冠状动脉慢性完全闭塞病变计算机断层扫描血管成像的形态学特征

目的分析冠状动脉慢性完全闭塞病变(chronic total occlusion,CTO)在双源计算机断层扫描(computed tomography,CT)血管成像上的形态学特点,并评估具有指导经皮冠状动脉介入(percutaneous coronary intervention,PCI)治疗价值的形态学特征。方法回顾性分析经冠状动脉造影(coronary angiography,CAG)证实为CTO病变患者的术前冠状动脉CT血管成像(coronary computed tomography angiography,CCTA)影像资料。评估并记录CCTA上所显示的各形态学指标,包括病变位置、闭塞血管长度、闭塞段血管近端呈钝形、闭塞段血管出现钙化;与CAG结果相比较,分析两者间显示的差异。结果 80例患者(82个CTO病变)CCTA结果显示82支血管闭塞,CCTA诊断CTO病变的敏感度为95.12%,特异度为97.14%;冠状动脉CTO病变45例(54.88%)位于右冠状动脉,CCTA测量闭塞段长度显著小于CAG测量所得,差异具有统计学意义[(28.29±14.15)mm vs.(38.90±23.48)mm,P0.001]。CCTA显示闭塞段血管近端呈钝形19例(23.17%),与CAG对照一致。CCTA显示58个(70.73%)CTO病变闭塞段血管内可见点状、结节状、条片状钙化灶,而CAG显示闭塞段血管存在钙化55个(67.07%),两者间比较差异无统计学意义(P0.05)。结论双源CT诊断冠状动脉CTO病变有较高敏感度及特异度,且可以显示闭塞段长度,近端形态及闭塞段钙化等有利于指导PCI治疗的形态学特征。     

术前CT血管成像对慢性完全闭塞病变介入治疗结果预测价值的研究

目的分析影响慢性完全闭塞病变(CTO)经皮冠状动脉介入治疗(PCI)结果的影像特征,评估术前CT血管造影成像(CCTA)对CTO介入治疗结果预测价值,以及对比J-CTO评分和CT-RECTOR评分系统对CTO介入结果的预测效能。方法回顾性分析113例患者,共114处病变血管,根据PCI结果分为成功组(84例)与失败组(30例)。分析CCTA影像特征,包括闭塞长度、血管弯曲角度、重构类型等,多因素logistic回归分析导致PCI失败的因素。ROC曲线下面积对比评估J-CTO评分和CT-RECTOR评分的预测效能。结果 PCI失败组的血管弯曲角度大于45°(30.0%比4.8%,P=0.001)、钝形闭塞(60.0%比14.2%,P<0.001)、钙化程度大于50%(36.7%比8.3%,P=0.004)、负性重构(66.7%比31.0%,P=0.001)、闭塞段长度[(22.06±16.09)mm比(16.15±10.67)mm,P=0.026]均大于PCI成功组。多因素logistic分析显示负性重构、血管弯曲大于45°、钝形闭塞的病变行PCI失败率高(均为P<0.05)。CT-RECTOR评分预测介入治疗成功率高于J-CTO评分(85.4%比76.8%,P<0.05),差异有统计学意义。结论负性重构、血管弯曲大于45°、钝形闭塞是影响CTO患者手术失败的主要因素;CT-RECTOR评分更有助于预测CTO行PCI手术结果,术前CCTA检查有助于预测PCI手术结果。     

586例冠状动脉慢性完全闭塞患者经皮冠状动脉介入治疗疗效及相关因素分析

目的:评估经皮冠状动脉介入治疗(PCI)对冠状动脉慢性完全闭塞(CTO)患者的治疗效果,并探讨影响介入治疗效果的相关因素。方法:回顾性分析586例经PCI治疗的CTO患者的临床资料,分析CTO患者行PCI治疗的疗效及相关影响因素。结果:CTO患者PCI的成功率为80%。术中并发症7.7%,分别是冠状动脉穿孔8例,心包压塞5例,支架血栓形成4例,严重心律失常(房扑、房颤、室性心动过速及室颤)22例,手术相关心绞痛6例。影响PCI治疗成功的患者自身因素有年龄(P=0.034)、高血压史(P=0.041)、糖尿病史(P=0.032)、发病至治疗的时间(P=0.008);病变相关因素有冠脉闭塞部位(P0.05)、冠脉分支迂曲程度(P=0.015)、闭塞血管远端缺如(P=0.044)及合并钙化(P=0.007)。结论:CTO患者进行PCI治疗的效果良好。患者的个人病史、病变特点及治疗是否及时是决定介入治疗成功的关键因素。     

