Endovascular Thrombectomy for Low ASPECTS Large Vessel Occlusion Ischemic Stroke: A Systematic Review and Meta-Analysis

Abstract

Background: The current American Heart Association guidelines for acute ischemic stroke reserve Grade 1A recommendation for the use of endovascular thrombectomy (EVT) for patients with an Alberta Stroke Program Early Computed Tomography Score (ASPECTS) of ≥6. Objective: We aim to determine the safety and efficacy of EVT for large vessel occlusion ischemic stroke patients with low ASPECTS (5 or less). Methods: Medline, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov were searched for studies appraising the outcomes of EVT for low ASPECTS ischemic stroke. A meta-analysis of proportions compared the clinical outcomes of patients undergoing EVT and those receiving best medical therapy only. Results: Nine studies (1,196 patients) were included. There was a trend (p = 0.11) toward a higher rate of symptomatic intracranial hemorrhage (sICH) in the EVT group (9.2%; 95% CI 6.1–13.6; I2 53.37%) compared to the medical group (5.5%; 95% CI 3.7–8.1; I2 0%). There was no difference (p = 0.41) in the pooled 90-day mortality of EVT patients (30.7%; 95% CI 21.7–41.5; I2 84.23%) and medical patients (36.6%; 95% CI 26.4–48.1; I2 76.2%). EVT patients had better (p = 0.001) 90-day outcomes, with 27.7% (95% CI 21.8–34.5; I2 62.08%) of patients attaining a modified Rankin Scale of 0–2 compared to only 3.7% (95% CI 2.3–5.9; I2 87.21%) in the medical group. Conclusions: This meta-analysis demonstrates a trend in higher sICH among low ASPECTS patients undergoing EVT. Despite this, a significant proportion of this subset of patients still achieved good functional outcomes at 90 days. Randomized trials are necessary to substantiate this result as significant bias is inherent in the observational studies included in this review.

Association of Ischemic Core Imaging Biomarkers With Post-Thrombectomy Clinical Outcomes in the MR CLEAN Registry

“…Most probably, the different results between this analysis and our study can be explained by the (much) larger sample size (201 vs. 3279 patients) in their analysis. The benefit of EVT in patients with low ASPECTS has been extensively explored in previous studies ( 21 , 22 ). In a subgroup analysis of the MR CLEAN trial, ASPECTS 5-7 was associated with functional outcome (relative to ASPECTS 8-10 and ASPECTS 0-4), however no significant modification of treatment effect by ASPECTS was found ( 21 ).…”

Cerebral blood volume index may be a predictor of independent outcome of thrombectomy in stroke patients with low ASPECTS

“…However, for those patients with ASPECTS ＜6, the efficacy and safety of EVT is not conclusive. One meta-analysis demonstrated a significant proportion of this subset of patients still achieved good functional outcomes at 90 days and a trend in higher symptomatic intracranial hemorrhage (sICH) among low ASPECTS patients undergoing EVT [4]. More recently, one randomized controlled trial (RCT) from Japan showed that patients with large cerebral infarction had better functional outcomes with EVT than with medical care alone but had more intracranial hemorrhages [5].…”

The Benefit of Thrombectomy in Patients With Low ASPECTS Is a Matter of Shades of Gray—What Current Trials May Have Missed

“…Randomized clinical trial data supporting the benefit of endovascular treatment in acute ischemic stroke patients with a large early infarction are not yet available (1). Few retrospective studies exist that suggest a potential positive treatment effect on the functional outcome, as well as procedural safety (2)(3)(4)(5)(6)(7).…”