Mechanical thrombectomy(MT) has been recommended in patients with acute large vessel occlusion stroke(LVO) , especially for those with National Institutes of Health Stroke Scale (NIHSS) score ≥6. However, it is still unclear if patients with minor strokes and LVO also benefit from MT.The aim of this study was to evaluate the safety and efficacy of MT for acute LVO and mild symptoms.

This is a prospective cohort study of patients with with mild ischemic stroke (NIHSS Score <6) and LVO. Patients were divided into 2 groups: MT or medical management.Baseline data and clinical outcomes were compared. A independent clinical outcome was defined as a modified Rankin Scale score of 0 to 2 at 90 days. A excellent clinical outcome was defined as a modified Rankin Scale score of 0 to 1 at 90 days. Symptomatic intracranial hemorrhage(sICH) was the safety outcome.

Inclusion Criteria:

1. acute ischemic stroke within 24 hours of symptom onset presenting cortical symptoms (such as aphasia, somnolence,slow-minded,etc.) or vertigo with bilateral pathological signs;
2. age≥18 years old;
3. the NIHSS score before evaluation of thrombectomy<6;
4. large artery occlusion including Middle cerebral artery M1, proximal M2 segment, intracranial internal carotid artery and infarct core volume≤50ml and mismatch ratio>1.8 or basilar artery and posterior cerebral artery P1 occlusion

Exclusion Criteria:

1. Patients without prior functional independence (mRS score of >2)
2. Patients in intervention group with occlusive artery spontaneous recanalization in digital subtraction angiography
3. patients in control group with neurological worsening and received rescue thrombectomy