Preliminary Clinical Outcomes after Implantation of Newer-Generation Biodegradable Polymer-Coated Everolimus-Eluting Stent in “Real-World” Patients with Coronary Artery Disease

Background and Objective: In the contemporary practice, the use of drug-eluting stents is still associated with low mortality benefits, restenosis and stent thrombosis. To address these issues, newer generation, thin-strut, biodegradable polymer coated stents has been designed. Thus, the aim of the study is to assess the safety and clinical performance of the Everoflex (Sahajanand Medical Technologies Pvt. Ltd., Surat, India), a newer generation biodegradable polymer coated everolimus-eluting stent, in unselected “real-world” patients with coronary artery disease. Methods: It is a multicentre, retrospective, non-randomized, single-arm study enrolling all the consecutive patients who underwent implantation with the Everoflex for coronary artery disease from April 2014 to March 2016. The primary end-point of the study is 30-day major adverse cardiovascular events (MACE) rate, which consists of cardiac death, myocardial infarction, target lesion revascularization and target vessel revascularization. Stent thrombosis was also analyzed and reported. Results: A total of 340 patients were intervened successfully with 395 everolimus eluting stents (1.3 ± 0.6 stents per patient). Out of total patients (58.7 ± 10.5 years), 77.9% were male and comorbidities like diabetes and hypertension were observed in 31.2% and 35.3% patients, respectively. According to ACC/AHA classification, there were 34.4% type B lesions and 53.2% type C lesions, indicating a higher proportion of complexity involved. Moreover, 57.9% patients had multivessel disease and there were 15.4% total occlusions. At 30 days, follow-up was completed in 100% patients. The MACE was found to be 1.5%, which is a composite of 1.2% cardiac death and 0.3% target lesion revascularization. Stent thrombosis at 30 days was found to be 0.3%. Conclusion: The low incidence of MACE and stent thrombosis clearly depicts excellent safety and clinical performance of the Everoflex in unselected real world patients with coronary artery disease.

Advantages and disadvantages of biodegradable platforms in drug eluting stents

Coronary angioplasty with drug-eluting stent(DES)implantation is currently the most common stent procedure worldwide.Since the introduction of DES,coronary restenosis as well as the incidence of target vessel and target lesion revascularization have been significantly reduced.However,the incidence of very late stent thrombosis beyond the first year after stent deployment has more commonly been linked to DES than to baremetal stent(BMS)implantation.Several factors have been associated with very late stent thrombosis after DES implantation,such as delayed healing,inflammation,stent mal-apposition and endothelial dysfunction. Some of these adverse events were associated with the presence of durable polymers,which were essential to allow the elution of the immunosuppressive drug in the first DES designs.The introduction of erodable polymers in DES technology has provided the potential to complete the degradation of the polymer simultaneously or immediately after the release of the immunosuppressive drug,after which a BMS remains in place.Several DES designs with biodegradable(BIO)polymers have been introduced in preclinical and clinical studies, including randomized trials.In this review,we analyze the clinical results from 6 observational and randomized studies with BIO polymers and discuss advantages and disadvantages of this new technology.

Safety and Efficacy of Ultra-Thin, Biodegradable Polymer Coated Sirolimus-Eluting Supralimus-Core Stents in Real-World Patients: Outcomes at 24-Month Follow-Up

Aim: The purpose of this registry was to establish long-term safety and efficacy through implantation of Supralimus-Core sirolimus-eluting stents (SES) in real-world patients with coronary artery disease (CAD). Methods:The present registry was a retrospective, singe-arm, single-centre, investigator-initiated registry. A total of 372 consecutive patients were implanted with Supralimus-Core SES between January 2015 and November 2016. The primary endpoints were major adverse cardiac events (MACE), a composite of cardiac death, myocardial infarction (MI), target lesion revascularization (TLR) and target vessel revascularization (TVR) at 24 months. The secondary endpoints were all-cause death and all separate components of the primary endpoint. Additional endpoints included events of stent thrombosis classified as definite, probable, and possible stent thrombosis. Follow-ups were conducted at 30-days, 6-months, 12-months and 24-months after the index procedure. Results: The mean age of the registry population was 56.3 ± 11.1 years. Males constituted 276 (74.2%) patients. Hypertensives, diabetics, alcoholics, tobacco chewers and smokers comprised 198 (53.2%), 160 (43.0%), 93 (25.0%), 91 (24.5%) and 88 (23.7%) of the registry population, respectively. The mean length and diameter of stents implanted was 19.3 ± 8.8 mm and 2.9 ± 0.3 mm, respectively. At the 24-month follow-up, MACE was reported in 14 (3.8%) patients. Cardiac death, MI, TLR and TVR was reported in 7 (1.9%), 4 (1.1%), 3 (0.8%) and 4 (1.1%) patients, respectively. Overall stent thrombosis occurred in 4 (1.1%) patients. Conclusions: The low MACE rate of 3.8% at the 24-month follow-up indicates favorable long-term results after implantation of the ultra-thin strut Supralimus-Core SES in all-comer, real-world patients.

