Losartan (25 or 50 mg/day) and enalapril (20 mg/day) showed no significant differences in exercise capacity, clinical status, or adverse events after 8 weeks in patients with severe heart failure.
RCT (n=166)
Double-blind
randomly assigned
Yes
Does losartan maintain clinical status and exercise performance comparably to enalapril in patients with moderate or severe chronic heart failure?
Losartan and enalapril demonstrate comparable short-term efficacy and tolerability in patients with moderate to severe heart failure.
OBJECTIVES: This study assessed the feasibility of an efficacy trial comparing angiotensin-converting enzyme inhibition and angiotensin II receptor antagonism in heart failure. Patients with moderate or severe heart failure whose condition had previously been stabilized by treatment with a converting enzyme inhibitor were randomly assigned to receive enalapril or losartan. The study was designed to detect any signs of clinical deterioration during double-blind treatment. BACKGROUND: Losartan is a specific, nonpeptide angiotensin II receptor-1 antagonist with a vasodilator hemodynamic profile similar to that of converting enzyme inhibitors. Although therapy with specific receptor blockade has certain theoretic advantages over nonspecific converting enzyme inhibition, demonstration of a comparable therapeutic effect in patients with congestive heart failure will require a major effort comparing two active agents. METHODS: One hundred sixty-six patients with stable heart failure in New York Heart Association functional class III or IV and an ejection fraction < or = 35% were included in a multicenter, double-blind, parallel, enalapril-controlled trial. After a 3-week stabilization period with optimal therapy, including digitalis, diuretic drugs and a converting enzyme inhibitor, patients were randomly assigned to 8 weeks of therapy with losartan, 25 mg/day (n = 52); losartan, 50 mg/day (n = 56); or enalapril, 20 mg/day (n = 58). Patients were assessed with frequent clinical and laboratory evaluation and exercise testing. RESULTS: No significant differences between groups in terms of changes in exercise capacity (6-min walk test), clinical status (dyspnea-fatigue index), neurohumoral activation (norepinephrine, N-terminal atrial natriuretic factor), laboratory evaluation or incidence of adverse experience were observed. CONCLUSIONS: The results suggest that losartan and enalapril are of comparable efficacy and tolerability in the short-term treatment of moderate or severe congestive heart failure. A trial designed to compare the efficacy, tolerability and effect on mortality of long-term angiotensin II receptor blockade with converting enzyme inhibition is both feasible and ethically responsible.
Dickstein et al. (Tue,) conducted a rct in moderate or severe chronic heart failure (n=166). Losartan vs. Enalapril 20 mg/day was evaluated on Changes in exercise capacity, clinical status, neurohumoral activation, laboratory evaluation or incidence of adverse experience. Losartan (25 or 50 mg/day) and enalapril (20 mg/day) showed no significant differences in exercise capacity, clinical status, or adverse events after 8 weeks in patients with severe heart failure.