Relation between postoperative mortality and atrial fibrillation before surgical revascularization - 3-year follow-up

Background: Preoperative atrial fibrillation is one of the predictors of increased morbidity and mortality in patients undergoing surgical revascularization, and consequently, prolongs the duration of stay in the ICU and of overall hospitalization. Methods: The study included 3000 patients subjected to primary isolated coronary artery bypass grafting from 2000 to 2004. Of the 3000 patients, 5.8% (n = 174) had electrocardiographically documented, preoperative atrial fibrillation. To evaluate the relationship between preoperative AF and postoperative outcome, all patients were observed for about three years. Results: Patients with preoperative atrial fibrillation were older (p < 0.05), had a lower ejection fraction (p < 0.001), a higher incidence of heart failure (p < 0.001), hypertension (p < 0.001), and more coexistent morbidities including diabetes (p < 0.05), obturative pulmonary disease (p < 0.0001) and mild renal failure (p < 0.001). Statistical analysis showed that survival rates at 6 and 30 days, 6 and 12 months, and 3 years following surgical revascularization of patients with vs. those without preoperative atrial fibrillation were: 96.4% vs. 98.1%, and 94.5% vs. 97.3% (p = ns), 86.2% vs. 93.0% (p < 0.03), and 74.7% vs. 91.0% (p < 0.02), and 70.7% vs. 90.6% (p < 0.01). After 3 years' observation there was a survival difference of 19.9%. We showed that preoperative atrial fibrillation triple increased the risk of postoperative AF and was an independent risk factor for in-hospital death (p < 0.001). Conclusions: Preoperative atrial fibrillation is a predictor of postoperative complications, including death, and of a significant reduction in patients' long-term survival. Patients with preoperative atrial fibrillation should be considered as high-risk patients with potential postoperative complications and should be well protected with antiarrhythmic and anticoagulant therapy.