光学相干断层成像和血管内超声在冠状动脉介入手术中的应用

目的 应用光学相干断层成像(OCT)及血管内超声(IVUS)检测技术评价冠状动脉内粥样硬化斑块的稳定性,并指导支架置入,检测血管对置入支架后即刻和中远期的反应.方法 选择2008年2-7月间的27例患者,进行冠状动脉造影、OCT及IVUS检查,共检查了30支血管,其中8处为药物支架植入术后血管,并对19处病变进行了支架置入.结果 除外支架置入的8例(置入6个月～4年)外,其余22例病变行OCT及IVUS检查,发现稳定性斑块5例,不稳定斑块17例,其中OCT检出内膜小撕裂4例(IVUS未检出,P＞0.05),冠状动脉撕裂伴夹层病变5例(IVUS检出1例,P＞0.05),血栓形成5例(IVUS检出1例,P＞0.05),偏心斑块伴薄纤维帽12例(IVUS检出2例,P＜0.01).8例曾经进行支架治疗的患者,造影、OCT和IVUS发现2例再狭窄;OCT显示支架内膜覆盖良好,IVUS小能精确看到内膜;OCT检测出1例患者有支架后瘤样扩张.对17例不稳定性斑块及2例支架再狭窄病例行支架置入术,术后支架膨胀不良发生率26.0%,OCT及IVUS检出率相同;支架贴壁不良发生率63.2%,IVUS榆出率低于OCT(10.5%比63.2%,P＜0.01);支架近远端撕裂10.5%,IVUS均不能检出;内膜脱垂发生率52.6%,IVUS检出率低于OCT(10.5%比52.6%,P＜0.05).结论 OCT与IVUS相比,在不稳定性斑块检测准确度方面明显优于IVUS,更能精确指导冠状动脉支架置人.IVUS在操作简便性及反映斑块负荷方面要优于OCT.     

OCT对冠状动脉介入术后即刻支架周围组织结构改变的评价

目的通过光学相干断层成像(OCT)初步评价冠状动脉内支架术后即刻支架周围组织结构特点。方法随机入选15例冠状动脉粥样硬化性心脏病(冠心病)行支架置入术患者,在患者置入支架后用OCT成像系统评价术后即刻支架释放情况及支架贴壁情况。结果15例患者共置入36枚支架,OCT检查得到满意图像并显示有14例患者冠状动脉内支架各部分充分释放,支架与血管壁贴合良好,无斑块组织向血管腔内突入,支架连接处贴合好;有1例患者支架部分节段释放不充分,支架与血管壁贴合不良,支架连接处贴合欠佳。结论OCT检查可充分评价支架释放及血管壁贴合和支架连接处管壁贴合情况,是检查支架术后支架周围组织结构的一种重要方法。     

光学相干断层成像在经皮冠状动脉介入治疗前后的应用

目的:探讨光学相干断层成像(OCT)在经皮冠状动脉介入治疗(PCI)前后应用的指导作用。方法:入选40例于我院行冠状动脉造影患者,根据罪犯血管狭窄程度分为两组:A组(狭窄程度≤75%,n=20)冠状动脉造影后行OCT检查,观察有无富含脂质斑块、薄帽纤维粥样斑块、斑块破裂、血栓,并测定病变狭窄程度;如需置入支架,则在术后即刻复查OCT,观察有无支架杆贴壁不良、血管夹层、组织脱垂等。B组(狭窄程度75%,n=20)仅在支架置入术后即刻行OCT检查。结果:A组20例患者的20支罪犯血管中,15支(75%)病变狭窄程度70%,其中3支为支架内再狭窄,6支血管发现斑块破裂,3支血管发现血栓形成,共发现富含脂质斑块22处、薄帽纤维粥样斑块9处(平均纤维帽厚度0.06 mm);共置入支架19枚,术后即刻行OCT检查,13枚支架(68.4%)可见不同程度的组织脱垂,平均最大组织脱垂面积为0.16±0.05(0.09~0.21)mm2,4枚支架(21.1%)中8个支架杆贴壁不良。B组20例患者的20支罪犯血管共置入34枚药物洗脱支架,术后即刻行OCT检查,有28枚支架(82.4%)存在不同程度的组织脱垂,平均最大组织脱垂面积为0.40±0.31(0.06~1.02)mm2。有9枚支架(26.5%)共20个支架杆贴壁不良。所有患者随访6个月以上,未发生严重心脏缺血事件。结论:OCT技术在支架术前可清晰显示冠状动脉结构、辨别不同斑块、斑块破裂及血栓,精确测量管腔狭窄程度。在支架术后可清晰显示血管夹层,组织脱垂及支架杆贴壁情况,可以指导及评价介入治疗。     

