The Height and Mobility of Protruding Plaque After Carotid Artery Stenting Are Associated with Postoperative Ischemic Lesions.

Abstract

Tissue protrusion (TP) is a possible cause of cerebral infarction after carotid artery stenting (CAS). Using optical frequency domain imaging (OFDI) and angioscopy, we investigated the relationship between the morphological features of TP and postoperative new ischemic lesions on MRI-diffusion weighted imaging (DWI) after CAS. Fifty patients who underwent CAS and subsequent post-stenting intravascular evaluation using both OFDI and angioscopy were included. CAS was performed for proximal protection via the femoral artery approach, and intravascular evaluation with OFDI and angioscopy were performed after stent placement. We compared the background and post-stenting intravascular findings between patients with and without postoperative new ischemic lesions on MRI- DWI. TP was observed in 42 patients (84%), and postoperative new ischemic lesions on MRI-DWI were observed in 32 patients (64%). The frequency of TP did not differed between the two groups, but the height of TP was higher in the DWI-positive group (0.62 mm vs. 0.29 mm, p = 0.0028), and mobile TP was observed only in the DWI-positive group. The height of TP (p=0.023) was an independent predictor of new periprocedural ischemic brain lesions after CAS, and it is cut-off value was 0.55 mm on the receiver operating characteristic curve (area under the curve [AUC], 0.93). The height of TP on OFDI and mobile-TP on angioscopy after CAS were associated with postoperative new ischemic lesions on MRI-DWI. The intravascular evaluation using OFDI and angioscopy could be helpful for a detailed evaluation of TP.