Amiodarone as a first-choice drug for restoring sinus rhythm in patients with atrial fibrillation - A randomized, controlled study

Study objectives: To investigate the efficacy and safety of amiodarone admi nistered as the drug of first choice in the conversion of atrial fibrillati on, regardless of its duration. Design: Prospective, randomized, controlled clinical study. Setting: Tertiary cardiac referral center. Patients: Two-hundred eight consecutive patients (102 men; mean [+/- SD] ag e, 65 +/- 10 years) with atrial fibrillation. Interventions: One-hundred eight patients received amiodarone, and 100 pati ents received placebo treatment. patients randomized to amiodarone received 300 mg IV for 1 h, and then 20 mg/kg for 24 h. They were also given 600 mg /d orally, divided into three doses, for 1 week, and thereafter 400 mg/d fo r 3 weeks. Patients randomized to placebo treatment received an identical a mount of saline solution IV over 24 h, and oral placebo treatment for 1 mon th. Measurements and results: Baseline clinical characteristics were similar in the two groups. Conversion to sinus rhythm was achieved in 87 of 108 patie nts (80.05%) who received amiodarone, and in 40 of 100 patients (40%) in th e placebo group (p < 0.0001). Statistical analysis showed that the duration of the arrhythmia and the size of the left atrium affected both the likeli hood of conversion to sinus rhythm and the time to conversion in both group s. No side effects requiring discontinuation of treatment were observed in either group. Conclusions: Amiodarone appears to be safe and effective in the termination of atrial fibrillation. However, extreme cases with a large left atrium an d long-lasting arrhythmia need long-term therapy.