Optimal Anticoagulation for Higher Risk Patients Post-Catheter Ablation for Atrial Fibrillation Trial

Inclusion Criteria 1. Patient must be at least one year post-successful catheter ablation(s) for atrial fibrillation without evidence of any clinically apparent arrhythmia recurrence defined as all of the following: No AF/AT/AFL on at least 24 hour Holter and an ECG (or equivalent) from 2-6 months after the last ablation, AND no AF/AT/AFL on at least 24 hour Holter and an ECG any time after 6 months after the last ablation AND no AF/AT/AFL on at least 24 hour Holter and ECG 2 months before enrolment in the study. The Holter/ECG within 2 months of enrolment may also serve as the Holter performed 6 months or later after the last ablation - see section 2.3.1 for details. 2. Patient must have a CHA2DS2-VASc risk score of 1 or more. Patients in whom female sex or vascular disease are their sole risk factor may not be enrolled. 3. Patient must be \>18 years of age. 4. Patient must have non-valvular AF. Exclusion Criteria 1. Patient does not meet all of the above listed inclusion criteria. 2. Patient is unable or unwilling to provide informed consent. 3. Patient is included in another randomized clinical trial or a clinical trial requiring an insurance. 4. Patient has been on an investigational drug within 30 days of enrolment. 5. Patient has been on strong CYP3A inducers (such as rifampicin, phenytoin, phenobarbital, or carbamazepine) or strong CYP3A inhibitors (such as ketoconazole or protease inhibitors) within 4 days of enrolment. 6. Patient has creatinine clearance \< 30 mL/min. 7. Patient has bleeding contra-indication to oral anticoagulation (such as bleeding diathesis, hemorrhagic disorder, significant gastrointestinal bleeding within 6 months, intracranial/intraocular/ atraumatic bleeding history, fibrinolysis within 48 hours of enrollment). 8. Patient has other contraindication to oral anticoagulation or treatment with antiplatelet agent (such as allergy). 9. Patient has a contraindication to magnetic resonance imaging (MRI) or is unlikely to tolerate due to severe claustrophobia. 10. Patients with a contraindication to implantation of an implantable loop recorder if the patient opts for a loop recorder as part of the study (such as limited immunocompetence or a wound healing disorder). 11. Patient has valvular atrial fibrillation \[reference AHA guidelines\]. 12. Patient has a non-arrhythmic condition necessitating long-term oral anticoagulation. 13. Patient had a severe, disabling stroke within one year prior to enrollment or any stroke within 14 days of enrollment. 14. Patient with special risk factors for stroke unrelated to AF, specifically known thrombophilia/ hypercoagulability, uncontrolled hypertension (systolic blood pressure \>180 mmHg and/or diastolic blood pressure \>100 mmHg within 4 days of enrollment), untreated familial hyperlipidemia, known vascular anomaly (intracranial aneurysm/ arteriovenous malformation or chronic vascular dissection), or known severe carotid disease. 15. Pregnancy or breastfeeding. 16. Women of childbearing age who refuse to use a highly effective and medically acceptable form of contraception throughout the study. 17. Patients who are \> 85 years of age. 18. Patients who are critically ill or who have a life expectancy \<3 years. 19. Patients for whom the investigator believes that the trial is not in the interest of the patient.