Abstract WMP47: Cholesterol Crystals in Embolic Debris Correlate Postoperative Silent Cerebral Embolism in Carotid Artery Stenting

Abstract

Introduction: Very few studies have investigated the relationship between the histopathology of the embolic debris in embolic protection devises and postoperative cerebral embolism in carotid artery stenting (CAS). The aim of this study was to evaluate embolic debris and its association with clinical, laboratory, and neurointerventional findings in patients treated by CAS due to internal carotid stenosis. Hypothesis: Cholesterol crystals in embolic debris are associated with postoperative cerebral embolism in CAS. Methods: All embolic debris was stained with hematoxylin-eosin. Embolic debris underwent quantitative analysis to quantify three main components: red blood cells, white blood cells and fibrin, by color based segmentation. Histopathological assessment included presence of calcifications, cholesterol crystals, foamy cells, and endothelial cells. Diffusion weighted image (DWI) was evaluated 1 to 3 days after CAS, and patients were classified by presence of new lesions on DWI after CAS. Exclusion criteria were emergency CAS for stroke in evolution or crescendo transient ischemic attack. Results: From November 2015 to April 2017, 40 patients were treated in our hospital by CAS due to internal carotid artery stenosis. Exclusion criteria were fulfilled in 5 patients. 24 patients had new lesions on DWI after CAS and 11 patients did not have those. Single patient had symptomatic cerebral embolism. Patients with new lesions on DWI after CAS had higher rate of cholesterol crystal in embolic debris (80% vs 18%, p<0.01) and higher rate of patients taking strong statin on admission (71% vs 18%, P=0.02) than those without new lesions on DWI after CAS. There is no significant difference with blood levels of LDL-cholesterol [111 mg/dl (79-197) vs 108 mg/dl (62-167); p=0.85]. Main components of embolic debris were not significantly different between two groups. Conclusion: Cholesterol crystals in embolic debris and treatment history of dyslipidemia were significantly associated with post-operative high intensity lesion on DWI in CAS.