Potential unwrapping of the LAA post implant with clinically significant leaks.

The purpose of this study is to compare the safety and effectiveness of Laminar Left Atrial Appendage Closure (LAAC) device as compared to the commercially available LAAC devices in participants with non-valvular atrial fibrillation (NVAF) to reduce the risk of stroke (blocked blood vessel or bleeding in brain) and systemic embolism (blockage in a blood vessel harming vital organs).

This prospective, randomized, controlled, multicenter, open-label pivotal clinical study will enroll participants with non-valvular atrial fibrillation who are eligible for short-term anticoagulation therapy but have a rationale to seek non-pharmacologic alternative. Participants will be randomized 1:1 to the Laminar Left Atrial Appendage Closure System or commercially available device (WATCHMAN™ left atrial appendage closure device / Amulet™ left atrial appendage occluder).

Inclusion Criteria:

• Documented evidence of paroxysmal, persistent, or permanent non-valvular atrial fibrillation (NVAF)
• CHA2DS2-VASc score greater than or equal to (>=) 2 in men and >= 3 in women
• Deemed to be clinically indicated for left atrial appendage (LAA) closure by the Site Investigator and a clinician not a part of the procedural team using an evidence-based decision-making tool in accordance with standard of care
• Recommended for chronic oral anticoagulation therapy (OAC) but has an appropriate rationale to seek a non-pharmacologic alternative
• Eligible for the protocol-specified post-procedural antithrombotic regimen
• Willing and able to comply with the protocol, and has provided written informed consent (participant or legally authorized representative) per institutional review board (IRB) requirements

Exclusion Criteria:

• Single episode, transient, or reversible atrial fibrillation (AF) (example, secondary to thyroid disorders, acute alcohol intoxication, trauma, recent major surgical procedures)
• Prior cardiac surgery or any procedure that involved pericardial access
• Stage IV kidney disease or Renal insufficiency, defined as estimated glomerular filtration rate (eGFR) less than (<) 30 milliliters per minute per (mL/min)/1.73 square meters (m^2) or participants with end stage renal disease who are dialysis dependent
• Any cardiac or non-cardiac interventional or surgical procedures within 60 days prior to or any planned general surgery, cardiac surgery, or interventional procedure within 60 days after implant (including, but not limited to cardioversion, percutaneous coronary intervention (PCI), cardiac ablation, cataract surgery)
• Left atrial appendage anatomy which cannot accommodate either commercially available control device or the laminar implant per manufacturer instructions for use (IFU) (that is, the anatomy and sizing must be appropriate for a control and the Laminar device to be enrolled in the study)