Early pharmacologic conversion of atrial fibrillation after off-pump coronary artery bypass grafting

Background The aim of this study was to evaluate the efficacy of early amiodarone-based pharmacological cardioversion for postoperative atrial fibrillation (POAF) following off-pump coronary bypass grafting (OPCAB). Methods A total of 507 patients who underwent OPCAB between 2015 and 2017 were categorized into POAF (n=94) and no-POAF (n=413) groups. Patients in the POAF group were treated according to the following institutional protocol: 150 mg loading dose of intravenous amiodarone, followed by oral administration with sequential maintenance doses at 600, 400, and 200 mg per day. If sinus rhythm was restored before discharge, patients were discharged without amiodarone or anticoagulants, except for dual antiplatelets. Results Before discharge at index hospitalization, 97.8% of POAF patients had restored sinus rhythm. Independent risk factors for POAF were age, unstable angina, prior percutaneous transluminal coronary angioplasty, and left atrial diameter. The mean follow-up duration was 41.1±12.8 months. Freedom from overall mortality and composite events, including mortality, major bleeding requiring admission and cerebrovascular events, were similar between the 2 groups. Results were consistent after propensity-score matching. Conclusions Amiodarone-based rapid pharmacological cardioversion of POAF resulted in a high sinus rhythm conversion rate (97.9%). Rate of late adverse cardiovascular events including stroke, were low even without anticoagulation. As optimal treatment and anticoagulation guidelines for POAF after OPCAB have not yet been established, amiodarone-based treatment protocols may be considered as a useful option.