【Background and purpose】
The main cause of Embolic Stroke of Undetermined Source (ESUS) has been considered paroxysmal atrial fibrillation (PAF). However, atherosclerotic lesions have been also common among ESUS patients. 3D-computed tomography angiography (3D-CTA) is useful to assess atherosclerotic embolic source of aorta, intra- and extra-cranial arteries. Therefore, we performed 3D-CTA among ESUS patients and determined their possible embolic source.
【Method】
The consecutive 33 patients, who were admitted as acute ischemic stroke from January 2016 to January 2018, diagnosed as ESUS according to the definition of Hart et al., and underwent 3D-CTA with 320-row multi-detector CT, were enrolled. We assessed ascending aorta, aortic arch, three branches of aortic arch and plaques in intra-extracranial arteries. High risk plaque was defined as non-calcification protruding plaque (≧4mm) or ulcerative plaque.
【Result】
We found High risk plaque on ascending aorta or aortic arch in 10 patients (30%). High risk plaque on three branches were observed in 3 patients (2 patients in the brachiocephalic artery, 1 patient in the left subclavian artery). Mild-moderate stenosis (NASCET/WASID <50%) in the ipsilateral side of stroke in the intra-extracranial artery were observed in 5 patients.
【Conclusion】
We found that 42% patients of ESUS had atherosclerotic lesions in aorta and intra-extracranial artery which was suggested as the cause of stroke.
3D-CTA is useful to identify the cause of ESUS.

3D-CTA is useful to identify underlying cause of Embolic Stroke of Undetermined Source