Carotid Plaque Surface Irregularity Predicts Cerebral Embolism during Carotid Artery Stenting

Background and Purpose: Carotid artery stenting (CAS) is associated with the risk of periprocedural embolic events. The procedural risk may vary with plaque characteristics. We aimed at determining the impact of carotid plaque surface irregularity on the risk of cerebral embolism during CAS. Methods: Solid microembolic signals (MES) during CAS for symptomatic carotid stenosis were assessed by means of dual-frequency transcranial Doppler ultrasound. Study endpoint was the number of solid MES during CAS in 12 patients with irregular carotid stenosis compared to 12 matched patients with smooth carotid stenosis. Results: A total of 438 solid MES were detected. The cumulative number of solid MES was 329 in patients with irregular plaques and 109 in those with smooth plaques. The proportion of subjects in whom solid MES were detected was higher in the irregular plaque group (11/12) than in the smooth plaque group (5/12) (p = 0.030). The numbers of solid MES per CAS procedure and per hour of CAS procedure were both higher in patients with irregular plaques than in those with smooth plaques (p = 0.008 and 0.015, respectively). Conclusions: Carotid plaque surface irregularity predicts solid cerebral embolism during stenting of symptomatic carotid artery stenosis.