Effects of Amiodarone and Thoracic Epidural Analgesia on Atrial Fibrillation After Coronary Artery Bypass Grafting

Objective: This study was designed to assess the effects of a perioperative dosing regimen of amiodarone administration, high thoracic epidural anesthesia (TEA), or a combination of the 2 regimens on atrial fibrillation (AF) after coronary artery bypass grafting (CABG).

Design And Setting: The study was prospective, controlled, and randomized and was performed in a tertiary health care center associated with a university.

Participants: One hundred sixty-three patients scheduled for coronary artery bypass graft surgery.

Interventions: In this 2 x 2 factorial-designed study the patients were randomized to 1 of 4 regimens in which group E had perioperative TEA, group E+A had TEA and amiodarone, group A had amiodarone, and group C served as control. The epidural catheter was inserted at T1-3 the day before surgery. TEA groups received TEA for 96 hours. The amiodarone regimen consisted of a single loading dose of 1,800 mg of amiodarone orally. Intravenous infusion of amiodarone was started after induction of anesthesia and was administered at 900 mg over 24 hours for the subsequent 3 days.

Measurements And Main Results: AF was documented using Holter monitoring. In group E 22 of 44 (50%), in group E+A 10 of 35 (28.6%), in group A 10 of 36 (27.8%), and in the control group 20 of 48 (41.7%) patients developed AF (odds ratio amiodarone/nonamiodarone 0.47 [0.24-0.90]; P = 0.02).

Conclusions: The perioperative amiodarone regimen used in this study was effective in reducing the incidence of AF after CABG while TEA was not.