SOLVD was initiated in 1986 primarily to evaluate the effects of enalapril, an angiotensin-converting enzyme (ACE) inhibitor. Two considerations influenced the design of SOLVD: it was possible that drug treatment given to patients who already had manifest congestive heart failure might not be as beneficial as initiating treatment in asymptomatic left ventricular dysfunction patients; early treatment of such asymptomatic patients might be less beneficial, as the patient might not have measurable activation of the renin-angiotensin axis.