Bare-metal stent thrombosis two decades after stenting

Very late bare-metal stent (BMS) thrombosis is unusual in clinical practice. To the best of our knowledge, the latest that the thrombosis of a BMS has been reported is 14 years after implantation. Here, we describe a case of BMS thrombosis that occurred two decades after stenting. A 68-year-old male patient was admitted with acute anterior myocardial infarction. This patient had a history of BMS implantation in the left anterior descending coronary artery (LAD) 20 years previously. Immediate coronary angiography demonstrated acute thrombotic occlusion of the stent in the LAD. With this case, we are recording the latest reported incidence of BMS thrombosis after implantation.     

Neo-atherosclerosis in very late stent thrombosis of drug eluting stent

Background

Recent studies have described neo-atherosclerosis, developing inside the stent, as cause of very late stent thrombosis.

Case report

A 59-year-old man, with family history of coronary artery disease, presented to our Department because of anterior ST-segment elevation myocardial infarction. Two years before he had underwent percutaneous coronary intervention with multiple drug-eluting stents (DES) implantation on proximal-mid left anterior descending artery (LAD), and mid-right coronary artery (RCA), respectively. The angiogram revealed stent thrombosis with total occlusion of proximal LAD. Multiple passages with manual thrombus-aspiration catheter were successfully performed with improvement in TIMI flow. Optical Coherence Tomography (OCT) imaging revealed fully expanded stents without areas of inappropriate apposition to vessel wall; and mild to moderate intimal hyperplasia throughout the stented segment, with full covered stent struts; areas of ulcerated and ruptured plaque within the proximal struts of stented segment was depicted with intraluminal protruding material. Thus, an additional bare metal stent (BMS) was deployed inside and overlapping the previous in order to seal this plaque. OCT post procedure revealed optimal stent expansion and apposition, without residual protruding material. At 9-month follow-up patient was alive and free from symptoms. Coronary angiogram revealed patency of implanted stents without significant restenosis.

Conclusions

Neo-atherosclerosis with thrombosis on top of ruptured necrotic plaque core may play a role in the pathophysiology of very late stent thrombosis in both BMS and DES. Our report highlights the role OCT to assess the mechanism of VLST.     

High risk of stent thrombosis in the first 6 months after coronary stenting

Objectives

To estimate the incidence of stent thrombosis (ST) after early discontinuation of clopidogrel.

Background

Premature discontinuation of clopidogrel is the strongest risk factor for ST. In contrast, recent studies suggest that shorter dual antiplatelet therapy (DAPT) can be discontinued as soon as 3 months after stenting. However, these studies included very few ACS patients and were not powered for ST. Hence, little is known about the occurrence of ST in high‐risk populations when DAPT is discontinued early.

Methods

This is a subanalysis of The Dutch ST Registry 437 ST cases (mainly first‐generation DES and BMS). Acute coronary syndrome was the indication for index‐PCI in 74% of the patients. Clopidogrel discontinuation rates in ST patients and matched controls were used to calculate the absolute incidence of ST after early clopidogrel discontinuation.

Results

The overall rate of ST after cessation of clopidogrel was 4.6% (95%CI: 3.9‐5.4%), as compared to 1.7% (95%CI: 1.5‐1.9%) in patients who did not discontinue clopidogrel. The incidence of ST was 35.4% when clopidogrel was discontinued in the first 30 days after index‐PCI declining to 11.7% when clopidogrel was discontinued in the first 180 days.

Conclusions

This dedicated ST registry shows that ST rates were very high when clopidogrel was discontinued before 6 months after index‐PCI and therefore suggests that clopidogrel discontinuation in the first 6 months after ACS should be avoided.

     

