Predictive values of carotid high-resolution magnetic resonance imaging for large embolus shedding in carotid artery stenting.

Background: Embolus shedding is one of the important complications in carotid artery stenting (CAS). Carotid high-resolution magnetic resonance imaging (HR-MRI) is often used to directly reflect important biological characteristics, such as plaque size and composition, as well as the structure of the carotid artery wall. The aim of this study was to investigate the predictive values of carotid HR-MRI for large embolus shedding in CAS.

Methods: In total, 195 patients with carotid stenosis were enrolled. Preoperative carotid HR-MRI was performed to define the nature of the carotid plaques. CAS was performed in all patients, and intraoperative embolic protection devices were used to collect the shed emboli. According to the diameter and number of shed emboli, the patients were divided into the small-embolus group (group X) and largeembolus group (group Y). Logistic regression analysis was used to analyze the risk factors of large embolus shedding.

Results: Group Y included 58 patients, and group X included 137 patients. Age, stenosis length, smoking, and ≥3 transient cerebral ischemic attacks were risk factors for large embolusshedding. Two cases of shed large emboli developed from stable plaques, and 56 cases of large emboli developed from vulnerable plaques. When vulnerable plaques were associated with more risk factors, the incidences of large embolus shedding in cases with vulnerable plaques combined with 0, 1, 2, 3, and 4 risk factors were 44 % (4/9), 68.1% (15/22), 72.2% (13/18), 76.5% (13/17), and 84.6% (11/13), respectively.

Discussion: Carotid HR-MRI can predict the incidence of large embolus shedding in CAS.