- Question
- To assess whether adding enalapril to conventional therapy improves survival in patients with severe congestive heart failure (NYHA functional class IV).
- Design
- Randomized, double-blind, placebo-controlled study of 253 patients (127 assigned to enalapril and 126 to placebo). Follow-up averaged 188 days (range, 1 day to 20 months).
- Population
- Patients with severe congestive heart failure in NYHA functional class IV who continued conventional treatment, including other vasodilators.
- Intervention
- Enalapril 2.5 to 40 mg per day added to conventional therapy. In high-risk patients the initial dose was reduced to 2.5 mg daily.
- Control
- Placebo on top of conventional heart failure treatment.
- Primary outcome
- Crude all-cause mortality at six months.
- Results
- Six-month mortality was 26% with enalapril versus 44% with placebo, a 40% reduction (P = 0.002). By the end of the study there were 50 deaths in the enalapril group and 68 in the placebo group, a 27% reduction (P = 0.003).
- Safety
- Overall withdrawal rates were similar between groups, but hypotension requiring withdrawal occurred in seven patients on enalapril and none on placebo. This effect was less frequent after the initial dose was lowered in high-risk patients.
- Conclusion
- Adding enalapril to conventional therapy in severe heart failure reduces mortality and improves symptoms, driven by fewer deaths from progressive heart failure.
- Why it matters
- It was one of the first demonstrations that an angiotensin-converting-enzyme inhibitor prolongs life in advanced heart failure, laying the groundwork for the use of this drug class in the treatment of the disease.
Card generated automatically with AI from the abstract of the original publication and the trial registry; every figure was checked against those sources. It may contain errors: verify the data at the source before using it for clinical decisions.
Generated on October 7, 2026