Abstract 15059: Prevalence of Recovery of Conduction in the Left Atrial Appendage Following Electrical Isolation of the Appendage in Patients With Atrial Fibrillation

Background: Electrical isolation of the left atrial appendage (LAAEI) is considered in patients presenting with recurrence following effective PV isolation. Objective: We evaluated the prevalence of LAA reconnection following LAAEI in patients undergoing repeat procedure for AF recurrence. Methods: Consecutive AF patients undergoing repeat ablation for arrhythmia recurrence following LAAEI were included in this analysis. Transesophageal echocardiogram (TEE) was performed in all at baseline to evaluate LAA function. Isoproterenol infusion up to 30 μg/min for 10 to 15 min was administered to detect LAA triggers. Re-isolation of the LAA was performed if triggers were detected. Off-drug success rate was assessed in all. Results: A total of 594 post-LAAEI patients with recurrent AF were included in the analysis. At the redo, PVs were found to be electrically silent in all. LAA reconnection was detected in 214 (36%) patients. Baseline TEE revealed normal LAA contractility and flow-velocity in all. Re-isolation of the LAA was performed in these 214 patients. In patients with no LAA reconnection (n=380), non-PV triggers from other sites were targeted for ablation. There was no difference in the clinical characteristics of patients with vs. without LAA reconnection (Table). At 2 years after the repeat procedure, 201 (94%) patients with and 351 (92.3%) without LAA reconnection were arrhythmia-free off-drugs (p=0.47). Conclusion: In this series, LAA reconnection rate was 36% after single LAAEI procedure and re-isolation of the appendage led to high success rate. Additionally, normal LAA functions detected by TEE correctly predicted recovery of conduction in the LAA.