Can the Lambre Device Occlude IRRegular And Large Appendages in Patients With Non-Valvular AF

This prospective, randomized, multicenter study will enroll 2,931 subjects (2706 randomized subjects, 225 roll-in subjects) at up to 75 investigational sites in the United States. Patients presenting with non-valvular atrial fibrillation who are at increased risk for stroke and systemic embolism based on CHA2DS2-VASc scores, and who are recommended for oral anticoagulation therapy but have an appropriate rationale to seek a non-pharmacologic alternative to oral anticoagulation, and who meet all eligibility criteria will be enrolled in the study. Subjects will have clinical follow-up in-hospital and at 45 days, 6 months, 12 months, and annually up to 5-years. CT/Imaging or Transesophageal echocardiographic (TEE) follow-up will occur at 45 days and TEE at 1-year. The LAmbre PlusTM Left Atrial Appendage (LAA) Closure System is intended to reduce the risk of thromboembolism from the left atrial appendage (LAA) in patients with nonvalvular atrial fibrillation who: * Are at increased risk for stroke and systemic embolism based on CHADS2 or CHA2DS2-VASc scores and are recommended for oral anticoagulation (OAC) therapy; AND * Are deemed by their physician to be suitable for OAC; AND * Have an appropriate rationale to seek a non-pharmacological alternative to OAC, taking into account the safety and effectiveness of the device compared to OAC