Randomized Clinical Trial of Endovascular Therapy for Acute Ischemic Stroke With Occlusion of the M2 Segment of Middle Cerebral Artery

• Endovascular therapy (Procedure): Endovascular therapy for acute ischemic stroke with occlusion of the M2 segment of the middle cerebral artery.

Primary outcomes

• Achievement of modified Rankin Scale (mRS; range, 0-6; higher scores reflect worse functional outcome) scores of 0-2 [90 days after randomization]: modified Rankin Scale (mRS) is an ordinal scale ranging from 0 (no symptoms) to 6 (death) measuring the degree of disability or dependence in everyday life.

Secondary outcomes

• Achievement of modified Rankin Scale (mRS; range, 0-6; higher scores reflect worse functional outcome) scores of 0-1 [90 days after randomization]
• modified Rankin Scale (mRS; range, 0-6; higher scores reflect worse functional outcome) shift analysis [90 days after randomization]
• National Institutes of Health Stroke Scale (NIHSS; range, 0-42; higher scores indicate more severe neurological impairment) improvement of 8 points or more [48 hours after randomization]
• Health-related quality of life assessed using the EuroQol 5-Dimension 3-Level (EQ-5D-3L; range, 0-1.0; higher scores indicating better health-related quality of life) [90 days after randomization]
• Symptomatic intracranial hemorrhage [48 hours after randomization]
• Any intracranial hemorrhage [48 hours after randomization]
• All cause death [90 days after randomization]
• Recurrence of cerebral infarction [90 days after randomization]
• Decompressive craniectomy [7 days after randomization]

Sex: All, ages: 18 Years to 84 Years

Inclusion Criteria:

1. Acute cerebral infarction
2. Aged 18-84 years
3. NIHSS score at admission ≥ 8
4. Prestroke mRS scores of 0-1 (able to carry out all usual activities)
5. Occlusion of the M2 segment of MCA on digital subtraction angiography
6. ASPECTS ≥ 8 or DWI-ASPECTS ≥ 8
7. Ineligible or failed intravenous tPA (no recanalization within 30 min after injection)
8. Randomization can be completed within 24 h from the last known well time
9. EVT can be initiated within 30 min from randomization.
10. The patient or their legally authorized representative has signed the informed consent form.

Exclusion Criteria:

1. Occlusion of the anterior temporal artery, duplicate M1, or accessory M1
2. Occlusion of multiple major intracranial arteries
3. Difficulty in endovascular access due to tortuous vascular anatomy
4. Significant mass effect with midline shift on CT (or MRI)
5. Known allergy (more severe than skin rash) to contrast agents
6. Evidence of acute intracranial hemorrhage on CT (or MRI)
7. Pregnant or potentially pregnant
8. Clinical evidence of chronic occlusion
9. High risk of hemorrhage (platelet < 40,000/ul, APTT > 50 sec or PT-INR > 3.0)
10. Participating in any other therapeutic investigational trial
11. Judgment of the investigator to be non-compliant or uncooperative during the study