Advances in percutaneous coronary intervention for chronic total occlusions: current antegrade dissection and reentry techniques and updated algorithm

Percutaneous coronary intervention (PCI) for chronic total occlusions (CTO) is considered relatively complex with low success rates and high complication rates. Treating a CTO with PCI using the hybrid algorithm increases success rates with acceptable complication rates. An essential part of the hybrid algorithm is antegrade dissection and reentry (ADR). In PCI of a non-CTO coronary lesion, the guidewire over which the stent is advanced and placed stays within the true lumen of the coronary artery. ADR techniques make it possible to cross the lesion through the wall of the coronary artery, the subintimal space, thus creating a small bypass within the architecture of the coronary artery and restoring antegrade blood flow. ADR increases success rates, especially in more difficult CTO procedures. In the last decade, new materials and techniques have been introduced in quick succession, which are summarised in this review. Consequently an updated ADR algorithm is presented, which can support the CTO operator during an ADR procedure.

     

Coronary physiology before and after chronic total occlusion treatment: what does it tell us?

Studies performed in the last two decades demonstrate that after successful percutaneous coronary intervention (PCI) of a chronically occluded coronary artery, the physiology of the chronic total occlusion (CTO) vessel and dependent microvasculature does not normalise immediately but improves significantly over time. Generally, there is an increase in fractional flow reserve (FFR) in the CTO artery, a decrease in collateral blood supply and an increase in FFR in the donor artery accompanied by an increase in blood flow and decrease in microvascular resistance in the myocardium supplied by the CTO vessel. Analogous to these physiological changes, positive remodelling of the distal CTO artery also occurs over time, and intravascular imaging can be helpful for analysing distal vessel parameters. Follow-up coronary angiography with physiological measurements after several weeks to months can be helpful and informative in a subset of patients in order to decide upon the necessity for treatment of residual coronary artery stenosis in the vessel distal to the CTO or in the contralateral donor artery, as well as in deciding whether stent optimisation is indicated. We suggest that such physiological guidance of CTO procedures avoids unnecessary overtreatment during the initial procedure, guides interventions at follow-up, and improves our understanding of what PCI in CTO means.

     

Chronic Total Occlusions in Sweden – A Report from the Swedish Coronary Angiography and Angioplasty Registry (SCAAR)

Introduction

Evidence for the current guidelines for the treatment of patients with chronic total occlusions (CTO) in coronary arteries is limited. In this study we identified all CTO patients registered in the Swedish Coronary Angiography and Angioplasty Registry (SCAAR) and studied the prevalence, patient characteristics and treatment decisions for CTO in Sweden.

Methods and Results

Between January 2005 and January 2012, 276,931 procedures (coronary angiography or percutaneous coronary intervention) were performed in 215,836 patients registered in SCAAR. We identified all patients who had 100% luminal diameter stenosis known or assumed to be ≥3 months old. After exclusion of patients with previous coronary artery bypass graft (CABG) surgery or coronary occlusions due to acute coronary syndrome, we identified 16,818 CTO patients. A CTO was present in 10.9% of all coronary angiographies and in 16.0% of patients with coronary artery disease. The majority of CTO patients were treated conservatively and PCI of CTO accounted for only 5.8% of all PCI procedures. CTO patients with diabetes and multivessel disease were more likely to be referred to CABG.

Conclusion

CTO is a common finding in Swedish patients undergoing coronary angiography but the number of CTO procedures in Sweden is low. Patients with CTO are a high-risk subgroup of patients with coronary artery disease. SCAAR has the largest register of CTO patients and therefore may be valuable for studies of clinical importance of CTO and optimal treatment for CTO patients.     

Recanalisation of coronary chronic total occlusions with new techniques including the retrograde approach via collaterals

Objective

Percutaneous treatment of coronary chronic total occlusions (CTO) remains one of the major challenges in interventional cardiology. The strategies of recanalisation in CTO have changed drastically due the development of new techniques such as the retrograde approach via collaterals. In this single-centre experience we sought to analyse the success rates with the use of different CTO techniques, the complication rates, and we evaluated predictors of failed CTO recanalisation attempts.

