Background: Contradictory findings have been reported regarding the safety and efficacy of digitalis in patients recovering from acute myocardial infarction (MI). We studied the association of digitalis use with long-term and short-term prognosis in patients presenting with an acute MI complicated with heart failure (HF), left ventricular dysfunction, or both.
Methods and results: Using the High-Risk MI Database Initiative combining data from 4 major clinical trials, totaling 27,673 patients, we investigated the association between digitalis use at baseline (3093 patients with digitalis and 24,580 without) with the rate of all-cause death, sudden cardiac death, cardiovascular death, HF hospitalization and the combination of the latter two, over a mean follow-up time of 2.7 years. Patients with and without atrial fibrillation (AF) were studied separately. After a propensity score-based analysis, among patients without AF, those receiving digitalis experienced a higher rate of all-cause [hazard ratio (HR) 1.54, 95% confidence interval (CI) 1.42-1.67] and sudden cardiac death (HR 1.65, 95% CI 1.44-1.89), compared to those not receiving digitalis; similar results were found for the other 3 endpoints (all HR around 1.6). In contrast, in AF patients, digitalis had a milder effect on all outcomes (all HR ≤ 1.12), with significant association only for the composite endpoint (HR 1.10, 95% CI 1.00-1.21, p = 0.049); comparable results were obtained at 30 days. Finally, the detrimental effect associated with digitalis use appeared to be more pronounced in patients with ejection fraction ≥ 40%.
Conclusions: In MI survivors with HF and/or systolic dysfunction, digitalis was associated with a significant increased risk of death in patients without AF with mild to neutral associations for patients with AF. These findings raise concerns regarding the safety of digitalis in MI survivors with HF, especially for those without AF.
Keywords: Acute myocardial infarction; Atrial fibrillation; Digitalis; Heart failure; Sudden death; Survival.