Embolism from the aortic arch in patients with cerebral ischemia.

The pathogenic role of aortic arch atherosclerosis (AAA) in embolic stroke is not well understood. We investigated, prospectively, the prevalence and severity of AAA in patients with embolic stroke to ascertain its role as a risk factor for cerebral ischemia. We examined 100 consecutive patients who had experienced acute symptoms due to cerebral ischemia. Clinical examination, electrocardiogram, x-ray, ultrasound examination of craniocervical arteries, transesophageal echocardiography (TEE), cranial computerized tomography, and magnetic resonance imaging were undertaken. Seventy-five patients showed evidence of AAA; 34 patients had moderate to severe (> 5 mm thickening) AAA. Age was positively related to the severity of AAA, as were smoking, coronary heart disease, diabetes mellitus, internal carotid artery (ICA) occlusive disease, and embologenic heart disease. Hypertension, which was evident in 52 patients, did not distinguish those cases showing AAA. Twelve patients showed evidence of high-degree ICA stenosis on the symptomatic side, although the extent of ICA stenosis and AAA were unrelated. A cardiac source of emboli was found in 28 patients. AAA was found to be the probable source for embolic stroke in 14 patients. These data indicate that aortic arch atherosclerosis is an important source of cerebral emboli which may increase the risk for ischemic stroke. Furthermore, we suggest that TEE examination of the aortic arch may be important for the diagnosis of AAA and ultimately for the prophylactic treatment of severe cerebral ischemia.