Methods and Results

In this single-centre observational study we analysed the prospectively entered data of 331 consecutive patients, undergoing percutaneous coronary intervention (PCI) for CTO in 338 lesions at the Heart Center Wuppertal between June 2007 and July 2010. Nineteen lesions were attempted twice and one lesion three times (=358 procedures). The lesion-related success rates were 81.1%. Single-wire usage was the predominant strategy used in 198 antegrade cases (65.6%) followed by parallel wire technique and see-saw technique in 94 cases (31.1%). In the retrograde procedures, the reverse CART technique was predominantly used (35.7%), followed by retrograde wire passage (17.9%), marker wire (17.9%) and CART (14.3%). The in-hospital complications were low and comparable with conventional PCI data. The presence of blunt stump, severe calcification, severe tortuosity and occlusion length >30 mm were independent predictors of procedural failure.

Conclusions

A high degree of success with low in-hospital complications comparable with conventional PCI data can be expected in the hands of experienced CTO operators. A second try with a retrograde approach after antegrade failure should be considered.     

冠状动脉CTA结合动态心电图夜间ST段趋势图诊断冠状动脉硬化性心脏病的价值研究

摘要 目的：探讨冠状动脉CTA结合动态心电图夜间ST段趋势图对冠状动脉硬化性心脏病（冠心病）的诊断价值。方法：回顾性分析2022年1月-2023年2月在我院疑似冠心病的患者104例,所有患者均行冠状动脉造影、冠状动脉CTA、动态心电图及临床相关实验室检查。以冠状动脉造影结果作为诊断冠心病的金标准,分析比较冠状动脉CTA、动态心电图夜间ST段趋势图及两者联合诊断冠心病的诊断效能和一致性。结果：104例疑似冠心病的患者确诊93例（89.42%）。冠状动脉CTA诊断冠心病的敏感性为90.32%,特异性为72.73%,阳性预测值为96.55%,阴性预测值为47.06%,准确率为88.46%,与冠状动脉造影的Kappa值为0.813,一致性好。动态心电图夜间ST段趋势图诊断冠心病的敏感性为84.95%,特异性为63.64%,阳性预测值为95.18%,阴性预测值为33.33%,准确率为82.69%,与冠状动脉造影的Kappa值为0.724,一致性较好。有夜间ST段动态改变的冠心病检出率（84.95%,79/93）明显高于无夜间ST段动态改变的冠心病检出率（15.05%,14/93）,差异有统计学意义（P＜0.001）。冠状动脉CTA结合动态心电图夜间ST段趋势图诊断冠心病的敏感性为96.77%,特异性为90.91%,阳性预测值为98.90%,阴性预测值为76.92%,准确率为96.15%,与冠状动脉造影的Kappa值为0.923,一致性好。结论：冠状动脉CTA结合动态心电图夜间ST段趋势图诊断冠心病的临床价值优于冠状动脉CTA或动态心电图夜间ST段趋势图单独检查。     

Hemodynamics analysis of the serial stenotic coronary arteries

Coronary arterial stenoses, particularly serial stenoses in a single branch, are responsible for complex hemodynamic properties of the coronary arterial trees, and the uncertain prognosis of invasive intervention. Critical information of the blood flow redistribution in the stenotic arterial segments is required for the adequate treatment planning. Therefore, in this study, an image based non-invasive functional assessment is performed to investigate the hemodynamic significances of serial stenoses. Twenty patient-specific coronary arterial trees with different combinations of stenoses were reconstructed from the computer tomography angiography for the evaluation of the hemodynamics. Our results showed that the computed FFR based on CTA images (FFRCT) pullback curves with wall shear stress (WSS) distribution could provide more effectively examine the physiological significance of the locations of the segmental narrowing and the curvature of the coronary arterial segments. The paper thus provides the diagnostic efficacy of FFRCT pullback curve for noninvasive quantification of the hemodynamics of stenotic coronary arteries with serial lesions, compared to the gold standard invasive FFR, to provide a reliable physiological assessment of significant amount of coronary artery stenosis. Further, we were also able to demonstrate the potential of carrying out virtual revascularization, to enable more precise PCI procedures and improve their outcomes.     