A novel polymer-free dual-drug eluting stent with nanotechonology

Durable polymers used for first-generation drug-eluting stents potentially contribute to persistent inflammation and late stent thrombosis. BICARE （Lepu Medical Technology Co., Ltd, Beijing, China） is a novel polymer-free stent system with nanotechnology and elutes rapamycin （1.6 μg/mm2） and probucol （0.8 μg/mm2）. The millpores on the surface of the stents were produced by nanotechnology. Studies on in-vitro release profile and the preliminary feasibility and safety of the BICARE stent were conducted. The results of release profile study demonstrated the ability of dual-drug polymer-free loading stents to release rapamycin and probucol in a controlled and sustained manner. The preliminary feasibility and safety of BICARE dual-drug polymer-free stent are demonstrated firstly in human study. Optical coherence tomography （OCT） findings indicated excellent stent strut coverage at 4-month. Further pivotal randomized trial will confirm if this early results could translate into longer term safety and efficacy benefits.

A comparison of clinical and angiographic outcomes after Excel bioabsorbable polymer versus Firebird durable polymer rapamycin-eluting stent for the treatment of coronary artery disease in a “real world” setting:six-month follow-up results

Background Several clinical trials have shown that rapamycin-eluting stents significantly reduce the risk of restenosis after percutaneous coronary intervention （PCI）. The Firebird stent and the Excel stent （coated with bioabsorbable polymer） are two different types of rapamycin-eluUng stents made in China, both have been recently approved for clinical use in China by State Food and Drug Administration. However, it is unclear whether there are differences in safety and efficacy between the two types of stents in daily practice. Methods In the month of June 2006, a total of 190 consecutive patients were treated exclusively with Firebird stents （n=93, Firebird group） or Excel stents （n=97, Excel group） in our center and were included in this study. The frequency of major adverse cardiac events （MACE, a composite of death, myocardial infarction or target lesion revascularization）, binary restenosis, and late lumen loss and stent thrombosis dudng a six-month follow-up period were compared between the two groups. Results Patient and lesion characteristics were comparable between the groups. Major adverse cardiac event rates were low in hospital and at 6 months （2.1% in the Excel group and 0% in the Firebird group, P〉 0.05）. The 6-month angiographic in-stent restenosis rate was 0% in both groups, with an associated late loss of （0.15 ± 0.21） mm versus （0.14 ± 0.20） mm （P=0.858） and the in-segment restenosis rate was also 0% for the Excel group and the Firebird group. There was no definite stent thrombosis identified in either group during the six-month follow-up period and only one patient in the Excel group had probable stent thrombosis in hospital. Conclusions Results from this mid-term, single-center study showed that both of the Firebird and the Excel rapamycin eluUng stent had similar effects on reducing the incidence of MACE and the risk of restenosis （both in-stent and in-segment binary restenosis） after PCI in daily practice.

Long-term clinical outcomes after bioabsorbable polymer- and durable polymer-based sirolimus-eluting stents implantation： two-year follow-up results from a large single-center database