光学相干断层成像评价冠状动脉内支架术后即刻支架周围组织结构改变

目的:应用光学相干断层成像(OCT)评价冠状动脉内支架术后即刻支架周围组织结构改变。方法:对21例临床诊断冠心病准备介入治疗患者,在冠状动脉内置入支架后即刻进行OCT成像检查。21例患者中共有22支冠状动脉置入25个支架,其中前降支11支13个支架,回旋支8支9个支架,右冠状动脉3支3个支架。OCT评价支架贴壁不良、血管夹层及撕裂、组织脱垂等。支架贴壁不良定义为支架支撑杆与血管壁距离大于0.20mm,组织脱垂定义为血管壁组织通过支架网眼突入管腔。结果:21例患者均成功进行OCT检查,22支靶血管25个支架均成功获得清晰OCT图像。通过OCT发现置入的25个支架中有12个支架可以看到部分支架支撑杆未能完全封闭血管壁上的夹层及撕裂;所置入的支架中有50个支架支撑杆贴壁不良,平均支架支撑杆与血管壁的距离为0.39±0.20(0.20~1.16)mm。通过OCT检出置入的25个支架中有20个支架可见到不同程度组织脱垂,共检出85个组织脱垂,平均最大组织脱垂面积为0.55±0.64(0.04~2.81)mm2。结论:OCT成像技术可清晰显示冠心病冠状动脉支架后血管夹层、撕裂组织脱垂及支架贴壁情况,其临床意义有待于进一步研究。     

光学相干断层成像在冠状动脉临界病变介入诊断与治疗中的应用

目的评价光学相干断层成像(optical coherence tomography,OCT)在冠状动脉临界病变介入诊断与治疗中的可行性与有效性。方法在获得患者知情同意后,对来自15例患者的共16处冠状动脉造影结果显示狭窄程度(最小管腔直径/参照管腔直径)介于40%和70%之间的病变(即临界病变)行冠状动脉内OCT检查,评价病变狭窄程度、脂质核心大小、纤维帽的厚度、是否存在斑块破裂、是否伴有血栓形成以及斑块钙化程度。根据检查结果对伴随临床症状和心电图改变的易损斑块进行介入治疗。支架置入术后重复OCT检查,判断支架是否充分覆盖病变、与血管壁贴合情况,是否有斑块组织通过支架网眼突入管腔,以及局部是否存在微小夹层。结果入选的16处病变中的14处成功行OCT检查并获取满意图像。检查结果显示14处病变中有10处病变狭窄程度超过50%,并且脂质核心较大、纤维帽厚度小于65μm,判定以上10处病变为易损斑块,行冠状动脉内支架置入术。对其中2处伴有斑块破裂、局部形成夹层的病变行球囊预扩张后也行OCT检查,可见明显内膜撕裂、夹层形成。10处病变支架置入术后复查OCT显示支架均充分覆盖病变,其中2处支架与血管壁贴合不良,3处发生斑块组织明显突入管腔,有2处支架部分节段释放不充分。其余4处病变脂质核心较小,纤维帽厚度大于65μm,无斑块破裂表现,未行冠状动脉介入治疗。结论冠状动脉内OCT是一种判定冠状动脉病变特征的有效手段,对诊断易损斑块、制定经皮冠状动脉介入治疗策略以及评价支架置入术后即刻效果具有重要意义。     

