PCI术后冠状动脉支架内血栓形成原因分析及对策

目的探讨冠状动脉介入术后支架内血栓形成的相关原因及对策,进一步提高其诊治水平。方法回顾性分析13例支架内血栓形成患者的临床及冠状动脉造影特点及处理措施。结果支架贴壁、膨胀不良、未完全覆盖病变,分叉病变,停服阿斯匹林、氯吡格雷和（或）药物抵抗等为支架内血栓形成的主要原因。结论急性和亚急性支架内血栓形成可能与技术因素有关支架贴壁不良等;晚期和极晚期支架内血栓可能与支架再狭窄、双联抗血小板药物治疗不当有关。强化抗血小板治疗、血栓抽吸导管负压抽吸,反复球囊扩张或重新置入支架是支架内血栓形成的主要治疗方法。     

药物洗脱支架置入术后晚期、极晚期支架内血栓形成的光学相干断层成像分析

目的:应用光学相关断层成像(OCT)分析药物洗脱支架置入术后晚期、极晚期支架内血栓形成的可能机制。方法:入选2011-01-2017-12经遵义医学院附属医院行冠状动脉(冠脉)造影明确诊断晚期、极晚期支架内血栓形成患者8例。8例患者在PCI术中均行OCT检查。回顾性分析8例患者的临床资料、PCI过程及OCT图像特征。结果:7例伴有多个心血管危险因素,2例合并轻度左心功能不全。首次支架置入至发生支架血栓的平均时间(818±651) d;双联抗血小板服用平均时间(312.8±76.3) d;低密度脂蛋白胆固醇(LDL-C)平均水平为(3.44±1.35) mmol/L,均未达到目标值;1例在术后停用双联抗血小板3个月、2例在服用双联抗血小板期间、5例在单用阿司匹林期间发生支架内血栓;6例置入依维莫司药物支架,1例行支架内非顺应性高压球囊扩张,1例行紫杉醇药物球囊治疗。OCT图像特征:7例患者支架内异质性新生内膜形成,5例为支架内新生动脉粥样硬化伴斑块破裂,2例为支架内新生动脉粥样硬化伴斑块侵蚀;1例出现严重支架贴壁不良,贴壁不良比例达66.2%;6例患者出现不同程度的支架小梁无内膜覆盖,平均为(10.4±6.2)%;5例支架内见红血栓,3例支架内见白血栓。结论:晚期、极晚期支架内血栓患者首次及再次住院多表现为急性冠脉综合征与高LDL-C水平。支架内新生动脉粥样硬化、支架贴壁不良是导致晚期、极晚期支架内血栓形成的主要原因之一。OCT的应用有助于明确晚期和极晚期支架内血栓形成的机制。     

冠状动脉支架内血栓与药物洗脱支架的安全性

最近,药物洗脱支架的安全性问题引起了人们的广泛关注。目前资料表明药物洗脱支架与金属裸支架相比并不引起更多的早、晚期支架内血栓发生,但极晚期支架内血栓形成的风险增加。药物洗脱支架明显降低支架内再狭窄的发生和靶病变的再次血运重建率,其有效性仍优于金属裸支架,尤其对于糖尿病等再狭窄高危患者。根据患者的临床具体情况合理选择支架非常重要。现综述冠状动脉支架内血栓与药物洗脱支架安全性的研究进展。     

晚期支架贴壁不良研究进展

与裸金属支架相比,药物洗脱支架植入后更易发生支架贴壁不良。血管内超声研究证实,引起晚期支架贴壁不良的主要机制是正性重构。发生支架内血栓的部位有的存在支架贴壁不良现象,由此推测,晚期支架贴壁不良可能会引起支架内血栓形成。支架贴壁不良与临床不良事件的关系尚需进一步研究。     

