双源CT评价冠状动脉支架内再狭窄的意义

目的:通过双源CT(DSCT)与选择性冠状动脉造影(CAG)对支架评估的对比分析,探讨DSCT对冠状动脉支架内再狭窄的诊断意义。方法:42例同期行双源CT冠状动脉血管成像及选择性CAG检查的患者,分析比较DSCT诊断支架内再狭窄的敏感性、特异性及准确性。结果:①DSCT按病例数诊断支架内再狭窄的敏感性86.7%、特异性96.2%、阳性预测值92.9%、阴性预测值92.6%、准确性92.7%。②DSCT按支架数诊断支架内再狭窄的敏感性76.5%、特异性95.1%、阳性预测值86.7%、阴性预测值90.7%、准确性89.7%。③DSCT与CAG比较,诊断支架内再狭窄的差异无统计学意义。④DSCT对直径≥3.0mm支架的再狭窄检出的阳性预测值、特异性、敏感性均优于直径3.0mm支架。结论:双源CT在诊断支架内再狭窄方面接近CAG,可作为支架内再狭窄的评估手段之一。     

双源CT与冠状动脉造影在冠心病患者冠状动脉支架内再狭窄评估中的价值

目的通过对比分析双源CT(DSCT)与冠状动脉造影(CAG)评估支架内再狭窄(ISR)的结果,探讨DSCT评估冠状动脉ISR的能力。方法 106例同期行DSCT冠状动脉血管成像及选择性CAG检查的患者,以CAG结果为标准,分析比较DSCT诊断ISR的敏感性、特异性及准确性。支架所在管腔狭窄大于50%被认为ISR。结果 173枚支架中,除17枚支架不能评价外,其余156枚支架DSCT全部显影良好。DSCT显示有ISR的支架33枚,CAG证实存在ISR的支架38枚,DSCT显示111枚支架内通畅,CAG证实支架内通畅118枚。DSCT诊断ISR的敏感度和特异度分别为86.8%和94.1%,阳性预测值82.5%,阴性预测值95.7%,一致率为92.3%。DSCT对直径≥3.0 mm支架的再狭窄检出的阳性预测值、特异性、敏感性优于直径<3.0 mm支架。结论 (1)DSCT可清晰显示冠状动脉支架的位置、支架腔内情况及支架远近端血管。(2)支架内径是影响支架腔内图像显示的重要原因。(3)DSCT在评估ISR方面,基本取代CAG作为大直径支架(支架直径>3 mm)通畅情况的评估方式,作为无创评估ISR的手段之一。     

冠状动脉双源CT与冠状动脉造影成像对急诊胸痛患者诊断冠心病的价值

目的:以常规冠状动脉造影(CAG)为"金标准",探讨急诊胸痛患者双源CT(DSCT)冠状动脉血管成像诊断冠心病的价值,分析DSCT诊断冠心病的准确度、灵敏度、特异度、阳性预测值和阴性预测值。方法:对115例以胸痛为主诉的急诊就诊、临床怀疑冠心病拟行CAG的患者[男60例,女55例,平均年龄(66.37±10.29)岁]进行DSCT冠状动脉成像,统计分析DSCT对诊断冠状动脉不同程度狭窄冠心病的准确度、灵敏度及特异度,并与CAG结果对比。结果:共获得92例有诊断价值的病例,DSCT诊断冠状动脉中重度狭窄的准确度为94.6%,灵敏度、特异度、阳性预测值和阴性预测值分别为96.7%、90.6%、95.1%和93.5%。对于诊断轻度狭窄冠心病的灵敏度为70.6%,特异度为63.9%,阳性预测值为34.3%,阴性预测值为91.2%。结论:DSCT冠状动脉成像可作为临床冠心病可疑患者CAG手术前的预筛手段,当患者的冠状动脉为中重度狭窄时,诊断的准确度、灵敏度、特异度较高,DSCT与CAG有很好的一致性,其对是否需进一步CAG检查有较大的指导意义。DSCT对于冠状动脉轻度狭窄患者的阴性预测值较高,提示如果DSCT判定患者无冠状动脉病变,基本上无进一步行CAG的必要。     

