In this open-label, prospective, randomized pilot study, patients who develop atrial fibrillation after isolated coronary artery bypass grafting surgery will be identified. Patients with persistent atrial fibrillation (>12 hours) or recurrent sustained atrial fibrillation (>2 episodes of atrial fibrillation lasting longer than 30 minutes) will be candidates for inclusion. Upon meeting study inclusion and exclusion criteria, and after informed consent, patients will be randomized to either the standard of care (warfarin per protocol) or apixaban arms of the trial. Routine postoperative care after CABG will occur in both groups. Upon discharge, anticoagulation in both groups will be managed by the anticoagulation clinic. Patients will be followed for 30 days after surgery.
- Coronary Artery Bypass Grafting
- Deep Venous Thrombosis
- Systemic Embolism
- Postoperative Atrial Fibrilation
- Warfarin (Coumadin®)Drug
Intervention Desc: Study arm that patient can be randomized to. Warfarin therapy has been the mainstay of therapy for patients with POAF. While the duration of therapy is usually short (3-4 weeks), complications of anticoagulation do occur. Additionally, warfarin therapy for POAF is associated with increased length of stay, need for monitoring, and bleeding complications. ARM 1: Kind: Experimental Label: Warfarin Description: While patients are hospitalized, warfarin will be dosed daily, with daily INR monitoring per hospital protocol. Daily doses may vary from 0.5mg to 15mg by mouth, as determined by patient specific factors such as patient size, hepatic function, INR, concomitant medications, diet, or other factors. Based on these factors or others not listed, there may also be days in which the patient is prescribed to not get does not receive a dose of warfarin. After discharge from the hospital, warfarin dosing will be subsequently managed by an anticoagulation clinic, per established protocols. All patients will have a goal INR of 2-3 during the duration of the study. The duration of therapy will be at least 30 days. The patient's physician may determine that anticoagulation therapy should be continued after the study period, based on their examination of the patient at the 30-day post-operative examination.
- Apixaban Drug
Intervention Desc: Study arm that patient can be randomized to. Apixaban is a novel, orally active, potent, direct selective inhibitor of coagulation FXa that directly and reversibly binds to the active site of FXa and exerts anticoagulant and antithrombotic effects by diminishing the conversion of prothrombin to thrombin. ARM 1: Kind: Experimental Label: Apixaban Description: Apixaban is to be dosed at 5 mg by mouth twice daily, except in the case of the criteria listed below in "dose modifications". The duration of therapy will be at least 30 days. The patient's physician may determine that anticoagulation therapy should be continued after the study period, based on their examination of the patient at the 30-day post-operative examination.
- Allocation: Randomized
- Masking: Open Label
- Purpose: Prevention
- Endpoint: Safety/Efficacy Study
- Intervention: Parallel Assignment
|Type||Measure||Time Frame||Safety Issue|
|Primary||Freedom from stroke or thromboembolic event||30 days||Yes|
|Secondary||Units of blood given after initiation of anticoagulation medication||30 days||No|
|Secondary||Total post-operative length of stay||30 days||No|
|Secondary||Duration from diagnosis of post-operative atrial fibrillation (POAF) to discharge from the hospital||30 days||No|
|Secondary||Time in therapeutic range of INR, if on warfarin||30 days||No|
|Secondary||Patient compliance percentage to apixaban||30 days||No|