Results of the veterinary enalapril trial to prove reduction in onset of heart failure in dogs chronically treated with enalapril alone for compensated, naturally occurring mitral valve insufficiency.

Objective: To determine the efficacy of long-term enalapril administration in delaying the onset of congestive heart failure (CHF).

Design: Placebo-controlled, double-blind, multicenter, randomized trial.

Animals: 124 dogs with compensated mitral valve regurgitation (MR).