Stent retriever versus direct aspiration thrombectomy for acute large vessel occlusion: A meta-analysis including 17,556 patients, from MR CLEAN to present

Abstract

ObjectiveStent retriever (SR) and direct aspiration (DA) mechanical thrombectomy (MT) improve clinical outcomes for stroke secondary to large vessel occlusion. The purpose is to perform an updated meta-analysis comparing the two techniques. MethodsPubMed database was searched for studies between January 1, 2015, and July 5th, 2021 with mechanical thrombectomy to treat acute ischemic stroke. ResultsWe identified 136 studies including 17,556 patients, with 11,258 (64.1%) patients treated by SR or a combined approach and 6298 (35.9%) patients with DA. The DA group had less posterior cerebral artery strokes, was significantly older, and had lower National Institutes of Health Stroke Scale scores (p = .05,.02,.04) There was no difference between groups in percentage of middle cerebral artery or internal carotid artery occlusions or intravenous tissue plasminogen activator administered (p = .62,.19,.06). A regression model showed no difference between SR and DA in mortality, symptomatic intracranial hemorrhage, and disability (mRS > 2) at 90 days (p = .13,.75,.84). Successful reperfusion (mTICI 2b/3 rates) were higher in the DA group (DA 87.6% vs SR 82.3%, p < .01), but after accounting for covariates was not significant (p = .17). ConclusionOur updated meta-analysis shows that DA has similar safety, reperfusion and 90-day clinical outcomes compared to SR. These results should serve to increase confidence in DA thrombectomy for acute ischemic stroke secondary to LVO.