Background: There have been significant advances in the treatment of patients with cardiomyopathy with reduced ejection fraction (EF <40%). However, there is a dearth of information in the treatment of patients with cardiomyopathy and mid-range ejection fraction (EF 40 to 50%). Current guidelines state to treat these patients as patients with cardiomyopathy and preserved ejection fraction. The Prevention of Events with Angiotensin Converting Enzyme Inhibition (PEACE) trial was conducted on patients with stable coronary artery disease and normal or slightly reduced left ventricular function to evaluate the benefit of an ACE inhibitor, trandolapril, versus modern conventional therapy. This trial did not show any advantage from treating these subjects with an ACE inhibitor. Our goal is to elucidate further whether ACE inhibitors reduce death in patients with cardiomyopathy and mid-range ejection fraction.
Methods: PEACE Trial data was used to evaluate the effect of ACE inhibitors in a subgroup of patients with cardiomyopathy and mid-range ejection fraction (40-50%). A chi-square test and a t-test were used to examine and compare the binary and continuous variables of demographic and health characteristics between experimental and comparison groups. A chi-square test was used to compare the difference in outcomes between the two groups. The statistical analyses were performed using SAS version 9.4. All tests were conducted using an α=0.05 as the probability of a Type I error.
Results: We studied a subgroup of subjects from the PEACE trial with cardiomyopathy and mid-range ejection fraction (n=2512 of 8290 total subjects). Subjects were randomly assigned to the interventional group (n=1247) and the placebo group (n=1265). There were no significant differences in baseline demographic and health characteristics between the two groups. The risks of composite outcomes (death from cardiovascular causes, death from noncardiovascular causes, nonfatal myocardial infarction, and stroke) (RR 0.88, 95% CI 0.78-0.99; P=0.03) and death from any causes (RR 0.85, 95% CI 0.73-0.99; P=0.03) were lower in subjects treated with trandolapril.
Conclusion: This study unveiled the benefit of ACE inhibitors among patients with cardiomyopathy and mid-range EF.