Drug-Eluting Coronary Stent Very Late Thrombosis Revisited

Compared to bare-metal stents (BMS), drug-eluting stents (DES) provide a significant additional reduction in restenosis rates and the need for coronary reinterventions. However, compared to BMS, the risk of very late stent thrombosis (ST) appears to be marginally higher accounting for 0.2-0.6% annual incidence for up to 3 years and possibly even longer following implantation. Risk reduction strategies include meticulous implantation technique, identification of patients with increased thrombotic risk, exclusion of patients scheduled in short term for major elective surgeries, and extended dual antithrombotic treatment for a minimum of 12 months. Future risk avoidance strategies are briefly reviewed and commented.     

Simultaneous Very Late Stent Thrombosis in Multiple Coronary Arteries

We report 2 noteworthy cases of very late stent thrombosis presenting as ST-segment-elevation myocardial infarction, with vastly different manifestations. Both patients were women who had histories of multivessel percutaneous coronary intervention with first-generation sirolimus-eluting stents, in 2005 and 2006. On the more recent occasions reported here, one underwent successful multivessel primary percutaneous coronary intervention, while the other underwent successful multivessel “plain old balloon angioplasty.” Both were discharged from the hospital with advice to stop smoking and to follow a lifelong regimen of aspirin and clopidogrel.On the basis of these two cases and our review of the current literature, we ask whether it is now prudent to recommend lifelong dual antiplatelet therapy after drug-eluting stent deployment. Moreover, in order to account for cases of stent thrombosis that occur ≥5 years after drug-eluting stent implantation, should we perhaps suggest the addition of “extremely late stent thrombosis” to the existing Academic Research Consortium classification?Key words: Aspirin, clopidogrel, coronary restenosis/etiology, coronary thrombosis/etiology, drug delivery systems/adverse effects, immunosuppressive agents, paclitaxel, platelet aggregation inhibitors/therapeutic use, sirolimus/therapeutic use, stent thrombosis, stents, drug-eluting/adverse effects, ST-elevation myocardial infarction, very late stent thrombosisStent thrombosis after percutaneous coronary intervention (PCI) remains a serious concern for both cardiologists and patients. The incidence of stent thrombosis within the first 30 days in patients randomized to receive sirolimus-eluting stents (SES) in clinical trials is reported to be no different from that in patients randomized to a control group receiving bare-metal stents.¹ Stent thrombosis has been reported as late as 17 months,² and more recently as late as 26 months, after SES implantation.³ We report 2 cases of simultaneous very late stent thrombosis in multiple coronary arteries ≥5 years after drug-eluting stent (DES) implantation, presenting as an ST-segment-elevation myocardial infarction (STEMI) despite a regimen of aspirin in patient 1 and both aspirin and clopidogrel in patient 2.     

合理看待药物洗脱支架晚期血栓问题

冠状动脉支架现广泛应用于冠心病的介入治疗中。支架内血栓是金属裸支架和药物洗脱支架的一个并发症,可导致心肌梗死或死亡。最近,药物洗脱支架引起晚期支架内血栓的问题引起人们的广泛关注。支架血栓的危险因素包括操作因素(如支架贴壁不良、置入支架的数目、支架长度及夹层)、患者及病变因素、过早停用抗血小板药物以及支架释放的药物使内皮延迟愈合等。现对支架晚期血栓的概念、发生的危险因素、防治措施等进行探讨。     

血管内超声在冠状动脉药物洗脱支架晚期血栓研究中的应用

药物洗脱支架与金属裸支架相比,减少了再狭窄的发生率,但其长期安全性却引起了人们的注意。支架置入30 d以后出现的晚期支架内血栓问题成为目前介入心脏病学的研究热点。晚期支架内血栓发生率低,但一旦发生后果严重。有研究显示其发生的原因可能包括动脉的延迟愈合、动脉瘤形成及支架贴壁不良等。现就血管内超声在冠状动脉药物洗脱支架晚期血栓研究中的应用进展做一评述。     

药物洗脱支架与晚期、极晚期支架血栓

第一代药物洗脱支架在显著降低再狭窄率的同时,也带来了支架血栓尤其是晚期、极晚期支架血栓这一棘手问题.晚期、极晚期支架血栓虽然发生率较低,但一旦发生往往带来灾难性后果.晚期、极晚期支架血栓的发生机制包括血管再内皮化延迟、多聚物过敏反应、支架晚期贴壁不良及新生动脉粥样硬化斑块破裂等.第二代和第三代药物洗脱支架在安全性上可能优于第一代.生物全降解支架代表了药物洗脱支架的发展方向,有望从根本上解决药物洗脱支架的晚期和极晚期支架血栓问题.现对近年来药物洗脱支架晚期及极晚期支架血栓的发生机制及新一代药物洗脱支架的研究进展做一综述.     

Very Late Angiographic Stent Thrombosis with Cyphertrade mark Stent Despite Being on Aspirin Therapy

Late angiographic stent thrombosis after Cyphertrade mark stent implantation has been reported to occur till approximately one year after the procedure and usually soon after the discontinuation of all antiplatelet medication.We report a case of very late stent thrombosis occurring 27 months (790 days) after stent implantation and 13 months after clopidogrel discontinuation despite being on regular aspirin. This case underlines the possible need for long-term dual antiplatelet therapy after implantation of drug-eluting stents.     

