Abstract WMP4: Predictors of Functional Recovery After Thrombectomy in Posterior Circulation Stroke - Insights From the STAR Collaboration

Abstract

Introduction: Endovascular thrombectomy (ET) for treating acute stroke in the real-world has expanded beyond the selection criteria used in major trials, and currently includes posterior circulation strokes. Posterior circulation stroke is believed to have worse outcomes than anterior circulation stroke, and its outcomes following ET are still being studied. We explored the major determinants of functional recovery after ET for posterior circulation stroke in a large cohort of patients from the Stroke Thrombectomy and Aneurysm Registry (STAR). Methods: STAR includes patients undergoing ET for acute ischemic stroke at 12 comprehensive stroke centers in the US and globally. Data on patient demographics, technical and clinical outcomes was reviewed retrospectively from patient charts and procedure notes. Primary outcomes was the modified Ranking Score (mRS) at 90 days dichotomized into favorable (mRS 0-2) and poor outcome (mRS 3-6). Results: A total of 3850 patients were reviewed, of which 345 patients (mean age 60±14) were treated for posterior circulation stroke with predominantly basilar artery occlusion (80%). Patients were treated using aspiration thrombectomy (ADAPT, 39%), stent retriever thrombectomy (31%), combined approach (19%) or intracranial stenting (7%). The overall rate of favorable outcome was 33%. Patients with diabetes, high NIHSS on admission, and proximal occlusions had significantly higher odds of poor functional outcomes on multivariate analysis (p<0.05). Compared to ADAPT thrombectomy, significantly higher odds for poor outcomes were observed with the use of stent retriever (aOR=0.84, p<0.01) or primary combined approach (aOR=2.85, p=0.05). The advantage of ADAPT on functional recovery compared to stent retrievers persisted when regression models were limited to patients with successful recanalization, or with basilar artery occlusions. No differences in complication and hemorrhage rates were observed. Conclusions: Despite similar rates of functional recovery after ET for anterior circulation stroke between stent retriever and ADAPT, our analysis demonstrates that in posterior circulation stroke, ADAPT may lead to better functional outcomes compared to stent retriever without differences in safety profiles.