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

Prior treatment

• Patient has been on an investigational drug within 30 days of enrolment.
• 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.
• Patient has other contraindication to oral anticoagulation or treatment with antiplatelet agent (such as allergy).
• Patient had a severe, disabling stroke within one year prior to enrollment or any stroke within 14 days of enrollment.

Other illness

• 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).
• 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).
• Patient has a non-arrhythmic condition necessitating long-term oral anticoagulation.
• 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.

Lab values

• Patient has creatinine clearance \< 30 mL/min.

Age

• Women of childbearing age who refuse to use a highly effective and medically acceptable form of contraception throughout the study.
• Patients who are \> 85 years of age.
• Patients who are critically ill or who have a life expectancy \<3 years.

Other

• Patient does not meet all of the above listed inclusion criteria.
• Patient is unable or unwilling to provide informed consent.
• Patient is included in another randomized clinical trial or a clinical trial requiring an insurance.
• Patient has a contraindication to magnetic resonance imaging (MRI) or is unlikely to tolerate due to severe claustrophobia.
• Patient has valvular atrial fibrillation \[reference AHA guidelines\].
• Pregnancy or breastfeeding.
• Patients for whom the investigator believes that the trial is not in the interest of the patient.

• 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.
• 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.
• Patient must be \>18 years of age.
• Patient must have non-valvular AF.