Abstract 14764: Left Atrial Appendage Function and Risk of Stroke After Left Atrial Appendage Electrical Isolation in Patients With Long-Standing Persistent AF: Results From the BELIEF Randomized Trial

Introduction: The Belief Randomized trial sought to assess whether the empirical isolation of the left atrial appendage (LAA) in addition to an extensive ablation could improve success at follow up in patients with long standing persistent (LSP) atrial fibrillation (AF). The aim of this sub-analysis of the trial aimed to evaluate the LAA contraction at the 6 month repeat Trans-esophageal echocardiogram (TEE). Methods: Patients with LSP AF undergoing ablation were enrolled and randomly assigned to undergo empirical LAA isolation along with an extensive ablation or extensive ablation alone. All patients undergoing LAA isolation received a TEE at the 6 months follow up, irrespective of their underlying rhythm. We evaluated TEE parameters and compared thromboembolic complication between groups. Results: We enrolled 173 pts with average age of 63.8 ± 8.5 years and 85.5% male pts. LAA isolation was performed in 101 pts. LAA was not isolated in 72 pts. Follow-up TEE was performed in all pts with LAA isolation. The peak flow velocity in the appendage was low (<0.4 m/s) in 56.4% (57/101) patients. The doppler across the mitral valve demonstrated E-wave to A-wave ratio (E/A) of 2.64 ± 1.4. All patients had E/A >1, out of which 55.4 %( 56/101) had E/A > 2 (p=0.16). One (1.2%) LAA thrombus [Oral anticoagulant warfarin INR subtherapeutic] and 1 (1.2%) LAA smoke [Oral anticoagulant warfarin, INR : 2.24] were detected in the LAA isolation group as an incidental finding at TEE before redo ablation procedure. One patient (0.99%) had stroke in the LAA isolation group after warfarin discontinuation due to a surgical procedure, while 3 (4.2%) stoke/TIA occurred (p=0.31) in the no LAA isolation group (2 pts on warfarin, 1 pt on aspirin). Conclusion: The results of this study show that LAA isolation does not increase the risk of tia/stroke at follow up. This risk appears to be related to the compliance to oral anticoagulation.