西罗莫司洗脱支架与紫杉醇洗脱支架抑制血管内膜增生的血管内超声比较

目的:利用血管内超声(IVUS)方法比较西罗莫司洗脱支架(CypherTM)与紫杉醇洗脱支架(TaxusTM)对冠心病患者新生内膜增生的抑制作用.方法:自2003-05至2007-04,167例冠心病患者(227处病变)行药物洗脱支架术,并在术后1年行冠状动脉造影和IVUS检查.其中107例患者(138处病变)置入CypherTM支架(Cypher组),60例患者(89处病变)置入TaxusTM支架(Taxus组).结果:两组患者基础临床情况及病变特征相似.造影结果分析显示,Cypher组支架内晚期管腔丢失、节段内晚期管腔丢失明显小于Taxos组[分别为(0.16±0.27)mm比(0.43±0.51)mm,P<0.01;和(0.20±0.32)mm比(0.38±0.33)mm,P=0.01],而两组近端和远端参考血管晚期管腔丢失差异无统计学意义[分别为(0.13±0.29)mm比(0.15±0.32)mm,P=0.689;和(0.08±0.12)mm比(0.09±0.16)mm,P=00500].IVUS分析显示,两组平均支架面积、平均管腔面积、最小支架面积、平均支架体积、平均管腔体积差异均无统计学意义,而Cypher组与Taxus组比平均内膜增生面积[(0.33±0.45)mm2比(1.29±1.26)mm2]、平均内膜增生面积百分数[(5.42±7.33)%比(17.38±13.75)%]、内膜增生最大面积百分数[(10.13±13.85)%比(31.56±20.99)%]、平均内膜增生容积[(2.23±6.50)mm3比(13.43±18.59)mm3]和平均内膜增生容积百分数[(1.59±4.10)%比(8.62±9.90)%],Cypher组均较Taxus组明显减小(P<0.0001),差异均有统计学意义.结论:CypherTM支架治疗冠心病一年再狭窄发生率较低,与TzxusTM支架相比,抑制内膜增生作用更显著.     

定量冠状动脉造影对糖尿病患者靶病变及参考血管的评价

目的 对比血管内超声(IVUS)与定量冠状动脉造影(QCA)对于冠心病合并糖尿病患者靶病变和参考血管定量测量结果,评价QCA的准确性,以指导临床的干预治疗.方法 2型糖尿病患者52例,男35例,女27例,年龄(62.3±7.1)岁.接受QCA和IVUS检查.以IVUS测量最小面积处斑块负荷结果作为因变量,以QCA定量测量的病变血管狭窄程度作为自变量,进行相关和回归分析,得到相关系数,建立回归方程.并对比近、远端参考血管直径两类方法测量值.结果 QCA冠状动脉狭窄程度测量结果同IVUS最小面积处斑块负荷结果的回归方程(斜率:0.8286,P=0.001)显示二种方法的测量结果有明确的同步变化趋势和相关性(r=0.691,P＜0.001).但QCA测量结果(57.9%±15.5%)较ivus(53.5%±12.9%)高估了病变的严重程度(差值为4.6%±1.2%).本组患者为血管负性重构,重构指数(RI)为0.87±0.23.相对于近、远端参考血管的管腔直径测量误差[(0.24±0.06)mm和(0.07±0.01)mm]而言,QCA对近、远端参考血管的血管直径的测量误差[(0.81±0.24)mm和(0.64±0.17)mm]更为明显.结论由于糖尿病患者广泛的血管重构(尤其是负性重构),使QCA易高估罪犯血管严重程度.同时,QCA因无法准确显示斑块负荷,而导致造影显示为"正常"血管段,从而低估近远端参考血管直径.     

