Durability of posterior wall isolation after catheter ablation among patients with recurrent atrial fibrillation

Background: Electrical posterior wall isolation (PWI) is increasingly being used for the treatment of patients with atrial fibrillation (AF). Few data exist on the durability of PWI using current technology.

Objective: The purpose of this study was to characterize the frequency and location of posterior wall reconnection at the time of repeat catheter ablation for AF.

Methods: We performed a single-center retrospective cohort study of 50 patients undergoing repeat AF ablation after previous PWI. Durability of PWI was assessed at the time of repeat ablation based on posterior wall entrance and exit block. Sites of posterior wall reconnection were characterized based on review of recorded electrical signals and electroanatomic maps.

Results: At the time of repeat ablation, mean age was 67 ± 10 years, 31 of 50 patients had persistent AF, and mean CHA₂DS₂-VASc score was 3.0 ± 1.8. Of the 50 patients, 30 had durable PWI at repeat ablation, 1.4 ± 1.6 years after the index procedure. Patients with posterior wall reconnection required repeat ablation earlier (0.9 ± 0.6 years vs1.8 ± 1.9 years from index PWI; P = .048) and were more likely to have atypical atrial flutter (55% vs 27%; P = .043). Among patients with posterior wall reconnection, the roof was the most common site of reconnection (14/20), and 12 patients had multiple regions of reconnection noted.

Conclusion: Posterior wall reconnection is noted in 40% of patients undergoing repeat ablation after an index PWI. The roof of the left atrium is the most common site of posterior wall reconnection.