Does preoperative atrial fibrillation influence early and late outcomes of coronary artery bypass grafting?

Objective: The study objective was to describe the independent effect of preoperative atrial fibrillation on the outcome of coronary artery bypass grafting, including the causes of death (cardiac vs noncardiac).

Methods: We analyzed the outcome of patients with preoperative atrial fibrillation who underwent on-pump coronary artery bypass grafting between 1993 and 2002 and compared them with matched controls in sinus rhythm; matching variables were age, gender, ejection fraction, and numbers of diseased coronary arteries and distal anastomoses. Direct patient follow-up focused on late complications and reinterventions, and we investigated causes for all deaths.

Results: Operative mortality (1.6% vs 1.9%, P = .79) was similar in patients with preoperative atrial fibrillation (n = 257) compared with patients in sinus rhythm (n = 269). The patients with atrial fibrillation had longer hospital stays (9 +/- 6 days vs 8 +/- 6 days, P = .0008) and a trend to more frequent early readmissions (13% vs 9%, P = .08). During follow-up (median 6.7 years, maximum 12 years), late hospital admission was more frequent in patients with atrial fibrillation (59% vs 31%, P < .0001). Risk of late mortality (all causes) in patients with atrial fibrillation was increased by 40% compared with patients in sinus rhythm (P = 0.02), and the late cardiac death rate in the atrial fibrillation group was 2.8 times that of the sinus rhythm group (P = .0004). Major adverse cardiac events occurred in 70% of patients with preoperative atrial fibrillation compared with 52% of patients in preoperative sinus rhythm (P < .0001). Subsequent rhythm-related intervention, including pacemaker implantations, was more common in the atrial fibrillation group (relative risk = 2.1, P = .0027).

Conclusions: Uncorrected preoperative atrial fibrillation in patients undergoing coronary artery bypass grafting is associated with increased late cardiac morbidity and mortality and poor long-term survival. These data support consideration of atrial fibrillation surgery at the time of coronary artery bypass grafting.