辛伐他汀对支架置入后兔腹主动脉内膜增生的影响

目的 观察辛伐他汀对兔腹主动脉支架置入后内膜增殖的影响.方法 30只新西兰大白兔随机分为对照组和辛伐他汀治疗组.采用含1.5%胆固醇的高脂饮食加腹主动脉内皮剥脱术制作兔腹主动脉粥样硬化模型.内皮剥脱术后第12周实验组和对照组服用阿司匹林25 mg/d,氯吡格雷12.5 mg/d, 3 d后,分别行支架置入术.术后实验组继续服用辛伐他汀5 mg/d,服药至第30天处死动物,取腹主动脉含支架段血管,进行血管壁组织形态学变化观察和检测细胞周期抑制蛋白P27kip1、增殖细胞核抗原(PCNA)在各组的表达量的变化.结果 血管超声发现内皮剥脱术后第10周实验组和对照组腹主动脉均可见有不同程度的粥样硬化斑块和血管内狭窄.组织形态学观察发现服用辛伐他汀的实验组兔腹主动脉支架段内的血管内膜厚度(0.107±0.072 mm,与对照组0.133±0.047 mm比,P=0.006)、新生内膜面积(0.975±0.084 mm2,与对照组1.350±0.043 mm2比,P=0.001)均明显降低,且血管的狭窄程度较轻(20.460%±2.325%,与对照组31.020%±1.904%比,P=0.002).实验组兔腹主动脉支架段内的血管新生内膜中的血管平滑肌细胞(VSMC)的胞核P27kipl蛋白表达量明显升高(7.149±0.305,与对照组2.997±0.310比,t=9.551,P＜0.05),而血管新生内膜中VSMC的胞核PCNA表达量明显降低(着色强度IS为3.003±0.192, 与对照组着色强度IS 5.268±0.475比,t=4.423,P＜0.05).结论 辛伐他汀能明显抑制支架置入术后血管内膜增生.其机制可能为通过上调P27kip1蛋白表达量,使增殖标志物PCNA表达量降低,而对VSMC增殖周期起负调控作用,达到抑制VSMC增殖和新生内膜的增生.     

支架影像增强显影技术及其对球囊后扩张的指导作用

目的:探讨支架影像增强显影技术(StentBoost,SB)增强冠状动脉(冠脉)支架显影以及对球囊后扩张的指导作用。方法:收集2009-03至2010-07经皮冠脉介入治疗(PCI)术后在SB指导下给予球囊后扩张的184例患者资料,平均年龄(64.5±10.9)岁(42～83岁),对其后扩张前后SB测量数据进行比较。其中52例(28.26%)患者给予血管内超声(IVUS)检查,并分别对冠脉狭窄程度定量分析(QCA)、IVUS和SB检测数据进行相关性分析。结果:后扩张后较后扩张前支架内最小直径[(2.72±0.35)mm vs.(2.42±0.39)mm]、支架内最大直径[(3.26±0.37)mm vs.(3.09±0.38)mm]及支架内平均直径[(2.99±0.36)mm vs.(2.76±0.43)mm]均明显增大,支架偏心指数(0.17±0.04 vs.0.22±0.06)明显减小,差异均有统计学意义(P<0.001)。支架内最小直径IVUS与SB的相关性r=0.979,P<0.0001;冠脉狭窄程度定量分析与SB的相关性r=0.973,P<0.0001;QCA与IVUS的相关性r=0.964,P<0.0001。结论:SB与IVUS具有良好的相关性,且在评价支架置入效果以及指导高压球囊后扩张方面具有临床实用价值。     

雷帕霉素药物洗脱支架对糖尿病小型猪冠状动脉支架置入后内膜增生的影响

目的:评估雷帕霉素药物洗脱支架(SES)对糖尿病小型猪冠状动脉支架置入后内膜增生的作用.方法:建立链脲菌素诱导的糖尿病小型猪模型(糖尿病组,n=12),随机选取2支冠状动脉置入SES,共计置入24枚支架,术后饲养6个月,与非糖尿病置入SES支架的小型猪模型(对照组,n=12)比较冠状动脉造影、血管内超声及组织切片检查结果.结果:两组动物支架置入冠状动脉分布,术前参照血管直径[糖尿病组:(2.78±0.35)mm,对照组:(2.81±0.29)mm]及术后即刻最小管腔内径[糖尿病组:(2.90±0.42)mm,对照组:(2.89±0.33)mm]均相似(P均>0.05).术后6个月糖尿病组支架内狭窄程度[(35.6±9.2)%和(7.9±3.1)%,P<0.001]、支架内晚期管腔丢失[(0.32±0.09)mm和(0.09±0.04)mm,P<0.001]、新生内膜厚度[血管内超声:(0.35±0.12)mm和(0.11±0.08)mm,P<0.05]及新生内膜面积[血管内超声:(1.29±0.51)mm~2和(0.26±0.11)mm~2,P<0.001;组织切片:(1.24±0.76)mm~2和(0.19±0.08)mm~2,P<0.05]均显著高于对照组.结论:糖尿病小型猪冠状动脉置入SES后内膜增生程度显著高于无糖尿病模型.     

