Randomized crossover comparison of DDDR versus VDD pacing after atrioventricular junction ablation for prevention of atrial fibrillation

Background-Some clinical data suggest that atrial-based pacing prevents par oxysmal atrial fibrillation (AF). This study tested the hypothesis that DDD R pacing compared with VDD pacing prevents AF after atrioventricular (AV) j unction ablation. Methods and Results-Patients were randomized to DDDR pacing (n=33) or to VD D pacing (n=34) after AV junction ablation and followed every 2 months for 6 months. Patients then crossed over to the alternate pacing mode and were followed for an additional 6 months. Primary analysis included the time to first recurrence of sustained AF (duration >5 minutes), total AF burden, an d the development of permanent AF. The time to first episode of AF was simi lar in the DDDR group (0.37 days, 95% CI 0.1 to 1.3 days) and the VDD pacin g group (0.5 days, 95% CI 0.2 to 1.7 days, P=NS), AF burden increased over time in both groups (P<0.01), At the 6-month follow-up, AF burden was 6.93 h/d (95% CI 4.37 to 10.96 h/d) in the DDDR group and 6.30 h/d (95% CI 3.99 to 9.94 h/d) in the VDD group (P=NS), Twelve (35%) patients in the DDDR gro up and 11 (32%) patients in the VDD group had permanent AF within 6 months of ablation. Within 1 year of follow-up, 43% of patients had permanent AF, Conclusions-DDDR pacing compared with VDD pacing does not prevent paroxysma l AF over the long term in patients in the absence of antiarrhythmic drug t herapy after total AV junction ablation. Many patients have permanent AF wi thin the first year after ablation.