Immediate Angioplasty For Acute Ischemic Stroke With Severe Intracranial Atherosclerotic Stenosis

A multicenter, prospective, open-label, blinded endpoint, randomized controlled trial that aims to evaluate the effect of immediate angioplasty (with or without stenting) for acute ischemic stroke (AIS) with severe intracranial atherosclerotic stenosis (ICAS) in improving the 90-day functional outcome.

This study is a multicenter, prospective, open-label, blinded endpoint, randomized controlled trial designed to evaluate the effect of immediate angioplasty (with or without stenting) for AIS with severe ICAS. The primary outcome is the proportion of patients with a 90-day modified Rankin scale (mRS) of 0-2.

Study intervention: (1) Participants in the experimental group will undergo immediate angioplasty (with or without stenting), and will receive the best medical treatment (BMM) after the procedure. (2) Participants in the control group will receive BMM alone.

This study is anticipated to enroll 418 participants, with 209 participants in each group (1:1 ratio).

Eligibility Criteria:
Inclusion Criteria:

1. Aged 18 years or older.
2. Diagnosed with AIS and baseline NIHSS ≥6.
3. Pre-stroke mRS ≤2, or mRS \>2 but not related to neurological disease (e.g., amputation, blindness).
4. Time from symptom onset to randomization within 24 hours; the onset time refers to "Last Known Well" (LKW).
5. NCCT/DWI-MRI ASPECTS ≥6.
6. CTA, MRA, or DSA confirmed severe ICAS (70-99%) of the intracranial segment of the internal carotid artery, or M1 or M2 segment of the middle cerebral artery, and is presumed to be responsible for the stroke.
7. Signed informed consent.

Exclusion Criteria:

1. Normal diameter of the culprit vessel \<2.0 mm.
2. Hemorrhagic stroke within the past 90 days.
3. Stroke is caused by cerebral vasculitis, arterial inflammatory stenosis, vasospasm, dissection, perforating arteriopathy, and internal capsule warning syndrome.
4. Severe calcification at the site of stenosis, where target residual stenosis \<30% could not be achieved.
5. Stroke caused by cardioembolic origin, but those with only atrial fibrillation but no clear evidence of cardiac thrombosis could still be included in the study.
6. Coagulation disorder with INR\>1.7, use of new oral anticoagulants within the last 48 hours from screening, or use of low molecular weight heparin within the last 24 hours from screening.
7. Known genetic or acquired bleeding disposition with anticoagulation factor deficiency.
8. Platelet count \<50×10\^9/L.
9. Intracranial hemorrhage confirmed by CT or MRI.
10. Women who are pregnant or breastfeeding.
11. Participation in other clinical trials.
12. Known severe renal insufficiency with glomerular filtration rate \<30 ml/min or blood creatinine \>220 μmol/L (2.5 mg/dl).
13. Severe allergy to contrast (non-mild rash allergy) or absolute contraindication to iodine contrast.
14. Aortic dissection.
15. Intracranial tumors or arteriovenous malformations.
16. Previous parenchymal organ surgery or biopsy in the last 1 month.
17. Any active bleeding or recent bleeding (gastrointestinal, urinary tract bleeding, etc.) in the last 1 month.
18. SBP\>185 mmHg or DBP\>110 mmHg refractory to treatment.
19. Anticipated life expectancy \<3 months (e.g., malignancy, severe cardiopulmonary disease, etc.).
20. Any condition that, in the judgment of the investigator, makes the patient unsuitable for this study or where this study may impose a significant risk to the patient (e.g., inability to understand and/or comply with study procedures and/or follow-up due to psychiatric disorders, cognitive or emotional impairment).