国产与进口西罗莫司洗脱支架置入后血管内超声随访的对比

目的 利用血管内超声对比观察国产与进口西罗莫司洗脱支架对冠心病患者支架术后新生内膜增生的抑制作用.方法 2003年5月至2007年3月,对215例冠心病患者(317处病变)置入西罗莫司洗脱支架,并在术后1年行冠状动脉造影和血管内超声(IVUS)检查.其中Firebird组108例患者(147处病变)置入国产西罗莫司洗脱支架(Firebird支架),Cypher组107例患者(138处病变)置入进121西罗莫司洗脱支架(Cypher支架).结果 两组患者一般临床情况差异无统计学意义.两组靶病变部位、病变长度、狭窄程度及病变类型差异均无统计学意义,但Firebird组术后最小管腔直径大于Cypher组[(2.88±0.43)mm比(2.78±0.33)mm,P＜0.05].随访定量冠状动脉造影分析显示,Firebird组与Cypher组支架内晚期管腔丢失[(0.17±0.29)mm比(0.16±0.27)mm,P＞0.05]和节段内晚期管腔丢失[(0.18±0.36)mm比(0.20±0.32)mm,P＞0.05]差异均无统计学意义.IVUS分析显示,与Cypher组比较,尽管Firebird组支架面积[(6.99±2.25)mm~2比(6.46±1.71)mm~2,P＜0.05]、管腔面积[(6.89±2.30)nm~2比(6.36±1.73)mm~2,P＜0.05]、支架体积[(162.5±68.9)mm~3比(140.8±57.9)mm~3,P＜0.01]、管腔体积[(160.4±69.5)mm~3比(138.6±57.6)mm~3,P＜0.01]及最小支架面积[(5.40±1.85)mm~2比(4.92±1.43)mm~2,P＜0.05]均较大,但两组的内膜增生容积[(2.09±5.46)mm~3比(2.23±6.50)mm~3,P＞0.05]和内膜增生容积百分数[(1.68±5.84)%比(1.59±4.10)%,P＞0.05]差异均无统计学意义.结论 Firebird支架置人后再狭窄的发生率较低,抑制内膜增生作用与Cypher支架相似.     

急性冠状动脉综合征患者雷帕霉素洗脱支架晚期贴壁不良及其对临床预后的影响

目的 观察急性冠状动脉综合征(ACS)患者雷帕霉素洗脱支架晚期贴壁不良发生率及其对临床预后的影响.方法 观察2005年2月至2007年3月因ACS(ACS组,54例)和稳定性心绞痛(对照组,83例)行雷帕霉素洗脱支架治疗并于1年后行血管内超声检查患者,检测支架晚期贴壁不良发生率,并观察血管内超声检查后1年内主要不良心血管事件及支架内血栓发生率.结果 所有137例患者219处病变中,16例患者25处病变检测到晚期支架贴壁不良.25处晚期支架贴壁不良中ACS组和对照组分别为20处(22.2%)和5处(3.9%)(P＜0.001).两组患者参照血管外弹力膜面积、参照血管和支架段血管管腔面积和新生内膜面积均相似,但ACS组患者支架段血管外弹力膜面积[(15.34±5.44)mm2比(13.83±4.51)mm2,P=0.026]、支架段血管外弹力膜面积与参照血管外弹力膜面积比值(1.13±0.22比1.02±0.18,P＜0.001)、斑块和中膜面积[(8.43±3.93)mm2比(7.01±2.93)mm2,P:0.002]较对照组明显增大.Logistic多元回归分析显示,ACS(OR=6.477,P＜0.001)和支架长度≥23 mm(OR=3.680,P=0.025)为晚期支架贴壁不良的独立危险因素.血管内超声检查后临床随访1年,两组主要不良心血管事件发生率差异无统计学意义.结论 雷帕霉素洗脱支架置入后,ACS患者较稳定性心绞痛患者更多发生晚期支架贴壁不良,然而随访1年的主要不良心血管事件发生率差异无统计学意义.     