冠状动脉支架内再狭窄的病理生理及治疗策略

冠状动脉支架内再狭窄严重影响冠心病支架置入患者预后,也是当前经皮冠状动脉介入术治疗领域亟待解决的问题。金属裸支架和药物洗脱支架置入术后支架内再狭窄的管理已经成为临床治疗的一种挑战。尸体解剖和血管内成像为支架内再狭窄的病理生理学研究提供了更多的可能。支架内再狭窄基本的治疗策略包括:球囊血管成形术、斑块切除术、血管内放疗、金属裸支架置入、药物涂层球囊、药物洗脱支架置入。最有效的治疗方法取决于患者和病变特点,药物洗脱支架和药物涂层球囊的问世成为冠心病介入治疗(经皮冠状动脉介入术)技术突破的历史性转折点。现主要讨论支架内再狭窄的病理生理、危险因素及治疗策略。     

第二代药物洗脱支架

自2002年药物洗脱支架被引入以来,该类支架已经在冠状动脉介入治疗中获广泛应用。药物洗脱支架就是在金属裸支架的表面涂以包含抗增殖剂的聚合物。这种聚合物能在支架置入后的数周至数月内持续释放并持续抑制血管内膜增生。第一代药物洗脱支架主要是西罗莫司和紫杉醇支架,相对于金属裸支架和单纯球囊扩张,它在减少支架内再狭窄和再次介入方面显示了优势。     

光学相干断层成像技术在冠心病介入诊疗中的优势与前景

自2002年美国麻省总医院Jang等[1]]将光学相干断层成像(optical coherence tomography,OCT)应用于冠心病介入领域以来,OCT作为一种革命性的冠状动脉内成像技术,提供了前所未有的高分辨率(10 μm),不仅能够清晰的观察动脉粥样硬化斑块的构成和形态,而且对于应用经典的血管内超声和血管镜都无法判断的支架的贴壁和支架术后内膜再生情况,OCT都可以清楚地分辨和评价,使得人们对冠状动脉粥样硬化斑块和介入治疗后血管内膜修复愈合的认识都更加深入.随着科技的进步,OCT技术也在不断更新换代,本文就OCT技术的原理、特点及临床应用作一论述.     

血管内超声和光学相干断层成像在冠状动脉介入治疗中的应用价值

冠状动脉(冠脉)造影仅能提供血管腔的影像,不能反应血管壁和粥样硬化斑块本身的信息,血管内超声(IVUS)和光学相干断层成像(OCT)则可补充之,获得连续血管横断面图像,对斑块进行定性定量分析,识别易损斑块,判断临界病变的严重程度,指导冠脉介入治疗(PCI),并观察支架扩张、贴壁和内膜修复及增生情况,发现晚期支架贴壁不良和断裂等.应用IVUS和OCT指导PCI可显著降低心血管不良事件的发生.两者主要区别在于分辨率相差10倍,IVUS成像较模糊,而OCT更清晰,两者合一、互相补充是发展方向.     

冠状动脉分叉病变处置入药物洗脱支架的系列技术探讨

药物洗脱支架可显著减少冠状动脉分叉处支架置入术后的再狭窄。其再狭窄往往与支架贴壁不良、缠绕扭曲有关。本研究探讨了不同方法的药物洗脱支架置入技术及其效果,显示对吻支架术加球囊后扩张技术可更好地覆盖病变。研究在离体模型中进行,选用金属裸支架,使用不同的洗脱支架置     

