The CONFORM Pivotal Trial

The CLAAS® device will be evaluated for safety and efficacy by establishing its performance is non-inferior to the commercially available WATCHMAN® and Amulet™ left atrial appendage closure devices in patients with non-valvular atrial fibrillation. Patients who are eligible for the trial will be randomized to receive either the CLAAS device or the WATCHMAN or Amulet™ devices and will be followed for 5 years after device implant.

Inclusion Criteria: 1. Male or non-pregnant female aged ≥18 years 2. Documented non-valvular AF (paroxysmal, persistent, or permanent) 3. High risk of stroke or systemic embolism, defined as CHA2DS2-VASc score of ≥ 3 4. Has an appropriate rationale to seek a non-pharmacologic alternative to long-term oral anticoagulation 5. Deemed by the site investigator to be suitable for short term oral anticoagulation therapy but deemed less favorable for long-term oral anticoagulation therapy. 6. Deemed appropriate for LAA closure by the site investigator and a clinician not a part of the procedural team using a shared decision-making process in accordance with standard of care 7. Able to comply with the protocol-specified medication regimen and follow-up evaluations 8. The subject (or legally authorized representative, where allowed) has been informed of the nature of the study, agrees to its provisions, and has provided written informed consent approved by the appropriate institutional review board (IRB)/Regional Ethics Board (REB)/Ethics Committee (EC). Exclusion Criteria: 1. Pregnant or nursing patients and those who plan pregnancy in the period up to one year following the index procedure. Female patients of childbearing potential must have a negative pregnancy test (per site standard test) within 7 days prior to index procedure. 2. Anatomic conditions that would prevent performance of an LAA occlusion procedure (e.g., atrial septal defect (ASD) requiring closure, high-risk patent foramen ovale (PFO) requiring closure, a highly mobile inter-atrial septal aneurysm precluding a safe TSP, presence of a PFO/ASD closure device, history of surgical ASD repair or history of surgical LAAO closure) 3. Atrial fibrillation that is defined by a single occurrence or that is transient or reversible (e.g., secondary thyroid disorders, acute alcohol intoxication, trauma, recent major surgical procedures) 4. A medical condition (other than atrial fibrillation) that mandates long-term oral anticoagulation (e.g., history of unprovoked deep vein thrombosis or pulmonary embolism, or prosthetic mechanical heart valve) 5. History of bleeding diathesis or coagulopathy, or patients in whom antiplatelet and/or anticoagulant therapy is contraindicated 6. Documented active systemic infection 7. Symptomatic carotid artery disease (defined as \>50% stenosis with symptoms of ipsilateral transient or visual TIA evidenced by amaurosis fugax, ipsilateral hemispheric TIAs or ipsilateral stroke); if subject has a history of carotid stent or endarterectomy the subject is eligible if there is \20) 7. Moderate or severe mitral valve stenosis (mitral valve area \