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

Abstract

BackgroundCarotid 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 ResultsPatients 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 HRPs 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).ConclusionsThere 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: NCT02017756.

Atherosclerosis in stroke‐related vascular beds and stroke risk: A 3‐D MR vessel wall imaging study

“…5,28 A recent cross-sectional study showed that 16.6% symptomatic carotid arteries had IPH. 21 We found the intracranial artery IPH in our study population was more prevalent than that in previous studies. Xu et al 5 reported that the intracranial artery IPH was detected in 15.8% symptomatic patients.…”

“…19 Investigators utilized twodimensional (2-D) MR vessel wall imaging to identify atherosclerotic plaques in symptomatic patients and found that the prevalence of carotid plaques was 66.7%. 20 Most recently, with 2-D MR vessel wall imaging, Zhao et al 21 found that more than 60% of carotid high-risk plaques developed lower grade stenosis (stenosis <50%). In carotid artery MR vessel wall imaging, traditional 2-D protocol only provides less than 40 mm of longitudinal coverage centered to the bifurcation and could not capture the plaques occurred in more distal or proximal arterial segments.…”

Association of severity between carotid and intracranial artery atherosclerosis

“…This may be due to our dominant recruitment of patients with mild stenosis (stenosis <50%). It has been proven that the prevalence of IPH will increase with severity of carotid artery stenosis …”

Carotid Vessel Wall Imaging on CTA

“…A simple linear measurement of the greatest plaque thickness can be a strong discriminator in identifying high-risk plaque (Fig 3), even better than the degree of stenosis. 48 Studies have shown that greater overall plaque thickness is associated with cerebrovascular ischemic symptoms, even in patients with strokes of an undetermined source. [48][49][50][51] While an exact threshold of total plaque thickness to determine increased plaque vulnerability has not been established, it may be in the 2.5to 3-mm thickness range.…”