氯吡格雷是非心源性缺血性卒中(NCIS)治疗指南推荐被广泛使用的药物。我们在前期"负荷剂量氯吡格雷治疗急性脑梗死"的随机双盲多中心临床研究中发现，某些患者可能存在氯吡格雷抵抗(CR),即对氯吡格雷低或无反应，这不但造成巨额医疗浪费，还可能导致卒中再发。但目前临床上如何识别CR人群，并对其进一步干预治疗仍不清楚。我们以服用氯吡格雷的急性NCIS患者为研究对象，利用流式细胞仪测定患者氯吡格雷治疗前及一周后的VASP磷酸化，从实验室评价其抗血小板聚集功能；并通过基因测序观察编码氯吡格雷代谢CYP2C19基因多态性。同时建立临床数据库，随访监测患者服用氯吡格雷一年后缺血性血管事件包括卒中的发生率，分析VASP磷酸化、CYP2C19基因多态性与临床终点血管事件发生的关系。我们希望从实验室生物学指标和遗传学特性识别国人非心源性缺血性卒中的CR人群，使基础研究向临床应用转化，为进一步治疗提供依据。

Clopidogrel is recommended by guilelines to reduce the risk of recurrent stroke and other cardiovascular events in patients with non-cardioembolic ischemic stroke(NCIS). In our previous clinical trial "Clopidogrel of Loading Dosage to Treat Acute Ischemic Stroke in China" ,some patients may have clopidogrel resistance(CR), in which clopidogrel has no or low response in inhibiting platelet aggregation. Some NCIS patients may have stroke recurrence despite taking routine clopidogrel, theoretically it has closely related with CR.How to distinguish NCIS patients with CR and further treatment for them is still unclear.In our study，acute NCIS inpatients who will take clopidogrel at least 1 year are enrolled. We use a flow cytometry vasodilator stimulated phosphoprotein (VASP) phosphorylation assay before and after a week taking clopidgorel to evaluate the clopidogrel efficacy of inhibiting platelet aggregation. The CYP2C19 polymorphism in these patients will also be determined by genetic test. The medical record of these patients will be collected in detail and all of them will be observed closely in a follow up 1 year period. The relationship between the incidence of recurrent stroke or other cardiovascular events at endpoint and VASP phosphorylation and CYP2C19 polymorphism will be analysed. We want to distinguish the NCIS patients with CR from the laboratorial biological-index and genetic characteristics, to promote the laboratorial research to clinical application transformation, so that it will provide a basis for further treatment in NCIS patients with CR.