药物支架晚期血栓

药物支架很大程度上解决了支架内再狭窄的问题。但最近药物支架晚期血栓的问题倍受关注。现就可能导致药物支架晚期血栓的因素及支架的发展前景做一简要综述。     

支架内晚期血栓及其防治进展

早期和晚期支架内血栓给当前经皮冠状动脉介入治疗带来棘手的问题,可以导致非致命性心肌梗死和心源性死亡。晚期支架内血栓较少见但往往带来严重后果,多见于药物洗脱支架术后。支架内血栓的发生主要与支架置入技术、病变特征、双重抗血小板治疗效果、局部组织对雷帕霉素或紫杉醇等涂层药物的反应等因素有关。使用新一代药物洗脱支架可能减少晚期支架内血栓发生的风险。     

雷帕霉素涂层支架术后抗血小板治疗与支架内血栓形成

<正> 抗血小板治疗的中断对于支架内血栓形成的影响及对DES术后患者远期预后的影响尚未被充分的阐述。Takeshi Kimura等在日本的一项观察研究中(J-Cypher registry),纳入了10 778例置入雷帕霉素涂层支架的患者,分析其2年的结果。对这些患者2年随访期间的抗血小板治疗资料进行收集分     

Late Stent Thrombosis Associated with Heavy Exercise

Bare-metal stents are commonly used in the treatment of coronary artery disease. Stent thrombosis usually occurs within the first 48 hours after stent deployment. After a week, the incidence of thrombosis is low. Late stent thrombosis (after 30 days) is rarely seen; however, its clinical outcomes are severe 30-day mortality rates of 20% to 48% and myocardial infarction rates of 60% to 70%. Herein, we present the case and discuss the treatment of a patient who, after heavy exercise, experienced acute myocardial infarction due to late thrombosis in a bare-metal stent.A 54-year-old man presented with unstable angina pectoris. Coronary angiography revealed critical occlusion of the middle right coronary artery. A bare-metal stent was implanted, and he was discharged from the hospital on a medical regimen. Eleven months later, he presented with acute myocardial infarction, which had developed after heavy exercise. Coronary angiography revealed occlusion of the stent in the right coronary artery. After the occlusion was crossed with a guidewire, balloon angioplasty was applied, and Thrombosis-in-Myocardial-Infarction (TIMI)-3 flow was restored. The patient was asymptomatic during his 5-day hospitalization and was discharged on dual antiplatelet therapy.In addition to presenting this patient''s case, we discuss mechanisms that may contribute to late stent thrombosis, implications of the condition, and preventive therapy.Key words: Aspirin/administration & dosage/therapeutic use, blood vessel prosthesis implantation/adverse effects, coronary disease/therapy, coronary restenosis/etiology/pathology/prevention & control/therapy, coronary thrombosis/etiology/therapy, exercise/physiology, myocardial revascularization, platelet aggregation inhibitors/administration & dosage, postoperative complications/etiology, stents/adverse effects, treatment outcomeBare-metal stents are commonly used in the treatment of coronary artery disease. When stent thrombosis occurs, it is usually within the first 48 hours after deployment of the stent; after a week, the incidence of thrombosis is very low.¹ Late stent thrombosis (after 30 days) is rarely seen; however, its concomitant clinical outcomes are severe 30-day mortality rates of 20% to 48% and myocardial infarction rates of 60% to 70%.^2,3 Here, we discuss the case and treatment of a 54-year-old man who, after heavy exercise, experienced acute myocardial infarction consequent to late stent thrombosis. We present implications of the condition, possible contributory mechanisms, and preventive measures.     

动态支架显像功能在冠脉介入治疗中的应用

目的评价动态支架显像功能在介入治疗中不同病变的应用价值。方法自2011年9月至2012年8月(排除急性心肌梗死患者),连续完成100例应用动态支架显像功能指导的择期冠心病介入治疗患者,包括分叉病变、开口病变、左主干病变、再狭窄病变及慢性完全闭塞病变介入治疗中应用动态支架显像功能,同期完成介入治疗的同类病变(ACC/AHA分型)作为对照组,比较两组间介入治疗手术时间、造影剂用量和术后肌酐增加情况,评价动态支架显像在介入治疗中的作用。结果两组比较基线水平包括年龄、性别、高血压、糖尿病、吸烟、心肌梗死、体重指数无差别,病变类型、曝光时间、置入支架数量均无统计学差别(P>0.05),曝光时间(22.3±10.9与22.5±10.1min,P=0.259)相似,但研究组造影剂用量较对照组用量更少(101.9±34.1ml与114.4±41.7ml,p=0.021),差别有统计学意义,术后肌酐增加没有差异(11.41±3.14与2.15±3.37umol/l,P=0.109)。结论动态支架显像功能能准确指导支架支架串联及分叉病变完成最终对吻扩张、左主干开口病变支架置入后扩张球囊与支架关系定位、再狭窄病变再次介入治疗与既往置入支架串联以及扩张支架近端边缘球囊的准确定位,减少造影剂用量。