Abstract 211: Comparing Early and Late Window 3mm Trevo Stent Retriever Performance in Medium Vessel Occlusion Thrombectomy

Abstract

Introduction Endovascular thrombectomy has been shown to be beneficial for select patients with medium vessel occlusion ischemic strokes. Newer mechanical thrombectomy devices have designs to facilitate navigation of the medium and distal cerebrovasculature. In this single‐center study, we aim to compare the performance of 3mm Trevo NXT stent retrievers (Stryker, Kalamazoo, MI) for medium vessel occlusion mechanical thrombectomy for patients treated within either the early (6 hour) treatment window. Methods A retrospective review was conducted of acute ischemic stroke patients with medium vessel occlusions (i.e., M2‐M4, ACA, and PCA) who underwent thrombectomy over 5 years (2018‐2022) at a single comprehensive stroke center. Classification into early or late window was defined as time from last known well to groin puncture less than 6 hours or greater than 6 hours, respectively. Primary efficacy outcome included successful recanalization (modified thrombolysis in cerebral infarction [mTICI]>=2B) using 3mm Trevo NXT on either first pass or rescue pass (i.e., after initial pass failure with another device). Primary safety outcome is rate of complications associated with the stent retriever. Primary clinical outcome was National Institutes of Health Stroke Scale (NIHSS) shift between admission and discharge. Results Of 81 patients with medium vessel occlusion ischemic strokes, 38 patients (44.7% female, median age of 73.5 years [IQR 66‐82], median initial NIHSS 13 [IQR 8‐23]) underwent thrombectomy with 3mm Trevo NXT. Stent retriever‐assisted aspiration (versus stent retriever only) was performed in 31/38 (81.6%) patients. Successful recanalization with stent retriever was achieved in 28/38 (73.7%) of patients. There was no significant difference in rate of recanalization between early and late window thrombectomy (16/22 [72.7%] early window vs. 12/16 [75%] late window, p=0.8752). The lack of significant difference in recanalization rate was consistent with stent retriever use during first pass (11/14 [78.6%] early window vs. 9/10 [90%] late window, p=0.6146) and as rescue (5/8 [62.5%] early window vs. 3/6 [50%] late window, p=0.6400). There was no significant difference in the rate of stent retriever complications between early and late windows (1/16 [6.3%] early vs. 0/22 [0%] late, p=0.4211). There was no significant difference in median NIHSS shift from admission to discharge ( ‐6 [IQR ‐16 ‐ 9] early window vs. ‐3 [IQR ‐5 ‐ 4] late window, p=0.3666). Conclusion In both early and late window medium vessel occlusion thrombectomy, the 3mm Trevo NXT as first line and rescue intervention performs comparably and adequately. Future multicenter studies will further characterize novel stent retriever performance in medium vessel occlusion thrombectomies.