Study in Atrial Fibrillation (AF) Patients at High Risk of Stroke

Inclusion Criteria: * Written informed consent from the patient, or legally authorized representative, must be obtained before any assessment is performed * Patients with diagnosed AF or atrial flutter(documented on an electrocardiogram or monitor recording) * CHA2DS2-VASc score ≥2 excluding female as a factor * Judged by the investigator to be at increased risk of bleeding because of at least 1 of the following: * Age ≥70on the day of informed consent * Reduced renal function (creatinine clearance \<30mL/min by Cockcroft-Gault) * Chronic use of NSAIDs or antiplatelet agents * Any other condition associated with increased risk such as a prior history of major or clinically relevant nonmajor bleeding, increased fall risk, or frailty * Patients who are not treated with oral anticoagulants (only applies to the initial feasibility cohort) Exclusion Criteria: * Mechanical heart valve or valve disease that is expected to require valve replacement intervention (surgical or invasive) during the course of the registry study * AF due to a reversible cause (eg, cardiac surgery, pulmonary embolism, untreated hyperthyroidism, ethanol use) * Clinical unstable or active endocarditis or endovascular infection * Patients with a medical condition other than AF for which chronic use of an oral anticoagulant is indicated * History of left atrial appendage closure or removal * Life expectancy \<1 year at the time of enrollment as assessed by the investigator * Any medical or psychiatric condition which in the judgment of the Investigator may preclude patients from complying with study requirements for the duration of the study