Background Several clinical trials have shown that sirolimus-eluting stents significantly reduce the risk of restenosis after percutaneous coronary intervention （PCI）. The FIREBIRD stent （coated with durable polymer） and the EXCEL stent （coated with bioabsorbable polymer） are two different types of sirolimus-eluting stents made in China; both have been approved for clinical use in China by the State Food and Drug Administration. The mid-term （6-month） angiographic and clinical results of both stents have been confirmed exciting perspective outcomes. However, it is unclear whether there are differences in the long-term safety and efficacy between the two types of stents in daily practice.Methods All consecutive patients undergoing elective PCI with EXCEL or FIREBIRD stents between June 1,2006 and December 31, 2006 at Fu Wai Hospital in Beijing were included. Patients were classified from the index admission according to stent types （EXCEL or FIREBIRD） used. Clinical and procedural risk factors were collected prospectively. With propensity score matching without replacement, the frequency of major adverse cardiac events （MACE, a composite of death, myocardial infarction or target vessel revascularization） and stent thrombosis during a 2-year follow-up period were compared between the two groups.Results A total of 474 patients were treated with EXCEL, and 640 were treated with FIREBIRD. Three hundred and ninety-seven EXCEL patients were matched to 397 FIREBIRD patients, 2-year risk-adjusted MACE rates were 6.1% in EXCEL group and 7.6% in FIREBIRD group （HR 0.84, 95%CI0.50-1.43）, whereas the respective rates for mortality, myocardial infarction and target-vessel revascularization were 2.3% vs 2.8% （HR 0.74, 95%CI0.30-0.85）, 1.8% vs 1.3% （HR 1.41,95%CI 0.45-4.43） and 2.5% vs 4.0% （HR 0.62, 95%CI0.28-0.37）, respectively. Cumulative incidence of stent thrombosis at 2 years was 1.8% in the EXCEL group vs 1.3% in the FIREBIRD group （P=0.5610）, whereas the rate of very late stent thrombosis was 0.5% vs 1.3% （P=0.2550）.Conclusions Results from this long-term, relatively large size, single-center study showed that both of the EXCEL and the FIREBIRD sirolimus-eluting stent had similar and lower incidence of MACE after PCI in daily practice.

Novel completed biodegradable polymer sirolimus-eluting stent versus durable polymer sirolimus-eluting stent in de novo lesions： nine-month angiographic and three-year clinical outcomes of HOPE trial

Background Drug-eluting stents（DES） with durable polymer have significantly reduced restenosis and target vessel revascularization compared with bare metal stents. Durable polymer has been linked with persistent inflammation of vessel wall and delayed endothelial healing that may increase the risk of late and very late stent thrombosis. This study sought to evaluate the efficacy and safety of HELLOS completed biodegradable polymer sirolimus-eluting stent （SES） in de novo coronary lesions.Methods Totally, 287 patients with one or two de novo coronary lesions （lesion length ≤38 mm and reference vessel diameter 2.5-4.0 mm） were enrolled in the HOPE study, a prospective, multicenter, randomized, non-inferiority trial. Patients were randomized to treatment either with HELIOS completed biodegradable polymer SES （n=142） or PARTNER durable polymer SES （n=145）. The primary endpoint was angiographic in-stent late lumen loss （LLL） at 9-month follow-up. The secondary endpoint included stent thrombosis and major adverse cardiac events including cardiac death, myocardial infarction （MI） and target lesion revascularization （TLR）.Results The 9-month in-stent LLL in the HELIOS group was similar to the PARTNER group, （0.16±0.22） mm vs. （0.19±0.30） mm （P=0.28）. The difference and 95% confidence interval were -0.03 （-0.09, 0.04）, and the P value for non-inferiority 〈0.01. Major adverse cardiovascular event （MACE） occurred in 7.9% vs. 8.2%, MI in 2.4% vs. 3.0%, TLR in 5.5% vs. 3.0%, and stent thrombosis in 0 vs. 1.5%; and events were comparable between the HELIOS group and PARTNER aroup at three-year follow-up （all P 〉0.05）. The three-year cardiac death was lower in the HELIOS group, butwith no significant difference, 0 vs. 3.0% （P=0.12）. Conclusions In the HOPE trial, the novel completed biodegradable polymer SES HELIOS was non-inferior to the durable polymer SES PARTNER with respect to nine-month in-stent LLL in de novo coronary lesions. The incidence of other clinical endpoints was low for both of the stents in three-year follow-up.

