Effects of enalapril on long-term mortality in severe congestive heart failure. CONSENSUS Trial Group

All surviving patients in a double-blind study comparing the effects of enalapril and placebo on survival in severe congestive heart failure were recommended to be treated with active drug after stopping the trial. Two-year follow-up from the end of the blinded trial demonstrated that among 77 survivors of 127 patients originally allocated to the group with enalapril, 38 were still alive. Of 126 patients allocated to the group with placebo 58 survived the blinded study, and after 2-year follow-up 26 were still alive. Thus, the difference between the original treatment groups remained, despite that treatment with enalapril was made available to all surviving patients and that those in the group with enalapril were sicker at baseline than those in the group with placebo. If enalapril was prescribed, the mortality was 47% compared with 75% if it was not. Life-table analysis suggests a marked carry-over effect of treatment in the group with enalapril that lasted for up to 15 months before mortality rates became comparable in the 2 treatment groups. This strongly suggests that enalapril confers structural protection to the failing myocardium.