新型生物全降解药物洗脱支架置入小型猪冠状动脉后冠状动脉造影及连续血管内超声评价

目的评价聚左旋乳酸/无定形磷酸钙（PLLA/ACP）新型生物全降解药物支架置入猪冠状动脉6个月内支架弹性回缩及有效性。方法将16枚新型生物支架随机置入小型猪冠状动脉内,行冠状动脉造影检查（术后即刻、随访终点）和血管内超声（IVUS）检查（术后即刻、1个月、6个月）,并且,在术后1个月和6个月分别处死12、4只动物,取支架置入部位血管固定行苏木素-伊红（HE）染色,观察内膜增生情况和支架贴壁情况。结果各小型猪随访终点造影复查可见支架置入段血管血流通畅,无狭窄及血栓形成等现象。IVUS检查提示,平均支架面积和平均支架直径在置入术后1个月和术后6个月时分别与术后即刻比较,差异均无统计学意义[平均支架面积：（6.08±1.30）mm2、（6.00±0.60）mm2比（5.97±0.53）mm2,P〉0.05;平均支架直径：（2.76±0.30）mm、（2.76±0.14）mm比（2.75±0.12）mm,P〉0.05],提示支架未发生显著弹性回缩;病理形态学分析提示,支架置入段血管轻度狭窄,未见支架贴壁不良。结论新型生物全降解支架置入小型猪冠状动脉6个月后,未发现显著支架弹性回缩,具有足够的支撑性能;内膜增生程度较轻,能够保证管腔通畅。     

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.     

远端血管弹性对冠状动脉慢性完全闭塞病变开通后无复流的影响

目的利用血管内超声(IVUS)评价冠状动脉远端血管弹性对慢性完全闭塞(CTO)病变开通后出现无复流或血流减慢的影响。方法回顾性分析2017年10月至2018年12月在首都医科大学附属北京安贞医院急诊中心行经皮冠状动脉介入治疗并成功置入支架完成IVUS检查的CTO病变患者34例。支架置入后远端血流正常组26例[心肌梗死溶栓治疗试验(TIMI)血流分级≥Ⅱ级],血流减慢组8例(TIMI血流分级0级或Ⅰ级)。分析可能导致无复流的病变形态学特点。结果两组患者血管钙化、中膜血肿、导丝行走于内膜下等比较,差异均无统计学意义(均P>0.05)。血流正常组的远端参考管腔面积[(4.09±1.71)mm2比(2.70±0.86)mm2,P=0.036]、远端血管收缩面积比[(15.96±3.95)%比(7.26±1.62)%,P=0.020]显著高于血流减慢组。logistic回归分析显示,远端血管弹性差(OR 13.75,95%CI 1.946~97.178,P=0.009)是支架置入后远端无复流及血流受限的独立预测因素。结论IVUS观察的CTO病变远端血管弹性是影响CTO病变开通后远端出现无复流的独立危险因素。     

可降解聚乳酸涂层西罗莫司洗脱支架在小型猪冠状动脉模型中的实验研究

目的评价新型L605钴铬合金平台可降解聚乳酸共聚物载体西罗莫司药物洗脱支架（bioabsorbable polymeric sirolimus-eluting stent,BPSES）在小型猪冠状动脉抑制新生内膜增殖的有效性和安全性。方法金属裸支架（bare mental stent,BMS）18枚、单纯可降解聚乳酸共聚物涂层支架（bioabsorbable polymer-only stent,BPOS）18枚以及BPSES 18枚被分别随机置入18头小型猪的前降支（18枚）、回旋支（18枚）以及右冠状动脉（18枚）。置入28天和90天,复查冠状动脉造影评价管腔丢失。置入7天、28天以及90天处死部分动物行塑料包埋硬组织切片染色组织形态学分析。结果置入28天及90天,BPSES与BMS相比,显著降低管腔丢失（28天0.54±0.45 mm比1.11±0.45mm,P=0.048;90天0.42±0.34 mm比0.96±0.41 mm,P=0.024）。在损伤积分相似的情况下,置入28天时BPSES较BMS新生内膜面积明显减少（0.90±0.40 mm2比1.88±0.71 mm2,P=0.015）,而在90天时亦叮见此趋势,7天、28天和90天BPSES和BPOS炎症反应及内皮化程度与BMS相似。结论BPSES在置入小型猪冠状动脉28天后,可以安全有效地抑制新生内膜增殖,90天时亦可见此趋势。     