CCTA诊断冠状动脉支架内再狭窄的价值及再狭窄相关因素分析

目的评价冠状动脉CT血管造影(CCTA)在诊断冠状动脉支架植入术后支架内再狭窄的价值,并对再狭窄支架方面的相关因素进行分析。方法对106例冠状动脉支架植入术后患者,分别行CCTA及冠状动脉造影(CAG)检查,将CAG的诊断结果作为金标准,评估CCTA诊断支架内再狭窄的灵敏度、特异度,并分析支架内再狭窄是否与支架部位、直径、长度及类型有关。结果 (1) CCTA对106例患者的174枚支架内再狭窄的诊断特异度、灵敏度、阴性预测值、阳性预测值分别是97. 3%、91. 7%、98. 6%、84. 6%,与CAG的诊断一致性较高(Kappa=0. 860)。(2)支架内再狭窄与支架直径、狭窄性病变是否处于血管分叉处有关,与支架长度、支架所在冠脉节段、支架类型无关。结论 CCTA对冠状动脉支架内再狭窄的诊断结果与CAG的诊断结果存在较高的一致性。支架内再狭窄的形成与支架直径及狭窄性病变是否处于血管分叉处有关。     

冠心病PCI术后再狭窄的临床分析

目的：了解冠心病冠状动脉介入治疗（PCI）术后再狭窄的原因,为预防再狭窄发生提供根据。方法：回顾性分析我院冠脉支架置入300例中冠脉造影随访的74例的临床、血管造影及处理资料。并根据随访结果有、无再狭窄分为再狭窄组（42例）,无再狭窄组（32例）,分析病人年龄、性别、冠心病易患因素,靶病变形态学及术后最小管腔开放直径（MLD）等因素与再狭窄的关系。结果：与无再狭窄组比较,再狭窄组的男性（34.4%比76.2%）、吸烟（46.9%比71.4%）、PCI术后管腔直径〈3.5mm（40.0%比62.2%）显著增加。结论：男性、吸烟、支架直径〈3.5mm与PCI后冠状动脉再狭窄有关。     

104例冠状动脉血管内支架置入术后的血管造影随访研究

目的探讨影响冠状动脉内支架植入术后再狭窄的因素。方法对2001-2003年成功接受冠状动脉内支架植入术后患者进行定量冠状动脉造影,分析冠状动脉狭窄程度、病变长度及血管直径参数的影响。结果104例病人的138处病变植入152个支架,再狭窄率为35.5%。再狭窄组病变血管植入支架的长度(22±6)mm明显大于非再狭窄组(18±6)mm,(P<0.001)。短支架的再狭窄率显著小于长支架及植入多个支架者(P<0.01)。再狭窄组直径小于3.0mm中小血管的比例明显多于非再狭窄组。BX支架的再狭窄率最高,达46%,Supra-G的再狭窄率最低,为10.5%。结论冠状动脉内支架植入术后再狭窄与支架长度、构型等因素有关,小血管内植入支架仍须慎重。     

药物洗脱支架和金属裸支架治疗弥漫病变的比较研究

目的比较冠心病患者弥漫病变采用药物洗脱支架和金属裸支架治疗的近期和远期预后,分析影响这类病变介入治疗预后的危险因素。方法研究对象为我院2004年4月至2005年8月接受置入单个长度>25.0mm支架治疗并且进行冠状动脉造影随访的205例患者,排除支架置入失败及支架置入位置不理想者。分为置入药物洗脱支架(DES)组(n=128)和置入金属裸支架(BMS)组(n=77)。所有的患者术后均接受阿司匹林300mg、氯吡格雷75mg等规范药物治疗。手术成功判定标准为至少用相互垂直的两个投照体位行冠状动脉造影,肉眼判定残余狭窄<20%和前向血流TIMI3级。再狭窄判定标准以复查冠状动脉造影定量分析支架内或支架邻近血管管腔直径狭窄程度≥50%。患者在支架术后6个月左右接受冠状动脉造影随访。结果共205例患者(男性181例,女性24例)227个靶病变置入382枚支架完成造影随访。其中C型病变占总数的93.8%,B2型病变为6.2%。双支或双支以上血管病变的患者比例达到86.8%。平均术前参考血管直径(2.88±0.43)mm。平均每个病变支架长度(40.09±12.94)mm,54.2%的病变接受了重叠置入支架。比较置入DES组和置入BMS组,两组的患者基本条件差异无统计学意义,在病变基本条件方面,DES组术前参考血管直径明显小于BMS组[(2.80±0.37)mm比(3.10±0.48)mm,P=0.005]。6个月随访结果显示再狭窄率DES组(15.4%)小于BMS组(48.4%),P<0.001。晚期支架内腔径丢失BMS组明显大于DES组[(0.94±0.76)mm比(0.39±0.53)mm,P<0.001]。靶病变血管重建率DES要明显好于BMS(11.6%比38.5%,P<0.001)。支架内再狭窄在置入DES组的局限性再狭窄比例大于置入BMS组(33.3%比18.2%,P=0.029)。对影响复杂弥漫病变支架再狭窄因素的多元logistic回归分析发现,采用支架重叠置入(OR=2.82,P=0.017)和支架类型(OR=5.71,P<0.001)是对复杂弥漫病变支架内再狭窄影响最大的危险因素。结论我们的研究发现对于复杂弥漫病变的治疗,药物洗脱支架有着良好的治疗效果,较金属裸支架能明显减低再狭窄率。对于弥漫病变,我们应该使用长支架,尽可能减少支架重叠置入的数量。     

