Background: Surgical or percutaneous occlusion of the left atrial appendage (LAA) is increasingly used for thromboembolic protection in atrial fibrillation. Incomplete LAA closure may increase risk of thrombosis and thromboembolism, and therefore approaches to address residual communications are needed. Objective: To analyze the technique of closing an incompletely occluded LAA and subsequent patient outcomes. Methods: We performed a retrospective analysis of 5 consecutive patients who presented for completion of LAA closure. Results: Four patients were male, mean age 75, average CHA2DS2-VASc score 5.4, and four had prior surgical LAA ligation. One patient had previously had a WATCHMAN device placed for whom a 3D printed model was created from preprocedural imaging data to guide Amplatzer occluder device selection for closure. The residual LAA communication maximal diameter averaged 6.2 mm (range 5-8mm). In 4 of 5 cases, an ablation catheter was used to enter the LAA. The residual LAA communication was closed with either an Amplatzer occluder (n=3) or a WATCHMAN device (n=2). No procedural complications occurred, and no residual leak remained afterwards. No neurologic events occurred during follow up (average 603 days, range 155-1177 days). Anticoagulation or dual antiplatelet therapy was stopped following a transesophageal echo (TEE) ³ 6 weeks after the procedure demonstrated no residual communication in 4 of 5 patients, and after 20 weeks in the fifth patient without a follow up TEE. Conclusion: Large residual LAA communications after LAA occlusion attempts can be successfully and safely closed percutaneously using either Amplatzer occluder devices or WATCHMAN devices.

ABSTRACT Background: Data regarding the use of high-power short-duration (HPSD) radiofrequency (RF) in combination with half-normal saline irrigation for catheter irrigation is limited. Objectives: This study investigated the safety and efficacy of using HPSD RF ablation in combination with half-normal saline irrigation for the treatment of AF. Methods: One hundred consecutive patients with AF underwent RF ablation using HPSD combined with half-normal saline for catheter irrigation. In addition, the following ablation strategies were used: 1 mm tags for the display of ablation lesions on the mapping system, high-frequency jet ventilation (HFJV), low contact force, pacing after ablation to verify areas of noncapture, atrial/ventricular pacing at 500 to 700 ms to aid in catheter stability, use of two skin electrodes to reduce impedance, and post-ablation adenosine infusion. Power was started at 40-45 W and was modulated manually based on impedance changes. Results: The average age of patients was 65.2 years and 70% were male. Forty-seven percent had paroxysmal AF and the average CHA2DS2-VASc score was 2.1±1.6. The average power and lesion duration were 38.1 ± 3.3 W and 8.1 ± 2.3 seconds, respectively. During a median follow-up period of 321 + 139 days, 89% of the patients remained free from any atrial arrhythmias after a single RF ablation procedure. No procedure-related death, stroke, pericardial effusion, or atrioesophageal fistula occurred during follow-up. Conclusions: Catheter ablation using HPSD RF lesions in combination with half-normal saline irrigation and is safe and effective, and results in high rate of freedom from AF.