The proximal aorta: a source of stroke.

The availability of the sophisticated imaging techniques of transoesophageal echocardiography and epiaortic ultrasound scanning have drawn attention to the ascending aorta and aortic arch as a potential source of embolic stroke. Several studies have shown an association between atheroma in this region and cerebral ischaemic events. Although aortic atheroma is associated with vascular disease in other arterial territories, two large controlled studies have shown it to be a risk factor for stroke, independently of other major risk factors such as carotid vascular disease, cardiac disease and hypertension. In observational and case-control studies, the risk of stroke is higher in the presence of certain echocardiographic appearances of atheromatous plaque--these include plaque thickness of > 4-5 mm, surface irregularity suggesting plaque ulceration and mobile elements suggesting superimposed thrombus. However, longitudinal studies are required to evaluate the prognostic significance of such findings. Several therapeutic options have been described or suggested in patients with and without stroke in whom aortic atheroma is demonstrated, but the optimal management of such patients is yet to be determined in prospective controlled trials.