晚期支架贴壁不良研究进展

与裸金属支架相比,药物洗脱支架植入后更易发生支架贴壁不良。血管内超声研究证实,引起晚期支架贴壁不良的主要机制是正性重构。发生支架内血栓的部位有的存在支架贴壁不良现象,由此推测,晚期支架贴壁不良可能会引起支架内血栓形成。支架贴壁不良与临床不良事件的关系尚需进一步研究。     

药物洗脱支架术后血栓致急性冠状动脉综合征病因分析及处理评价

目的:分析药物洗脱支架术(DES)后支架内血栓形成导致急性冠状动脉综合征的影响因素。方法:分析38例DES术后形成支架内血栓形成患者的临床特点、冠状动脉病变特点、手术相关资料及患者发生急性冠状动脉综合征后的临床表现,处理措施和预后情况。结果:患者冠状动脉造影显示病变特点比较复杂,其中B2/C型病变占到了71%,分叉病变、慢性完全闭塞(CTO)病变、弥散长病变以及小血管病变也占到了相当大的比例,反映了真实的临床情况;38例患者中52.6%表现为急性ST段抬高心肌梗死,29%的患者表现为急性非ST段抬高心肌梗死;支架内血栓中急性、亚急性血栓形成占63%,晚期及迟发晚期血栓形成占37%;绝大多数患者成功接受了再次血运重建治疗,其中有31.6%的患者死亡;2例患者血小板聚集率≥50%,发生率为8.3%;4例接受冠脉内超声(IVUS)检查的患者结果显示:支架近端贴壁不良1例,支架远端残余夹层1例,支架内膜增生不完全1例,支架两端动脉瘤形成1例。结论:DES术后支架内血栓形成与患者的冠状动脉病变复杂程度、术后抗血小板治疗不充分、支架贴壁不良、夹层形成、内膜增生不完全以及动脉瘤的发生等因素相关,支架内血栓形成(ST)后多数表现为ST段抬高心肌梗死(STEMI),尽管大部分能成功再次血运重建治疗,但死亡率仍然较高(31.6%)。     

药物洗脱支架术后靶病变部位再发急性ST段抬高型心肌梗死的光学相干断层成像评价

目的应用光学相干断层成像(OCT)评价冠脉药物洗脱支架术后靶病变部位再发急性ST段抬高型心肌梗死(STEMI)患者的影像特征。方法回顾性分析行药物涂层支架(DES)植入,冠脉造影(CAG)证实靶病变部位再发STEMI的15例患者。应用OCT评价罪犯血管靶病变部位影像特点。结果 15例DES术后再发STEMI患者中,罪犯血管前降支(LAD)9例,右冠脉(RCA)4例,回旋支(LCX)2例。靶病变部位影像特征:CAG均表现为支架内血栓形成,4例急性血栓形成,3例亚急性血栓形成,5例晚期血栓形成,3例极晚期血栓形成。OCT表现为3例支架边缘夹层;5例支架贴壁不良(其中2例正性血管重构继发获得性贴壁不良);2例病变覆盖不全;2例支架内新生粥样硬化斑块(NAP)形成伴破裂;2例支架内皮化不全;1例表现仅为血栓形成。结论支架边缘夹层、贴壁不良、覆盖不全以及支架内NAP破裂均可导致支架术后靶病变部位再发STEMI,OCT对该类患者治疗有指导意义。     

极晚期支架内血栓的研究进展——发病机制及防治策略

药物洗脱支架应用于临床后,支架血栓问题引起广泛关注。目前的研究资料表明药物支架与金属裸支架相比并不引起更多的早、晚期支架内血栓的发生,但极晚期支架血栓形成的风险增加。极晚期支架发生机制复杂,临床多表现为严重的心血管事件,应予以积极防治。现综述极晚期支架内血栓的相关研究进展。     

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。     

冠状动脉支架内血栓形成(附5例报告)