不同双重抗血小板治疗时间对药物洗脱支架极晚期血栓患者预后的影响

目的：分析药物洗脱支架（DES）术后发生极晚期支架内血栓（VLST）的患者接受双重抗血小板治疗（DAPT）的情况,探讨不同DAPT持续时间对患者远期预后的影响。方法2006年1月至2013年2月,首都医科大学附属北京朝阳医院心脏中心共完成3945例急诊冠状动脉造影,入选经急诊造影证实为VLST的患者。根据随访期间是否仍持续使用DAPT,将患者分为持续DAPT组和对照组。比较两组患者的临床资料、造影及介入治疗资料以及抗血小板药物治疗情况。临床主要不良心血管事件（MACE）包括随访期间的非致死性心肌梗死（MI）,再发支架内血栓（ST）,靶血管重建率（TVR）以及死亡。探讨不同DAPT持续时间对患者远期预后的影响,并分析随访期间发生MACE的预测因素。结果共计有62例VLST患者纳入研究,其中男性55例,女性7例,年龄41～82（58.6±10.2）岁。VLST距第1次DES置入时间为12.5～84（38.7±18.1）个月。住院期间脑出血死亡1例,存活的61例患者随访5～88（32.1±19.1）个月。随访期间,又有17例患者出现MACE,Kaplan-Meier生存率分析提示无事件生存率为45.1%。末次随访时,坚持持续DAPT的患者38例,其中5例（13.2%）发生MACE,事件发生率明显低于对照组（54.2%,P＝0.001）。根据是否发生MACE事件将所有患者分为两组,Cox单因素分析提示再次置入第一代DES[危害率（hazard ratio,HR）：2.69,P＝0.04]和持续DAPT（HR：0.25,P＝0.01）为远期随访中MACE相关的预测因素。而多因素Cox分析则提示仅有持续DAPT是随访期间不发生MACE的唯一预测因素（HR：0.30,95% CI：0.09～0.97,P＝0.04）。结论 DES术后VLST患者远期预后情况欠佳,事件发生率较高。坚持DAPT可能有助于减少远期不良事件的发生。     

High incidence of recurrent in stent thrombosis after successful treatment of a first in stent thrombosis

Objectives: We attempted to investigate incidence and predictors of recurrent in stent thrombosis (IST) after successful treatment of a first IST. Background: The occurrence of recurrent IST after successful treatment of a first IST may be a decisive factor for patient clinical outcome. However, incidence and predictors of recurrent IST are currently poorly described in the literature. Methods: Between 2003 and 2005, 2,190 patients underwent a percutaneous coronary intervention in our center. During a median follow‐up of 19.4 months, 49 patients (2.24%) presented a first definite IST. Patients presenting with a first IST were followed during an additional median period of 40 months. Their baseline characteristics were listed and cardiovascular events especially recurrent IST as defined by the Academic Research Consortium definition were systematically indexed. Results: Altogether 39 (80%) patients were successfully treated with an effective reperfusion after percutaneous coronary intervention. Fourteen (36%) patients presented a recurrent IST and three presented multiple recurrent IST. The median occurrence time of recurrent IST was 5 days, range between 1 and 11 days. Multivariate analysis identified history of neoplasia (HR = 11.53, 95% CI 2.32–57.37, P = 0.003), residual diameter stenosis (HR = 1.15, 95% CI 1.02–1.29, P = 0.02), and residual dissection after treatment (HR = 8.78, 95% CI 1.85–41.62, P = 0.006), as independent predictors of recurrent IST. Conclusion: Recurrent IST is a frequent and early event after successful treatment of a first IST. Our results suggest that mechanical factors like residual dissection and residual diameter stenosis should be carefully tracked down. In addition, patients with multiple recurrent IST and the early time course of recurrent IST also suggest a potential role of inadequate antiplatelet therapy. © 2008 Wiley‐Liss, Inc.     

Simultaneous late stent thrombosis in two coronary arteries following drug-eluting stent implantation

Late stent thrombosis has emerged as an infrequent but serious complication of drug-eluting stent (DES) implantation. Premature cessation of dual antiplatelet therapy is the most common risk factor for its occurrence. In the era of multivessel stenting with DES, there is a potential for multivessel late stent thrombosis following cessation of dual antiplatelet therapy. We present a rare case of a patient who sustained simultaneous late stent thromboses in DESs implanted in two coronary arteries as a result of premature cessation of dual antiplatelet therapy.     

Very Late Stent Thrombosis after Discontinuation of Antiplatelet Agents during Anticoagulation Therapy in a Patient with Peri-stent Contrast Staining after Implantation of a Second-generation Drug-eluting Stent

A 54-year-old man was admitted to our hospital due to intermittent chest pain. He had a history of acute myocardial infarction, and peri-stent contrast staining had been observed at the stent implantation site. The patient previously underwent anticoagulation therapy for left ventricular thrombus and antiplatelet therapy to prevent stent thrombosis. More than one year after implantation of a drug-eluting stent, antiplatelet drugs were discontinued, and anticoagulant alone was prescribed according to the guidelines, which resulted in very late stent thrombosis. The risks of both bleeding and thrombosis must be fully considered when deciding whether or not to discontinue antiplatelet therapy during anticoagulation therapy.     

