Evaluating the association between vascular remodeling and plaque calcification patterns of the carotid artery and its effects on ischemic symptoms using CT angiography

Background: Arterial remodeling is a compensatory mechanism of the vessel wall in response to atherosclerotic plaque growth. However, the clinical significance of vascular remodeling of carotid lesions remains unclear. Through this study, we aimed to evaluate the association between vascular remodeling and ischemic symptoms in patients with an internal carotid artery (ICA) stenosis degree >= 50%, considering the differences in plaque calcification patterns. Methods: This retrospective cross-sectional study included adult patients with moderate-to-severe proximal ICA stenosis associated with atherosclerotic plaques admitted to the Zhejiang Hospital between September 2018 and March 2023. Parameters such as lumen diameter, plaque calcification types, calcium scores, and calcification thickness were assessed using non-contrast and contrast-enhanced computed tomography angiography (CTA). The remodeling ratio (RR) was calculated by dividing the maximum distance of the proximal ICA between the inner border of the arterial lumen at the plaque site and the outer borders of the plaque by the luminal diameter. Atherosclerosis risk factors and medications were recorded. The Mann-Whitney U test or chi-square test was used to compare the differences between groups. Correlations were measured using Pearson's correlation coefficient. Predictors of ischemic symptoms were assessed using multivariable logistic regression analysis, with results expressed as odds ratio (ORs) with 95% confidence intervals (CIs). A P value less than 0.05 (two-sided) was considered to indicate statistical significance The differences in RR among plaque calcification types and the association between vascular remodeling and clinical symptoms were analyzed. Results: A total of 242 ICAs in 196 patients were included in this study, and 84 were symptomatic and 158 were asymptomatic. The RR in symptomatic ICA [median, 1.31 (interquartile range, 1.17-1.68)] was significantly greater than that in asymptomatic group [median, 1.20 (interquartile range, 1.05-1.45)], P=0.006). Significant differences in RR existed among plaque calcification types, among which type 5 and 6 plaques had the highest RR. About 71.5% (173/242) of all ICAs showed positive remodeling. Significant correlations were observed between RR and ischemic symptoms and between positive remodeling and calcification thickness (P<0.05 for all variables). On multivariable logistic regression analysis, calcification thickness remained significantly associated with positive remodeling of carotid arteries (OR 2.30; 95% CI: 1.06-5.01; P=0.036). Conclusions: Arterial remodeling exists in the ICA. A significant association between arterial positive remodeling and plaque calcification thickness was established. RR helps predict ischemic symptoms. The results of our study suggest that arterial remodeling serves as a novel measure to help ascertain the risk stratification of ischemic events in carotid atherosclerotic disease.