抗CD34抗体优化雷帕霉素洗脱支架疗效的实验研究

目的 评价抗CD34抗体对雷帕霉素洗脱支架早期再内皮化以及远期抗再狭窄的影响.方法 将裸金属支架(BMS)、雷帕霉素洗脱支架(SES)和抗CD34抗体与雷帕霉素洗脱联合支架(ASES)随机置入到22头中华小型猪的冠状动脉内(共置入15枚BMS、17枚SES和16枚ASES).10头中华小型猪在置入支架(共置入6枚BMS、7枚SES和7枚ASES)后2周,另外12头中华小型猪在置入支架(共置入9枚BMS、10枚SES和9枚ASES)后3个月,进行冠状动脉造影及冠状动脉内光学相干断层成像( OCT)检查,并在处死动物后对支架段冠状动脉进行病理组织学检查及扫描电镜观察.结果 (1)支架术后2周,冠状动脉造影、OCT图像及支架段冠状动脉的病理组织学的观察均未发现支架内血栓及小的附壁血栓.对OCT图像的分析显示,ASES新生内膜覆盖率显著高于SES[ (55.56±35.27)％比(41.82±23.28)％,P＜0.05];ASES平均内膜覆盖厚度不但显著高于SES[(89.0±5.0)μm比(32.0±4.9) μm,P＜0.01],而且显著高于BMS[( 89.0±5.0) μ,m比(44.0±7.2)μm,P＜0.01].病理组织学观察及扫描电镜观察显示,ASES和BMS新生内膜覆盖水平及质量均优于SES.(2)支架术后3个月,定量冠状动脉造影显示ASES晚期支架内管腔丢失显著低于BMS [(0.18±0.06)mm比(0.35±0.06)mm,P＜0.05];对OCT图像的分析显示,ASES和SES新生内膜增生百分比均显著低于BMS[ (34.75±2.64)％和(35.63±2.07)％比(48.28±3.25)％,均P＜0.01];组织病理学分析显示,ASES和SES面积再狭窄百分比均显著低于BMS组[(28.65±5.64)％和(29.33±6.07)％比(46.18±8.25)％,均P＜0.05].结论 将抗CD34抗体联合应用到雷帕霉素洗脱支架上能够显著抵消后者在支架术后2周对再内皮化的抑制作用,同时没有削弱雷帕霉素洗脱支架术后3个月的抗再狭窄效能.     

Incomplete neointimal coverage of sirolimus-eluting stents: angioscopic findings.

OBJECTIVES: The goal of this study was to use angioscopy to investigate the amount of neointimal coverage after sirolimus-eluting stent (SES) implantation. BACKGROUND: Sirolimus-eluting stents reduce intimal hyperplasia. METHODS: We used angioscopy to evaluate 37 consecutive stented coronary artery lesions (15 SES and 22 bare-metal stents [BMS]) in 25 patients (18 men, 7 women) at 3 to 6 months after stent implantation. Angioscopic evaluation focused on: 1) neointimal coverage of stent struts, and 2) the existence of thrombi. The degree of neointimal coverage was classified as grade 0 when there was no neointimal coverage (similar to immediately after the implantation); grade 1 when stent struts bulged into the lumen, but were covered and still translucently visible; grade 2 when stent struts were visible but not clearly seen (not translucent); and grade 3 when stent struts were not visible because they were embedded in the neointima. RESULTS: Thrombi were identified in eight stented segments, tended to be more common with SES (p = 0.14), but were not seen on angiography. Three of the 15 SES (20%) had grade 0 neointimal coverage, and only 2 SES (13.3%) had complete coverage (grades 2/3). In contrast, all 22 BMS showed complete intimal coverage (grades 2/3). Thrombi were more common in stents with incomplete neointimal coverage (p = 0.09). CONCLUSIONS: The SES had incomplete neointimal coverage three to six months after implantation, and this was associated with subclinical thrombus formation.     

In-stent restenosis in bare metal stents versus sirolimus-eluting stents after primary coronary intervention for acute myocardial infarction and subsequent transcoronary transplantation of autologous stem cells

BACKGROUND: Following stenting for acute myocardial infarction, transcoronary transplantation of granulocyte-colony stimulating factor (G-CSF) mobilized autologous stem cells (ASC) has been shown to result in an increased in-stent restenosis rate of bare metal stents (BMS). HYPOTHESIS: This study sought to compare the extent of neointimal growth in BMS and sirolimus-eluting stents (SES) after primary implantation, and subsequent transcoronary transplantation of G-CSF mobilized stem cells. METHODS: Patients with stenting of the left anterior descending coronary artery for acute anterior myocardial infarction were randomly assigned to receive a BMS or SES. Intracoronary stem cell injection was performed after G-CSF application for at least 4 d and cell apheresis. The angiograms obtained after cell transplantation and after 6 mo were analyzed by quantitative coronary angiography. RESULTS: We performed primary stenting and stem cell transplantion in 16 patients who received a BMS (n = 8) or an SES (n = 8). In 2 patients with a BMS, late stent thrombosis occurred after 58 d and 177 d, respectively. In the remaining patients, control angiography after 6 mo revealed in-stent restenosis of >50% in no patients with SES but in 4 patients with BMS (67%). Late lumen loss and in-stent plaque volume were significantly higher in patients with BMS compared with patients with SES. CONCLUSIONS: Compared with BMS, SES impair in-stent intima hyperplasia after stenting for acute myocardial infarction and transcoronary transplantation of G-CSF mobilized ASC. Copyright (c) 2008 Wiley Periodicals, Inc.     