Stent thrombosis

Intense investigation continues on the pathobiology of stent thrombosis (ST) because of its morbidity and mortality. Because little advance has been made in outcomes following ST, ongoing research is focused on further understanding predictive factors as well as ST frequency and timing in various patient subsets, depending upon whether a drug-eluting stent or bare-metal stent has been implanted. Although the preventive role of antiplatelet therapies remains unchallenged, new data on genomics and variability in response to antiplatelet therapy, as well as the effects of novel therapeutic agents and duration of therapy, have become available. The goal remains identification of patients at particularly increased risk of ST so that optimal prevention strategies can be developed and employed.     

The lack of endothelization after drug-eluting stent implantation as a cause of fatal late stent thrombosis

The authors present a fatal case of late thrombosis of paclitaxel-eluting stent implanted in the left main stem occurring 6 months after the procedure and 3 weeks after the cessation of clopidogrel. An autopsy has shown the lack of endothelization of deployed stent.     

Very late [corrected] thrombosis of a sirolimus-eluting stent.

We report the case of a 67-year-old man who presented with a [corrected] non-ST-elevation acute myocardial infarction 41 months after implantation of a sirolimus-eluting stent in his left circumflex coronary artery. Coronary angiography revealed stent thrombosis.     

冠状动脉西罗莫司洗脱支架置入后晚期支架内血栓形成分析

目的分析冠状动脉药物洗脱支架置入后晚期支架内血栓形成的临床相关因素。方法回顾性分析2003年7月至2005年1月我院置入西罗莫司洗脱支架的1304例冠心病患者中发生晚期支架内血栓的8例患者的临床资料、冠状动脉病变特点、支架释放情况以及术后的抗血小板治疗等相关因素。结果8例患者平均年龄（51±10）岁、7例为急性冠状动脉综合征患者且伴有多项心血管病危险因素,仅1例患者伴有左室功能不全,无肾功能不全患者;多支冠状动脉病变患者6例且病变较复杂,包括闭塞、分叉、开口和弥漫长病变;支架释放压力平均（1175.37±167．19）kPa（11．60±1．65atm）,全部患者未用高压球囊进行后扩张;双重抗血小板治疗平均时间为（157．5±41．7）d,1例在停用氯吡格雷第7天、2例在服用阿司匹林和氯吡格雷治疗期间、5例停用氯吡格雷6个月后出现支架内血栓,平均血栓发生时间为术后（450．3±344．7）d,5例表现为急性心肌梗死;1例死亡,5例再次置入西罗莫司洗脱支架,术后随访无症状,1例药物治疗。结论发生晚期支架内血栓的冠心病患者多表现为急性冠状动脉综合征、伴有多项心血管病危险因素;多支、复杂冠状动脉病变;支架低压释放,置入后未行后扩张;双重抗血小板治疗时间短。发生晚期支架内血栓患者预后差,死亡率较高,再次置入西罗莫司洗脱支架是安全、有效的。     

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.     

Use of anti-GP IIb-IIIa in acute thrombosis after intracoronary stent implantation

Acute occlusion of coronary stents still occurs in 0.5–2% of patients. The usefulness of GP IIb-IIIa receptor inhibitors has never been evaluated in this indication. After 1,454 stent implantations, acute occlusion occurred in 16 patients. Direct percutaneous transluminal coronary angioplasty (PTCA) was immediately performed. In eight patients, no recurrent thrombosis occurred during the 15 min following PTCA, and abciximab infusion was started after this period. In six patients, immediate recurrent thrombosis occurred in the stent. In these cases, an intravenous bolus of abciximab followed by a new inflation at low pressure was performed. Fifteen min after the bolus, stable TIMI 3 flow was restored in all six cases, and no thrombus or haziness remained. In two patients, a TIMI 0 flow persisted despite PTCA and the use of a bolus of abciximab. No recurrent ischemic symptoms were observed before hospital discharge. Abciximab in combination with balloon angioplasty can be used safely to control acute thrombosis after stent deployment. Cathet. Cardiovasc. Diagn. 43:105–107, 1998. © 1998 Wiley-Liss, Inc.