The Safety of Protected Carotid Artery Stenting in Patients with Unstable Plaque on Carotid High-Resolution MR Imaging

Abstract

Purpose:The aim of this study was to determine the safety of the carotid artery stenting (CAS) procedure, using an embolic protection device which is based on the presence of unstable plaques on carotid MR imaging in patients who presented with severe carotid artery stenosis. Materials and Methods: This prospective study assessed 102 consecutive patients who had been noted with severe carotid stenosis. These patients underwent a preprocedural carotid MR imaging, and a periprocedural diffusion-weighted imaging (DWI) after the CAS. The unstable plaque on the carotid MR imaging was defined as characterized as intraplaque hemorrhage (IPH), thin/ruptured fibrous caps, or ulcers. We analyzed the incidence of the noted periprocedural ipsilateral ischemic events on the DWI, and noted the primary outcomes within 30 days of the CAS. Results: In the study, it is noted that 50 patients (49.0%) had IPH, 84 patients (82.4%) had thin/ruptured fibrous caps, and 43 patients (42.2%) had ulcers as seen on the carotid plaque MR imaging. The IPH was more common in the symptomatic group than in the asymptomatic group (58.7% vs. 41.1%, p = 0.12). Overall, the DWI was positive after CAS in 25.5% of cases. Additionally, the combined rate of 30-day stroke, myocardial infarction, or death was recorded at 3.9%. The new periprocedural ischemic lesions on the DWI were characteristically more frequently observed in the symptomatic group (17/46, 37.0%) than in the asymptomatic group (9/56, 16.1%) (p = 0.03). There was no significant difference in the primary outcome of the CAS, based on the type of unstable plaque of IPH, thin/ruptured fibrous caps, or ulcers. Conclusion:The protected CAS appears to be safe, regardless of the noted unstable plaque findings as seen on the carotid MR imaging. In this case, because of the higher risk of periprocedural ipsilateral ischemic events, it is therefore recommended that the symptomatic patients should receive more careful treatment during the CAS placement going forward. Korea. Tel. 82-63-250-2582 Fax. 82-63-272-0481 E-mail: kwak8140@jbnu.ac.kr This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Index terms

Findings of Angiography and Carotid Vessel Wall Imaging Associated with Post-Procedural Clinical Events after Carotid Artery Stenting

“…It could predict recurrent ipsilateral stroke. 6,15,16 In our study, we analyzed imaging data considering all 3 characteristics of unstable plaques on carotid VWI and found that the percentage of patients with IPH was significantly higher than that of patients without IPH in the symptomatic group. This finding suggests that the measurement of luminal stenosis alone might not be sufficient for the source of stroke.…”

“…IPH is also strongly associated with recurrent ischemic events. It could predict recurrent ipsilateral stroke [ 6 , 15 , 16 ]. In our study, we analyzed imaging data considering all 3 characteristics of unstable plaques on carotid VWI and found that the percentage of patients with IPH was significantly higher than that of patients without IPH in the symptomatic group.…”