Randomized Clinical Trial of Endovascular Treatment for Progressive Stroke With Vertebrobasilar Artery Occlusion

Prior treatment

• Known pregnancy or lactation, or a positive pregnancy test prior to randomization.
• Current participation in any other clinical trial of drugs or medical devices, or anticipated participation in another such trial within 3 months after enrollment.

Other illness

• Any sign of intracranial hemorrhage (except microbleeds) on baseline brain imaging.
• Imaging confirms the progression of symptoms caused by intracranial hemorrhage, brain edema, or other clear causes.
• Refractory hypertension not controlled by medication, defined as systolic blood pressure \>185 mmHg or diastolic blood pressure \>110 mmHg.
• Known dementia or psychiatric disease precluding completion of neurological assessment and follow-up.
• Life expectancy \<1 year, including patients with malignancy or advanced cardiopulmonary disease.
• Acute ischemic stroke within 48 hours after cardiovascular or cerebrovascular interventional treatment or major surgery; patients presenting \>48 hours after such procedures were eligible.
• Recent (within 1 month) gastrointestinal or genitourinary bleeding, acute myocardial infarction, or traumatic brain injury.
• Any other condition deemed by the site investigator to make the patient unsuitable for participation.

Lab values

• Known hereditary or acquired bleeding diathesis, coagulation factor deficiency, current use of oral anticoagulants with an INR \>1.5, or active bleeding.
• Blood glucose \<2.8 or \>22.2 mmol/L; platelet count \<100 × 10⁹/L; estimated glomerular filtration rate (eGFR) \<30 mL/min/1.73 m² or serum creatinine ≥177 μmol/L (2.0 mg/dL).

Other

• Extensive cerebellar infarction with significant mass effect or bilateral thalamic infarction on baseline neuroimaging.
• Presence of untreated intracranial aneurysm, intracranial tumor (except small meningioma and aneurysms \<3 mm in diameter), or intracranial arteriovenous malformation.
• Known or highly suspected chronic responsible artery occlusion.
• Presence of severe stenosis in the extracranial or intracranial segment of the responsible artery, arterial dissection, or excessive vascular tortuosity that may prevent successful delivery or navigation of endovascular devices.
• Known contraindication to contrast medium (except mild rash).
• Multivessel severe stenosis or occlusion confirmed by CTA, MRA, or DSA.
• Known or suspected central nervous system vasculitis.

• Age ≥18 years.
• Acute ischemic stroke, with a National Institutes of Health Stroke Scale (NIHSS) score of \<10 at initial symptom onset, and no prior endovascular treatment.
• Stroke progression occurring from 24 hours to 14 days after initial symptom onset, defined as an NIHSS score of ≥10 with an increase of ≥4 points from baseline.
• Acute basilar artery occlusion or dominant vertebral artery occlusion with contralateral occlusion or hypoplasia, confirmed by CTA, MRA or DSA.
• Posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS) of ≥6 and Pons-Midbrain Index (PMI) of ≤3 on CT or diffusion-weighted imaging (DWI).
• Randomization within 24 hours of stroke progression.
• Pre-stroke mRS score of 0-2.
• Provision of signed informed consent by the patient or their legal representative.