The relationship between ultrasonographic plaque morphology and histopathology of embolic material captured in the protective filter during carotid artery stenting

PURPOSE: We aimed to correlate the presence or absence of embolic debris in filter-type embolic protection devices (EPD), which are frequently used during carotid artery stenting (CAS), with possible risk factors and ultrasonographic plaque features. MATERIALS AND METHODS: Eighty patients, who underwent CAS using a filter-type EPD in the period between July 2016 and March 2019, were included in our study. The modified Gray-Weale classification (mGWC) subtypes obtained in the pre-procedural ultrasonographic examinations were recorded. In addition, other patient-related risk factors considered to be related to a distal embolism were recorded. After the procedure the filters were evaluated to detect and examine embolic debris in the pathology clinic. The presence and features of embolic debris in the filters were recorded. RESULTS: In the examinations performed after CAS, embolic debris was macroscopically and microscopically detected in 22 (27%) and 34 (42.5%) of the filter-type EPDs, respectively. A significant correlation was found between the change in the mGWC category of stenotic plaques from type 5 to type 1 and the presence of embolic debris in the filter (p < 0.05). Furthermore, a significant relationship was found between stenotic segment length and the presence of embolic debris in the filter (p < 0.05). The presence of embolic debris was not statistically significantly related to predisposing risk factors for atherosclerosis (p > 0.05). CONCLUSIONS: During CAS, the likelihood of the presence of embolic debris in the EPDs increases as mGWC categories change from type 5 to type 1 and as the length of the stenotic segment increases.