Inclusion Criteria:  Clinical diagnosis of ischemic stroke with National Institute of Health Stroke Scale (NIHSS) score of 1-8 An ischemic lesion on diffuse-weighted imaging located in the MCA perforator, or Heubner's artery territories or vertebro-basilar perforator territories at brain stem, with an axial diameter ≦ 20mm.-. Branch atheromatous disease, defined by a visible lesion in three or more axial MRI cuts in the MCA perforator or Heubner's artery territories or infarcts that extended from the basal surface of the brainstem. Ability to randomize within 24 hours of time last known free of new ischemic symptoms. Head CT or MRI ruling out hemorrhage or other pathology, such as vascular malformation, tumor, or abscess, that could explain symptoms or contraindicate therapy. Ability to tolerate high intensity medical therapy, including aspirin at a dose of 50-325 mg/day, clopidogrel with 300mg loading and 75mg after day 2 and high-intensity statin(either atorvastatin 40-80mg or rosuvastatin 20 mg/day). Pre-stroke mRS≦1  Exclusion Criteria:  Age < 20 years. In the judgment of the treating physician A candidate for thrombolysis, endarterectomy or endovascular intervention. Receipt of any intravenous or intra-arterial thrombolysis within 1 week prior to index event. Patients with more than 50% stenosis of the relevant arteries on magnetic resonance angiography (MRA), including intra- or extra-cranial internal carotid artery, middle cerebral artery or basilar artery. Patients with high risk of cardioembolic source, such as atrial fibrillation, acute myocardial infarction, severe heart failure or valvular heart disease. Other determined stroke etiology, such as vasculitis, shock, antiphospholipid antibody syndrome and etc. Gastrointestinal bleed or major surgery within 3 months prior to index event. History of nontraumatic intracranial hemorrhage. Clear indication for anticoagulation during the study period (deep venous thrombosis, pulmonary embolism or hypercoagulable state). Qualifying ischemic event induced by angiography or surgery. Severe non-cardiovascular comorbidity with life expectancy <3 months. Contraindication to clopidogrel, aspirin, atorvastatin or rosuvastatin Known allergy to clopidogrel, aspirin atorvastatin or rosuvastatin Severe renal (serum creatinine >2 mg/dL) or hepatic insufficiency (INR>1.2; ALT>40 U/L or any resultant complication, such as variceal bleeding, encephalopathy, or jaundice) Hemostatic disorder or systemic bleeding in the past 3 months Current thrombocytopenia (platelet count <100 x109/L) or leukopenia (<2 x109/L) History of drug-induced hematologic or hepatic abnormalities Anticipated requirement for long-term (>7 day) non-study antiplatelet drugs (e.g., dipyridamole, ticagrelor, ticlopidine), or NSAIDs. Low-density lipoprotein<70mg/dl without prior statin treatment in recent one year or within 2 days after recruitment