冠状动脉CTA和DSA对冠心病患者的临床诊断价值比较

目的:比较冠状动脉CT血管成像(CT angiography,CTA)以及数字减影血管造影(digital subtraction angiography,DSA)诊断冠心病的临床价值差异。方法:选择2013年12月至2020年3月安徽医科大学第三附属医院、安徽医科大学第四附属医院收治的60例冠心病患者为研究对象,首先对其实施多排螺旋CT冠状动脉血管造影检测(CTA),而后2 w内再对其实施DSA检测,比较两种检测方式对不同血管狭窄程度、不同性质斑块检出率的差异,最后以DSA检测结果为金标准,评估CTA对冠状动脉狭窄诊断的一致性、灵敏度、特异度、阳性预测值和阴性预测值。结果:(1)CTA检测狭窄血管共计387支,轻度狭窄152支(39.28%),中度狭窄118支(30.49%),重度狭窄105支(27.13%),闭塞12支(3.10%);DSA检测狭窄血管392支,轻度狭窄150支(38.27%),中度狭窄124支(31.63%),重度狭窄112支(28.57%),闭塞6支(1.53%),两组各血管狭窄类型比较差异无统计学意义(P0.05);(2)CTA检测斑块69个,其中钙化斑43个(62.32%),非钙化斑26个(37.68%),DSA检测斑块61个,其中钙化斑33个(54.10%),非钙化斑28个(45.50%),两种检测方式差异无统计学意义(P0.05);(3)以DSA检测为金标准,CTA对重度及以上血管狭窄诊断一致性为99.23%,特异度为98.31%,灵敏度为99.64%,阳性预测值为99.15%,阴性预测值为99.27%。结论:与DSA相比,CTA对冠心病患者血管狭窄的诊断价值相当,且属于无创检测,在冠心病早期筛查中临床应用价值更高。     

Development and first results of a dedicated chronic total occlusion programme

Objective

To describe the development and first results of a dedicated chronic total occlusion (CTO) programme in a tertiary medical centre.

Background

Because of the complexity and the increased risk of complications during percutaneous coronary intervention (PCI) for CTO, it is essential that less experienced and evolving CTO centres perform regular quality analyses.

Methods

We therefore performed analyses to describe the results during the first 3 years of a dedicated CTO programme at a high-volume PCI centre. In addition, we discuss the strategies employed to develop such a programme.

Results

A total of 179 consecutive patients undergoing 187 CTO procedures were included in the study. The complexity of the CTO lesions increased from a mean J‑CTO (Japanese Multicentre CTO Registry) score of 1.3 in 2015 to 2.1 in 2017. In the majority of cases, the antegrade wire escalation technique was performed. Final technical success rate was 78.5% in 175 patients with a single CTO and 80.2% of all 187 CTO procedures. No peri-procedural or in-hospital deaths occurred. One peri-procedural myocardial infarction occurred. Cardiac tamponade occurred in 2 cases, both managed by pericardiocentesis. No urgent cardiac surgery was necessary. Survival and revascularisation rates at 30 days and 1 year were excellent.

Conclusion

Following initiation of a dedicated CTO programme, using up-to-date techniques and strategies, procedural and clinical outcome were comparable with current standards in established centres.

     

Coronary computed tomography angiography and [15O]H2O positron emission tomography perfusion imaging for the assessment of coronary artery disease

Determining the anatomic severity and extent of coronary artery disease (CAD) by means of coronary computed tomography angiography (CCTA) and its effect on perfusion using myocardial perfusion imaging (MPI) form the pillars of the non-invasive imaging assessment of CAD. This review will 1) focus on CCTA and [¹⁵O]H₂O positron emission tomography MPI as stand-alone imaging modalities and their combined use for detecting CAD, 2) highlight some of the lessons learned from the PACIFIC trial (Comparison of Coronary CT Angiography, SPECT, PET, and Hybrid Imaging for Diagnosis of Ischemic Heart Disease Determined by Fractional Flow Reserve (FFR) (NCT01521468)), and 3) discuss the use of [¹⁵O]H₂O PET MPI in the clinical work-up of patients with a chronic coronary total occlusion (CTO).

     

