The Studies of Left Ventricular Dysfunction (SOLVD)

Objectives:

This study was initiated in 1986 primarily to evaluate the effects of enalapril, an ACE inhibitor, on long-term mortality and major morbidity in a group of patients with left ventricular dysfunction. Two large, separate trials were run concurrently as part of SOLVD: 1) a prevention trial of patients with low ejection fraction but no overt symptoms of CHF and, 2) a treatment trial of patients with low ejection fraction and symptoms of CHF. In addition, patients at selected sites were entered into substudies to evaluate the effect of enalapril on a number of intermiediate outcomes such as right and left ventricular function and hemodynamics, LV mass and wall stress, hormones, arrhythmias, exercise capacity, and quality of life in subsets of patients. Lastly, a registry of 6,336 pateints with congestive heart failure of LV dysfunction was designed to describe the clinical course of an unselected group of patients.

Background:

Congestive Heart Failure (CHF) is a major and increasingly recognized public health problem. The recognition that patients with CHF often have elevated peripheral vascular resistance has led to the introduction of vasodilator therapy, which has emerged as an important component of its treatment. Of the vasodilators, the angiotensin-converting enzyme (ACE) inhibitors appeared to be the most promising. In 1985 little was known about the impact of any long-term drug treatment on survival.

Subjects:

There were two basic criteria for participants: 1) age between 21 and 80 years, inclusive, and 2) LV ejection fraction of less than or equal to 0.35, performed within 3 months of the day of consent. Ejection Fraction was assessed by 1 of 3 techniques: 1) radionuclide LV angiography; 2) LV contrast angiography, and 3) 2-dimensional echocardiography with ejection fraction calculated by the area length method or Simpson's rule. A total of 2,569 patients were enrolled into the treatment study and 4,228 patients were enrolled in the prevention study. The limited access dataset available through the NHLBI contains the prevention and treatment study data and not the registry data.

Conclusions:

In the prevention trial, a significant reduction in the incidence of heart failure and the rate of related hospitalizations was observed for patients in the enalapril arm. A statistically significant reduction in mortality was not observed in the enalapril treatment arm; however, there was a trend toward fewer total deaths and deaths due to cardiovascular causes among the enalapril patients. (N Engl J Med 1992; 327:685-91.)