Enalapril Decreases the Incidence of Atrial Fibrillation in Patients With Left Ventricular Dysfunction

BACKGROUND: Atrial fibrillation (AF) is frequently encountered in patients with heart failure (HF) and is also a predictor of morbidity and mortality in this population. Recent experimental studies have shown electrical and structural atrial remodeling with increased fibrosis in animals with HF and have suggested a preventive effect of ACE inhibitors (ACEi) on the development of AF. To verify the hypothesis that ACEi prevent the development of AF in patients with HF, we conducted a retrospective analysis of the patients from the Montreal Heart Institute (MHI) included in the Studies Of Left Ventricular Dysfunction (SOLVD). METHODS AND RESULTS: Clinical charts were reviewed and serial ECGs interpreted by a single cardiologist blinded to drug allocation. Patients with AF or flutter on the baseline ECG were excluded. Baseline characteristics were obtained from the SOLVD databases. The mean follow-up was 2.9+/-1.0 years. Of the 391 patients randomly assigned at MHI, 374 were in sinus rhythm at the time of random assignment, with 186 taking enalapril and 188 taking placebo. Baseline characteristics were similar in the two groups except for a higher incidence of previous myocardial infarction in the enalapril group. Fifty-five patients had AF during the follow-up: 10 (5.4%) in the enalapril group and 45 (24%) in the placebo group (P<0.0001). By Cox multivariate analysis, enalapril was the most powerful predictor for risk reduction of AF (hazard ratio, 0.22; 95% CI, 0.11 to 0.44; P<0.0001). CONCLUSIONS: Treatment with the ACEi enalapril markedly reduces the risk of development of atrial fibrillation in patients with left ventricular dysfunction.