延迟支架置入术在高血栓负荷急性ST段抬高型心肌梗死患者急诊冠状动脉介入治疗中的应用

目的观察高血栓负荷急性ST段抬高型心肌梗死(STEMI)患者直接经皮冠状动脉介入治疗(PCI)后靶病变的变化及延迟支架置入情况。方法入选48例高血栓负荷STEMI患者,急诊予单纯球囊扩张和(或)冠状动脉血栓抽吸,梗死相关动脉前向血流心肌梗死溶栓试验(TIMI)血流分级3级,7 d后复查冠状动脉造影(CAG),根据靶病变血管狭窄情况必要时置入支架治疗。观察靶病变变化的相关数据,包括狭窄程度、长度、近端参考血管直径、远端参考血管直径,比较老年患者(≥60岁)和中青年患者(<60岁)支架置入比例。结果 7 d后复查CAG显示靶病变直径狭窄程度较直接PCI时减轻(35.5%±14.1%比48.8%±11.0%,P<0.01)、病变长度缩短[(15.69±5.36)mm比(18.94±5.37)mm,P<0.01],靶病变近端参考血管直径[(3.29±0.33)mm比(3.24±0.32)mm,P=0.02]和远端参考血管直径[(3.18±0.33)mm比(3.08±0.33)mm,P<0.01]增大;其中,39.6%(19/48)患者因靶病变狭窄>50%置入支架,老年患者和中青年患者置入支架比例分别是56%(9/16)、31%(10/32)(P=0.04)。结论对于中青年高血栓负荷不适宜直接支架置入术的STEMI患者急诊予单纯球囊扩张和(或)血栓抽吸即时开通梗死相关动脉,再延迟必要时支架置入治疗策略是安全、有效的。     

药物洗脱支架治疗后冠状动脉再狭窄相关因素的分析

目的探讨药物洗脱支架治疗后冠状动脉再狭窄与临床和造影的相关因素。方法入选416例冠状动脉造影(CAG)资料完整的冠心病患者,男性328例,女性88例,共置入支架470枚,按照CAG结果分为再狭窄组59例和无再狭窄组357例,平均造影随访时间(7．91±2．37)个月。结果再狭窄组CAG示61枚支架发生再狭窄(13．0％),女性、既往冠状动脉旁路移植术(CABG)病史、慢性闭塞(CTO)病变病史、最大球囊释放压力、置入支架长度与术后再狭窄相关(P<0．05);置入支架血管直径与再狭窄高度相关(OR=0．61,95％CI:0．43～0．82,P< 0．01)。结论女性、既往CABG病史、CTO病变、血管直径、置入支架长度是支架术后再狭窄的危险因素,而糖尿病史等与再狭窄无关。     

