Another value of TEE in the evaluation of cryptogenic stroke is the assessment of atheromatous disease of the aorta. Several studies have evaluated the role of various imaging techniques in the diagnosis of atheromatous aortic disease. Aortography provides only an inexact view of the aortic lumen, without clear identification of the endothelial surface. CT scanning and MRI can provide an enhanced evaluation; however, the imaging is not performed in real time. TEE is ideally suited to providing high-resolution real-time imaging, which also provides atherosclerotic plaque morphology and mobility, as well as the dynamic effect of flow. Various authors36–40
have reported significant aortic atheroma in up to 50 to 60% of patients with unexplained stroke. Stroke risk is highest, however, with the identification of large (ie, > 4 to 5 mm), mobile, and ulcerated plaques.,36–40
Investigators have used various grading systems for aortic atheroma, and, to date, no single unified system has been widely accepted. All systems agree, however, that the highest risk patients are those with mobile plaques, ulcerated plaques, and plaques that protrude into the aorta by > 4 to 5 mm. As such, these plaque characteristics should be specifically reported in any patient undergoing TEE. We have chosen the following system to grade atheromatous disease of the aorta identified by TEE: grade 1, minimal intimal thickening; grade 2, extensive intimal thickening; grade 3, sessile atheroma of < 4 mm; grade 4, protruding atheroma of ≥ 4 mm; and grade 5, mobile or ulcerated atheroma.