The Fourth Left Atrial Appendage Occlusion Study

Prior treatment

• Prior left atrial appendage occlusion or removal (surgical or percutaneous)
• Prior percutaneous atrial septal defect or patent foramen ovale closure
• Prior atrial fibrillation ablation unless evidence of recurrent qualifying atrial fibrillation present at least 30 days following ablation
• Individuals being treated with direct thrombin inhibitors

Age

• Age \< 18 years
• Anticipated life-expectancy of \< 2 years

Other

• Current left atrial appendage thrombus
• Planned atrial fibrillation ablation within 90 days of enrollment
• Women of childbearing potential unless they agree to employ effective birth control methods throughout the study
• Patient unable or willing to give informed consent

• (a) Persistent or permanent atrial fibrillation OR (b) Paroxysmal atrial fibrillation in participants with a history of ischemic stroke or systemic embolism
• Increased risk of stroke, defined as a CHA2DS2-VASc stroke risk score of ≥ 4. \[Note: the acronym CHA2DS2-VASc stands for congestive heart failure, hypertension, age ≥75 (doubled), diabetes, stroke (doubled), vascular disease, age 65 to 74 and sex category (female).\]
• Treatment with oral anticoagulants (Vitamin K agonist or factor Xa inhibitor) for at least 90 days prior to enrollment, AND no documented plan to discontinue treatment with oral anticoagulants for the expected duration of the trial.