Evaluate Endovascular Treatment of Large Ischemic Stroke With Substantial Penumbra.

Overview

Large cerebral infarctions are frequent and associated with a poor outcome. Previous cohort studies results suggest that patients with an acute ischemic stroke with large core and substantial penumbra on perfusion imaging benefit from EVT while those with no salvageable ischemic tissue did not. The Investigator aim to demonstrate in a randomized controlled trials (RCT) that EVT (Endo Vascular Treatment) in addition to BMT (Best Medical Treatment) increases the rate of functional recovery (mRS 0-2) at 3 months in patients with a LVO-related AIS with a large core and substantial penumbra evolving for less than 24hrs

The reperfusion of salvageable ischemic tissue (penumbra) to improve functional recovery is the aim of the endovascular treatment (EVT) of acute ischemic stroke (AIS) complicating large cerebral vessel occlusion (LVO). Downstream of an LVO, imaging profiles are highly variable ranging from a large completed infarction within 2 hrs to a small core and a large mismatch at 24 hrs after onset . A large core is typically associated with a poor prognosis and was a common exclusion criterion from the RCTs that demonstrated the efficacy of EVT for LVO related AIS . However the investigator recently reported that AIS with a large core 1- represent 20% of the LVO-related AIS scanned within 6 hours after onset 2- Up to 50% had a MM on perfusion imaging and 3- EVT increases the rate of functional recovery in patients with a large core over BMT only in the subgroup of patients with a MM (Mismatch) on baseline imaging . One hundred and eighty patients experiencing an LVO-related AIS within 24 hours after last known well, with a documented large core (\>70mL) and a MM on baseline imaging will be randomized (1:1) to undergo EVT+BMT vs. BMT in a multicenter, randomized, controlled, open-label, in parallel groups with blinded endpoint evaluation (PROBE design) superiority trial. Study participants will be followed up for 6 months. Participants will be treated and managed in acute stroke units by certified stroke neurologists and neurointerventionists according to the current recommendations . Neurological deficit will be assessed using the NIH Stroke Scale (NIHSS) by certified investigators.