Background: Incomplete left atrial appendage closure (LAA) due to significant residual leaks may be observed either acutely and/or chronically after Watchman implantation. Although a vigorous tug or retrieval/reimplantation may correct a suboptimal device position during the procedure, those maneuvers may increase the risk of LAA traumatic injury and procedural complications. Endothelial denudation by means of radiofrequency energy applications (RFAs) has been proven to prevent recanalization of intracranial aneurysms after coil embolization. In vitro and in vivo experiments have demonstrated that endothelial denudation promotes collagen deposition and tissue retraction.
Objective: We sought to evaluate the safety and efficacy of RFAs targeting the atrial side of a significant residual leak in patients with acute and chronic evidence of incomplete percutaneous LAA occlusion.
Methods: Twenty-two consecutive patients (mean age: 72±6 yrs; CHA₂DS₂-VASc: 3.4±0.6; HAS-BLED: 3.3±0.8) undergoing a left-sided ablation in combination (12 pts) or after (10 pts) LAA occlusion were included. All had transesophageal echocardiographic (TEE) evidence of a leak ≥ 5mm after Watchman deployment and received multiple RFAs targeting the atrial side of the leak. Peri-Watchman ablation was performed under TEE guidance using a 3.5mm open irrigated-tip ablation catheter. Follow-up TEE was performed approximately 45 days after the procedure to document the presence and size of a residual LAA patency, device stability, and thrombus formation on device.
Results: Peri- or post-procedural TEE documented a severe leak in all patients (mean size: 5.7±0.7mm). On average, 5.9±1.2 RFA (45W, mean duration of each RFA: 10.7±2.1s) were performed targeting the atrial edge of the leak under TEE guidance. Post-RFA leak size was 1.1±0.9mm. No peri-procedural complications were observed. Follow-up TEE revealed complete LAA sealing in 13 cases and a negligible residual leak (1-2mm) in 9. No device dislodgments or thromboses were documented.
Conclusion: RFAs targeting the atrial edge of a significant peri-Watchman leak may promote LAA sealing via tissue remodeling, without increasing complications.