Inclusion Criteria:
Clinical Inclusion Criteria:
- Age >18 years;
- NIHSS ≥2;
- Onset of symptoms to baseline CT imaging time: 4.5 to 24 hours, including wake-up stroke and unwitnessed stroke; Time of onset of symptoms is defined as "last known well" (LKW);
- Pre-stroke mRS score 0-1;
- Signed informed consent from patient or their health care proxy.
Neuroimaging Inclusion Criteria:
- CTA/MRA proven intracranial artery occlusion: Intracranial Internal Carotid Artery (ICA)、M1 of Middle cerebral artery (MCA)、dominant M2 of MCA;
- ASPECTS ≥6 on non-contrast CT (NCCT) scan or DWI MRI;
- CT perfusion or MR perfusion: ischemic infarct core <70ml, mismatch ratio≥1.2, mismatch volume ≥15ml;
- Treated with MT resulting in an eTICI score 2b50-3 at end of the procedure. Patients with an eTICI score 2b50-3 on the diagnostic cerebral angiography before the onset of MT are also eligible for the study.
Exclusion Criteria:
Clinical Exclusion Criteria:
- IV thrombolysis used on admission;
- Contraindications to intravenous thrombolysis;
- Balloon angioplasty, permanent stenting and other situations during the endovascular procedure that require antiplatelet therapy or anticoagulant within the first 24h;
- IV heparin (heparinized saline allowed);
- Females who are pregnant, or those of child-bearing potential with positive urine or serum beta Human Chorionic Gonadotropin (HCG) test;
- Brain tumor (with mass effect);
- Known hereditary or acquired hemorrhagic diathesis, coagulation factor deficiency
- Known coagulopathy, INR>1.7 or use of novel anticoagulants < 48h from symptom onset
- Platelets < 50*109/L;
- Suspicion of septic emboli or endocarditis
- Renal Failure as defined by a serum creatinine > 2.5 mg/dl (or 220μmol/l) or glomerular Filtration Rate [GFR] < 30ml/min;
- Patient who requires hemodialysis or peritoneal dialysis, or who has a contraindication to angiogram for whatever reason;
- Suspicion of aortic dissection;
- Parenchymal organ surgery and biopsy were performed in the past one month;
- Any active bleeding or recent bleeding (gastrointestinal bleeding, urinary bleeding, etc.) in the past 1 month;
- History of life-threatening allergy (more than rash) to contrast medium;
- SBP >185 mmHg or DBP >110 mmHg refractory to treatment;
- Serious, advanced, terminal illness with anticipated life expectancy < 6 months;
- Participation in another randomized clinical trial that could confound the evaluation of the study;
- Other circumstances that the investigator considers inappropriate for participation or may pose a significant risk to patients (e.g. inability to understand and/or comply with study procedures and/or follow-up due to mental disorders, cognitive or mood disorders).
Specific Neuroimaging Exclusion Criteria
- Midline shift or herniation, mass effect with effacement of the ventricles
- Evidence of acute intracranial hemorrhage on CT/MRI
- Acute bilateral strokes or multiple intracranial vessel occlusions
- Isolated extracranial ICA occlusion or tandem carotid / MCA occlusion
- Dissection of occluded artery on DSA after thrombectomy