Waksman R, Ajani A E, White R L, Pinnow E, Dieble R, Bui A B, Taaffe M, Gruberg L, Mintz G S, Satler L F, Pichard A D, Kent K K, Lindsay J
Washington Hospital Center, Washington, DC, USA.
Circulation. 2001 May 15;103(19):2332-5. doi: 10.1161/01.cir.103.19.2332.
Intracoronary gamma-radiation reduces recurrent in-stent restenosis. Late thrombosis (>30 days after radiation therapy) is identified as a serious complication. The Washington Radiation for In-Stent Restenosis Trial (WRIST) PLUS, which involved 6 months of treatment with clopidogrel and aspirin, was designed to examine the efficacy and safety of prolonged antiplatelet therapy for the prevention of late thrombosis.
A total of 120 consecutive patients with diffuse in-stent restenosis in native coronary arteries and vein grafts with lesions <80 mm underwent percutaneous coronary transluminal angioplasty, laser ablation, and/or rotational atherectomy. Additional stents were placed in 34 patients (28.3%). After the intervention, a closed-end lumen catheter was introduced into the artery, a ribbon with different trains of radioactive (192)Ir seeds was positioned to cover the treated site, and a dose of 14 Gy to 2 mm was prescribed. Patients were discharged with clopidogrel and aspirin for 6 months and followed angiographically and clinically. All patients but one tolerated the clopidogrel. The late occlusion and thrombosis rates were compared with the gamma-radiation-treated (n=125) and the placebo patients (n=126) from the WRIST and LONG WRIST studies (which involved only 1 month of antiplatelet therapy). At 6 months, the group receiving prolonged antiplatelet therapy had total occlusion and late thrombosis rates of 5.8% and 2.5%, respectively; these rates were lower than those in the active gamma-radiation group and similar to those in the placebo historical control group.
Six months of clopidogrel and aspirin and a reduction in re-stenting for patients with in-stent restenosis treated with gamma-radiation is well tolerated and associated with a reduction in the late thrombosis rate compared with a similar cohort treated with only 1 month of clopidogrel and aspirin.
冠状动脉内伽马射线照射可降低支架内再狭窄的复发率。晚期血栓形成（放疗后>30天）被视为一种严重并发症。华盛顿支架内再狭窄放射治疗试验（WRIST）PLUS旨在研究延长抗血小板治疗预防晚期血栓形成的疗效和安全性，该试验涉及使用氯吡格雷和阿司匹林进行6个月的治疗。
总共120例连续的患者，其自身冠状动脉和静脉移植物中存在弥漫性支架内再狭窄，病变长度<80mm，接受了经皮冠状动脉腔内血管成形术、激光消融和/或旋磨术。34例患者（28.3%）植入了额外的支架。干预后，将一个封闭端腔导管插入动脉，放置一条带有不同序列放射性（192）铱种子的带，以覆盖治疗部位，并规定给予2mm处14Gy的剂量。患者出院时服用氯吡格雷和阿司匹林6个月，并进行血管造影和临床随访。除1例患者外，所有患者均耐受氯吡格雷。将晚期闭塞和血栓形成率与WRIST和LONG WRIST研究中接受伽马射线照射的患者（n=125）和安慰剂患者（n=126）（这两项研究仅涉及1个月的抗血小板治疗）进行比较。在6个月时，接受延长抗血小板治疗的组总闭塞率和晚期血栓形成率分别为5.8%和2.5%；这些比率低于活性伽马射线照射组，与安慰剂历史对照组相似。
与仅接受氯吡格雷和阿司匹林1个月治疗的类似队列相比，接受伽马射线照射治疗的支架内再狭窄患者服用6个月氯吡格雷和阿司匹林以及减少再次支架植入耐受性良好，且晚期血栓形成率降低。
