Vascularization of carotid plaque in recently symptomatic patients is associated with the occurrence of transcranial microembolic signals

Background and purpose: Microembolic signals (MES) are detectable in the middle cerebral artery by transcranial ultrasound downstream to atherosclerotic lesions of the internal carotid artery (ICA) in patients with stroke or transient ischaemic attack. The occurrence of MES predicts future risk of stroke in patients with symptomatic and asymptomatic carotid stenosis. The detection of intra-plaque neovascularization by contrast-enhanced ultrasound (CEUS) in atherosclerotic plaques of the ICA is associated with future cardiovascular/cerebrovascular events. We investigated whether there is an association between both surrogate markers of future vascular events. Methods: Forty-one patients with symptomatic atherosclerotic plaques underwent ipsilateral transcranial ultrasound MES detection for 30 min followed by a CEUS investigation of the plaque. The occurrence and number of MES was documented, and the degree of intra-plaque neo-vascularization was measured semi-quantitatively. Results: During the 30 min investigation, 17 patients had MES and nine of them showed neo-vascularization of the atherosclerotic plaque. The remaining 24 patients did not have MES, and only in four patients of this group could plaque neo-vascularization be demonstrated (P = 0.020). Conclusions: We found an association between the occurrence of MES and the presence of neo-vascularization in patients with symptomatic atherosclerotic carotid plaque. Therefore, plaque neo-vascularization might also be a surrogate marker of future stroke risk.