Comparison the long-term clinical outcomes of Nano polymer-free sirolimus-eluting stent versus Endeavor durable polymer zotarolimus-eluting stent in patients with acute coronary syndrome

Background Durable polymer drug eluting stent （DES） is confronted with many issues, especially the inci- dence of late stent thrombosis （ST） which is mainly due to delayed healing and re-endothelization by the durable polymer coating. Newer polymer-free DES might have a reduction in late stent thrombosis. Therefore, the aim of this study was to evaluate the efficacy and safety of two different drug eluting stents in patients with acute coro- nary syndromes （ACS） by one year follow-up. Methods This study assessed the results of the Nano polymer- free SES （Lepu Medical Technology, Beijing, China） and Endeavor durable-polymer ZES （Medtronic, Minneapo- lis, MN, USA） in ACS patients by clinical follow-up and coronary angiography analysis. The primary endpoint was the onset of any major adverse cardiac events （MACE） such as cardiac death, myocardial infarction （MI） and target vessel revascularization （TVR）. The secondary endpoints were target lesion revascularization （TLR） and stent thrombosis （ST） at the end of one year follow-up. Results Between April 2014 and June 2015, a total of 513 consecutive patients were enrolled in this trial. There were 259 patients enrolled in Nano group and 253 pa- tients in Endeavor group. Mean age was 62.8 ＋10.3 years old （range： 28 to 87 years of age）, and 65.3% of pa- tients were male. Compared Nano-SES to Endeavor-ZES, the incidence of MACE was 5.4% vs. 7.1%. The hazard ratio （HR） was 1.32 with 95% confidence interval （CI） as 0.64-2.72 （P = 0.45）. Secondary end points showed TLR （1.9% vs. 3.2%; HR, 1.42; 95% CI, 0.45-4.55; P = 0.55） and ST （0.4% vs. 0.8%; HR, 2.03; 95% CI, 0.18- 5.37; P = 0.99）, in the one-year period of follow-up. Conclusion Within one-year, the Nano polymer-free SES has similar safety and efficacy compared with the Endeavor durable-polymer ZES in the treatment of patients with ACS.

Safety and efficacy of cobalt chromium alloy based sirolimus-eluting stent with bioabsorbable polymer in porcine model

Background First generation drug-eluting stents （DESs） were based on 316L stainless steel and coated with a permanent polymer. The vessel wall of these DESs was inflammatory and late in-stent thrombosis was reported. Hence, cobalt chromium based DES coated with a bioabsorbable polymer was an alternate choice. Methods Cobalt chromium based DES with bioabsorbable polymer （Simrex stent） as well as control stents （Polymer stent and EXCELTM stent） were implanted into porcine arteries. At a designated time, angiography, quantitative coronary angiography （QCA） analysis, histomorphometry, and electron-microscopical follow-up were performed. Results A total of 98 stents of all the three groups were harvested. At week 24, percent diameter stenosis （%DS）, late loss （LL）, and percent area stenosis （%AS） of Simrex was （12.9±0.4）%, （0.35±0.02） mm, and （24.5±4.2）%, respectively, without significant difference in comparison to commercialized EXCELTM stent. Slight inflammatory reaction was seen around the stent strut of Simrex, just as in the other two groups. Electron-microscopical follow-up suggested that it might take 4-12 weeks for Simrex to complete its re-endothelialization process. Conclusions Cobalt chromium based, bioabsorbable polymer coated sirolimus-eluting stent showed excellent biocompatibility. During 24 weeks observation in porcine model, it was proved that this novel DES system successfully inhibited neointima hyperplasia and decreased in-stent stenosis. It is feasible to launch a clinical evaluation to improve the current prognosis of DES implantation.

Long-term effects of biodegradable versus durable polymer-coated sirolimus-eluting stents on coronary arterial wall morphology assessed by virtual histology intravascular ultrasound

