Ultra-early Identification of Futile Recanalization After Reperfusion Therapy in Acute Ischemic Stroke Based on Cerebral Autoregulation Monitoring

Inclusion criteria

• Age ≥ 18
• Diagnosis of acute ischemic stroke caused by anterior circulation large vessel occlusion (intracranial internal carotid artery or M1 segment of the middle cerebral artery).
• National Institutes of Health Stroke Scale (NIHSS) score ≥ 6 at presentation.
• Pre-stroke modified Rankin Scale (mRS) score ≤ 1.
• Symptom onset ≤ 24 hours.
• For patients with symptom onset within 6 hours: ASPECTS ≥ 6; for patients with symptom onset between 6 and 24 hours: age ≤ 80 years and ASPECTS ≥ 3.
• Underwent mechanical thrombectomy and achieved successful recanalization (mTICI 2b-3).
• Patient or legally authorized representative provides written informed consent.

Exclusion criteria

• Pre-procedural baseline imaging showing significant intracranial hemorrhagic transformation, intracranial arterial dissection, large chronic cerebral infarction, or intracranial metastasis from malignant tumors.
• Any degree of stenosis, plaque, dissection, severe tortuosity, or imaging evidence of unstable/vulnerable plaque in the target-side or bilateral common carotid artery or the origin of the internal carotid artery.
• Known history of carotid sinus hypersensitivity syndrome, severe autonomic dysfunction, sick sinus syndrome, high-grade atrioventricular conduction block, or other malignant arrhythmias.
• Refractory malignant hypertensive crisis (systolic blood pressure persistently ≥ 200 mmHg despite standardized intravenous antihypertensive therapy, or hemodynamic instability with shock).
• Known severe allergy to contrast agents or anesthetic drugs, or contraindications to antiplatelet/anticoagulation therapy.
• Severe systemic active infection, multiple organ failure, or expected survival < 6 months.
• Severe hepatic or renal dysfunction (ALT/AST > 3× upper limit of normal; estimated glomerular filtration rate < 30 mL/min) or severe coagulation disorders (platelet count < 40 × 10⁹/L, APTT > 50 s, INR > 3.0).
• Blood glucose < 2.7 mmol/L or > 22.2 mmol/L.
• Heart failure with NYHA class > II, or persistent systolic blood pressure < 100 mmHg.
• Central nervous system infection or intracranial tumor.
• Unstable vital signs.
• Severe alcohol dependence or drug dependence.
• Cognitive impairment or psychiatric disorders that may affect follow-up assessments.
• Pregnant or breastfeeding women.
• Participation in another clinical drug or device study within the past 30 days.
• Local skin damage or other conditions preventing proper placement of monitoring electrodes.
• Severe agitation or other conditions that interfere with data acquisition.
• Any other condition judged by investigators to potentially affect study results.