无载体西罗莫司洗脱支架在小型猪冠状动脉模型中预防冠状动脉支架再狭窄的实验研究

目的评价新型无载体西罗莫司药物洗脱支架（polymer-free sirolimus-eluting stent,PFSES）在小型猪冠状动脉模型中抑制新生内膜增殖的有效性和安全性。方法金属裸支架（baremental stent,BMS,n=13）、无载体纳米微孔裸支架（polymer-free bare mental stent,PFBMS,n=13）、聚合物载体西罗莫司洗脱支架（polymeribased sirolimus-eluting stent,PSES,n=13）以及PFSES（n=13）被分别随机置入26头小型猪的前降支（n=26）和回旋支（n=26）。支架置入28天和90天后,复查冠状动脉造影评价管腔丢失。90天后处死部分动物（n=12）行塑料包埋硬组织切片染色组织形态学分析。结果置入28天（n=24）及90天（n=12）,PFSES与BMS相比,显著降低管腔丢失（0.69±0.49 mm比1.27±0.36 mm,P=0.041;0.77±0.44 mm比1.33±0.29 mm,P〈0.01）。在90天组织形态学分析中,损伤积分相似的情况下,PFSES较BMS明显减少新生内膜面积（2.412±1.149 mm2比4.475±1.345 mm2,P〈0.05）。PFSES炎症反应与BMS相似,且明显低于PSES。结论PFSES在置入小型猪冠状动脉28及90天后,可以安全有效地抑制内膜增殖和预防支架内再狭窄。     

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.     

Tacrolimus-eluting stent inhibits neointimal hyperplasia via calcineurin/NFAT signaling in porcine coronary artery model

AimsThe purpose is to elucidate the mechanism by which a newly developed tacrolimus-eluting stent (TES) prevents neointimal hyperplasia after stenting.Methods and resultsThe three major coronary arteries in juvenile swine were randomized to implantation of either a TES or bare metal stent (BMS). Twelve weeks after stenting, the TES showed 29% less neointimal area than the BMS. Immunohistochemical staining showed that the expression of calcineurin was up-regulated in the neointima and media after stenting, and the TES inhibited this up-regulation. Western blotting demonstrated that the expression of calcineurin, nuclear factor of activated T cell (NFAT), and interleukin-2 (IL-2) was lower with the TES than with the BMS. To confirm the effect of tacrolimus on vascular smooth muscle cells (VSMCs) and its mechanism, cultured rat VSMCs were incubated with 12.5 μM of tacrolimus (tacrolimus group) or without tacrolimus (control group). The cell number of the tacrolimus group was significantly lower than that of the control group at 48 h of incubation. Western blotting demonstrated that tacrolimus decreased the expression of calcineurin, NFATc4, and IL-2 of cultured VSMCs. We confirmed that calcineurin small-interfering RNA (siRNA) decreased cell proliferation and the expression of NFATc4 and IL-2 in cultured VSMCs compared with negative control-siRNA.ConclusionThe newly developed TES inhibited neointimal hyperplasia after stenting via the calcineurin/NFAT/IL-2 signaling pathway, which is one of several mechanisms through which TES inhibits restenosis. Calcineurin may be an important molecular target to prevent restenosis after stenting.     

Revisiting late loss and neointimal volumetric measurements in a drug-eluting stent trial: analysis from the SPIRIT FIRST trial.