Difference in neointimal coverage at chronic stage between bare metal stent and sirolimus-eluting stent evaluated at stent-strut level by optical coherence tomography

Compared with the bare metal stent (BMS), suppression of neointimal growth in the sirolimus-eluting stent (SES) reduced restenosis at the cost of more exposed struts that could impose the risk of stent thrombosis. The present study was conducted to analyze neointimal coverage patterns of stents at a strut-level after implantation of BMS or SES with the use of optical coherence tomography (OCT). We enrolled 35 patients and analyzed neointimal coverage of every strut from 41 stents (BMS: n = 8, SES: n = 33) by using OCT at follow-up of the stent implantation. All of the 371 struts from eight BMSs were covered with ≥100 μm of neointima, while 19.8 and 3.5 % of 3,478 struts from 33 SESs were uncovered (neointimal thickness of <10 μm) and malapposed, respectively. The histogram of neointimal thickness showed basically normal distribution in BMS but skewed in SES. No regional difference in neointimal thickness was observed in BMS (proximal, 535.7 ± 25.2 μm; body, 532.4 ± 17.0 μm; distal, 485.8 ± 27.0 μm). In SES, however, the body segment showed thinner neointima [median 40 μm (interquartile range (IQR) 10–90 μm)] than proximal [60 μm (IQR 10–140 μm), p < 0.001] or distal [50 μm (IQR 10–110 μm), p < 0.001] segment, while uncovered and malapposed struts were more frequent in the proximal and body segments. In conclusion, SES, compared with BMS, showed more suppressed neointimal growth with regional variation: neointimal thickness was the least in the body part while the ratio of exposed and malapposed struts was minimal in the distal segment. OCT was useful for a strut-level analysis of neointimal coverage over the whole stent.     

The wound healing response after implantation of a drug-eluting stent is impaired persistently in the long term

A 70-year-old man underwent stent implantation for right coronary artery (RCA) lesions with a bare metal stent (BMS) and two sirolimus-eluting stents (SES). However, as both the BMS and SES stented sites developed restenosis after 13 months, he underwent target lesion revascularization using directional coronary atherectomy (DCA). On histopathology, the restenosis lesion at the SES-deployed site showed greater inflammation and less re-endothelialization than that at the BMS-deployed site. Three months later, the SES-deployed site developed a second restenosis, in which paclitaxel-eluting stents (PES) were implanted (PES-in-SES), while the BMS-deployed site was restenosis free. Five years later, restenosis was absent in these RCA lesions. However, by optical coherence tomography and/or coronary angioscopy, the PES-in-SES site in the RCA showed poor neointimal coverage over the stent struts and yellowish neointima, suggesting lipid-rich neoatheroma formation, whereas at the BMS site appropriate white neointima formation was observed. Drug-eluting stents still have problems of persistent inflammation, inappropriate neointima formation, and neoatherosclerosis. Although we are now in the era of second generation DESs in which better stent performance would be promising, we should remember that we are obliged to continue to follow-up all patients in whom first generation DESs such as SES or PES have been placed.     

Outcome of percutaneous hybrid coronary revascularization: bare metal stents jeopardize the benefit of sirolimus-eluting stents in the real world