冠状动脉支架内再狭窄临床相关因素分析

目的　探讨冠状动脉支架内再狭窄与临床因素的关系。方法　前瞻性选择了冠心病易患因素、靶病变长度、支架术后管腔最小直径等 17项观察指标 ,对成功置入冠状动脉内支架 (coronarystent ,CS)并进行冠状动脉造影随访的 81例病人 (10 6条靶血管、12 2枚支架 )进行临床资料分析。单因素和多因素回归分析上述各种临床因素与再狭窄的关系。结果　 81例中有 2 7例病人的 33处原支架内发生再狭窄 ,靶病变再狭窄率为 2 7 0 %(33/ 12 2 )。单因素分析发现 :再狭窄组病人中空腹血清胰岛素 >15 μU·mL-1、血管病变长度≥ 15mm、支架术后管腔最小直径 <3 0mm者的比率明显高于无再狭窄组 (分别为 5 9 3%、33 3% ,P <0 0 5 ;6 3 6 %、38 2 % ,P <0 0 5 ;5 4 5 %、2 9 2 % ,P <0 0 1)。多元Logistic回归分析发现 :支架术后管腔最小直径 <3 0mm、靶病变长度≥15mm、空腹血清胰岛素 >15 μU·mL-1是CS术后再狭窄的独立危险因素。结论　较小的支架术后管腔最小直径、过长的靶病变、高胰岛素血症是CS术后再狭窄的最重要的独立危险因素。     

双源CT在冠状动脉支架内再狭窄诊断中的价值

目的 参照定量冠状动脉造影结果,评价双源CT在冠状动脉支架内再狭窄诊断中的价值.方法 对55例支架术后出现胸闷、胸痛的冠心病患者,在术后6～12个月行双源CT检查及定量冠状动脉造影.以定量冠状动脉造影结果为参照,评价双源CT诊断支架内再狭窄的真阳性、真阴性、假阳性、假阴性,并计算敏感性、特异性、阳性预测值、阴性预测值.分析心率、置人支架情况对双源CT诊断性能的影响.结果 55例患者共置入89枚支架,其中31.5%(28/89)的支架经冠状动脉造影证实发生支架内再狭窄.双源CT诊断支架内再狭窄的敏感性、特异性、阳性预测值、阴性预测值分别为89%、87%、76%和95%.双源CT诊断心率＜70次/min及≥70次/min患者支架内再狭窄的敏感性(94%比82%)、特异性(88%比90%)、阳性预测值(76%比75%)、阴性预测值(97%比93%)差异无统计学意义(P＞0.05).双源CT诊断重叠支架、分叉部位支架与单支架再狭窄的敏感性(84%比100%)、特异性(81%比96%)、阳性预测值(70%比90%)和阴性预测值(91%比100%)差异无统计学意义(P＞0.05).双源CT诊断直径≥3.50 mm支架、直径3.00 mm支架和直径≤2.75mm支架发生再狭窄的特异性(分别为100%、80%和66%,P＜0.05)和阳性预测值(分别为100%、95%和53%,P＜0.05)差异有统计学意义.结论 双源CT对大直径支架的再狭窄有较好的诊断性能,且不受心率和支架分布情况的影响.

Abstract：

Objective To evaluate the value of dual source computed tomography coronary angiography(DSCT-CA)on detecting in-stent restenosis(＞ 50% luminal narrowing)in symptomatic patients referred for quantitative coronary angiography(QAC). Methods Fifty five patients(43 males)with chest pain after coronary stent implantation within 6 - 12 months were evaluated by DSCT-CA and QAC. The sensitivity, specificity, positive predictive value(PPV)and negative predictive value(NPV)of DSCT-CA were calculated using coronary angiography as gold standard. Results Eighty nine stents were implanted.In-stent restenosis was evidenced in 28 stents(31.5%)by QAC. The sensitivity, specificity PPV and NPV of DSCT-CA for the diagnosis of in-stent restenosis was 89%, 87%, 76% and 95%, respectively.Diagnostic efficiency was not affected by heart rate and the sensitivity was 0. 94 vs. 0.82, the specificity 0. 88 vs. 0. 90, the PPV 0. 76 vs. 0.75 and the NPV 0. 97 vs. 0. 93(all P ＞ 0. 05)between patients with heart rate ＜70 beats/min and patients with heart rate≥70 beats/min. The sensitivity(84% vs. 100%),specificity(81% vs. 96%), PPV(70% vs. 90%)and NPV(91% vs. 100%)were similar between overlapping or bifurcations stents and single stents. The specificity(100% vs. 80% vs. 66%)and PPV (100% vs. 95% vs. 53%)were significantly higher in the groups with stents ≥3.50 mm, stents 3.00 mm than in stents ≤2. 75 mm(both P ＜ 0. 05). Conclusion Diagnostic efficiency of in-stent restenosis with DSCT-CA in the large diameter stent is better than in the small diameter stent and the diagnosis efficacy is not affected by heart rate and stent distribution.     

