Anticoagulation in ischemic stroke: opportunities in arterial disease

In the acute phase of ischemic stroke, there is no evidence that anticoagulants provide any benefit in terms of death or dependency. A small reduction in the incidence of recurrent stroke is offset by an equally small increase in intracranial hemorrhage (ICH). In the secondary prevention of stroke, in patients with transient ischemic attacks (TIAs) and moderately disabling ischemic stroke, the relative risk reduction of major vascular events by aspirin is rather modest: 13% (or 19% in a systematic review of arterial disease in general). Anticoagulants might well offer stronger protection, since they provide a 35-50% risk reduction after myocardial infarction or in patients with TIAs or nondisabling ischemic stroke in the presence of atrial fibrillation. Meanwhile, it has become clear that anticoagulation with high intensity (INR 3.0-4.5) is associated with a high risk of ICH in patients with cerebral ischemia who are in sinus rhythm, while INR values around 1.9 do not offer protection against major vascular events. An international clinical trial of anticoagulation with INR values between 2.0 and 3.0 (ESPRIT) is still in progress. In cerebral venous sinus thrombosis, anticoagulant treatment is associated with a nonsignificant reduction of the risk of death or dependence, but the treatment has nevertheless become widely adopted because it seems safe: no increase in the proportion of patients with hemorrhagic transformation of infarction has so far been demonstrated.