Atherosclerotic Aortic Arch Plaques in Cryptogenic Stroke: A Microembolic Signal Monitoring Study

Abstract

Background and Purpose: To find out the prevalence of relevant atherosclerotic plaques in the aortic arch and their potential role as a source of embolism in cryptogenic stroke. Methods: We performed a transoesophageal echocardiography (TEE) on 49 patients with cryptogenic stroke from a total series of 212 non-selected patients with acute ischaemic stroke studied prospectively by cranial computed tomography (CT), colour-duplex and transcranial Doppler (TCD) sonography with micro-embolic signal (MES) monitoring. Cryptogenic stroke was diagnosed in those patients without carotid or intracranial stenosis >50%, nor lacunar or cardio-embolic strokes. We defined relevant plaques as those ≧4 mm thick located in the ascending aorta or proximal arch. Results: Twenty-three patients (46.9%) had atherosclerotic aortic plaques (AAP): 3 in the ascending aorta (in 1 ≧4 mm), 11 in the proximal aortic arch (in 4 ≧4 mm) and 9 in the descending aorta (in 5 ≧4 mm). Hence, 5 patients (10.2%) had relevant plaques. Aortic plaques were significantly related to older age (p < 0.001) and male gender (p = 0.042). A carotid artery stenosis <50% was found in 39% of patients with AAP and in 8% of those without AAP (p = 0.009). MES were detected in 3 patients with plaques ≧4 mm thick, but not in those without AAP or with AAP <4 mm thick (p = 0.006). Conclusion: Although few patients with cryptogenic stroke had relevant plaques in our non-selected population, our results support the hypothesis that relevant aortic plaques have embolic potential.