慢性闭塞病变患者介入治疗后心肌血流和心电图及心功能变化

目的探讨慢性冠状动脉闭塞(CTO)病变患者PCI后梗死相关动脉(IRA)闭塞血管TIMI血流和心肌灌注(TMP)血流的变化;了解CTO病变PCI后心电图、心功能的变化。方法选择心绞痛或心电图异常的住院患者42例行冠状动脉造影检查,确诊为CTO病变,进行PCI支架置入术。分析术前、术后IRA的TIMI血流、TMP血流、心电图和心功能的变化。结果 CTO病变PCI后IRA的TIMI血流、TMP血流3级者分别为36例(85.7%)和25例(59.5%);PCI前、后心绞痛、心功能比较差异有统计学意义(P<0.05,P<0.01)。心电图Q波、ST段、T波异常与相关CTO均<30%,PCI前、后心电图显示Q波、ST段、T波异常共40次,前、后对比共17次(42.5%),无异常者23次(57.5%)。结论 CTO病变行PCI后,对冠状动脉再通、改善心肌血流灌注、改善心功能、缓解心绞痛症状以及对心电图异常的改变均有意义。     

冠状动脉CT血管造影对慢性完全闭塞病变患者介入治疗的预测价值

目的运用CT血管造影(CT angiography,CTA)分析影响慢性完全闭塞病变(chronic total occlusion lesions,CTO)介入治疗的病变特征及对介入治疗结果的预测价值。方法入选113例患者,分为介入治疗成功组(64例)与介入治疗失败组(52例)。收集患者资料,运用CTA分析两组患者CTO特征,并采用多因素logistic回归分析判断影响CTO介入治疗成功的因素,利用ROC曲线判断并评价CT-CTO评分和日本CTO评分(J-CTO评分)的诊断效能。结果介入治疗失败组患者闭塞段近端分叉(75.0%比54.7%,P=0.042)、闭塞段远端纤维帽形态不清晰(17.3%比4.6%,P=0.023)、闭塞段内是否存在钙化病变(73.1%比53.1%,P=0.033)、闭塞段长度[(26.0±16.6)mm比(16.8±11.3)mm,P=0.003]、闭塞段长度≥20 mm(46.2%比25.0%,P=0.007)均高于介入治疗成功组,差异均有统计学意义。多因素logistic回归分析显示,闭塞段远端纤维帽形态不清晰、闭塞段近端分叉、闭塞长度≥20 mm是影响CTO介入治疗成功的主要因素。ROC曲线下的面积CT-CTO评分预测介入治疗成功率(87.8%比73.9%,P0.05)高于J-CTO评分。结论闭塞段远端纤维帽形态不清晰、闭塞段近端分叉、闭塞段长度≥20 mm是影响CTO介入治疗成功的独立危险因素,CTA能够预测CTO介入治疗的成功率,与J-CTO评分相比,CT-CTO评分对介入治疗成功率具有更高的预测价值。     