Background The durable presence of polymer coating on drug-eluting stent （DES） surface may be one of the principal reasons for stent thrombosis. The long-term coronary arterial response to biodegradable polymer-coated sirolimus-eluting stent （BSES） in vivo remained unclear.Methods Forty-one patients were enrolled in this study and virtual histology intravascular ultrasound （VH-IVUS） was performed to assess the native artery vascular responses to BSES compared with durable polymer-coated SES （DSES） during long-term follow-up （median： 8 months）. The incidence of necrotic core abutting to the lumen was evaluated at follow-up.Results With similar in-stent late luminal loss （0.15 mm （0.06-0.30 mm） vs. 0.19 mm （0.03-0.30 mm）, P=0.772）, the overall incidence of necrotic core abutting to the lumen was significantly less in BSES group than in DSES group （44% vs.63%, P 〈0.05） （proximal 18%, stented site 14% and distal 12% in BSES group, proximal 19%, stented site 28% and distal 16% in DSES group）. The DSES-treated segments had a significant higher incidence of necrotic core abutting to the lumen through the stent struts （73% vs. 36%, P 〈0.01）. In addition, more multiple necrotic core abutting to the lumen was observed in DSES group （overall： 63% vs. 36%, P 〈0.05）. Furthermore, when the stented segments with necrotic core abutting to the lumen had been taken into account only, DSES-treated lesions tended to contain more multiple necrotic core abutting to the lumen through the stent struts than BSES-treated lesions （74% vs. 33%）, although there was no statistically significant difference between them （P=0.06）.Conclusions By VH-IVUS analysis at follow-up, a greater frequency of stable lesion morphometry was shown in lesions treated with BSESs compared with lesions treated with DSESs. The major reason was BSES produced less toxicity to the arterial wall and facilitated neointimal healing as a result of polymer coating on DES surface biodegraded as time went by.

Long Coronary Lesions: Challenging Cases for Percutaneous Coronary Intervention

Long coronary lesions are associated with adverse outcomes after percutaneous coronary intervention since the era of plain balloon angioplasty. Long lesion and long stent length are considered as important predictors of restenosis after percutaneous coronary intervention. With the advent of newer generation drug eluting stents, there has been dramatic reduction in the rates of restenosis and repeat revascularization, even in complex cohort of patients with long coronary lesions. We report one such case of long coronary lesion which was intervened successfully with newer generation, thin strut, biodegradable polymer coated sirolimus-eluting stents.

新型生物可降解聚合物雷帕霉素靶向洗脱支架预防支架内狭窄的动物实验研究

目的:评价新型的生物可降解聚合物雷帕霉素靶向洗脱支架—Firehawk在小型猪冠状动脉模型预防支架内狭窄的疗效。方法:将Firehawk支架(Firehawk组,n=10)和采用永久聚合物涂层雷帕霉素洗脱支架Firebird 2(Firebird 2组,n=8)置入健康小型猪冠状动脉。术后4周时测定两组支架血管段的平均内膜厚度、新生内膜面积、面积狭窄百分比等参数,以比较其内膜增生的情况。结果:术后4周,Firehawk组和Firebird 2组平均内膜厚度分别为(0.15±0.10)mm和(0.14±0.06)mm,新生内膜面积分别为(1.12±0.57)mm2和(1.04±0.36)mm2,面积狭窄百分比分别为(24.58±14.85)%和(26.80±10.64)%,差异均无统计学意义(P均>0.05)。两组均无支架内狭窄发生。结论:Firehawk支架可有效抑制支架置入后4周时的内膜增生,预防冠状动脉实验性支架内狭窄,效果与传统的永久聚合物涂层药物洗脱支架相当。长期效果有待进一步观察。

可降解与非降解聚合物涂层雷帕霉素洗脱支架置入小型猪冠状动脉后的对比研究

目的:对比4种不同的生物可降解或非降解聚合物涂层的雷帕霉素洗脱支架(SES)置入健康小型猪冠状动脉后的安全性及有效性。方法:对2007-09至2009-07期间本研究组完成的采用4种不同涂层SES的动物实验资料进行分析,分为可降解的聚乳酸聚羟基乙酸共聚物(PLGA)涂层SES组(PLGA组)、可降解的聚左旋乳酸(PLLA)涂层SES组(PLLA组)、非降解的苯乙烯丁烯嵌段共聚物(SBS)涂层SES组(SBS组)和非降解的聚乙烯醋酸乙烯酯(EVAC)涂层SES组(EVAC组)。PLGA组包括4周观察终点的猪5只,另外3组包括4周观察终点的猪各4只。每只猪于左前降支和右冠状动脉各置入同种支架1枚。至观察终点时复查冠状动脉造影并处死取材,通过形态学方法观察血管壁炎症及内膜增生情况。结果:4周时EVAC组有3例标本血管壁大量淋巴细胞和嗜酸细胞浸润,形成炎症肉芽肿,而PLGA组、PLLA组和SBS组无明显炎症反应。PLGA组、PLLA组和SBS组平均炎症细胞密度,残余管腔直径,残余管腔面积,内弹力板围绕面积,外弹力板围绕面积均显著小于EVAC组,差异有统计学意义(P均<0.05),而PLGA组、PLLA组和SBS组之间差异无统计学意义(P均>0.05)。各组间在反映内膜增生的指标(平均内膜厚度、新生内膜面积、面积狭窄百分比)上差异均无统计学意义(P均>0.05)。各组均无支架内狭窄(面积狭窄百分比≥50%)发生。结论:这4种采用不同涂层的SES支架均可以显著抑制健康小型猪冠状动脉支架置入术后4周时的内膜增生。采用可降解的PLGA和PLLA涂层的SES有良好的组织相容性,而非降解的EVAC涂层SES有较重的炎症反应。

