Inclusion Criteria1. At least one year post-successful catheter ablation for AF or left atrial flutter/tachycardia without evidence of any clinically apparent arrhythmia recurrence based on at least one 24 hour Holter and ECG within 6 months after the last ablation procedure and at least one 24 hour Holter and ECG between 6 and 12 months post-ablation or beyond.
2. Patient must have no atrial fibrillation, atrial flutter or atrial tachycardia > 30 seconds detected on a minimum 48 hour Holter monitor within two months prior to enrollment.
3. CHA2DS2-VASc risk score of 1 or more excluding patients in whom female sex or vascular disease are their sole risk factor.
4. Patients must be > 18 years of age.
1. does not meet all of the above listed inclusion criteria.
2. unable or unwilling to provide informed consent.
3. included in another clinical trial
4. GFR < 30 mL/min
5. contraindication to oral anticoagulation (OAC)
6. contraindication to magnetic resonance imaging (MRI)
7. metallic prosthetic heart valve
8. non-arrhythmic condition necessitating long-term OAC
9. stroke within one year prior to enrolment