冠状动脉CTA联合血清HCY、Cys-C、ApoB/ApoA1比值对2型糖尿病患者合并冠状动脉病变的诊断价值

摘要 目的：探究冠状动脉CT血管造影（CTA）联合血清同型半胱氨酸（HCY）、胱抑素C（Cys-C）、载脂蛋白B/载脂蛋白A1（ApoB/ApoA1）比值对2型糖尿病（T2DM）患者合并冠状动脉病变的诊断价值。方法：回顾性选取2018年8月到2021年8月间我院收治的358例T2DM患者,均行常规生化指标、CTA检查、冠状动脉造影（CAG）检查,根据CAG检查结果为金标准将T2DM患者分为未合并冠脉病变组（190例）和合并冠脉病变组（168例）,比较两组血清HCY、Cys-C、ApoB/ApoA1比值,分析CTA与CAG诊断冠脉狭窄结果的一致性,应用受试者工作特征（ROC）曲线评估冠状动脉CTA联合血清HCY、Cys-C、ApoB/ApoA1比值对T2DM合并冠状动脉病变的诊断价值。结果：与未合并冠脉病变组比较,合并冠脉病变组血清HCY、Cys-C、ApoB、ApoB/ApoA1比值水平明显更高（P＜0.05）,ApoA1明显更低（P＜0.05）。以CAG为金标准,CTA诊断冠脉狭窄程度与CAG一致性较高（Kappa值0.748）。ROC曲线评估冠状动脉CTA诊断T2DM合并冠脉病变的AUC、灵敏度、特异度、准确度依次为0.802、74.40%、83.71%、79.11%。三项血清指标联合AUC、准确度显著优于单一指标（P＜0.05）。冠状动脉CTA联合血清HCY、Cys-C、ApoB/ApoA1比值诊断T2DM合并冠脉病变的价值显著优于各项指标单一诊断或三项血清指标联合诊断（P＜0.05）。结论：冠状动脉CTA联合血清HCY、Cys-C、ApoB/ApoA1比值诊断T2DM患者合并冠状动脉病变的价值较高,相较各项指标单一应用而言更具优势。     

Patients with coronary stenosis and a fractional flow reserve of ≥0.75 measured in daily practice at the VU University Medical Center

Objectives. The aim of this study was to analyse the rate of major adverse clinical events in patients with coronary artery disease and a fractional flow reserve (FFR) of ≥0.75 and deferred for coronary intervention in daily practice. Methods. From 1 January to 31 December 2006, FFR measurement was initiated in 122 patients (5%) out of 2444 patients referred for coronary angiography. In two patients FFR measurement failed and in one patient the FFR value could no longer be traced in the documents. Thus, 119 patients (84 men, 64 years, range 41-85) were included in the evaluation (145 lesions). Major adverse clinical events (death, myocardial infarction, percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG)) and the presence of angina were evaluated at follow-up. Furthermore a cost-effectiveness analysis was performed. Results. In 93 patients (76%) the FFR value was ≥0.75. Seventy of these 93 patients (76%) were treated with medication alone or underwent PCI for a different lesion (medical treatment group). Average duration of follow-up of all 119 patients was 22 months (range 4 days to 30 months). In the medical treatment group seven patients (10%) experienced a major adverse clinical event related to the FFR-evaluated lesion during follow-up. In this study population, the use of FFR measurement is cost-reducing provided that at least 65% of the patients in the medical treatment group has had a PCI with stent implantation when the use of FFR measurement is impossible. In this case, the decision to use PCI with stent implantation is purely based on the angiogram. Conclusions. In patients with a coronary stenosis based on visual assessment and an FFR of ≥0.75 deferral of PCI or CABG is safe in daily clinical practice and saves money. (Neth Heart J 2010;18:402-7.)     

冠状动脉CT造影对冠心病的临床诊断价值研究

目的:探讨研究冠状动脉CT造影检查对冠心病的临床诊断价值。方法:收集我院2012年1月至2013年10月共计70例临床怀疑为冠心病的患者,对这些患者分别进行冠状动脉CT造影检查和数字减影冠状动脉造影(DSA)检查,记录这两项检查所得结果及数据,以检查数据为基础对冠状动脉CT造影和数字减影冠状动脉造影检查的临床实验效果进行对比研究。结果:70例病人均可顺利完成以上两种检查,按照数字减影冠状动脉造影检查的标准,冠状动脉CT造影的敏感度为92.2%,特异度为97.4%、阳性预测率为90.5%、阴性预测率98%。结论:相对于数字减影冠状动脉造影检查,冠状动脉CT造影检查是一种更加安全、可靠、无创且更具临床指导意义的检测技术,因此可以推荐作为冠心病诊断的首选方法。     