双源CT对冠状动脉支架内再狭窄诊断价值的Meta分析

目的评价双源CT在经皮冠状动脉支架置入术后支架内再狭窄的诊断价值。方法计算机检索2005年12月1日～2011年12月30日Pubmed,Embase,Cochrane library,CNKI,CBMdisc数据库,查询双源CT在诊断冠状动脉支架内再狭窄研究的中、英文文献。对纳入文献进行质量评估,计算双源CT诊断冠状动脉支架内再狭窄灵敏度（SE）、特异度（SP）及其95%可信区间（CI）,绘制及计算受试者工作特征曲线（SROC）和曲线下面积（AUC）。结果共纳入9篇文献。基于支架分析,双源CT诊断冠状动脉支架内再狭窄的合并灵敏度为0.91（95%CI：0.86～0.95）,特异度为0.92（95%CI：0.90～0.94）,AUC为0.97。双源CT对诊断冠状动脉内大支架（直径≥3mm）再狭窄的准确度高于小支架（直径〈3mm）,差异有统计学意义（P〈0.05）。不可评价支架的合并构成比为0.066（95%CI：0.05～0.09）。结论双源CT诊断冠状动脉支架内再狭窄的准确度高,适用于直径≥3mm的支架,是冠状动脉支架随访和评价的一种有效且无创的检测方法。     

320排CT冠状动脉血管成像与冠状动脉造影评估冠状动脉支架内再狭窄程度的对比分析

目的评价320排CT冠状动脉血管成像(CCTA)在冠状动脉支架内再狭窄评估中的临床应用价值。方法以选择性冠状动脉造影(CAG)为金标准,应用320排CCTA评价100例患者冠状动脉支架内再狭窄的程度。将冠状动脉支架内管径分为无狭窄、轻度狭窄(≤50%)、中度狭窄(51%～75%)和重度狭窄或闭塞(76%～100%)4个等级,分析320排CCTA与CAG评估狭窄程度的一致性。其中再狭窄≥50%为阳性,包括支架内及支架两端5mm范围内的血管段。统计学方法采用Kappa评价方法。结果 100例患者中共评价分析175枚支架,CAG示冠状动脉支架内再狭窄44枚,320排CCTA正确诊断42枚,漏诊2枚,误诊10枚,敏感度为95.45%、特异度为92.37%、准确度为70.29%、阳性预测值为80.77%、阴性预测值为98.37%。在P<0.05的检验标准上,Kappa值为0.5688,320排CCTA和CAG对支架内狭窄程度评估一致性好。结论 320排CCTA能够准确显示支架内再狭窄的部位及程度,而且无创、重复性好,图像直观可信,具有很高的临床应用价值。     

New diagnostic technique in multi-slice computed tomography for in-stent restenosis: pixel count method

OBJECTIVES: A diagnostic technique to objectively determine coronary in-stent stenosis was developed with multi(16)-slice computed tomography (MSCT), and it was compared with coronary angiography (CAG) in clinical cases. BACKGROUND: MSCT is expected to replace coronary angiography as a new non-invasive examination. Evaluation of highly calcified or in-stent lesions with CT is generally thought to be difficult. METHODS: Twenty lesions among 16 consecutive patients that were implanted with coronary stents were examined with both MSCT and CAG at follow-up. The minor axis cross sections of the stents were reconstructed at intervals of 1.5 mm with multiplanar reformation (MPR). The pixel with a higher CT value than the lowest CT value in the standard cross section at the proximal site out of stent was counted to determine the presence/absence of a stenotic lesion. RESULTS: Among 20 lesions, one case was not able to be evaluated with MSCT. MSCT correctly detected 3 of 4 cases with in-stent stenosis (sensitivity 75%), and 14 of 16 cases with no in-stent stenosis (specificity 88%, negative predictive value 93%, positive predictive value 75%). If analysis was made per-artery, sensitivity and specificity were 100% (3 of 3) and 87% (13 of 15), respectively, for detection of in-stent stenosis. CONCLUSIONS: This study was performed to examine a unique diagnostic technique: pixel count method, for coronary in-stent stenosis with MSCT. It showed that the coronary in-stent stenosis could be determined when stent struts were clearly imaged. Further examination is required with various stents, especially those with a diameter of 3.0 mm or smaller.     