OCT观察PCI术后可降解及永久性聚合物药物涂层支架内新生内膜增生的差异

目的:通过光学相干断层显像(optical coherence tomography,OCT)观察经皮冠状动脉介入治疗(percutaneous coronary intervention,PCI)术后1年,聚合物可降解药物涂层支架(Firehawk)与永久性聚合物药物涂层支架(Xience系列)内新生内膜增生的差异,旨在观察可降解聚合物及永久性聚合物对支架内新生内膜增生的影响。方法:本研究为单中心、回顾性设计,入选2014年1月—2019年6月在南京市第一医院心内科行PCI术且术后1年有冠脉造影+OCT检查资料的患者;依据术中植入的药物涂层支架的不同类型分为Firehawk组和Xience组;比较两组临床基线资料、PCI术中参数及术后复查OCT的相关指标。结果:本研究共入选106例患者,其中Firehawk组52例,Xience组54例。两组患者的临床基线资料(包括年龄、性别、高血压病史、糖尿病史、吸烟史、血脂指标以及药物如阿司匹林、氯吡格雷/替格瑞洛、他汀、β受体阻滞剂、ACEI/ARB服用史)在PCI术前及术后1年差异无统计学意义(P>0.05);两组患者PCI术中参数(包括靶血管分布、支架直径及长度、预扩及后扩比例、最大预扩/后扩球囊直径、最大预扩/后扩压力)差异无统计学意义(P>0.05);术后1年复查OCT提示,两组患者的支架内增生情况(包括最大新生内膜厚度、最大新生内膜面积、最小管腔面积、最小管腔直径、再狭窄率、同质性比例)差异无统计学意义(P>0.05)。结论:聚合物可降解与永久性聚合物药物涂层支架植入术后1年,支架内新生内膜增生的性质特点类似。

EXCEL可降解涂层雷帕霉素洗脱支架长期临床应用的安全性和有效性

目的:评估EXCEL可降解涂层雷帕霉素洗脱支架置入3年后的安全性和有效性。方法:连续入选我院100例冠心病住院患者,均单一置入EXCEL支架。术后接受双联抗血小板治疗(氯吡格雷和阿司匹林)6个月,随后单用阿司匹林。术后平均8个月实施造影随访及冠状动脉内超声检测。观察术后3年主要不良心脏事件(MACE)、全因死亡和血栓事件发生率。结果:100例患者均完成3年临床随访。1年时发生4例(4.0%)靶病变血运重建,无死亡和非致死性心肌梗死发生,1年MACE发生率为4.0%。3年随访时共6例(6.0%)MACE发生,包括靶病变血运重建4例(4.0%)和心性死亡2例(2.0%)。3年累计全因死亡率4%,包括心性死亡2例(2.0%),脑卒中和肺癌导致的非心性死亡各1例(2.0%),术后3年共发生支架内血栓事件2例(2.0%),其中很可能的支架内血栓事件仅1例(1.0%)。造影随访支架内再狭窄率3.6%(4/112),支架内晚期管腔丢失(0.12±0.34)mm。冠状动脉内超声检查共发现4处晚期支架贴壁不良(发生率6.3%,4/64),但随访期间无任何临床事件发生。结论:EXCEL支架置入术后患者的靶病变血运重建及MACE发生率一直处于较低水平,提示其早期临床获益可持续至术后3年。这一结论有待大规模、随机对照及随访期更长的临床研究证实。