冠状动脉慢性完全闭塞患者经PCI治疗后的临床效果及成功的影响因素

目的：评估介入治疗(PCI)对冠状动脉慢性完全闭塞(CTO)患者的治疗效果,并探讨影响介入治疗效果的相关因素。方法：回顾性分析我院心内科近期收治的586例经PCI治疗的CTO患者的临床资料。比较CTO患者在院内的介入治疗效果及相关影响因素。结果：PCI的成功率为80%。术中并发症较少(7.7%),其中术中冠状动脉穿孔8例,心包穿孔及心包压塞5例,支架血栓形成4例,严重心律失常(房扑、房颤、室性心动过速及室颤)22例,手术相关心绞痛6例。影响介入治疗成功的患者自身因素有年龄(P=0.034),高血压史(P=0.041),糖尿病史(P=0.032),发病至治疗的时间(P=0.008)；病变相关因素有冠脉闭塞部位(P<0.05)、冠脉分支迂曲程度(P=0.015)、闭塞血管远端缺如(P=0.044)及合并钙化(P=0.007)。结论：CTO患者进行PCI治疗的效果良好。患者的个人病史、病变特点、及治疗实施是否及时是决定介入治疗是否成功的关键因素。     

非梗死相关血管慢性完全闭塞对行急诊介入治疗的ST段抬高型心肌梗死患者预后的影响

目的:分析非梗死相关血管慢性完全闭塞(CTO)对接受直接经皮冠状动脉介入治疗(PCI)的急性ST段抬高型心肌梗死(STEMI)患者预后的影响。方法:选择2010-01至2011-06连续在我院确诊急性STEMI并行早期直接PCI治疗的185例患者,分为非梗死相关血管无CTO组(无CTO组)和非梗死相关血管合并CTO组(CTO组),共150例患者完成了1年随访,主要终点为1年时因心绞痛、再次心肌梗死(MI)、心力衰竭而住院或再次血运重建以及心血管死亡。结果:(1)无CTO组160例(86.5%),CTO组25例(13.5%),CTO组患者糖尿病及冠状动脉三支血管病变的比例均显著高于无CTO组(40.0%vs 20.0%,P=0.049;68.0%vs 36.3%,P=0.003);CTO组左心室射血分数显著低于无CTO组[(40.0±20.1)%vs(51.3±15.3)%,P0.05],差异均有统计学意义。(2)CTO组患者6个月、1年的心血管死亡以及1年时的主要终点发生率均显著高于无CTO组(26.3%vs 6.1%,P=0.013;31.6%vs 8.4%,P=0.010;52.6%vs 16.8%,P=0.001),差异均有统计学意义。(3)多因素分析显示,非梗死相关血管合并CTO[风险比(HR)=3.889,95%可信区间:1.239~4.206,P=0.020]、心原性休克(HR=3.229,95%可信区间:2.760~3.725,P=0.012)及冠状动脉三支血管病变(HR=2.008,95%可信区间:1.549~3.372,P=0.040)是行直接PCI的急性STEMI患者1年心血管死亡的独立预测因素。结论:非梗死相关血管存在CTO并接受直接PCI的急性STEMI患者多预后不良,非梗死相关血管合并CTO、心原性休克、冠状动脉三支血管病变是这类患者1年心血管死亡的独立预测因素。     

冠状动脉旁路移植术患者原位冠状动脉通畅率及行经皮冠状动脉介入治疗的研究

目的本研究旨在评估原位冠状动脉在冠状动脉旁路移植术(CABG)后的通畅率以及分析其进展为慢性完全闭塞(CTO)病变的危险因素。方法回顾性分析南京医科大学第一附属医院CABG术后因再发心绞痛复查冠状动脉造影患者44例,对其原位冠状动脉通畅率、病变进展程度以及其影响因素进行分析,并评估针对原位冠状动脉行经皮冠状动脉介入治疗(PCI)的效果。结果 44例患者CABG术前冠状动脉造影有21例(47.7%)至少存在1支原位冠状动脉CTO病变,CTO病变血管总数为26支(59.1%);CABG术后复查造影,10例(22.7%)原位冠状动脉进展为CTO病变;CABG术前狭窄90%的原位冠状动脉进展为CTO的概率是狭窄90%血管的3.9倍(70.0%比17.9%,P=0.005)。logistic多因素回归分析,术前左前降支(LAD)狭窄90%是原位冠状动脉LAD新发CTO的独立危险因素(OR 27.217,95%CI 1.801～411.268,P=0.017)。44例患者中有22例患者共30处原位冠状动脉病变具有PCI适应证,除1处因血管迂曲钙化,导丝不能通过而失败外,余29处(96.7%)均成功置入了药物洗脱支架(共63枚)。结论 CABG术后原位冠状动脉进展为CTO病变并不少见。CABG术前原位冠状动脉狭窄 90%可能是其重要的预测因素之一。针对CABG术后的原位冠状动脉行PCI是可行的。     

