Evaluating Real-World Clinical Outcomes in Atrial Fibrillation Patients Receiving the WATCHMAN Left Atrial Appendage Closure Technology: Final 2-Year Outcome Data of the EWOLUTION Trial Focusing on History of Stroke and Hemorrhage

Background: Left atrial appendage occlusion with WATCHMAN has emerged as viable alternative to vitamin K antagonists in randomized controlled trials. Evaluating real-life clinical outcomes in atrial fibrillation patients receiving the WATCHMAN left atrial appendage closure technology was designed to collect prospective multicenter outcomes of thromboembolic events, bleeding, and mortality for patients implanted with a WATCHMAN in routine daily practice. Methods: One thousand twenty patients with a WATCHMAN implant procedure were prospectively followed in 47 centers. Left atrial appendage occlusion indication was based on the European Society of Cardiology guidelines. Follow-up and imaging were performed per local practice up to a median follow-up of 2 years. Results: Included population was old (age 73.4±8.9 years), at high risk for stroke (311 prior ischemic stroke/transient ischemic attack and 153 prior hemorrhagic stroke) and bleeding (318 prior major bleeding), with CHA2DS2-VASc score ≥5 in 49%, hypertension, abnormal renal/liver function, stroke, bleeding history or predisposition, Labile international normalized ratio, elderly, drugs/alcohol concomitantly ≥3 in 40% and oral anticoagulation contraindication in 72%. During follow-up, 161 patients (16.4%) died, 22 strokes were observed (1.3/100 patient-years, 83% reduction versus historic data), and 47 major nonprocedural bleeding events (2.7/100 patient-years, 46% reduction versus historic data). Stroke and bleeding rates were consistently lower than historic data in those with prior ischemic (−76% and −41%) or hemorrhagic (−81% and 67%) stroke and prior bleeding (−85% and −30%). Lowest bleeding rates were seen in patients with early discontinuation of dual antiplatelet therapy. Patients with early discontinuation of antithrombotic therapy showed lower bleeding rates, while they were highest for those with prior bleeding. Device thrombus was observed in 34 patients (4.1%) and was not correlated to drug regimen during follow-up (P=0.28). Conclusions: During the complete 2-year follow-up of Evaluating Real-Life Clinical Outcomes in Atrial Fibrillation Patients Receiving the WATCHMAN Left Atrial Appendage Closure Technology, patients with a WATCHMAN left atrial appendage occlusion device had consistently low rates of stroke and nonprocedural bleeding, although most were contraindicated to oral anticoagulation and used only single antiplatelet therapy or nothing. Clinical Trial Registration: URL: https://clinicaltrials.gov. Unique identifier: NCT01972282.