Amiodarone use after acute myocardial infarction complicated by heart failure and/or left ventricular dysfunction may be associated with excess mortality

Abstract

Background: We sought to assess the association of amiodarone use with mortality during consecutive periods in patients with post-acute myocardial infarction with left ventricular systolic dysfunction and/or HF treated with a contemporary medical regimen.

Methods: This study used data from VALIANT, a randomized comparison of valsartan, captopril, or both in patients with acute myocardial infarction with HF and/or left ventricular systolic dysfunction. We compared baseline characteristics of 825 patients treated with amiodarone at randomization with 13,875 patients not treated with amiodarone. Using Cox models, we examined the association of amiodarone use with subsequent mortality during consecutive periods after randomization (days 1-16, 17-45, 46-198, and 199-1096).

Results: Patients treated with amiodarone were older, had higher Killip class, and were more likely to have a history of diabetes mellitus and hypertension. Adjusting for baseline predictors of mortality, we found that amiodarone use was associated with a significant increase in mortality during 3 of the 4 periods: hazard ratio 1.5, 95% CI (1.1-2.0), P = .02, for days 1 to 16; 2.1 (1.5-2.9), P < .001, for days 17 to 45; 1.1 (0.83-1.46), P = .51, for days 46 to 198; and 1.4 (1.2-1.6), P < .001, for days 199 to 1096.

Conclusion: In this study, amiodarone use was associated with excess early and late all-cause and cardiovascular mortality. These observational findings are in contrast to earlier randomized trials of amiodarone and need to be validated prospectively.