斑块钙化对双源CT冠状动脉造影诊断准确性的影响

目的定性、定量分析斑块钙化对双源CT冠状动脉造影诊断准确性的影响。方法回顾性分析双源CT冠状动脉造影诊断为冠心病,后行选择性冠状动脉造影的患者224例,共375处明显狭窄病变,其中234处为钙化病变。比较斑块不同钙化程度、钙化斑块血管直径、钙化斑块长度和钙化斑块血管分布对双源CT冠状动脉造影诊断冠状动脉狭窄准确性的影响。结果对轻中度钙化斑块和重度钙化斑块,双源CT分别高估管腔狭窄6.8%(P=0.0028)和18.8%(P0.0001),且高估狭窄在重度钙化斑块中更明显(P=0.002)。对血管直径较小和血管直径较大的钙化斑块,双源CT分别高估管腔狭窄7.2%(P=0.0026)和17.1%(P0.0001),且高估狭窄在血管直径较大时更明显(P=0.001)。对不同长度的钙化斑块,双源CT的诊断准确性未见差异(P=0.792)。结论斑块钙化使双源CT高估冠状动脉管腔狭窄,且钙化程度重和血管直径较大时更易出现。     

慢性完全闭塞病变行经皮冠状动脉介入治疗对供血动脉定量血流分数的影响

目的探讨冠状动脉慢性完全闭塞(CTO)病变成功行经皮冠状动脉介入治疗(PCI)对其供血动脉定量血流分数(QFR)的影响。方法入选上海交通大学医学院附属瑞金医院2017年7月至2021年1月成功行PCI的单支CTO病变且供血血管符合QFR计算标准的患者30例。分别于CTO病变血管开通前后应用不同的血流模型,即固定血流模型和对比剂血流模型,对供血血管进行QFR评估,观察CTO-PCI前后QFR值的变化,并收集患者的临床基线资料,分析其影响QFR值变化的因素。结果CTO-PCI术后供血血管对比剂血流QFR值显著高于术前[(0.74±0.17)比(0.69±0.19),P<0.001],且冠状动脉侧支循环Rentrop分级是预测QFR变化值的独立预测因素(β=0.36,P=0.043)。结论CTO-PCI术后供血血管QFR值是显著升高的,且与Rentrop侧支循环分级相关。     

Impact of 16-slice computed tomography in percutaneous coronary intervention of chronic total occlusions.

The main reason for failure of percutaneous coronary intervention (PCI) of chronic total occlusion (CTO) is because the calcified plaque prevents the guide wire crossing the occlusion. We aimed to identify the route, and characterize plaque components within CTO, using 16-slice computed tomography (MSCT). Twenty three angiographic CTO in 22 patients (mean age 69 +/- 5 years, 17 males) were included. All patients had undergone MSCT prior to PCI. Images were analyzed for lesion visibility and plaque characteristics of CTO. The presence and location of calcified plaque within the CTO were systematically assessed. Each lesion was classified as a noncalcified, moderately calcified, or exclusively calcified plaque. Procedural failure was defined as the inability to cross a guide wire through the occlusion. All coronary routes of CTO segment were visualized. MSCT revealed three markedly bent CTO segments (13.0%), which could not be identified by coronary angiography only. Calcified plaques were detected in 30 lesions of 19 CTO segments (82.6%), but were not detected in the other four. The majority of calcified plaque was located in the proximal lesion, or both proximal and distal lesions. Fifteen out of 30 calcified lesions (50.0%) were exclusively calcified plaques. Overall procedural success was obtained in 21 CTOs (91.3%). MSCT can accurately identify the route of the CTO segment and evaluate both distribution and amount of the calcified plaque within it. Even with the complicated and/or calcified lesions, PCI success rate was excellent under MSCT guidance. MSCT should become a useful tool in PCI of CTO.     

