Atrial pacing periablation for prevention of paroxysmal atrial fibrillation

Background-This study tested the hypothesis that rate-adaptive atrial pacin g would prevent paroxysmal atrial fibrillation (PAF) in patients with frequ ent PAF in the absence of symptomatic bradycardia. Methods and Results-Patients (n=97) with antiarrhythmic drug-refractory PAF received a Medtronic Thera DR pacemaker 3 months before planned AV node ab lation. Patients were randomized to no pacing (n=48) or to atrial rate-adap tive pacing (n=49), After a 2-week stabilization period, patients were foll owed up for an additional 10 weeks. The time to first recurrence of sustain ed PAF, the interval between successive episodes of PAF, and the frequency of PAF were compared between the 2 groups in intention-to-treat analysis. T ime to first episode of sustained PAF was similar in the no-pacing (4.2 day s; 95% CI, 1.8 to 9.5) and the atrial-pacing (1.9 days; 95% CI, 0.8 to 4.6; P=NS) groups. PAF burden was lower in the no-pacing (0.24 h/d; 95% CI, 0.1 0 to 0.56) than in the atrial-pacing (0.67 h/d; 95% CI, 0.30 to 1.52; P=0.0 8) group. Paired crossover analysis in 11 patients revealed that time to fi rst PAF was shorter during atrial pacing (1.6 days; 95% CI, 0.6 to 4.9) tha n with no pacing (6.0 days; 95% CI, 2.4 to 15.0; P=0.13), and PAF burden wa s greater during atrial pacing (1.00 h/d; 95% CI, 0.35 to 2.91) than with n o pacing (0.32 h/d; 95% CI, 0.09 to 1.13; P<0.016), Conclusions-Atrial rate-adaptive pacing does not prevent PAF over the short term in patients with antiarrhythmic drug-resistant PAF without symptomati c bradycardia.