J Clin Neurol.  2018 Jul;14(3):407-412. 10.3988/jcn.2018.14.3.407.

Mechanical Thrombectomy in Strokes with Large-Vessel Occlusion Beyond 6 Hours: A Pooled Analysis of Randomized Trials

• Vidale S
• Longoni M
• Valvassori L
• Agostoni E

• KMID: 2415060
• DOI: http://doi.org/10.3988/jcn.2018.14.3.407

Abstract

BACKGROUND AND PURPOSE
Mechanical thrombectomy with or without intravenous thrombolysis is indicated in the acute treatment of ischemic strokes caused by an emergent large-vessel occlusion (ELVO) within 6 hours from symptom onset. However, a significant proportion of patients are referred to comprehensive stroke centers beyond this therapeutic time window. This study performed a pooled analysis of data from trials in which mechanical thrombectomy was performed beyond 6 hours from symptom onset.
METHODS
We searched for randomized controlled trials that compared mechanical thrombectomy with the best medical treatment beyond 6 hours for ischemic strokes due to ELVO and reported on between 1990 and April 2018. The intervention group comprised patients treated with mechanical thrombectomy. Statistical analysis was conducted while pooling data and analyzing fixed- or random-effects models as appropriate.
RESULTS
Four trials involving 518 stroke patients met the eligibility criteria. There were 267 strokes treated with mechanical thrombectomy, with a median time of 10.8 hours between when the patient was last known to be well to randomization. We observed a significant difference between groups concerning the rate of functional independence at 90 days from stroke, with an absolute difference of 27.5% (odds ratio=3.33, 95% CI=1.81-6.12, p < 0.001) and good recanalization (odds ratio=13.17, 95% CI=4.17-41.60, p < 0.001) favoring the intervention group.
CONCLUSIONS
This meta-analysis confirms the efficacy of mechanical thrombectomy in selected ischemic stroke patients beyond 6 hours from symptom onset. The selection is mainly based on the limited core infarct detected by emergent assessment using neuroimaging techniques.

Keyword

stroke; large-vessel occlusion; mechanical thrombectomy; meta-analysis; therapeutic time window; 6 hours

MeSH Terms

Humans
Neuroimaging
Random Allocation
Stroke*
Thrombectomy*

Figure

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  Fig. 1 PRISMA flow diagram. Adapted from Moher et al.9 Plos Med 2009;6:e1000097.

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  Fig. 2 Forest plot of the primary endpoint.

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  Fig. 3 Forest plots of the secondary endpoints: (A) good recanalization, (B) death at 90 days after stroke, and (C) symptomatic intracranial hemorrhage.

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