Effectiveness of bi-atrial pacing for reducing atrial fibrillation after coronary artery bypass graft surgery.

Atrial fibrillation (AF) is common after cardiac surgery and adds significant cost and morbidity. The use of prophylactic pacing strategies to prevent post-operative AF has been controversial. We previously performed a pilot study which suggested that the combination of beta-blockers and bi-atrial pacing (BAP) may reduce AF after cardiac surgery. We prospectively randomized 118 patients to continuous BAP for up to 96 hours post-operatively versus standard therapy. All patients were treated with beta-blockers as tolerated. Patients were paced in the AAI mode at a rate of 100 pulses per minute. The primary endpoint of the study was the occurrence of sustained AF (>10 minutes). There was a significant reduction in the incidence of AF in the BAP group among patients undergoing coronary artery bypass graft surgery with or without aortic valve replacement (35 % vs. 19 % AF; OR=0.38, 95 % CI 0.15, 0.93; p <0.05). Including patients undergoing isolated aortic valve surgery (n=7), there remained a strong trend toward a reduction of AF with pacing (no atrial pacing [NAP] vs. BAP; 35 % vs. 21 % AF; OR=0.48, 95 % CI 0.21, 1.11; p=0.08). Patients age 70 or greater benefited most from pacing (NAP vs. BAP; 55 vs. 25 % AF; p<0.05), while those less than 70 years of age did not (17 vs. 18 % p=NS). There was a significant reduction in the amount of time spent in the intensive care unit among patients receiving BAP (50+/-40 vs. 37+/-25 h; p<0.05).BAP together with beta-blockade after coronary artery bypass graft surgery reduces the incidence of post-operative atrial AF. Elderly patients (age 70 or greater) appear to benefit most, and may be a group to whom this therapy should be targeted.

RCT Entities:   Population Interventions Outcomes