The Efficacy and Safety of Endovascular Therapy for Acute Ischemic Stroke Due to Large Core Infarction

Inclusion Criteria: 1. The age ranged from 18 to 80 years 2. Acute ischemic stroke in posterior circulation, the time from stroke onset (or finally found normal) to randomization was within 24 hours 3. Acute basilar artery occlusion confirmed by CTA,MRA,or DSA 4. Posterior circulation large core infarction:NCCT or DWI showed pc-ASPECTS≤5, or Pons-Midbrain Index (PMI)≥3 5. NIHSS score ≥10 before randomization 6. Pre-stroke mRS of 0-2 7. Each patient or their legal representative must provide written informed consent before enrolment Exclusion Criteria: 1. Any sign of intracranial hemorrhage (except microbleeds) on brain imaging prior to randomization 2. Complete cerebellar infarct with significant mass effect, or bilateral thalamic infarction as evidenced by baseline neuroimaging 3. Known or highly suspected chronic occlusion of basilar artery 4. History of contraindication for contrast medium (except mild rash) 5. Current pregnant or breast-feeding 6. Refractory hypertension (defined as systolic blood pressure\>220 mmHg or diastolic blood pressure\>110 mmHg) that cannot be controlled by drug treatment; 7. Known to have dementia or psychiatric disease unable to complete neurological assessment and follow-up 8. It is known that patients with dementia or mental illness cannot complete neurological function assessment and follow-up 9. Patients whose life expectancy is less than 1 year (such as patients with malignant tumor, advanced cardiopulmonary disease, etc.) 10. Enrolled in another drug or device trial or expected to participate in another drug or device treatment trial within the following 3 months 11. Any other condition (in the opinion of the site investigator) that inappropriate to participate this study 12. CTA/MRA/DSA confirmed occlusion of anterior and posterior circulation 13. Central nervous system vasculitis has been diagnosed or clinically suspected 14. Known hereditary or acquired bleeding tendency, lack of coagulation factors, or oral anticoagulants with INR\>1.7 15. Blood glucose\<2.7 or\>22.2 mmol/L; Platelet count\<50×109/L, glomerular filtration rate\<30ml/min or serum creatinine ≥ 3 mg/dl 16. Acute cerebral infarction occurred within 48 hours after cardio cerebral vascular intervention or major surgery (patients over 48 hours can be included in the group)