The clinical results of the Studies of Left Ventricular Dysfunction (SOLVD) Treatment Trial have been published previously, but no evaluation of cost-effectiveness based on the primary data has been reported. The authors used a decision analytic model based on primary data from SOLVD to estimate years of survival (overall, by New York Heart Association Class, and quality-adjusted) and to estimate costs of nonfatal hospitalizations, ambulatory care, therapy with enalapril, and deaths. Clinical and resource utilization data were derived from participants in SOLVD, and cost data were derived from the United States. Therapy with enalapril during the approximate 48-month follow-up period in SOLVD resulted in a gain of 0.16 year of life and savings of dollars 718. During the patient's lifetime, a survival benefit of 0.40 year, a cost per year of life saved of dollars 80, and a cost per quality-adjusted life year of dollars 115 with the use of enalapril were projected. The results indicated a net savings and gain in life expectancy during the SOLVD treatment trial. The lifetime projection suggests that therapy with angiotensin-converting enzyme inhibitors, such as enalapril, is extremely attractive when compared with many commonly used interventions in patients with cardiovascular disease or heart failure.