Endovascular mechanical thrombectomy in large vessel occlusion ischemic stroke presenting with low National Institutes of Health Stroke Scale: a systematic review and meta-analysis

Abstract

INTRODUCTION: Mechanical thrombectomy has become the standard of care for management of most large vessel occlusion (LVO) strokes. When patients with LVO present with minor stroke symptomatology, no consensus on the role of mechanical thrombectomy exists. METHODS: A systematic review and meta-analysis was performed to identify studies that focused on mechanical thrombectomy, either as a standalone treatment or with intravenous tissue plasminogen activator (IV tPA), in patients with mild strokes with LVO, defined as a baseline National Institutes of Health Stroke Scale (NIHSS) score ≤5 at presentation. Data on methodology, quality criteria, and outcome measures were extracted and outcomes were compared using odds ratio (OR) as a summary statistic. RESULTS: Five studies met the selection criteria and were included. When compared to medical therapy without IV tPA, mechanical thrombectomy and medical therapy with IV tPA were associated with improved 90 day modified Rankin Scale (mRS) score. Among medical patients who were not eligible for IV tPA, those who underwent mechanical thrombectomy were more likely to experience good 90 day mRS than those who were not. There was no significant difference in functional outcome between mechanical thrombectomy and medical therapy with IV tPA, and no treatment subgroup was associated with intracranial hemorrhage or death. CONCLUSIONS: In patients with mild strokes due to LVO, mechanical thrombectomy and medical therapy with IV tPA led to better 90 day functional outcome. Mechanical thrombectomy plays an important role in the management of these patients, particularly in patients not eligible for IV tPA.