Abstract 4775: Statins Prevent Poor Short and Mid-term Outcome associated with Post Operative Atrial Fibrillation after Coronary Artery Bypass Grafting
Background: Postoperative atrial fibrillation (POAF) is a frequent complication of coronary artery bypass grafting (CABG) surgery. Although it has been associated with higher postoperative morbidity and costs, POAF is still often considered as a benign complication. The objective of this study was to determine the impact of POAF on both short- and mid-term mortality following isolated CABG.
Methods: We retrospectively analyzed the preoperative and operative data of 6751 consecutive patients undergoing a first isolated CABG in our institution between 2000 and 2007. We analyzed the effect of POAF on operative mortality and mid-term survival using multivariate logistic and Cox regression.
Results: The incidence of POAF was 27.8%. Operative mortality was higher in POAF patients (2.3% vs 0.9%, p<0.001). On multivariate analysis, after adjustment on age and other predictors of mortality, POAF remained an independent predictor of operative mortality (OR=1.72, p=0.02). Patients with POAF also had reduced mid-term survival (6-year survival: 85.4% vs 89.6%; age adjusted HR for mortality = 1.37, p=007). After adjusting for other predictors of mortality, POAF remained significantly associated with reduced mid-term survival (Mortality HR=1.35, p=0.04). In an additional analysis excluding events that occurred within the first year, POAF remained independently associated with lower mid-term survival (HR=1.60, p=0.03). Interestingly, after adjustment for potential confounders, statins had a highly protective effect in POAF patients on both operative mortality (OR=0.39, p=0.004) and mid-term mortality (HR=0.62, p=0.03), whereas they had no significant effect on these outcomes in patients without POAF (OR=2.18, p=0.11, and HR=0.86, p=0.46 respectively).
Conclusion: POAF is an independent risk factor for both short- and mid-term mortality following CABG. Moreover, statin therapy was independently associated with a marked reduction in the POAF-related mortality. These findings suggest that POAF has a negative impact on survival following CABG and that this impact may be reduced by statins.