Atrial Fibrillation Predicts Worse Long Time Prognosis after CABG – A 6-Year Survival Analysis

Background: Postoperative atrial fibrillation occurs in 5% - 65% of patients undergoing cardiac surgery. Although postoperative atrial fibrillation is often regarded as a temporary, benign, operation-related problem, it is associated with a two- to threefold increased risk of adverse events, including permanent or transient stroke, acute myocardial infarction, and death. Methods: Two hundred and fifty eligible consecutively enrolled coronary artery bypass grafting patients were included in the randomized, controlled, double-blinded trial RASCABG. That study showed a safe, practical, feasible, and effective prophylactic amiodarone regimen, which significantly decreased the risk of atrial fibrillation with 14% (5.0 - 24) from 26% to 11%, with the number needed to treat 6.9 (4.2 - 20). This study is a 6-year follow-up study regarding the long-term prognostic factor of postoperative atrial fibrillation, amiodarone prophylaxis and diabetes mellitus. Results: The long-term 6-year mortality risk of postoperative atrial fibrillation was 31% equally distributed among patients in the active and in the placebo prophylactic group. The 6-year mortality risk in the sinus rhythm group was 18% likewise equally distributed, whereas the 6-year mortality risk in the background population was approximately 8%. The 6-year mortality risk of diabetes mellitus was 33% equally distributed, whereas the excluded off pump coronary artery bypass group experiences an increased 6-year mortality risk of 47%. Conclusions: Postoperative prophylaxis with a high dose of oral amiodarone after an intravenous bolus infusion is a safe, practical, feasible, and effective regimen for Coronary Artery Bypass Grafting patients in a 6-year long-term perspective. Atrial fibrillation and diabetes mellitus is correlated to increased mortality risk.