64层螺旋CT冠状动脉支架成像效果的影响因素

目的 探讨64层螺旋CT冠状动脉支架成像效果的影响因素.方法选取冠状动脉药物涂层金属支架植入术后行64层螺旋CT检查的病例116例,对支架部位图像质量采取半定量评价,分析支架直径、支架长度、支架材质、支架个数和钙化情况对支架部位CT图像质量的影响.结果 64层螺旋CT检出有意义支架内再狭窄的敏感度、特异度、阳性预测值、阴性预测值分别为85.7%、90.2%、60.0%、97.4%.直径2.75 mm以上支架的CT图像质量优于直径2.75 mm及以下的支架(P<0.001),非钙化病变的支架术后CT图像质量优于钙化病变(P<0.05).支架长度、支架材质和是否多支架对支架部位CT图像质量无影响.结论 64层螺旋CT能胜任冠状动脉支架术后复查.直径2.75 mm以上支架和非钙化病变的支架病例更适合用64层螺旋CT进行复查.     

Usefulness of 64-slice multislice computed tomography coronary angiography to assess in-stent restenosis.

OBJECTIVES: This study sought to evaluate the diagnostic accuracy of 64-slice multislice computed tomography (MSCT) coronary angiography in the follow-up of patients with previous coronary stent implantation. BACKGROUND: Recent investigations have shown increased image quality and diagnostic accuracy for noninvasive coronary angiography with 64-slice MSCT as compared with previous-generation MSCT scanners, but data on the evaluation of coronary stents are scarce. METHODS: In 182 patients (152 [84%] male, ages 58 +/- 11 years) with previous stent (> or =2.5 mm diameter) implantation (n = 192), 64-slice MSCT angiography using either a Sensation 64 (Siemens, Forchheim, Germany) or Aquilion 64 (Toshiba, Otawara, Japan) was performed. At each center, coronary stents were evaluated by 2 experienced observers and evaluated for the presence of significant (> or =50%) in-stent restenosis. Quantitative coronary angiography served as the standard of reference. RESULTS: A total of 14 (7.3%) stented segments were excluded because of poor image quality. In the interpretable stents, 20 of the 178 (11.2%) evaluated stents were significantly diseased, of which 19 were correctly detected by 64-slice MSCT. Accordingly, sensitivity, specificity, and positive and negative predictive value to identify in-stent restenosis in interpretable stents were 95.0% (95% confidence interval [CI] 85% to 100%), 93.0% (95% CI 90% to 97%), 63.3% (95% CI 46% to 81%), and 99.3% (95% CI 98% to 100%), respectively. CONCLUSIONS: In-stent restenosis can be evaluated with 64-slice MSCT with good diagnostic accuracy. In particular, a high negative predictive value of 99% was observed, indicating that 64-slice MSCT may be most valuable as a noninvasive method of excluding in-stent restenosis.     

Role of vessel size as a predictor for the occurrence of in-stent restenosis in patients with diabetes mellitus

