Endovascular Therapy Versus Best Medical Treatment for Acute Large Vessel Occlusion Stroke With Low NIHSS

Patients presenting with mild symptoms of acute ischemic stroke are common and account for approximately half of all acute ischemic stroke. About 30% of patients with minor stroke have a 90-day functional disability. Radiologically proven a large vessel occlusion (LVO) in patients with minor stroke is a well-established predictor of poor outcomes, while the poor outcomes following best medical management in patients with minor stroke with the underlying presence of a LVO are mainly driven by the occurrence of early neurological deterioration (END).

Considering the well-known strong association between lack of arterial recanalization and END, endovascular therapy (EVT) appears as an attractive option to improve functional outcomes for LVO-related patients with stroke with mild symptoms. Whether EVT is safe and effective in patients with mild stroke with an LVO is currently debated, since these patients were typically excluded from the pivotal EVT trials.

The current study aimed to further test the hypothesis that endovascular therapy would be superior to medical management with respect to functional recovery among low NIHSS patients caused by acute large-vessel occlusion in the anterior circulation.


Eligibility Criteria:
Inclusion Criteria:

* 1. Age ≥18 years
* 2. Randomization can be finished within 24 hours from stroke onset (stroke onset time is defined as last known well time)
* 3.NIHSS score 2-5 at the time of randomization, but must include one of the following: any consciousness disorder (≥1 on NIHSS Question #1a); partial facial paralysis (≥1 on NIHSS Question #4); any weakness limiting sustained effort against gravity (≥1 on NIHSS Question #6 or #7); severe aphasia (≥1 on NIHSS Question #9), or visual or sensory extinction (≥1 on NIHSS Question #11).
* 4.CTA or MRA proven occlusion of the Internal Carotid Artery (ICA) terminal or M1/M2 segment of Middle Cerebral Artery
* 5.CTP/MRP Imaging shows the volume of Tmax\>6s ≥ 50ml.
* 6. Informed consent signed

Exclusion Criteria:

* 1. Pre-stroke mRS score ≥1
* 2. Vascular occlusion caused by special causes is not suitable for endovascular treatment, such as Moyamoya disease, arteritis, radiation vascular disease, or fibromuscular development defective, and combined intracranial tumors, aneurysms, or intracranial arteriovenous malformations;
* 3. Severe comorbidities or unstable conditions, such as severe heart failure, pulmonary or renal failure (serum creatinine\>2.8mg/dL or 250 µ mol/L or glomerular filtration rate \<30ml/min), severe liver dysfunction and malignant tumors;
* 4. Any active bleeding or recent bleeding (gastrointestinal bleeding, urinary bleeding, etc.) in the past six months
* 5. Baseline platelet count \<100×109 /L;
* 6. Refractory abnormal blood sugar that is difficult to control by medication (50mg/dL or 2.78mmol/L or 400mg/dL or 22.2mmol/L）;
* 7. Angiography shows a tortuous vascular pathway, making it difficult for the experimental equipment to reach the target position or retrieve it;
* 8. Known severe allergy for contrast agents or anesthetics;
* 9. Other circumstances that the investigator considers inappropriate for participation in the trial or that may pose significant risks to patients (such as inability to understand and/or follow the study procedures and/or follow up due to mental disorders, cognitive or emotional disorders)
* 10.The expected survival time is less than 1 year (such as patient with malignant tumor, advanced heart or lung diseases, etc.)
* 11.Participation in other interventional randomized clinical trials that may confound the outcome assessment of the trial;
* 12. Females who are pregnant, or those of childbearing, potential with positive urine or serum beta Human Chorionic Gonadotropin test