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Endovascular Therapy for Acute Ischemic Stroke: A Systematic Review and Meta-analysis



      To consolidate the evidence from randomized trials for the use of endovascular therapy (ET) in patients with acute ischemic stroke.


      We searched major databases (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus) from their inception to February 12, 2013, for randomized trials evaluating the efficacy of ET compared with standard of care for acute ischemic stroke. Pooled absolute and relative risk estimates were synthesized by using a random-effects model. Heterogeneity was assessed by using Q statistic and I2 statistic. Subset analysis was performed for patients with severe stroke (National Institutes of Health Stroke Scale score ≥20). The study was conducted from January 15, 2013 to April 30, 2013.


      Of the 1252 retrieved articles, 5 randomized trials enrolling 1197 patients with acute ischemic stroke were included. Seven hundred eleven patients received ET, and 486 received intravenous (IV) tissue plasminogen activator. There was no significant improvement in any of the outcomes in patients receiving ET compared with those receiving IV thrombolysis. On subgroup analysis, ET was found to have better outcomes in patients with severe stroke (National Institutes of Health Stroke Scale score ≥20), showing a dose-response gradient and improving excellent, good, and fair outcomes by an additional 4%, 7%, and 13%, respectively, compared with IV thrombolysis.


      Overall, ET is not superior to IV thrombolysis for acute ischemic strokes (level B recommendation). However, ET showed promise and improved outcomes in patients with severe strokes, but the evidence is limited due to sample size. There is a need for further trials evaluating the role of ET in this high-risk group.

      Abbreviations and Acronyms:

      AAN (American Academy of Neurology), AIS (acute ischemic stroke), ET (endovascular therapy), IMS (Interventional Management of Stroke), IV (intravenous), mRS (modified Rankin Scale), MR-RESCUE (Mechanical Retrieval and Recanalization of Stroke Clots Using Embolectomy), NIHSS (National Institute of Health Stroke Scale), RCT (randomized controlled trial), RR (risk ratio), sICH (symptomatic intracranial hemorrhage), tPA (tissue plasminogen activator)
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