Prevalence and Characteristics of Carotid Artery High‐Risk Atherosclerotic Plaques in Chinese Patients With Cerebrovascular Symptoms: A Chinese Atherosclerosis Risk Evaluation II Study

Background Carotid atherosclerotic plaque rupture is an important source of ischemic stroke. However, the prevalence of high‐risk plaque ( HRP ) defined as plaques with luminal surface disruption, a lipid‐rich necrotic core occupying >40% of the wall, or intraplaque hemorrhage in Chinese population remains unclear. This study uses carotid magnetic resonance imaging ( CMRI ) to investigate HRP prevalence in carotid arteries of Chinese patients with cerebrovascular symptoms. Methods and Results Patients with cerebral ischemic symptoms in the anterior circulation within 2 weeks and carotid plaque determined by ultrasound were recruited and underwent CMRI . The HRP features were identified and compared between symptomatic and asymptomatic arteries. Receiver‐operating‐characteristic analysis was used to calculate area‐under‐the‐curve ( AUC ) of stenosis and maximum wall thickness for discriminating presence of HRP . In 1047 recruited subjects, HRP detected by CMRI was nearly 1.5 times more prevalent than severe stenosis (≥50%) in this cohort (28% versus 19%, P <0.0001). Approximately two thirds of HRP s were found in arteries with <50% stenosis. The prevalence of HRP in symptomatic carotid arteries was significantly higher than that of the contralateral asymptomatic carotid arteries (23.0% versus 16.4%, P =0.001). Maximum wall thickness was found to be a stronger discriminator than stenosis for HRP ( AUC : 0.93 versus 0.81, P <0.0001). Conclusions There are significantly more high‐risk carotid plaques than carotid arteries with ≥50% stenosis in symptomatic Chinese patients. A substantial number of HRPs were found in arteries with lower grade stenosis and maximum wall thickness was a stronger indicator for HRP than luminal stenosis. Clinical Trial Registration URL : https://www.clinicaltrials.gov/ . Unique identifier: NCT 02017756.