This study was conducted to reevaluate the significance of angiographic late loss and to assess the agreement between new proposed neointimal volumetric measurements derived from quantitative coronary angiography (QCA) and standard intravascular ultrasound (IVUS)-based parameters. Neointimal volumetric measurements may better estimate the magnitude of neointimal growth after stenting than late loss. In 56 in-stent segments (27, everolimus; 29, bare metal) in the SPIRIT FIRST study, we compared QCA measures with the corresponding IVUS parameters. Two IVUS-late loss models were derived from minimal luminal diameter (MLD) using either a circular model or a so-called projected MLD. QCA-neointimal volume was calculated as follows: stent volume (mean area of the stented segment x stent length) at post procedure - lumen volume (mean area of the stented segment x stent length) at follow-up (the stent length either from nominal stent length or the length measured by QCA). Videodensitometric neointimal volume was also evaluated. Each of the three neointimal volume and percentage volume obstruction by QCA showed significant correlation with the corresponding IVUS parameters (r = 0.557-0.594, P < 0.0001), albeit with a broad range of limits of agreement. Late loss and volumetric measurements by QCA had a broader range of standard deviation than those by IVUS. QCA-volumetric measurements successfully confirmed the efficacy of everolimus-eluting stents over bare metal stents (P < 0.05). Our proposed QCA volumetric measurements may be a practical surrogate for IVUS measurements and a discriminant methodological approach for assessment of treatment effects of drug-eluting stents.     

Expansion of the Multilink-Tristar stent after direct implantation and predilatation: comparison of clinical,angiography and intravascular ultrasound parameters

Coronary stenting has become the primary therapeutic option for many coronary lesions. As opposed to conventional stenting the advantages of direct stenting are a reduction of procedural time, radiation exposure and costs. However, data about the incidence of in-stent restenosis are so far not available. It was the aim of this prospective study to compare the expansion of the Multilink stent after direct stenting and predilatation by quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS). Between January 2000 and June 2001, 82 patients were assigned to direct stenting (46 lesions) or predilatation (40 lesions) in lesions of coronary arteries > 3 mm. The procedural success rate was 92% in patients undergoing direct stenting. The baseline clinical characteristics were similar in both groups. The comparison of the angiographic data shows that direct stenting was performed in lesions with a lower degree of stenosis (71 +/- 12% vs 79 +/- 11%, p = 0.01) and that significantly shorter stents were used (14.4 +/- 3.0 vs 17.8 +/- 4.1 mm, p = 0.0007). The mean stenosis length was not significantly different in either group (10.5 +/- 3.4 vs 11.7 +/- 4.3 mm, n.s.). The QCA data after stent implantation show no differences of either implantation technique. Stent expansion was assessed by IVUS estimation of the proximal, distal and minimal in stent area. The minimal in-stent area (9.53 +/- 3.23, mm2 vs 8.65 +/- 1.96 mm2, n.s.) and the stent symmetry index (0.88 vs 0.88 n.s.) were not different in either patient group. These results indicate that in this subset of selected coronary lesions > 3 mm, elective stent implantation with and without predilatation effectively can achieve comparable stent expansion as assessed by QCA and IVUS. In comparison to conventional stent implantation stents, which were implanted without predilatation, were significantly shorter to cover the same lesion length.     

The genous™ endothelial progenitor cell capture stent accelerates stent re‐endothelialization but does not affect intimal hyperplasia in porcine coronary arteries

Objectives : To study the effect of endothelial progenitor cell (EPC) capture on the vascular response to coronary stenting. Background : The introduction of drug‐eluting stents has reduced the need for target lesion revascularization, but their effect on delayed healing, inflammation, and vascular dysfunction has emphasized the need to design strategies that improve current DES. One such strategy is to improve endothelialization by capturing CD34‐positive cells (EPC) by the stent surface. The first human clinical trial using coronary EPC capture stents showed stent safety but neointimal thickness (NIT) was not reduced compared to bare metal stents (BMS). To understand these responses we studied the coronary response to the EPC capture stent in swine. Methods and Results : The stent, coated with murine antihuman monoclonal CD34 antibodies, was assessed with QCA guided stent implantation in normal swine coronary arteries for early endothelialization at 2 and 5 days, and NIT at 28 and 90 days in comparison to control stents carrying a non‐specific murine antibody or to BMS. The main finding was that while the EPC capture stent significantly improved early endothelialization it did not reduce NIT at 28 and 90 days. Conclusions : The EPC capture stent improves early endothelialization in swine but this does not affect neointimal thickness as compared to control stents at 28 and 90 days. © 2011 Wiley Periodicals, Inc.     

