EndoVascular Treatment Beyond 24 Hours for AcutE Ischemic Stroke Caused by Anterior Circulation LArge Vessel STEnosis: A Multicenter RandomizeD Controlled Trial(EVT-BELATED)
Endovascular therapy (EVT) is currently recommended as the first-line treatment for patients with acute large vessel occlusion (LVO) in the anterior circulation within 24 hours of symptom onset. However, the therapeutic benefit of EVT beyond 24-hour window remains uncertain due to limited evidence. The EVT-BELATED trial is a multicenter, prospective, randomized, open-label, blinded end-point (PROBE) study designed to assess the safety and efficacy of EVT in patients with acute ischemic stroke (AIS) caused by anterior circulation LVO presenting beyond 24 hours after symptom onset.
• Age \> 18 years
• Acute ischemic stroke with a time window of 24 to 120 hours from symptom onset or last known well, or progressive ischemic stroke with a time from symptom onset of 24 hours to 7 days (A ≥4-point increase in NIHSS attributable to the culprit vessel territory )
• NIHSS score 5-25
• Occlusion or ≥70% stenosis of the internal carotid artery or the M1/M2 segment of the middle cerebral artery, confirmed by CTA, MRA, or DSA, and deemed to be the culprit vessel responsible for the clinical presentation of acute ischemic stroke
• Meet one of the following imaging criteria:
‣ MRI-based criteria: the infarct volume on DWI is less than one-third of the MCA territory, with evidence of DWI-FLAIR mismatch or MR perfusion showing a core infarct volume ≤30 ml, a mismatch ratio ≥1.8, and a mismatch volume ≥15 ml;
⁃ CTA-based criteria: good collateral circulation on the affected side defined ascollateral filling \>50% of the MCA territory (Tan score ≥2) and an ASPECTS score ≥6);
⁃ CTP-based criteria: ischemic core volume ≤30 ml, mismatch ratio ≥ 1.8, and mismatch volume ≥ 15mL
• Signed informed consent obtained