PLATELET INHIBITOR DRUG TRIAL IN CORONARY ANGIOPLASTY

通过扩张冠状动脉狭窄， 经皮冠状动脉成形术（PTCA）可以缓解心绞痛，改善运动 耐受性和左心室功能。 然而，再狭窄发生在 20-30%的扩张性狭窄在PTCA后3-6个月内发生， 必须限制患者活动，恢复抗心绞痛药物治疗， 重复PTCA或进行冠状动脉搭桥手术。 球囊扩张 动脉粥样硬化病变的血管内皮、内膜和中膜受损， 动脉 这可能会导致再狭窄通过血小板沉积，壁 血栓形成和内膜增生的机制， 类似于导致冠状静脉移植物（ACVG）闭塞的那些。 我们 已经证明双嘧达莫加阿司匹林治疗可以抑制 这些机制ACVG闭塞在动物模型中，延长缩短 冠心病患者的血小板存活率，并降低ACVG 术后早期和晚期患者的闭塞。 因此 在接受PTCA的患者中试验这些药物是合乎逻辑和必要的 在我们努力减少最初的主要缺点的过程中， 成功的PTCA治疗，即再狭窄率高。 一 前瞻性、双盲、随机、血小板抑制剂药物试验， 将在患者中进行双嘧达莫+阿司匹林与安慰剂的比较 接受PTCA，以评估药物在降低 再狭窄 治疗组和对照组的主要终点比较 对照组在PTCA术后6个月行冠状动脉造影， (1)成功进行PTCA的患者中， 扩张病变和（2）扩张病变的变化程度， 术后即刻至6个月。 法分析 PTCA前、PTCA后即刻和6个月时的血管造影狭窄 在PTCA后，将通过我们之前使用的2种方法进行 经验：（1）2组动脉造影片的一致阅读，每组2人 2次观察（Brensike等人的方法），以目视估计 动脉直径最大狭窄百分比;（2）光笔 在数字化平板电脑上勾画动脉病变轮廓， 电脑 次要终点包括新发冠状动脉事件（心肌梗死）， 梗死、死亡和需要冠状动脉旁路移植术，或 PTCA）。

By dilating coronary stenoses, percutaneous transluminal coronary angioplasty (PTCA) can relieve angina pectoris and improve exercise tolerance and left ventricular function. However, restenosis occurs in 20-30% of dilated stenoses within 3-6 months following PTCA making it necessary to restrict patient activities, resume antianginal medications, repeat PTCA, or perform coronary artery bypass surgery. Balloon dilatation of the atherosclerotic lesion damages the endothelium, intima, and media of the artery. This may lead to restenosis via platelet deposition, mural thrombus formation, and intimal proliferation by mechanisms that appear similar to those causing aortocoronary vein graft (ACVG) occlusions. We have demonstrated that dipyridamole plus aspirin therapy can supporess these mechanisms of ACVG occlusion in the animal model, prolong a shortened platelet survival in patients with coronary artery disease, and reduce ACVG occlusions in patients both early and later after the operation. Thus, a trial of these drugs in patients undergoing PTCA is a logical and necessary step in our efforts to reduce the major shortcoming of the initially successful PTCA therapy, namely the high rate of restenosis. A prospective, double-blind, randomized, platelet-inhibitor, drug trial with dipyridamole plus aspirin versus placebo will be conducted in patients undergoing PTCA to evaluate drug effectiveness in reducing the incidence of restenosis. The primary end points to be compared in the treated and control groups by coronary angiography performed 6 months after PTCA are (1) the percent of patients with successful PTCA who have restenosis of the dilated lesion and (2) the degree of change in the dilated lesion from immediately after PTCA to 6 months later. Determination of the degree of angiographic stenosis before PTCA, immediately after PTCA, and 6 months after PTCA, will be done by 2 methods with which we have had previous experience: (1) consensus reading of arteriograms by 2 groups of 2 observers on 2 occasions (method of Brensike et al) to visually estimate the maximal percent narrowing in arterial diameter and (2) light pen outlining of arterial lesions on a digitizing tablet interfaced with a computer. Secondary end points include new coronary events (myocardia infarction, death, and need for aortocoronary bypass graft operation or PTCA).