The Penumbra system for mechanical thrombectomy in endovascular acute ischemic stroke therapy

Correspondence & reprint requests to Dr. Fitzsimmons: .
Neurology (Impact Factor: 8.3). 09/2012; 79(13 Suppl 1):S135-41. DOI: 10.1212/WNL.0b013e31826958a8
Source: PubMed

ABSTRACT Efficacy of IV systemic thrombolysis is limited in patients with severe acute ischemic stroke and large-vessel occlusion. Mechanical thrombectomy has been the mainstay therapy in large-vessel occlusion. This review focuses on the Penumbra aspiration device.
Literature review.
The Penumbra prospective studies were reviewed and results are presented. The pivotal single-arm prospective trial that led to its approval by the US Food and Drug Administration enrolled 125 patients within 8 hours of symptom onset and demonstrated an 82% recanalization rate, to Thrombolysis in Myocardial Ischemia (TIMI) scores of 2 and 3. The risk of symptomatic intracranial hemorrhage was 10%, and modified Rankin Scale (mRS) score of ≤2 was 25%. In the postmarketing registry, 157 vessels were treated, with 87% achieving TIMI 2 and 3 recanalization and 41% having an mRS score of ≤2.
The Penumbra aspiration system is an effective tool to safely revascularize large-vessel occlusions in patients within 8 hours of onset of acute ischemic stroke who are either refractory to or excluded from IV thrombolytic therapy. Further prospective, randomized controlled trials will be needed to address whether this ability translates into neurologic improvement and better functional outcomes for our patients.

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