The predictors of successful percutaneous coronary intervention in ostial left anterior descending artery chronic total occlusion

Background: Percutaneous coronary intervention (PCI) to chronic total occlusion (CTO) has become one of the treatment strategies in recent era. The ostium of the left anterior descending artery (LAD) is one of the most difficult positions for CTO revascularization. Until now, limited data has been made available for the prediction of successful ostial LAD CTO PCI. Objective: The aim of the study was to compare the differences between ostial LAD and all other CTOs and to identify the predictors of successful ostial LAD CTO PCI. Methods: This retrospective analysis included consecutive patients referred for CTO PCI between January 2001 and September 2013. Ostial LAD CTO was defined as CTO at the position whose distance between lesion and left main bifurcation was less than 1 mm. Baseline demographics, lesion characteristics, interventional procedure details, and devices were compared between the ostial LAD group and the all other CTOs group. The predictors of successful ostial LAD CTO PCI were also evaluated. Results: 621 patients who underwent CTO PCI were enrolled retrospectively to this study. A total of 70 patients of ostial LAD CTO were compared with 551 patients of all other CTOs group in this study. Ostial LAD CTO was found to have more bridging and better collaterals than all other CTOs. Procedure time, fluoroscopic time, contrast volumes, the use of contralateral injection, and the use of the retrograde approach were significantly greater in the ostial LAD CTO group. The ostial LAD CTO group also had significantly higher J‐CTO scores (2.7 ± 0.8 vs. 2.2 ± 1.1, P = 0.011) and higher Syntax Scores (28.3 ± 6.5 vs. 20.9 ± 9.7, P < 0.001). A slightly lower final success rate, but statistically non‐significant, was observed in the ostial LAD CTO group (80.0% vs. 81.9%, P = 0.706). Univariate and multivariate logistic regression revealed that without antegrade failure and with retrograde success were predictors of the success of ostial LAD CTO PCI. Syntax Score was also capable of predicting the ostial LAD CTO PCI outcome. J‐CTO score was not found to be associated with final success for ostial LAD CTO patients. Conclusions: Ostial LAD CTO resulted in higher lesion complexity in J‐CTO scores and Syntax Scores. Ostial LAD CTO PCI had a slightly lower final success rate than that of all other CTOs PCI with longer procedure duration, fluoroscopic time and larger contrast volume. Without antegrade failure, with retrograde success, and lower Syntax Score were found to predict the success of ostial LAD CTO PCI. © 2014 Wiley Periodicals, Inc.     

Effectiveness,safety, and patient reported outcomes of a planned investment procedure in higher-risk chronic total occlusion percutaneous coronary intervention: Rationale and design of the invest-CTO study

Background

The anatomical complexity of a chronic total occlusion (CTO) correlates with procedural failure and complication rates. CTO modification after unsuccessful crossing has been associated with subsequent higher technical success rates, but complication rates remain high with this approach. While successful CTO percutaneous coronary intervention (PCI) has been associated with improved angina and quality of life (QOL) this has not been demonstrated in anatomically high-risk CTOs. Whether a planned CTO modification procedure, hereafter named Investment procedure, could improve patient outcomes has never been investigated.

Study Design

Invest-CTO is a prospective, single-arm, international, multicenter study, evaluating the effectiveness and safety of a planned investment procedure, with a subsequent completion CTO PCI (at 8–12 weeks), in anatomically high-risk CTOs. We will enroll 200 patients with CTOs defined as high-risk according to our Invest CTO criteria at centers in Norway and United Kingdom. Patients with aorto-ostial lesions, occlusion within a previous stent, or a prior attempt at target vessel CTO PCI within 6 months will be excluded. The co-primary endpoints are cumulative procedural success (%) after both procedures, and a composite safety endpoint at 30 days after completion CTO PCI. Patient reported outcomes (PROs), treatment satisfaction, and clinical endpoints will be reported.

