Endovascular Thrombectomy With and Without Intravenous Thrombolysis in Extended Time Window

Inclusion Criteria:

1. Patient/Legally Authorized Representative has signed the Informed Consent form
2. Age ≥ 18
3. Clinical signs consistent with an acute ischemic stroke
4. Neurological deficit with a NIHSS of ≥ 6 (deficits judged to be clearly disabling atpresentation)
5. Patient is eligible for intravenous thrombolysis
6. Patient is eligible for endovascular treatment
7. Randomization no later than 8 hours 45 minutes after stroke symptom onset andinitiation of IV t-PA must be started within 9 hours of stroke symptoms onset (forstroke with unknown time of onset, the midpoint of the time last known to be well andsymptom recognition time)
8. ICA or MCA-M1 occlusion (carotid occlusions can be cervical or intracranial; with orwithout tandem MCA lesions) by MRA or CTA (including the reconstructed CTA derivedfrom CTP). And target Mismatch Profile on CT perfusion or MRI (ischemic core volume is < 70 ml, mismatch ratio is >/= 1.8 and mismatch volume is >/= 15 ml)
9. Core-infarct volume of Alberta Stroke Program Early CT Score (ASPECTS) ≥ 6 based onbaseline CT or MR imaging (MRI) (a region has to have diffusion abnormality in 20% ormore of its volume to be considered MR-ASPECTS positive)

Exclusion Criteria:

1. Acute intracranial hemorrhage
2. Any contraindication for IV t-PA
3. Pre-treatment with IV t-PA
4. Pregnancy or lactating women. A negative pregnancy test before randomization isrequired for all women with child-bearing potential.
5. Known (serious) sensitivity to radiographic contrast agents, nickel, titanium metals,or their alloys
6. Known current participation in a clinical trial (investigational drug or medicaldevice)
7. Renal insufficiency as defined by a serum creatinine > 2.0 mg/dl (or 176.8 µmol/l) orglomerular filtration rate (GFR) < 30 mL/min or requirement for hemodialysis orperitoneal dialysis
8. Severe comorbid condition with life expectancy less than 90 days at baseline
9. Known advanced dementia or significant pre-stroke disability (mRS score of ≥2)
10. Foreseeable difficulties in follow-up due to geographic reasons (e.g. patients livingabroad)
11. Comorbid disease or condition that would confound the neurological and functionalevaluations or compromise survival or ability to complete follow-up assessments
12. Subject currently uses or has a recent history of illicit drug(s) or abuses alcohol (defined as regular or daily consumption of more than four alcoholic drinks per day).
13. Known history of arterial tortuosity, pre-existing stent, other arterial diseaseand/or known disease at the femoral access site that would prevent the device fromreaching the target vessel and/or preclude safe recovery after MT
14. Radiological confirmed evidence of mass effect or intracranial tumor (except smallmeningioma)
15. Radiological confirmed evidence of cerebral vasculitis
16. CTA or MRA evidence of carotid artery dissection
17. Evidence of additional distal intracranial vessel occlusion in another territory (i.e.A2 segment of anterior cerebral artery or M3, M4 segment of MCA) on initial NCCT/MRIor CTA/MRA