Endovascular Treatment of Chronic Intracranial Artery Occlusion

This study is a multicenter, outcome-blinded, randomized controlled trial designed to evaluate the safety and efficacy of endovascular therapy combined with standard medical therapy versus standard medical therapy alone in patients with chronic intracranial artery occlusion. A total of 382 patients (191 per group) aged ≥18 years with chronic occlusion of the unilateral middle cerebral artery, basilar artery, intracranial internal carotid artery, or vertebral artery confirmed by CTA, MRA, or DSA will be enrolled and randomly assigned to the experimental group (endovascular therapy + standard medical therapy) or the control group (standard medical therapy alone). The primary endpoint is stroke or death within 30 days after enrollment, or any ischemic stroke related to the responsible artery occurring from 30 days to 12 months after enrollment. Secondary endpoints include any stroke or death within 30 days after randomization; any stroke within 12 months after the procedure; disabling stroke within 12 months after the procedure; fatal stroke within 12 months after the procedure; any death within 12 months after the procedure; mRS score at 12 months; NIHSS score at 12 months; successful reperfusion rate of endovascular therapy; and procedure-related complications.

Inclusion criteria

• Age ≥18 years
• Occlusion of the unilateral middle cerebral artery, basilar artery, intracranial internal carotid artery, or vertebral artery, as confirmed by computed tomography angiography (CTA), magnetic resonance angiography (MRA), or digital subtraction angiography (DSA)
• Modified Rankin Scale (mRS) score of 0-2
• Presence of symptoms related to the occluded vessel, as determined by the physician, with the most recent symptom onset occurring more than 4 weeks and within 6 months prior to enrolment
• The subject or their legally authorised representative has provided written informed consent for the study

Exclusion criteria

• Evidence of hemorrhage on CT or MRI
• Large hemispheric infarction involving >50% of the middle cerebral artery territory on CT or MRI
• Severe pre-stroke disability (modified Rankin Scale score ≥2) or life expectancy <12 months
• Major comorbidities that may interfere with outcome assessment and follow-up (e.g., severe heart failure, renal failure, etc.)
• Uncontrolled seizure at the time of stroke onset
• Baseline platelet count <50,000/μL
• Severe, persistent hypertension that remains uncontrolled despite active management (systolic blood pressure >220 mmHg or diastolic blood pressure >120 mmHg)
• Known inherited or acquired bleeding diathesis, coagulation factor deficiency, or recent oral anticoagulant therapy with an international normalized ratio (INR) >3
• Suspected septic emboli or suspected bacterial endocarditis
• Known allergy to iodine, heparin, or anaesthetics, or other definite contraindications to endovascular procedures
• Pregnant women
• Other severe, progressive, or terminal diseases (as judged by the investigator), or life expectancy <24 months
• Prior attempted endovascular recanalization therapy before randomization
• Current participation in other studies involving investigational drugs or devices
• Evidence of intracranial tumour on CT or MRI (except meningioma)
• Excessive tortuosity of cervical vessels on CTA/MRA that may preclude endovascular therapy