Interventions: Patients in both arms will be admitted at acute stroke units (or Intensive Care Unit if needed) and treated following the Chinese Guidelines for the Early Management of Patients With Acute Ischemic Stroke. Concomitant medications and non-pharmacological therapies will be recorded. If a decision of stopping support life measures is adopted, this will be recorded in the Case Report Form (CRF).A maximum of six attempts to retrieve the thrombus in a single vessel can be made with any Solitaire device or aspiration. In case an atherosclerotic lesion is found underlying the occlusive lesion angioplasty/stenting through detachment of the Solitaire device will be allowed.