Failure of non-vitamin K antagonist oral anticoagulants in preventing stroke in elderly patient: a case report of multiple strokes on standard of care treatment for atrial fibrillation.

Atrial fibrillation (AF) is the most common type of treated heart arrhythmia. Generally, the treatment goals for atrial fibrillation are to reset the rhythm or control the rate and prevent the development and subsequent embolization of atrial thrombi. These thromboembolic events can occur with any kind of atrial fibrillation that is paroxysmal, persistent or permanent. In patients who are candidate for anticoagulation therapy, major practice guideline provides vitamin K antagonist (VKA) oral anticoagulant and non-VKA oral anticoagulants as treatment options. The risk of AF increases with age and despite treatment on standard of care anticoagulation therapy, recrudescent cardioembolic events may still arise especially in the elderly as we will see in this case.