Atrial pacing for the prevention of atrial fibrillation after cardiovascular surgery

OBJECTIVE The purpose of this study was to determine the efficacy of atrial pacing in the prevention of atrial fibrillation following cardiovascular s urgery. BACKGROND Although pharmacologic therapy has been used to help prevent post operative atrial fibrillation, it suffers from limited efficacy and adverse effects. In the nonoperative setting, novel pacing strategies have been sh own to reduce recurrences of atrial fibrillation and prolong arrhythmia-fre e periods in patients with paroxysmal atrial arrhythmias. METHOD A total of 154 patients (115 men; mean age, 65 +/- 10 years; ejectio n fraction, 53 +/- 10%) undergoing cardiac surgery (coronary artery bypass surgery, 88.3%; aortic valve replacement 4.5%; coronary bypass + aortic val ve replacement, 7.1%) had right and left atrial epicardial pacing electrode s placed at the time of surgery. Patients were randomized to either no paci ng, right atrial (RAP), left atrial (LAP) or biatrial pacing (BAP) for 72 h after surgery. Beta-adrenergic blocking agents were administered concurren tly to all patients following Surgery. RESULTS There was a reduction in the incidence of postoperative atrial fibr illation from 37.5% in patients receiving no postoperative pacing to 17% (p < 0.005) in patients assigned to one of the three pacing strategies. The l ength of hospital stay was reduced by 22% from 7.8 +/- 3.7 days to 6.1 +/- 2.3 days (p = 0.003) in patients assigned to postoperative atrial pacing. T he incidence of atrial fibrillation was lower in each of the paced groups ( RAP, 8%; LAP, 20%; BAP, 26%) compared with patients who did not receive pos toperative pacing (37.5%). CONCLUSION Postoperative atrial pacing, in conjunction with beta-blockade, significantly reduced both the incidence of atrial fibrillation and the len gth of hospital stay following cardiovascular surgery. Additional studies a re needed to determine the most effective anatomic pacing site. (C) 2000 by the American College of Cardiology.