[Atherosclerotic aortic plaques and risk of embolic stroke]

There is mounting evidence to implicate complex atherosclerotic aortic plaques as a significant independent risk factor for embolic stroke. Ulcerated plaques at autopsy, plaques thicker than 4 to 5mm at transesophageal echocardiography and those with mobile components are more likely to be associated with stroke. Mobile thrombus in the lumen may be a source of cerebral emboli. Among patients with ischemic stroke, those with plaques thicker than 4mm in the aortic arch have the highest risk of recurrent stroke, myocardial infarction, other vascular event including vascular death. However, since no randomized trials have been conducted to evaluate the role of any antithrombotic therapies in patients with aortic atheroma, no recommendation can be made regarding the best treatment strategies. Antiplatelet agents, oral anticoagulant, thrombolytic therapy, and elective surgical endarterectomy or graft replacement are all reasonable options that have been proposed and that must be evaluated in term of benefit/risks ratio in specific randomized controlled trials. Meanwhile, antiplatelet agents and aggressive risk factor management appear to be the first line treatment. No recommendation can be made to use oral anticoagulation in these patients nor for a target INR. Concerns also exist on the possibility of anticoagulation driven cholesterol embolism in these patients.