Association Between Carotid Plaque Characteristics and Silent New Ipsilateral Ischemic Lesions After Carotid Artery Stenting

Silent new ipsilateral ischemic lesions (sNIIL) detected by diffusion-weighted imaging (DWI) are commonly observed after carotid artery stenting (CAS). We aimed to analyze the association of carotid plaque characteristics on Virtual Histology Intravascular Ultrasound (VH-IVUS) with sNIIL, which is not well understood. Among 128 patients who underwent CAS and VH-IVUS, 112 patients who underwent DWI within 72 h after CAS were included for analysis. VH-IVUS detected cross-sectional composition of plaques including necrotic core (NC), dense calcium (DC), fibrous (FI), and fibrofatty (FF) in each frame. Plaques with ≥3 consecutive thin-cap fibroatheroma (TCFA) or calcified thin-cap fibroatheroma (CaTCFA) frames were defined as vulnerable. Logistic regression was applied to evaluate the association between plaque characteristics and sNIIL. A total of 56 patients (50%) had sNIIL. Larger NC in the maximum NC frame (odds ratio [OR] = 1.35; 95% confidence interval [CI]: 1.03–1.75; P = .029) and defined vulnerable plaques (OR = 3.89; 95% CI: 1.68–9.01; P = .001) were associated with sNIIL. Incidence of sNIIL showed an escalating trend with the increase of quartiles of NC ( P trend = .010). The findings of this study suggest that composition and distribution characteristics of carotid plaques on VH-IVUS during CAS have potential clinical significance.