Impact of preoperative atrial fibrillation on the late outcome of off-pump coronary artery bypass surgery.

OBJECTIVE The impact of pre-existing atrial fibrillation on the long-term outcome in patients after off-pump coronary revascularisation is not well known. This study aims to determine the independent effects of preoperative atrial fibrillation on the early and late outcomes of off-pump coronary artery bypass surgery. METHODS A total of 513 patients undergoing isolated coronary artery bypass surgery using off-pump approach between 2000 and 2005 were studied. Twenty-six of them (5.1%) had preoperative atrial fibrillation (15 had paroxysmal atrial fibrillation and 11 had persistent or permanent atrial fibrillation) and the other 487 patients were in normal sinus rhythm. Early and late outcomes were compared retrospectively between patients with preoperative atrial fibrillation and patients in sinus rhythm. The median follow-up period for the entire study population was 3.3 + or - 2.7 years. RESULTS The baseline characteristics of the patients with preoperative atrial fibrillation were generally similar to those of patients in sinus rhythm. However, the patients with atrial fibrillation had a significantly lower left ventricular ejection fraction compared with those in sinus rhythm (50 + or - 15 vs 56 + or - 12%, p=0.03). The mean age of the atrial fibrillation group was almost 3 years more than that of the sinus rhythm group. Operative mortality was similar in patients with atrial fibrillation (3.8%) and those in sinus rhythm (1.0%). Ten patients developed cerebral infarction within 7 days after surgery, including one patient (3.8%) from the atrial fibrillation group and nine patients (1.8%) from the sinus rhythm group. Long-term survival was significantly decreased in the atrial fibrillation group (5-year survival: 70 + or - 9.6% vs 87 + or - 1.8%; p=0.0018). Freedom from cerebral complications was also significantly decreased in the atrial fibrillation group (5-year survival: 85 + or - 8.3% vs 95 + or - 1.2%; p=0.0009), but there were no differences in cardiac death and major cardiac adverse events. On Cox proportional hazards regression analysis, preoperative atrial fibrillation was a significant adverse predictor for survival (hazard ratio=3.0, 95% confidence intervals (CIs) 1.3-6.9; p=0.009) and independent predictor of late cerebral infarction (hazard ratio=6.2, 95% CIs 2.0-19.3; p=0.0002). CONCLUSIONS Uncorrected preoperative atrial fibrillation is strongly associated with poor long-term survival and increased late cerebral complications after off-pump coronary artery bypass surgery. Concomitant atrial fibrillation surgery should be considered to improve the long-term results of surgical revascularisation.