Apixaban as a Secondary Prophylaxis Agent for Patent Foramen Ovale-Associated Stroke

Background: The purpose of this case report is to describe a case of switching warfarin to apixaban in a patient on anticoagulant prophylaxis for a patent foramen ovale (PFO)-associated stroke. Case Summary: An 86-year-old Afro-Latina female with a past medical history of cerebrovascular accident (CVA) in 2012 secondary to PFO and diagnosed Atrial Fibrillation (AF). Patient was switched from warfarin to apixaban after 3 months of labile international normalized ratio (INR) levels. The patient's INR was monitored at a pharmacist-led anticoagulation clinic. As the patient's INR remained subtherapeutic while on warfarin, a shared decision was made to switch the patient to apixaban 2.5 mg twice daily due to consistently painful enoxaparin injections, inconsistent vitamin K intake, frequent clinic visits and unstable renal function. Patient tolerated the anticoagulant switch well and reported satisfaction with decreased clinic visits and variable vitamin K diet. At 12 months post-switch, the patient's complete blood count remains stable, no reported signs and symptoms of bleeding, and no new CVA or venous thromboembolism (VTE) events identified. Based on an improvement in renal function, the dose was increased to 5 mg twice daily.