目的分析冠状动脉支架内血栓形成的临床相关因素。方法回顾性分析571例冠状动脉支架治疗中的5例支架内血栓形成患者的临床资料、冠状动脉造影结果以及围手术期的抗血栓治疗等相关因素。结果5例急性冠状动脉综合征患者6处靶病变支架内血栓形成,其中3处为C型病变,4处置入药物洗脱支架。支架内血栓形成的原因:1处为支架不完全贴壁,2处支架不能完全覆盖病变,2例为患者抗血栓治疗不充分。结论冠状动脉支架内血栓形成可能与下列因素相关:(1)急性冠状动脉综合征;(2)长病变,支架贴壁不好,支架没有完全覆盖病变,使用药物涂层支架;(3)不充分的抗血栓治疗。     

New technique for prepping the Johnson & Johnson stent delivery system

Current prepping of the Johnson & Johnson stent deployment balloon can be suboptimal. This simple technique allows for an improved preparation of the stent delivery balloon prior to deployment, resulting in less air in the balloon during inflation. Cathet. Cardiovasc. Diagn. 41:440–441, 1997. © 1997 Wiley-Liss, Inc.     

“Procedural trauma risks longitudinal shortening of the promus element™ stent platform”

This case series raises further awareness of the potential for longitudinal shortening with the Promus Element? (Boston Scientific, MN) drug‐eluting stent (DES) platform. With safety at the forefront of DES development, newer generation systems are utilizing thinner platforms with little or no polymer. Although these contemporary, ultrathin platforms also improve conformability and deliverability, specific design characteristics might inadvertently reduce longitudinal strength. To date, there are no randomized data addressing this issue in vivo for any stent platform, with opinion based on individual experience and bench testing. We report five cases of longitudinal shortening with the Promus Element stent occurring in our institution over a 15‐month period. During the same period, we experienced only isolated cases with other second generation DES platforms. Our experience supports recently published bench‐top data correlating the two‐link design of this platform with the risk of compression. © 2012 Wiley Periodicals, Inc.     

Different vascular response to concurrent implantation of sirolimus- and zotarolimus-eluting stents in the same vessel

Drug-eluting stents (DES) have become routine therapy in clinical practice because restenosis is significantly reduced in patients treated with these devices. New generations of DES bearing newer antiproliferative drugs have been developed. Sirolimus was the first antiproliferative drug eluted by a DES (SES) while Zotarolimus represents a sirolimus-derived, newer antiproliferative drug borne by a different kind of DES (ZES). This report describes two cases of different vascular response to concurrent side by side implantation of SES and ZES in the same vessel and highlights significant early restenosis of ZES as compared with SES.     

Application of an enhanced device to transluminal retrieval of malappositioned coronary stents: An experimental study

Objectives

This study investigated the application of a novel enhanced device to retrieval of deployed stents in a porcine coronary model.

Background

Recurrence of in‐stent restenosis and stent thrombosis still remains to be resolved. Under these conditions, it is sometimes necessary to retrieve malfunctional stents responsible for thrombosis. However, few data exist regarding the feasibility and safety of retrieval device use in previously deployed coronary stents.

Methods

We have developed an enhanced device consisting of an asymmetric forceps, conducting shaft (1.6 mm diameter, 150 cm length), and control handle. Bare‐metal stents (3 mm diameter) were implanted in four pigs to create a malapposition model. Coronary artery injury was evaluated by intravascular ultrasound (IVUS) and histological imaging on the first and 14th days.

Results

The device was delivered to the coronary artery using the existing catheter (7 Fr). After opening the forceps, the blade was forced into the space between the vessel wall and the stent, and the stent struts were then grasped with the forceps. This was then pulled back into the catheter, still grasping the stent struts with the forceps. All stents were successfully retrieved by this method (n = 4). On the first day, no apparent vessel wall injury was detectable by IVUS, although histological findings revealed damage to endothelial monolayer on retrieval of deployed stent. On the 14th day, mild intimal thickening was observed by IVUS and histology.

