Intra-arterial Thrombolysis for Acute Ischemic Stroke With Medium Vessel Occlusion

Prior treatment

• Secondary MeVO or severe stenosis caused by endovascular therapy

Other illness

• Pre-stroke mRS ≥ 2
• Neuroimaging demonstrated intracranial hemorrhage, subarachnoid hemorrhage, or other hemorrhagic disorders
• Persistent and uncontrolled hypertension, defined as systolic blood pressure \>185 mmHg or diastolic blood pressure \>110 mmHg
• History of intracranial hemorrhage within the past 3 months, including parenchymal hemorrhage, intraventricular hemorrhage, subarachnoid hemorrhage, epidural hemorrhage, or subdural hemorrhage
• Gastrointestinal or urinary tract bleeding, or major surgery within the past 3 months
• Patients with known allergy to thrombolytic agents or their excipients
• Patients with known allergy to iodinated contrast agents or other established contraindications

Lab values

• Platelet count \<100 × 10⁹/L, known bleeding tendency or coagulation factor deficiency, or oral anticoagulant therapy with an international normalized ratio (INR) \>3.0
• Chronic dialysis or severe renal impairment, defined as a glomerular filtration rate (GFR) \<30 mL/min or serum creatinine \>220 μmol/L (2.5 mg/dL)

Other

• Non-contrast CT demonstrating a clearly hypodense lesion corresponding to the vascular territory
• Presence of arteriovenous malformations or brain tumors with mass effect
• Pregnant or current breastfeeding
• Presence of severe systemic comorbidities with a life expectancy of less than 3 months
• Deemed unsuitable for participation by the investigator for any reason

• Age \> 18 years
• Primary medium vessel occlusion (MeVO) or severe stenosis (≥70%) was detected on CTA, MRA, or DSA, involving arterial segments including M2-M3 of the middle cerebral artery (MCA), A1-A2 of the anterior cerebral artery (ACA), P1-P2 of the posterior cerebral artery (PCA), and the anterior inferior cerebellar artery (AICA), posterior inferior cerebellar artery (PICA), and superior cerebellar artery (SCA)
• The clinical symptoms were consistent with MeVO, with a NIHSS score 5 - 25, or an NIHSS score of 3-4 in the presence of disabling neurological deficits (e.g., hemianopia, aphasia, or motor dysfunction)
• Intra-arterial thrombolysis was administered within the following time windows:
  • Acute ischemic stroke within 24 hours of symptom onset or last known well, including stroke with known onset, wake-up stroke and stroke with unknown onset, with no obvious hypodensity on CT and good collateral circulation on CTA;
  • Acute ischemic stroke within 24-72 hours of onset, meeting at least one of the following imaging criteria: a.CT or MR perfusion imaging demonstrating target mismatch, defined as an ischemic core volume \<30 mL, a mismatch ratio ≥1.2, and a mismatch volume ≥10 mL.; b.MRI demonstrating DWI-FLAIR mismatch, defined as the presence of acute ischemic lesions on diffusion-weighted imaging (DWI) with no corresponding hyperintense signal on FLAIR, or with FLAIR hyperintense lesions occupying less than one-third of the DWI lesion volume.
• Signed informed consent obtained