PLATELET INHIBITOR DRUG TRIAL IN CORONARY ANGIOPLASTY

通过扩张冠状动脉狭窄，经皮腔内冠状动脉 血管成形术(PTCA)可以缓解心绞痛和改善运动 耐受性和左心功能。然而，再狭窄发生在 20-30%的扩张性狭窄在PTCA术后3-6个月内 有必要限制患者的活动，恢复抗心绞痛药物治疗， 重复经皮冠状动脉腔内成形术，或进行冠状动脉搭桥术。气囊扩张术 动脉粥样硬化损害血管内皮、内膜和中膜。 动脉。这可能会通过血小板沉积导致再狭窄，附图 血栓的形成和血管内膜的增殖 类似于导致主动脉-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疗法可以抑制 这些机制在ACVG阻断动物模型中，延长了缩短的 冠心病患者的血小板存活和ACVG降低 术后早期和晚期患者均有闭塞。因此，一个 在接受PTCA的患者中试验这些药物是合乎逻辑和必要的 我们努力减少最初的主要缺点 PTCA治疗成功，即再狭窄率高。一个 前瞻性、双盲、随机、血小板抑制剂药物试验 双嘧达莫联合阿司匹林和安慰剂将在患者中进行 采用经皮冠状动脉腔内成形术(PTCA)评价药物对降低心绞痛发生率的疗效。 血管再狭窄。要比较的主要终点在处理后和 PTCA术后6个月行冠状动脉造影术的对照组为 (1)PTCA术后再狭窄患者的百分比 扩大的病变和(2)扩大的病变的变化程度 术后即刻至6个月后。确定的程度 PTCA前、PTCA后即刻和6个月的血管造影狭窄 经皮冠状动脉腔内成形术后，将通过2种方法，我们已经与以前 经验：(1)两组2人共同阅读动脉图 2次观察(Brensike等人的方法)以目测估计 动脉内径最大狭窄百分比和(2)光笔 在数字化平板上勾勒出动脉病变的轮廓 电脑。次要终点包括新的冠状动脉事件(心肌 脑梗塞、死亡和需要行主动脉-冠状动脉搭桥术或 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).