Conclusions

These results demonstrate that the present device can be applied to transluminal retrieval of acquired malappositioned coronary stents.

     

Clinical applications of a new enhanced stent imaging technology

Enhanced Stent Imaging (ESI) refers to a rapidly evolving class of imaging tools that seek to provide enhanced visualization of coronary stent architecture with minimal disruption to the catheterization laboratory workflow. Various ESI stent platforms are available, all of which utilize a brief cine acquisition of a deflated balloon within a stent to generate a motion‐corrected, enhanced image of the stent. The enhanced image permits detailed assessment of stent architecture, integrity, and positioning relative to other stents. We present two illustrative cases of percutaneous coronary intervention utilizing a new ESI platform. The relevant literature is briefly reviewed.© 2013 Wiley Periodicals, Inc.     

Comparison between imported versus domestic drug‐eluting stents in China: A large single‐center data

Background

In recent years, most drug‐eluting stents (DESs) were domestically produced in China, but how domestic DESs perform compared to imported DESs was still unknown.

Methods

A total of 9011 consecutive cases with DESs implantation in a single center throughout 2013 were prospectively collected. Two‐year clinical outcomes were evaluated between patients implanted with imported and domestic DESs.

Results

During 2‐year follow‐up, the rates of all‐cause death, cardiac death, myocardial infarction, stroke, and stent thrombosis were not significantly different between two groups. However, the rate of revascularization was significantly higher in domestic DES group, shown as higher rates of overall revascularization, target vessel revascularization (TVR), and target lesion revascularization (TLR) (9.7% vs 6.4%, P < 0.001; 5.6% vs 3.2%, P < 0.001; 4.5% vs 2.2%, P < 0.001, respectively). Accordingly, major adverse cardiac events (MACE) rate was significantly higher in domestic DES group (12.1% vs 8.5%, P < 0.001). Multivariable Cox regression analysis indicated that domestic DES was an independent risk factor of MACE (HR [95%CI]: 1.22 [1.05‐1.41]), overall revascularization (HR [95%CI]: 1.29 [1.09‐1.53]), TVR (HR [95%CI]: 1.54 [1.22‐1.94]), and TLR (HR [95%CI]: 1.85 [1.41‐2.42]). After propensity score matching, the rates of overall revascularization, TVR, and TLR were still significantly higher in domestic DES group, and domestic DES was still predictive of overall revascularization, TVR, and TLR in multivariate Cox regression analysis.

Conclusions

Domestic DESs showed the same safety as imported DESs in this real‐world cohort. But, patients implanted with domestic DESs had a higher risk of revascularization than imported DESs.

     

Clinical and angiographic outcomes following elective implantation of the Carbostent in patients at high risk of restenosis and target vessel failure.

The Carbostent is a new balloon-expandable, stainless steel, tubular stent with innovative multicellular design and unique turbostratic carbon coating. The aim of this study was to assess clinical and angiographic outcomes after Carbostent implantation in 112 patients poorly suitable for an effective treatment with stenting because of the high risk of thrombosis, late restenosis, and clinical target vessel failure. The inclusion criteria were age > 75 years, diabetes mellitus, a lesion length > 10 mm, a reference vessel diameter < 3.0 mm, an ostial location of the target lesion, and chronic total occlusion. Overall, a total of 175 stents ranging from 9 to 25 mm in length were placed in 147 lesions. There were no stenting attempt failures. The acute gain after stent implantation was 2.46 +/- 0.51 mm, and the residual stenosis 0 +/- 4%. No stent thrombosis occurred, nor myocardial infarction. The 6-month event-free survival rate was 74% +/- 5%. The 6-month angiographic follow-up showed a late loss of 0.81 +/- 0.88 mm and a binary (> or = 50%) restenosis rate of 25%. The results of this study suggest that the Carbostent may be highly effective in patients at high risk of restenosis and target vessel failure.     

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。