Abstract 18131: Canadian Multi-center Experience With WATCHMAN for Percutaneous Left Atrial Appendage Closure

Abstract

Background: There is limited data with WATCHMAN for left atrial appendage (LAA) closure in patients with nonvalvular atrial fibrillation (AF) and contraindications to anticoagulation. The purpose of this study was to evaluate the safety and efficacy of WATCHMAN in our early Canadian experience. Methods: We report our consecutive series of patients who underwent WATCHMAN implantation at 4 Canadian centers (Vancouver General Hospital, Montreal Heart Institute, Hamilton General Hospital and Ottawa Heart Institute). Indications for LAA closure were CHADS2≥1, and contraindication/intolerance to or failure on anticoagulation. All cases were done under general anesthesia and TEE guidance. Majority of patients received dual antiplatelet therapy (DAPT) for 3-6 months after implant. Follow-up TEE was typically performed at 1-6 months post-procedure. Results: Ninety patients underwent LAA closure with WATCHMAN from May 2013 to June 2015. The mean age was 75.0 ± 7.9. The mean CHADS2 score was 2.9 ± 1.2, CHADS-VASc score was 4.4 ± 1.5, and HASBLED score was 3.2 ± 1.2. Permanent AF was present in 66.7% and paroxysmal AF in 33.3%. Indications for LAA closure were prior bleeding in 81 patients (90.0%; 74 major bleeding, and 7 minor bleeding), 9 were deemed high-risk for bleeding (renal failure, cirrhosis, labile INR, esophageal ulcers, on DAPT), and 1 with recurrent strokes on warfarin. Procedural success was 97.8% (88/90), with one device embolization (snared percutaneously) and one implant failure due to inadequate LAA depth. There was no procedural stroke/TIA, death, MI, or cardiac tamponade. There were 3 major bleeding that required transfusions. Mean hospital stay was 1.4 ± 1.8 days. Antithrombotic therapy post-implant included DAPT in 66/90 (73.3%), anticoagulant in 21/90 (5 warfarin, 16 direct anticoagulant), and aspirin alone in 3/90. Follow-up TEE was available in 53 patients, there was 1 device-associated thrombus (treated successfully with anticoagulation), and 18 peri-device leaks (all <5mm). Mean follow-up was 173.8 ± 117.3 days, with no stroke or death, but there was 1 TIA and 3 major bleeding. Conclusion: In our early Canadian experience, WATCHMAN for LAA closure in patients contraindicated to anticoagulation is safe and effective.