Prophylactic Oral Amiodarone for the Prevention of Arrhythmias That Begin Early After Revascularization, Valve Replacement, or Repair: PAPABEAR: A Randomized Controlled Trial

CONTEXT Atrial tachyarrhythmias after cardiac surgery are associated with adverse outcomes and increased costs. Previous trials of amiodarone prophylaxis, while promising, were relatively small and yielded conflicting results. OBJECTIVE To determine whether a brief perioperative course of oral amiodarone is an effective and safe prophylaxis for atrial tachyarrhythmias after cardiac surgery overall and in important subgroups. DESIGN, SETTING, AND PATIENTS Double-blind randomized controlled trial of 601 patients listed for nonemergent coronary artery bypass graft (CABG) surgery and/or valve replacement/repair surgery between February 1, 1999, and September 26, 2003, at a tertiary care hospital. The patients were followed up for 1 year. INTERVENTION Oral amiodarone (10 mg/kg daily) or placebo administered 6 days prior to surgery through 6 days after surgery (13 days). Randomization was stratified for subgroups defined by age, type of surgery, and use of preoperative β-blockers. MAIN OUTCOME MEASURE Incidence of atrial tachyarrhythmias lasting 5 minutes or longer that prompted therapy by the sixth postoperative day. RESULTS Atrial tachyarrhythmias occurred in fewer amiodarone patients (48/299; 16.1%) than in placebo patients (89/302; 29.5%) overall (hazard ratio [HR], 0.52; 95% confidence interval [CI], 0.34-0.69; P