Contrast-Enhanced Ultrasound Imaging of Carotid Plaque Neovascularization Is Useful for Identifying High-Risk Patients With Coronary Artery Disease

Background: Contrast-enhanced ultrasound (CEUS) in the carotid artery has potential as a technique for imaging plaque neovascularization. This study examined whether CEUS could provide information on the severity and instability of coronary artery disease (CAD). Methods and Results: A total of 304 patients with CAD and carotid plaque underwent CEUS examination of the carotid artery. Intraplaque neovascularization was identified on the basis of microbubbles within the plaque and graded as: G0, not visible; G1, moderate; or G2, extensive microbubbles. The complexity and extent of the coronary lesions were assessed angiographically. A higher grade of CEUS-assessed plaque neovascularization of the carotid artery was associated significantly with greater complexity (rho=0.48 by Spearman's rank correlation test) and extent (rho=0.51) of coronary lesions. G2 plaque neovascularization was a risk for acute coronary syndrome, independent of traditional risk factors (odds ratio 1.91, 95% confidence interval 1.04-3.53, P<0.01). Subgroup analysis showed that carotid CEUS-assessed neovascularization regressed in 12 (46%) of 26 plaques in patients during 6 months of statin treatment, whereas regression occurred in 2 (14%) of 14 plaques in patients not taking a statin (P=0.04, Chi-square test). Conclusions: CEUS examination of the carotid artery may provide valuable information on the severity and instability of CAD and also the efficacy of antiatherosclerotic treatment.