Introduction: Despite amiodarone's established safety profile in the setting of heart failure, it is unknown whether its impact on cardiovascular outcomes in patients with atrial fibrillation is modulated by left ventricular function.
Methods and results: A pooled analysis of 3,307 patients (age 68.0 ± 0.2 years; 31.1% female) enrolled in AFFIRM and AF-CHF trials was conducted to assess the effect of rhythm control with amiodarone on cardiovascular outcomes, according to left ventricular systolic function. In amiodarone-treated patients (N = 1,107), freedom from recurrent atrial fibrillation was 84% and 45% at 1 and 5 years, respectively, with no differences according to left ventricular function (P = 0.8754). Similarly, the adjusted proportion of time spent in atrial fibrillation (15.0 ± 1.8%) did not vary according to ventricular function (P = 0.6094). Over 40.0 ± 0.3 months of follow-up, 1,963 (59.4%) patients required at least one hospitalization, 1,401 (42.6%) of whom had cardiovascular-related hospitalizations. Adjusted all-cause and cardiovascular hospitalization rates were similar with amiodarone versus rate control in all patients and in subgroups with and without severe left ventricular dysfunction. A total of 729 (22.0%) patients died, 498 (15.1%) from cardiovascular causes. Adjusted all-cause and cardiovascular mortality rates were similar with amiodarone versus rate control overall and in subgroups with and without severe left ventricular dysfunction.
Conclusion: Amiodarone's efficacy in maintaining sinus rhythm and reducing the burden of atrial fibrillation is similar in the presence or absence of severe left ventricular dysfunction. Rhythm control with amiodarone is associated with comparable hospitalization and mortality rates to rate control in patients with and without left ventricular dysfunction.
Keywords: AF-CHF trial; AFFIRM trial; amiodarone; antiarrhythmic drug; atrial fibrillation; heart failure.
© 2014 Wiley Periodicals, Inc.