Intracoronary stents have been shown to reduce the rate of restenosis when compared with balloon angioplasty, but in-stent restenosis continues to be an important clinical problem. It was therefore the aim of this registry to identify procedural and angiographic predictors for the occurrence of in-stent restenosis. We analyzed 368 patients with 421 lesions who underwent coronary stent implantation between January 1998 and February 2000. Indications for the placement of a coronary stent were severe dissections (37%), suboptimal angiographic results (38%), restenotic lesions (20%), and graft lesions (4%). Angiographic follow-up was obtained in 270 patients (73%) with 293 lesions after 6 months. Clinical and angiographic variables were analyzed by univariate and multivariate models for the ability to predict the occurrence of in-stent restenosis, defined as a diameter stenosis >50%. In-stent restenosis was angiographically documented in 67 patients and 68 lesions (23%). Under all tested variables the reference luminal diameter before stent implantation (p = 0.006) and diabetes mellitus (p = 0.023) were identified as independent predictors for the occurrence of in-stent restenosis. The comparison of diabetic and nondiabetic patients according to vessel size revealed a 2 times higher rate of in-stent restenosis in small vessels (44% vs 23%, p = 0.002), whereas in vessels >3.0 mm the rate of in-stent restenosis was not significantly different between the 2 groups. In this registry, the clinical variable diabetes and the procedural variable reference vessel size were independent predictors for the occurrence of in-stent restenosis. In these patients, the rate of in-stent restenosis was as high as 45%.     

Assessment of coronary artery stent restenosis by 64-slice multi-detector computed tomography.

AIMS: We investigated the feasibility of assessing coronary artery stent restenosis using a new generation 64-slice multi-detector computed tomography-scanner (MDCT) in comparison to conventional quantitative angiography. METHODS AND RESULTS: MDCT was performed in 64 consecutive patients (mean age 58+/-10 years) with previously implanted coronary artery stents (102 stented lesions: mean stent diameter 3.17+/-0.38 mm). Each stent was classified as 'evaluable' or 'unevaluable', and in evaluable stents, the presence of in-stent restenosis (diameter reduction >50%) was determined visually. Results were verified against invasive, quantitative coronary angiography. Fifty-nine stented lesions (58%) were classified as evaluable in MDCT. The mean diameter of evaluable stents was 3.28+/-0.40 mm, whereas the mean diameter of non-evaluable stents was 3.03+/-0.31 mm (P=0.0002). Overall, six of 12 in-stent restenoses were correctly detected by MDCT [50% sensitivity (confidence interval 22-77%)] and in 51 of 90 lesions, in-stent restenosis was correctly ruled out [57% specificity (46-67%)]. In evaluable stents, six of seven in-stent restenoses were correctly detected, and the absence of in-stent stenosis was correctly identified in 51 of 52 cases [sensitivity 86% (42-99%) and specificity 98% (88-100%)]. CONCLUSION: Stent type and diameter influence evaluability concerning in-stent restenosis by MDCT. The rate of assessable stents is low, but in evaluable stents, accuracy for detection of in-stent restenosis can be high.     

Balloon angioplasty for the treatment of coronary in-stent restenosis: immediate results and 6-month angiographic recurrent restenosis rate

Objectives. The purpose of this prospective study was to evaluate the immediate results and the 6-month angiographic recurrent restenosis rate after balloon angioplasty for in-stent restenosis.Background. Despite excellent immediate and mid-term results, 20% to 30% of patients with coronary stent implantation will present an angiographic restenosis and may require additional treatment. The optimal treatment for in-stent restenosis is still unclear.Methods. Quantitative coronary angiography (QCA) analyses were performed before and after stent implantation, before and after balloon angioplasty for in-stent restenosis and on a 6-month systematic coronary angiogram to assess the recurrent angiographic restenosis rate.Results. Balloon angioplasty was performed in 52 patients presenting in-stent restenosis. In-stent restenosis was either diffuse (≥ 10 mm) inside the stent (71%) or focal (29%). Mean stent length was 16 ± 7 mm. Balloon diameter of 2.98 ± 0.37 mm and maximal inflation pressure of 10 ± 3 atm were used for balloon angioplasty. Angiographic success rate was 100% without any complication. Acute gain was lower after balloon angioplasty for in-stent restenosis than after stent implantation: 1.19 ± 0.60 mm vs. 1.75 ± 0.68 mm (p = 0.0002). At 6-month follow-up, 60% of patients were asymptomatic and no patient died. Eighteen patients (35%) had repeat target vessel revascularization. Angiographic restenosis rate was 54%. Recurrent restenosis rate was higher when in-stent restenosis was diffuse: 63% vs. 31% when focal, p = 0.046.Conclusions. Although balloon angioplasty for in-stent restenosis can be safely and successfully performed, it leads to less immediate stenosis improvement than at time of stent implantation and carries a high recurrent angiographic restenosis rate at 6 months, in particular in diffuse in-stent restenosis lesions.