BACKGROUND: In an effort to contain procedural costs while limiting the risk of in-stent restenosis, hybrid percutaneous revascularization (ie, stenting with at least one sirolimus-eluting stent [SES] and at least one bare metal stent [BMS] in the same patient) is felt to be a cost-effective alternative to exclusive SES use. OBJECTIVE: To describe the outcome of hybrid percutaneous revascularization for the treatment of patients with multiple coronary artery lesions. METHODS AND RESULTS: Fifty-six patients (42 men; mean age [+/- SEM] 64+/-2) underwent hybrid stenting (average of 1.2 SES/patient and 1.3 BMS/patient). SES were used to treat lesions at higher restenotic potential, including longer lesions, smaller target vessels and bifurcation lesions (mean stent length [+/- SEM] was 21.1+/-1.2 mm for SES and 16.0+/-0.6 mm for BMS; stent diameter mean [+/- SEM] was 2.9+/-0.0 mm for SES and 3.1+/-0.1 mm for BMS; bifurcation lesions were 43% for SES and 7% for BMS; all P<0.01). At nine months of clinical follow-up, no death or myocardial infarction was reported. Twenty-one patients underwent clinically driven repeat coronary angiography at a mean (+/- SEM) of 8+/-1 of months (range two to 12 months) follow-up. Target lesion revascularization procedures were recorded in six patients (11%) for nine lesions (6%). Of these lesions, seven were categorized after blinded analysis as due to in-BMS restenosis and two to in-SES restenosis (P=0.01); three patients (5.4%) underwent reangioplasty for de novo lesions. There was one case of acute in-SES thrombosis. SES showed significantly less neointimal hyperplasia (late lumen loss was 0.4+/-0.1 mm for SES and 1.3+/-0.1 mm for BMS; loss index was 0.15+/-0.05 for SES and 0.48+/-0.05 for BMS; all P<0.001). CONCLUSIONS: The use of SES resulted in less neointimal hyperplasia even when used to treat lesions at higher risk for restenosis based on angiographic characteristics. BMS implantation significantly limits this beneficial effect, compromising the outcome of hybrid percutaneous coronary revascularization.     

The union of anti-CD34 antibody can improve the performance of drug-eluting stents

Objectives : The authors investigate whether the combination of anti‐CD34 antibody with DES is win–win cooperation. Background : DES may reduce the risk of restenosis compared to bare‐metal stents (BMS), but they were found to inhibit the healing process of intima. Methods : Fifteen BMS, 17 DES, and 16 combined anti‐CD34 antibody and DES were randomly implanted in the coronary arteries of 22 minipigs. Ten minipigs were followed up to 2 weeks. The stenting coronary segments were examined by histological examination and scanning electron microscopy after in vivo coronary angiography and intracoronary optical coherence tomography (OCT) examinations. The other 12 minipigs were followed up to 3 months. Coronary angiography and intracoronary OCT examination were performed in vivo and histological examination was performed on the stenting coronary segments. Results : After 2 weeks, the neointimal covering level of the DES was lower than that in BMS, but the covering level of the combined stents was even better than the BMS. After 3 months, neointimal hyperplasia was significant in the BMS, but not in the other two types of stents. The in‐stent late lumen loss of the combined stents even showed a decreasing tendency when compared with the DES. Conclusion : The combination of anti‐CD34 antibody and DES can not only well offset the short‐term inhibitory effect on re‐endothelialization but also slightly enhance the long‐term antiproliferative effect. © 2011 Wiley Periodicals, Inc.     

Comparison of angioscopic findings and three-year cardiac events between sirolimus-eluting stent and bare-metal stent in acute myocardial infarction

The safety of sirolimus-eluting stents (SESs) in acute myocardial infarction (AMI) remains controversial. We compared long-term neointimal coverage after stent implantation for AMI evaluated by coronary angioscopy and 3-year clinical events between SESs and bare-metal stents (BMSs). Eighty-seven consecutive patients who received SESs or BMSs for AMI were enrolled. At 8 months after AMI coronary angiography with angioscopy was performed. Using angioscopy we evaluated maximum and minimum grades of neointimal coverage using an angioscopic score (0 to 3). We calculated the heterogeneity score as the maximum grade minus the minimum grade. We compared angioscopic parameters including minimum grade and heterogeneity score of neointimal coverage, thrombi and plaque color, serum parameters, and major adverse cardiac events for 3 years between the 2 groups. The restenosis rate of the SES group (n = 56) was significantly lower than that of the BMS group (n = 31, 9% vs 31%, p = 0.015). The SES group had a lower minimum grade of neointimal coverage and higher heterogeneity score and prevalence of thrombi than the BMS group, but from 8 months to 3 years after stent implantation there were no significant differences in major adverse cardiac events between the 2 groups. In conclusion, a lower minimum grade and greater heterogeneity of neointimal coverage and thrombi were shown for SESs compared to BMSs at 8 months after AMI. However, these findings did not correlate with cardiac events over a period of 3 years in our patients.