Differences in Diffusion-Weighted Image and Transesophageal Echocardiographical Findings in Cardiogenic, Paradoxical and Aortogenic Brain Embolism

Abstract

Background and Purpose: The purpose of the present study was to clarify the difference in the infarct topography on diffusion-weighted image (DWI) and cardiac and aortic findings on transesophageal echocardiography (TEE) in stroke patients with different embolic sources. Methods: We studied 270 consecutive patients with acute ischemic stroke who had DWI-documented cortical or subcortical infarcts without significant stenosis of the cerebral arteries. As embolic sources, cardiac diseases, right-to-left shunt diseases and an aortic arch atheroma ≧4.0 mm in thickness were identified using various diagnostic tools including TEE. Results: Seventy-eight (29%) patients had multiple embolic sources. Large infarcts were common in patients in whom cardiac disease was the only embolic source and uncommon in patients in whom aortic atheroma was the only embolic source (p < 0.0001). Vertebrobasilar infarcts were relatively common in patients only having aortic atheromas. Atrial septal aneurysms were more common in patients with a right-to-left shunt than in those with a shunt plus other embolic sources (p = 0.0036). Unique characteristics of the arch atheroma (mobile plaque, extension to branches, or ulcer formation; p < 0.0001) as well as small or moderate-sized infarcts (p = 0.0004) were more common in patients with arch atheromas as the only embolic source than in those with atheromas plus other embolic sources. Conclusions: Embolic stroke patients often have multiple embolic sources. The present study suggests the possibility that embolic stroke has unique clinical features depending on its source. DWI and TEE findings might be helpful in characterizing cardiogenic, paradoxical and aortogenic brain embolism.