial pressure in the group treated with captopril (group A) fell by 11 +/- 2 mm Hg (p less than 0.001), with enalapril (group B) by 13 +/- 3 mm Hg (p less than 0.01), the difference between the groups not being significant. Heart rate decreased in both groups to a similar degree. The change was significant only in the patients treated with enalapril (13 +/- 4/min; p less than 0.05 vs. 11 +/- 5/min in group A). Stroke volume index increased by 10 +/- 2 ml/m2 in group A vs. 12 +/- 2 ml/m2 in group B; both increases were highly significant (p less than 0.001). Mean decreases in pulmonary artery and right atrial pressure were comparable in both groups. The hemodynamic improvement was not different with both ACE-inhibitors. Serum sodium and potassium before therapy were 137 +/- 1 mmol/l and 4.1 +/- 0.2 mmol/l in group A and 139 +/- 1 mmol/l and 3.8 +/- 0.1 mmol/l in group B and serum creatinine was 1.2 +/- 0.1 mg/dl in both groups. Neither serum electrolytes nor serum creatinin were changed significantly by therapy with captopril or enalapril.(ABSTRACT TRUNCATED AT 250 WORDS)