The purpose of this study is to evaluate whether endovascular thrombectomy (EVT) combined with best medical management (BMM) leads to better functional outcomes than BMM alone in patients with acute basilar artery occlusion with posterior circulation large infarct.

This study is a multicenter, prospective, cohort study that prospectively enrolled consecutive patients with acute basilar artery occlusion and large core infarction in the posterior circulation, confirmed by imaging (CTA/MRA/DSA). Written informed consent was obtained from all participants or their legal representatives prior to enrollment. Patients were divided into the best medical management (BMM) group and the endovascular thrombectomy (EVT) group according to the treatment they received. This study adhered to the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines.

Inclusion Criteria:

1. Age 18-80 years old;
2. Acute ischemic stroke in the posterior circulation, the onset of stroke (or last well known) to the enrollment time within 24 hours;
3. CTA/MRA/DSA confirmed acute basilar artery occlusion;
4. Posterior circulation large infarct: NCCT or DWI showed pc-ASPECTS ≤ 5 points, or pontine midbrain index (PMI) ≥ 3 points;
5. NIHSS score ≥10 points after the onset of the stroke and before enrollment;
6. Able to live independently before the onset of the disease (mRS score ≤2 points);
7. The subject or legal representative is able to sign the informed consent form.

Exclusion Criteria:

1. Intracranial hemorrhage (except microhemorrhage) on CT/MRI ;
2. CT/MRI revealed large infarction in the cerebellar hemisphere, with significant mass effect causing compression of the fourth ventricle or brainstem;
3. CT or MRI showed bilateral complete thalamic infarction;
4. Occlusion of anterior and posterior circulation arteries confirmed by CTA/MRA/DSA;
5. The presence of intracranial tumors (except for small meningiomas and cerebral aneurysms with a diameter of <3mm);
6. Patients with known or highly suspected chronic basilar artery occlusion.;
7. Known severe allergy to contrast agents (except for mild rash);
8. Refractory hypertension (defined as systolic blood pressure > 185 mmHg or diastolic blood pressure >110 mmHg) that cannot be controlled by drug therapy;
9. Known pregnant or lactating females, or positive pregnancy test before enrollment;
10. Acute cerebral infarction within 48 hours after cardiovascular and cerebrovascular intervention or major surgery (patients more than 48 hours can be enrolled).

Acute basilar artery occlusion with large infarct