150 selected patients will be recruited, who have at least one atherosclerotic plaque in the carotid artery that is thicker than 2.0 mm and which is determined to be uniformly or predominantly echolucent by standard ultrasonography. For each of the plaques, standard ultrasonography will be used to evaluate lesion echogenicity, while contrast-enhanced ultrasonography (CEUS) will be used to perform the visual and quantitative analysis of neovascularization. Each technique will be applied at baseline (at the time of study enrollment) and following 0.5、1 year of Elococumab Injection treatment. During the study, these patients will be treated with Elococumab Injection (1ml:140mg),ih, every two weeks.

Inclusion Criteria:

• 1. have at least one atherosclerotic plaque in the carotid artery that is thicker than 2.0 mm and which is determined to be uniformly or predominantly echolucent by standard ultrasonography;
• 2.patients were referred for optimal medical treatment;
• 3.patients agreed to undergo follow-up CEUS at half-year and 1-year interval.

Exclusion Criteria:

• 1.patients had previous history of cerebral thrombosis or cerebral embolism;
• 2.patients were contraindicated to the usage of contrast media;
• 3.image quality of baseline or follow-up CEUS was severely impaired (in presence of severe artifact, non-diagnostic);
• 4.patients withdrew the informed consents during follow-up;
• 5.patients experienced major adverse cerebrovascular events during follow-up;
• 6.patients refused to undergo follow-up CEUS;
• 7.lost follow-up

A total of 150 eligible coronary atherosclerosis disease patients were anticipated to include in this study.