一种新型可降解聚合物涂层-雷帕霉素洗脱支架对猪冠状动脉新生内膜增生的影响

目的:评价可降解高分子材料聚丙交酯-乙交酯(PLGA)作为支架药物载体的可行性及携带雷帕霉素的PLGA涂层支架的抗内膜增生作用。方法:在14头微型猪的3支冠状动脉分别植入钴铬合金裸支架(CoCr-BMS)、不载药的PLGA涂层支架(PCOS)和PLGA涂层雷帕霉素洗脱支架(PLGA-SES)。分别在支架植入后1个月和3个月时,复查冠状动脉造影,然后分离支架段血管行组织病理学分析。结果:共有12头动物存活,其余2头动物可能因麻醉剂相关的呼吸抑制而死亡。支架植入后1个月和3个月,不载药的PLGA涂层支架新生内膜面积和晚期管腔丢失与CoCr-BMS组相近,而PLGA-SES组则明显低于CoCr-BMS组。组织形态学示3组支架段血管损伤积分、炎症积分及再内皮化积分差异无统计学意义。结论:在猪冠状动脉支架模型中,PLGA涂层的支架设计具有良好的生物相容性和安全性;携带雷帕霉素的这种支架可抑制新生内膜形成,预防支架再狭窄的发生。

可降解镁合金表面载药涂层的制备和性能

在可降解AZ31B镁合金心血管支架表面成功制备了携带雷帕霉素的聚乳酸-聚三亚甲基碳酸酯(PLA-PTMC)共聚物涂层,评价了涂层的表面形貌、降解性能、血液相容性和药物释放性能。结果表明,PLA-PTMC共聚物作为载药涂层具有良好的柔韧性,表面均匀、光滑,降解周期超过1个月,血液相容性良好。涂层具有缓释雷帕霉素的功能,释药周期超过1个月,可在内膜增生期内有效抑制支架植入后再狭窄的发生,满足冠脉支架表面载药层的使用要求。

同期植入国产永久涂层支架和生物可吸收涂层支架后1年临床观察

目的比较国产永久涂层支架(Partner支架)和生物可吸收涂层支架(Excel支架)的疗效。方法冠心病患者同期接受Partner支架和Excel支架植入,记录术后心绞痛、心肌梗死和支架内血栓发生情况,1年后冠状动脉造影观察血管再狭窄和分支血管开口的变化情况。结果 107例患者共植入Partner支架128枚和Excel支架117枚,支架长度分别为26.4±12.4 mm和28.2±11.5 mm(P>0.05),支架直径分别为3.035±0.455 mm和3.076±0.432 mm(P>0.05)。经皮冠状动脉介入治疗(PCI)术后无支架内血栓和急性心肌梗死发生。两组1年的再狭窄率分别为8.4%和7.5%(P>0.05),边支血管开口直径变化无统计学意义(P>0.05)。结论国产永久涂层支架和生物可吸收涂层支架PCI术后1年冠状动脉造影随访结果相似。

药物洗脱性血管内支架药物涂层的研究进展

目前国内外支架开发过程中亟待解决的问题主要集中在三个方面:支架材料、支架表面涂层基质材科和药物的筛选、黏附和缓释。作者以血管内药物洗脱性支架的涂层基质制备的研究为重点,简要介绍目前涂层材料、特性及其制备方法的研究概况。

血管内超声虚拟组织学成像评价可降解涂层雷帕霉素洗脱支架对冠状动脉壁的影响

目的:应用血管内超声虚拟组织学成像(VH-IVUS)观察急性冠状动脉综合征患者置入生物降解涂层雷帕霉素洗脱支架(BSES)后对原位冠状动脉血管的长期影响。方法:对41例急性冠状动脉综合征患者在术后随访时(随访时间中位数=8个月)行VH-IVUS检查,通过BSES与不可降解涂层雷帕霉素洗脱支架(DSES)作对比,评价BSES置入后对急性冠状动脉综合征患者原位冠状动脉血管的影响以及邻近管腔坏死核心组织的出现率。根据既往置入支架的类型不同分为BSES组(21例)和DSES组(20例)。结果:两组间支架近端、远端节段和支架段晚期管腔丢失,差异均无统计学意义(P均>0.05)。两组间邻近管腔坏死核心组织出现率在支架段DSES组较BSES组明显升高(73%vs.36%,P<0.01),总出现率亦升高(63%vs.44%,P<0.05),差异有统计学意义;且多表现为多个邻近管腔坏死核心组织(74%vs.33%,P=0.06)。结论:随访时VH-IVUS检查提示,在急性冠状动脉综合征患者中BSES治疗处较DSES治疗处的病变形态更加稳定。