Conclusion

This study will prospectively evaluate the effectiveness and safety of a planned two staged PCI procedure in the treatment of high-risk CTOs and may have the potential to change current clinical practice.     

Collateral grading systems in retrograde percutaneous coronary intervention of chronic total occlusions

Background

The Japanese Channel (J-Channel) score was introduced to aid in retrograde percutaneous coronary intervention (PCI) of chronic total coronary occlusions (CTOs). The predictive value of the J-Channel score has not been compared with established collateral grading systems such as the Rentrop classification and Werner grade.

Aims

To investigate the predictive value of the J-Channel score, Rentrop classification and Werner grade for successful collateral channel (CC) guidewire crossing and technical CTO PCI success.

Methods

A total of 600 prospectively recruited patients underwent CTO PCI. All grading systems were assessed under dual catheter injection. CC guidewire crossing was considered successful if the guidewire reached the distal segment of the CTO vessel through a retrograde approach. Technical CTO PCI success was defined as thrombolysis in myocardial infarction flow grade 3 and residual stenosis <30%.

Results

Of 600 patients, 257 (43%) underwent CTO PCI through a retrograde approach. Successful CC guidewire crossing was achieved in 208 (81%) patients. The predictive value of the J-Channel score for CC guidewire crossing (area under curve 0.743) was comparable with the Rentrop classification (0.699, p = 0.094) and superior to the Werner grade (0.663, p = 0.002). Technical CTO PCI success was reported in 232 (90%) patients. The Rentrop classification exhibited a numerically higher discriminatory ability (0.676) compared to the J-Channel score (0.664) and Werner grade (0.589).

Conclusions

The J-channel score might aid in strategic collateral channel selection during retrograde CTO PCI. However, the J-Channel score, Rentrop classification, and Werner grade have limited value in predicting technical CTO PCI success.     

Drug‐coated balloon after subintimal plaque modification in failed coronary chronic total occlusion percutaneous coronary intervention: A novel concept

Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) is a technically challenging procedure. In failed cases, plaque modification strategy (also known as “investment procedure”), defined as the intentional dilation of the subintimal space through the CTO segment, can be applied. The typical dilation device used in this strategy is a regular angioplasty balloon (either semi‐ or noncompliant). Performing this technique with a drug‐coated balloon (DCB) may facilitate a staged procedure by promoting a better vessel healing. Herein, we present three cases of failed CTO PCI, managed with DCB plaque modification, and their follow‐up staged procedure.     

Intravascular lithotripsy assisted chronic total occlusion revascularization with reverse controlled antegrade retrograde tracking

Advances in percutaneous coronary intervention (PCI) techniques in chronic total occlusion (CTO) procedures have improved the success of this procedure. CTO PCI via the retrograde approach are facilitated most frequently by reverse controlled antegrade/retrograde tracking (R‐CART). This aims to create a communication between the proximal and distal lumens, which may be achieved between intimal and subintimal spaces. In patients with calcified coronary vessels, creating sufficient disruptions to connect these spaces can be challenging. Intravascular lithotripsy (IVL) has become a useful tool to modify intracoronary calcification for stent deployment and expansion. This case demonstrates the utility of IVL in facilitating connection in R‐CART to complete the CTO PCI where heavy calcification was present at the site of chronic occlusion.     

CTO recanalization by intraocclusion injection of contrast: The microchannel technique

Objectives : To assess the utilization of microinjection of contrast for the recanalization of chronic total occlusions (CTO). Background : Microchannels in CTOs have been considered important conduits for CTO crossing, utilizing dedicated guidewires. We postulated that microinjection of contrast immediately distal to the proximal cap of the CTO could identify and enlarge these microvessels, creating a passage for crossing the CTO with a floppy guidewire. Methods : A total of 32 patients with a CTO were treated with this technique. Following few millimetres penetration of the proximal fibrous cap of the occlusion with a dedicated CTO guidewire, the over‐the‐wire balloon was advanced into the proximal portion of the occlusion, and 50–100 μg of nitroglycerine followed by 1 ml of contrast was gently injected into the occluded segment. Technical success of the microchannel technique was defined as the ability to visualize the distal true lumen with microinjection of contrast and thereafter cross the CTO with a floppy guidewire in the absence of any dissection. Results : Overall, technical success of the microchannel technique was obtained in 20 (63%) with angiographic success in 19. In 12 (37%) cases there was a technical failure because of dissection, and we obtained recanalization of the artery in 7 of these 12 cases with another technique. There was only one case of periprocedural myocardial infarction in an unsuccessful procedure and no major adverse cardiac events or subacute stent thromboses were observed. Conclusions : Microinjection of contrast immediately distal to the proximal fibrous cap of a CTO may be an additional technique to facilitate recanalization of CTO. © 2008 Wiley‐Liss, Inc.     

