不稳定性心绞痛4【精品PPT】.pptVIP

* 目前临床常用的抗栓药物包括抗凝、溶栓和抗血小板药物，它们在血栓形成凝血机制中的作用位点各不相同，如上图所示。抗血小板药物包括ASA、噻蒽并吡啶类（噻氯吡啶和氯吡格雷）以及糖蛋白IIb/IIIa受体抑制剂（阿昔单抗、埃替巴肽、替罗非班）。 胶原-内源性凝血 组织因子-外源性 * SLIDE 29 Platelets bear receptors for several activating mediators, including thromboxane A2, thrombin, ADP, among others. These mediators activate platelets through a number of internal responses, ultimately resulting in activation of the fibrinogen binding site, namely the glycoprotein IIb/IIIa receptor. Binding of fibrinogen by the activated glycoprotein IIb/IIIa receptor results in platelet aggregation and thrombus formation. Clopidogrel and aspirin both have antiplatelet activity. This arises through different mechanisms of action, with each agent acting at different stages in the cascade leading to platelet aggregation. Aspirin blocks platelet activation by inhibition of the thromboxane A2 pathway. Clopidogrel is an ADP receptor antagonist. Pre-clinical and clinical experience with the ADP receptor antagonist ticlopidine in combination with aspirin has confirmed that they have synergistic effects. The randomised clinical trials that have been performed (Hall et al. 1996, Sch?mig et al. 1996, Bertrand et al. 1998, Urban et al. 1998, Leon et al. 1998) provided the rationale for further investigation into the potential for synergistic efficacy of clopidogrel and aspirin. Bertrand ME, Legrand V, Boland J et al. (1998) Randomized multicenter comparison of conventional anticoagulant versus antiplatelet therapy in unplanned and elective coronary stenting. The full anticoagulation versus aspirin and ticlopidine (fantastic) study. Circulation 98:1597-1603. Hall P, Nakamura S, Maiello L et al. (1996) A randomised comparison of combined ticlopidine and aspirin therapy alone after successful intravascular ultrasound-guided stent implantation. Circulation 93:215-222. Leon MB, Baim DS, Popma JJ et al. (1998) A clinical trial comparing three antithrombotic-drug regimens after coronary-artery stenting. NEJM 339:1665-71.