Abstract WP181: Preprocedual Carotid Plaque Characterization by Duplex Ultrasonography as a Predictor of in-Stent Intimal Restenosis 6 months After Carotid Stenting

Abstract

Background and Purpose: In-stent intimal restenosis (ISR) caused by neo-intimal hyperplasia generally occurs <24 months after carotid stenting (CAS). Although the real clinical impact of ISR are still unclear, several studies suggested the development of ISR significantly correlated with ipsilateral stroke and death. Also differences in the rate of ISR between open-cell and closed-cell stents have yet to be well evaluated. We aimed to investigate predictors of ISR 6 months after CAS. Methods: We examined 133 patients (mean age of 72.1±8.4 years old) received CAS in a single hospital during 2014 and 2018. Preoperative carotid plaque evaluation was performed by carotid angiography, duplex carotid ultrasonography (CUS), and black-blood carotid artery MRI (BB-MRI). Mean stenosis rate (NASCET) was 71.0±12.3% (44%-100%). Follow-up carotid angiography was performed six months after CAS in all patients according to a predefined protocol. ISR was defined as in-stent intimal hyperplasia more than 50% stenosis based on the NASCET method. Selection of stent type was at the discretion of the treating physician. Predictors of ISR were determined by multivariate logistic regression analysis. Results: Follow-up angiography demonstrated ISR in 33 patients (24.8%). In 44 patients, more than 2 stents were deployed. Univariate analyses demonstrated hypoechoic plaque, 1 mobile plaque with jerry fish sign, complete occlusive or pseudo occlusive lesion, closed-cell stent are significantly associated with ISR (>50%), however no association was observed in traditional risk factors, MRI plaque characterization, and implantation of multiple stents. Multivariate analysis demonstrated low echoic plaque in preoperative CUS (OR4.67; 95%CI, 1.85-11.78) and closed-cell stent (OR 0.378; 95%CI, 0.15-0.97) as significant predictors of ISR. Conclusions: Preprocedual plaque characterization by CUS but not MRI appeared to be useful to predict ISR 6 months after CAS even after adjustment of stent type.