Ischemic stroke and non-valvular atrial fibrillation: When to introduce anticoagulant therapy?

About 20 to 30% of ischemic strokes are related to non-valvular atrial fibrillation. This type of situation is particularly at risk for both recurrence of the ischemic event and the hemorrhagic transformation of this stroke. The timing of the introduction or going back to the anticoagulant therapy in these patients remains a difficult issue, with a complex benefit-risk balance that needs to be assessed. Randomized controlled studies are lacking and current recommendations do not allow for clear decision making. The administration of a curative anticoagulant within 72 hours after the event is not recommended in the absence of demonstrated efficacy in preventing recurrence at this stage and because of the risk of intracerebral hemorrhage. This attitude can nevertheless be qualified by a transient accident or ischemic accident of very small size, and in the absence of any other risk factor for intra- or extra-cerebral hemorrhage. From the 4th day, after an appropriate case by case evaluation, the introduction of anticoagulant would be possible within a time which will remain at the appreciation of the medical teams. If the patient's risk of an intracerebral hemorrhage or general bleeding is transiently increased, it will be preferable to wait at least 2 weeks after the stroke. If this risk persists in the long term, the decision of the administration or not of an anticoagulant will have to be made with a multidisciplinary consultation. Vitamin K antagonists or direct oral anticoagulants may be prescribed as first-line therapy for the prevention of recurrence of ischemic stroke in a non-valvular atrial fibrillation patient. The choice will be based on the clinical and biological data of each patient. Direct oral anticoagulants have not shown superiority in the prevention of ischemic recurrence but open up new prospects for earlier treatment if their lesser risk of bleeding is confirmed after further studies.