Fibrillation atriale

More than 10% of the population aged over 75 years is concerned by non-valvular permanent atrial fibrillation which is responsible for at least 30% of ischemic strokes. The indication of anticoagulant therapy is discussed in two different situations: primary or secondary prevention of stroke and acute phase of stroke. Patients over 75 years have a high risk of stroke (> 8% year). All the studies have demonstrated the benefit of primary or secondary prevention by antivitamin K with the INR between 2 and 3 (reduction of the relative risk of about 68%). Conversely, the efficacy of aspirin has not been proven in elderly patients. In case of ischemic stroke, it is not recommended to initiate anticoagulation (non fractioned or low molecular weight heparin) within the first hours. Prevention of venous thrombosis remains necessary. Currently, less than 30% of the patients older than 75 years are given anticoagulation, the risk of the treatment being probably overestimated. The risk/benefit ratio should be evaluated more properly.