Ellahham Samer
Paragon Cardiovascular Foundation, Falls Church, VA, USA.
South Med J. 2008 Mar;101(3):273-83. doi: 10.1097/SMJ.0b013e318164705a.
Atherothrombosis describes the superimposition of a thrombus on a ruptured atherosclerotic plaque, and is the primary cause of acute ischemic events. Atherothrombosis is a generalized and progressive process with an inflammatory component. Patients with disease in one vascular bed are at risk of disease in another, a concept known as "cross-risk." Platelet adhesion, activation, and aggregation in the final stage of atherothrombosis are ultimately responsible for arterial occlusion and consequent ischemia. Therefore, antiplatelet therapy is an effective treatment choice for secondary prevention. Clopidogrel, an adenosine diphosphate receptor antagonist, given alone or in combination with aspirin, may benefit secondary prevention of ischemic events. Current treatment guidelines suggest the use of a combination of these two agents for secondary prevention where appropriate. However, data conflict regarding the efficacy of antiplatelet therapy for primary prevention. A recent meta-analysis demonstrated that aspirin significantly reduces the risk of first myocardial infarction in both men and women. The recent Clopidogrel for High Atherothrombotic Risk and Ischemic Stabilization, Management, and Avoidance trial, which evaluated the effects of clopidogrel plus aspirin compared with aspirin alone, seems to support the use of dual antiplatelet therapy in secondary prevention, but suggests that it may not be more effective than aspirin alone in primary prevention.
动脉粥样硬化血栓形成是指血栓叠加在破裂的动脉粥样硬化斑块上，是急性缺血事件的主要原因。动脉粥样硬化血栓形成是一个具有炎症成分的全身性渐进过程。一个血管床出现病变的患者在其他血管床也有发病风险，这一概念称为“交叉风险”。动脉粥样硬化血栓形成最后阶段的血小板黏附、激活和聚集最终导致动脉阻塞及随之而来的缺血。因此，抗血小板治疗是二级预防的有效治疗选择。氯吡格雷，一种二磷酸腺苷受体拮抗剂，单独使用或与阿司匹林联合使用，可能对缺血事件的二级预防有益。目前的治疗指南建议在适当情况下联合使用这两种药物进行二级预防。然而，关于抗血小板治疗用于一级预防的疗效，数据存在冲突。最近一项荟萃分析表明，阿司匹林可显著降低男性和女性首次心肌梗死的风险。最近的氯吡格雷用于高动脉粥样硬化血栓形成风险和缺血稳定、管理及预防试验，比较了氯吡格雷加阿司匹林与单独使用阿司匹林的效果，似乎支持在二级预防中使用双重抗血小板治疗，但表明在一级预防中它可能并不比单独使用阿司匹林更有效。