Vascular response to sirolimus-eluting stents delivered with a nonaggressive implantation technique: comparison of intravascular ultrasound results from the multicenter, randomized E-SIRIUS, and SIRIUS trials.

BACKGROUND: The effectiveness of SES to reduce the risk of restenosis was initially demonstrated in short lesions using stent implantation with routine pre-dilatation and post-dilatation. This intravascular ultrasound (IVUS) substudy of the E-SIRIUS trial sought to evaluate local arterial responses to sirolimus-eluting stents (SES) delivered with a stent implantation technique allowing direct stenting and only selectively applying high-pressure post-dilatation. METHODS AND RESULTS: IVUS was performed immediately after intervention and at 8-month follow-up in 51 patients randomised to either bare-metal stents (BMS; Bx-Velocitytrade mark; N=20) or SES (Cyphertrade mark N=31). Direct stenting was allowed (24%) and post-dilation was performed only selectively (32%). Lumen dimensions, intimal hyperplasia and vessel remodeling were compared between SES and BMS. Subsequently, results of SES in the E-SIRIUS IVUS substudy (N=31) were compared to those of SES in the IVUS substudy of the SIRIUS trial (N=137). SES in SIRIUS IVUS substudy were delivered with 100% pre-dilatation and 77% post-dilatation. Baseline stent and reference segment measurements were similar between BMS and SES in E-SIRIUS IVUS patients. Using SES there was a 96% reduction in intimal hyperplasia volume within the stented segment (1.8+/-4.9 vs 50.6+/-39.7 mm3, P<0.001) and a significantly larger minimal lumen cross sectional area at 8-month follow-up (4.5+/-1.1 vs 2.3+/-0.9 mm2, P<0.001). No vessel remodeling was observed with the use of SES. The applied stent implantation technique resulted in a minimal stent/reference vessel area ratio of 0.75+/-0.17 in E-SIRIUS SES as compared to 0.84+/-0.23 in SIRIUS SES (P=0.046). Mean intimal hyperplasia cross-sectional area at follow-up was 0.1+/-0.2 mm2 in the SES group of E-SIRIUS and 0.5+/-0.8 mm2 in the SES group of SIRIUS (P=0.003). CONCLUSIONS: An implantation technique of SES which includes direct stenting and minimizes the use of high-pressure post-dilatation results in less optimal stent expansion. However, follow-up results compare very favourable to those of BMS and are characterised by even less intimal hyperplasia than after a more forceful implantation of SES.     

新型钴铬合金可降解涂层西罗莫司洗脱支架在猪冠状动脉过度扩张模型中对新生内膜的影响

目的：评价L-605钴铬合金支架平台、聚丙交酯-乙交酯（PLGA）共聚物载体西罗莫司药物洗脱支架在小型猪冠状动脉过度扩张模型中的安全性和有效性。方法裸金属支架（BMS,15枚）、已上市可降解涂层西罗莫司药物洗脱支架（EXCEL,21枚）和钴铬合金PLGA共聚物载体西罗莫司药物洗脱支架（Co-P-SES,21枚）分组随机置入30头小型猪的前降支（LAD）28枚,回旋支（LCX）13枚,右冠状动脉（RCA）16枚。术后28 d、91 d及182 d复查冠状动脉造影,评价管腔丢失（LL）等指标后处死动物,进行组织形态学及组织病理学分析。结果术后28 d及91 d,各实验组的管腔丢失、新生内膜面积、炎症积分及内皮化积分差异均无统计学意义,但术后28 d Co-P-SES组在扫描电镜下观察内皮化程度优于EXCEL组;术后182 d,Co-P-SES组与EXCEL组在管腔丢失、炎症积分及内皮化积分中差异均无统计学意义,但在内弹力板环绕面积相似的情况下, Co-P-SES组的管腔面积大于EXCEL组[（4.31±0.94）mm2比（2.62±1.17）mm2,P=0.020）],新生内膜面积小于EXCEL组[（1.87±0.53）mm2比（0.84±0.41）mm2,P=0.004）],差异均有统计学意义。结论在小型猪冠状动脉过度扩张模型中,Co-P-SES的安全性与EXCEL类似,在内皮化及减少新生内膜形成方面可能存在一定优势,有必要进一步临床研究以更好地评价其安全性及有效性。