Assessment of carotid plaque neovascularization using quantitative analysis of contrast-enhanced ultrasound imaging is useful for risk stratification in patients with coronary artery disease

•Carotid plaque neovessels (CPNs) were assessed by contrast-enhanced ultrasound (CEUS).•We developed quantitative analysis of CEUS of CPN.•Quantitative analysis of CEUS of CPN had high reproducibility.•High CPN was a predictor of cardiac events in coronary artery disease.•Quantitative analysis of CEUS of CPN was useful for risk assessment.

BackgroundContrast-enhanced ultrasound (CEUS) of the carotid artery is a potential technique for imaging plaque neovascularization, a feature of unstable atherosclerotic plaques. This study examined whether assessment of intra-plaque neovascularization of the carotid artery using CEUS provides prognostic information in patients with coronary artery disease (CAD).MethodsA total of 206 patients with stable CAD underwent a CEUS examination of the carotid artery and were followed up prospectively for < 38 months or until a cardiac event (cardiac death, non-fatal myocardial infarction (MI), unstable angina pectoris (uAP) requiring unplanned coronary revascularization, or heart failure requiring hospitalization). The degree of contrast signals measured within the carotid plaque was quantified by calculating the mean gray scale level within the region of interest of the carotid plaque, expressed as plaque enhanced intensity.ResultsDuring the follow-up period, 31 events occurred (2 cardiac deaths, 7 non-fatal MIs, 16 uAP, and 6 heart failure). Multivariate Cox proportional hazard analysis showed that plaque enhanced intensity was a significant predictor of cardiac events independent of traditional risk factors (HR, 1.13; 95% CI, 1.05-1.21; p < 0.001). The addition of the plaque enhanced intensity to traditional risk factors resulted in net reclassification improvement (NRI) and integrated discrimination improvement (IDI) (NRI 0.62, p = 0.001; and IDI 0.106, p = 0.002).ConclusionsThe assessment of carotid plaque neovascularization using quantitative analysis of CEUS may be useful for risk stratification in patients with CAD.