CT coronary angiography predicts the outcome of percutaneous coronary intervention of chronic total occlusion

BACKGROUND: The success rate of percutaneous coronary intervention (PCI) of chronic total occlusions (CTO) is relatively low. Further evaluation of CTO lesion with CT coronary angiography (CT-CA) may help to better select patients that would benefit from percutaneous revascularization. We aimed to test the possible association between failed PCI and transluminal calcification of CTO as assessed by CT-CA. METHODS: Patients with CTO awaiting PCI were scanned with a 16-slice CT. A cardiologist and a radiologist assessed transluminal calcification of CTO lesions on CT images while an interventional cardiologist at a core laboratory assessed conventional variables of invasive fluoroscopic coronary angiography (FCA) associated with failed PCI of CTO. The significance of CT and FCA variables in association with failed PCI were analyzed. RESULTS: In a cohort of 39 patients with 43 CTO lesions, 24 lesions were successfully revascularized. Transluminal calcification > or =50% as assessed on CT-CA was strongly associated with failed PCI (odds ratio [OR] of PCI success = 0.10, 95% confidence interval [CI]: 0.02-0.47, P = 0.003). Blunt stump as seen on FCA was also associated with failed PCI (OR of PCI success = 0.24, 95% CI: 0.07-0.86, P = 0.029). There was no significant evidence to support that the duration of CTO, presence of side branch and bridging collaterals, and the absence of microchannels as assessed with FCA were associated with failed PCI. On multivariate analysis, transluminal calcification > or =50% on CT-CA was the only significant predictor of failed PCI. CONCLUSIONS: Heavy transluminal calcification as assessed with CT-CA is an independent predictor of failed PCI of CTO. CT-CA may have a role in the work-up of CTO patients prior to PCI.     

Procedural implications of intravascular ultrasound morphologic features of chronic total coronary occlusions

Although the success rates of percutaneous coronary intervention of chronic total occlusions (CTOs) have improved, morphologic features are not well known. We analyzed experience at 4 centers where intravascular ultrasound (IVUS) was performed in 67 native artery CTO lesions (mean CTO duration 6.3 months) just after the lesion was crossed with a guidewire (n = 7) or after dilatation with a 1.5-mm (n = 46) or 2.0-mm (n = 14) balloon. IVUS detected calcium somewhere in the CTO in 96%; however, only 68% had mild calcium. IVUS identified a proximal end of the CTO in all lesions, but a distal end of the CTO in only 50%. An intramural hematoma was observed in 34% of CTOs, suggesting that the guidewire frequently entered the medial space during successful recanalization. CTOs were longer, vessel area was smaller, and total calcium index was greater in lesions with hematomas (p = 0.003, 0.05, and 0.03, respectively). Inadequate reflow after the procedure was observed in 9% and was associated with longer lesions and intralesional calcium. CTO length as measured with angiography was shorter than the length as measured with IVUS (p = 0.02). Calcium was detected on the angiogram in 61% (p = 0.054 vs IVUS). Most typical angiographic findings associated with a low rate of procedural success were not associated with different IVUS morphologies. In conclusion, CTO lesions had multiple small calcium deposits, intramural hematomas were common and were indicative of guidewire penetration into the medial space during the CTO procedure, especially in long calcified lesions in smaller vessels, and inadequate reflow after the procedure was correlated with more complex CTO morphology.