For more information regarding BMS clinical trial participation, please visit www.BMSStudyConnect.com Inclusion Criteria: - Adults with either active or a history of non-valvular atrial fibrillation or flutter with the planned or existing use of an oral anticoagulant for prophylaxis of thromboembolism. In addition, subjects must have had an acute coronary syndrome or percutaneous coronary intervention with a stent within the prior 14 days - Planned use of antiplatelet agents for at least 1 to 6 months - Males and Females ≥ 18 years of age - Women of childbearing potential must have a negative serum or urine pregnancy test within 24 hours prior to the start of study drug Exclusion Criteria: - Conditions other than atrial fibrillation that require chronic anticoagulation. (e.g. prosthetic mechanical heart valve) - Severe renal insufficiency (serum creatinine > 2.5 mg/dL or a calculated creatinine clearance < 30 mL/min - Patients with a history of intracranial hemorrhage - Patients have had or will undergo Coronary arterial bypass graft (CABG) for their index acute coronary syndrome (ACS) event - Patients with known ongoing bleeding and patients with known coagulopathies - Any contraindications or allergies to VKA, apixaban, or to intended P2Y12 antagonists or to aspirin