Trial of Apixaban vs Warfarin in Reducing Rate of Cognitive Decline, Silent Cerebral Infarcts and Cerebral Microbleeds in Patients With Atrial Fibrillation

Randomized Trial of Apixaban vs Dose Adjusted Warfarin in Reducing Rate of Cognitive Function Decline, Silent Cerebral Infarcts and Cerebral Microbleeds in Non-valvular Atrial Fibrillation Patients With CHA2DS2-VaSc Score = 2

The investigators' central hypothesis is that in patients with atrial fibrillation, anticoagulation with Apixaban reduces the rate of decline in cognitive function, when compared to Warfarin. The investigators also hypothesize that Apixaban reduces cognitive decline by reducing the rate of new cerebral infarction and cerebral microbleeds detected by cerebral MRI compared to warfarin.

Inclusion Criteria:

• Non-valvular Atrial Fibrillation
• CHA2DS2-VASc Score > or = to 2
• Never been treated with Apixaban (Eliquis) or prior treatment of < 1 month
• Candidate for oral anticoagulation as assessed by a treating physician

Exclusion Criteria:

• Valvular Atrial Fibrillation (Rheumatic valve disease,Moderate or greater mitral stenosis,Mechanical cardiac valve)
• Active Bleeding
• Prior treatment with Apixaban >1 month
• Recent stroke within 7 days
• Dementia
• Implanted devices not compatible with MRI/any cardiac implanted device
• Claustrophobia
• Active alcohol/drug abuse
• Life expectancy < 1 year
• Taking asprin with >100mg doses
• Known hypersensitivity to warfarin or Apixaban
• Severe renal insufficiency
• Prior severe bleeding (Intracranial bleeding (subdural, subarachnoid, intraparenchymal bleeding),GI bleed requiring transfusion,Bleeding from other sites requiring transfusion)
• Psychosocial reasons that make study participation impractical
• Currently enrolled in another IND or IDE trial that has not completed the primary endpoint or that clinically interferes with the current study endpoints
• Co-morbid condition(s) that could limit the subject's ability to participate in the trial or to comply with follow-up requirements, or that could impact the scientific integrity of the study.
• Prisoners or subjects who are involuntarily incarcerated
• Subjects who are compulsorily detained for treatment of either psychiatric or physical illness
• Current or expected systemic treatment with strong dual inhibitors of CYP3A4 and P-gp (Any one of rifampin, carbamazepine, phenytoin, St. John's Wort, ketoconazole, itraconazole, ritonavir, clarithromycin)
• Need for dual anti-platelet therapy with aspirin and another agent such as thienopyridine