Key Points
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Five randomized trials of endovascular stroke therapy published in 2015 provided strong evidence in support of using stent retriever thrombectomy for anterior circulation strokes when initiated within 6 h of stroke onset
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Various imaging approaches are used to select patients to receive endovascular interventions; the most effective imaging modality remains to be determined
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The status of thrombectomy for stroke has now changed from 'experimental' to 'recommended' therapy
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Questions remain about the management of posterior circulation strokes, the time window of effective endovascular treatment beyond 6 h of stroke onset, and the choice of anaesthesia for endovascular procedures
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Future trials are likely to compare thrombectomy devices to optimize the procedure
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Health-care systems will need to adapt to using endovascular therapies, and access to the treatment in remote areas and developing countries will pose a challenge
Abstract
Five trials that investigated the efficacy of modern endovascular therapies for stroke — MR CLEAN, ESCAPE, SWIFT PRIME, EXTEND IA and REVASCAT — have been published within the past year, changing the landscape of acute stroke management. The trials used a variety of imaging modalities and combinations of treatment approaches, including the mandatory use of intravenous thrombolysis before the initiation of endovascular therapy. All five trials provided strong evidence to support the use of thrombectomy that is initiated within 6 h of stroke onset, prompting worldwide changes in the guidelines for management of acute stroke by endovascular treatment. The benefits of endovascular therapy were observed irrespective of a patient's age, their NIH Stroke Scale score, or whether they received intravenous thrombolysis. In this article, we review the main findings of these recent trials, focusing on key aspects of their designs, and discuss their impact on the future management of patients with acute stroke that results from large-vessel occlusion. We discuss the values of noncontrast CT ASPECTS, perfusion imaging and angiography for selecting patients to receive endovascular interventions. We also consider the role of thrombectomy beyond 6 h after stroke onset, and in patients with posterior circulation strokes.
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M.M. researched data for the article. All authors made substantial contributions to discussion of the content of the article, wrote the article, and reviewed and/or edited the manuscript before submission.
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E.I.L. was a principal investigator of the Covidien US SWIFT PRIME trial, has had shareholder or ownership interests in Intratech Medical, CardinalHealth (formerly AccessClosure) and Blockade Medical, and has received compensation from Abbott for carotid stenting training for physicians. M.M. and H.R. declare no competing interests.
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Mokin, M., Rojas, H. & Levy, E. Randomized trials of endovascular therapy for stroke — impact on stroke care. Nat Rev Neurol 12, 86–94 (2016). https://doi.org/10.1038/nrneurol.2015.240
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DOI: https://doi.org/10.1038/nrneurol.2015.240
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