心肌酶谱、动态心电图及冠状动脉CT血管造影诊断嗜铬细胞瘤儿茶酚胺性心脏损害价值研究

摘要 目的：探讨心肌酶谱、动态心电图及冠状动脉CT血管造影诊断嗜铬细胞瘤儿茶酚胺性心脏损害的临床价值。方法：收集2013年1月-2020年4月在我院诊断为嗜铬细胞瘤患者114例,其中嗜铬细胞瘤儿茶酚胺性心脏损害的患者27例。所有患者均完善术前常规检查（血常规、胸片、动态心电图）、心肌酶谱、心脏超声、冠状动脉CTA等临床资料,并收集患者一般临床资料,如血压、临床症状等。结果：114例嗜铬细胞瘤患者中,27例患者存在嗜铬细胞瘤儿茶酚胺性心脏损害。嗜铬细胞瘤儿茶酚胺性心脏损害患者一般临床资料与嗜铬细胞瘤无儿茶酚胺性心脏损害的患者差异无统计学意义（P＞0.05）。嗜铬细胞瘤儿茶酚胺性心脏损害以高血压为主要表现,临床症状表现多样,可伴有头痛、心悸、多汗三联征表现。114例患者中,26例患者出现心肌酶谱升高,36例患者存在不同程度的心电图异常、24例患者冠状动脉CTA异常,嗜铬细胞瘤儿茶酚胺性心脏损害患者在心肌酶谱、动态心电图及冠状动脉CTA异常例数与嗜铬细胞瘤无儿茶酚胺性心脏损害患者中差异均有统计学意义（P＜0.05）。114例患者中心肌酶谱或心电图或冠状动脉CTA异常的患者总共56例,其中嗜铬细胞瘤儿茶酚胺性心脏损害患者23例,嗜铬细胞瘤无儿茶酚胺性心脏损害患者有33例,差异有统计学意义（P＜0.05）。嗜铬细胞瘤儿茶酚胺性心脏损害患者中,心律失常最为常见。结论：嗜铬细胞瘤儿茶酚胺性心脏损害患者心肌酶谱、动态心电图及冠状动脉CTA均可存在异常表现,但特异性、敏感性不高,三者同时综合分析可以提高临床诊断。     

Incidence and outcomes of chronic total occlusion percutaneous coronary intervention in the Netherlands: data from a nationwide registry

Background

Patients with chronic total coronary occlusions (CTO) are at increased risk for poor clinical outcomes. We aimed to determine the incidence of CTO percutaneous coronary intervention (PCI) and to identify CTO patients at risk for cardiac events in the nationwide Netherlands Heart Registration (NHR).

Methods

We included all PCI procedures with ≥1 CTO registered in the NHR from January 2015 to December 2018, excluding acute interventions. We used multivariable logistic regression of baseline characteristics to calculate the risk for events as odds ratios (OR) with 95% confidence intervals (CI).

Results

Of the PCIs performed during the study period, 6.3% (8,343/133,042) were for CTOs, with the percentage increasing significantly over time from 5.9% in 2015 to 6.6% in 2018 (p < 0.001). Coronary artery bypass grafting <24 h was carried out in 0.3%, and the only significant predictor was diabetes mellitus (OR 2.97, 95% CI 1.04–8.49, p = 0.042). Myocardial infarction (MI) <30 days occurred in 0.5%, and renal insufficiency (i.e. estimated glomerular filtration rate <30 ml/min per 1.73 m²) was identified as an independent predictor (OR 4.70, 95% CI 1.07–20.61, p = 0.040). Among patients undergoing CTO-PCI, 1‑year mortality was 3.7%, and independent predictors included renal insufficiency (OR 5.59, 95% CI 3.25–9.59, p < 0.001), left ventricular ejection fraction <30% (OR 3.43, 95% CI 2.00–5.90, p < 0.001), previous MI (OR 1.62, 95% CI 1.14–2.31, p = 0.007) and age (OR 1.06 per year increment, 95% CI 1.04–1.07, p < 0.001). Target-vessel revascularisation <1 year occurred in 11.3%.

Conclusion

CTO-PCI is still infrequently performed in the Netherlands. The most important predictor of mortality after CTO-PCI was renal insufficiency. Identification of patients at risk may help improve the prognosis of CTO patients in the future.

     

经桡动脉和经股动脉途径PCI治疗冠状动脉慢性闭塞性病变的可行性和安全性比较

目的:比较经股动脉和经桡动脉途径介入治疗冠状动脉慢性闭塞性病变的可行性和安全性。方法:选择2011年1月至2012年8月南京市第一医院收治的325例因为冠状动脉慢性闭塞性病变行经皮冠状动脉介入治疗的患者为研究对象,根据手术途径分为经桡动脉治疗(n=211)和经股动脉(n=114)组,回顾性分析和比较患者的基线特征、病变特征、手术经过和手术相关并发症。结果:经桡动脉和经股动脉组手术成功率分别为79.62%和80.70%(P0.05)。两组患者的性别、年龄、危险因素(高血压、糖尿病及高脂血症)以往PCI及CABG手术史及冠心病临床表现比较均无统计学差别(均P0.05);两组患者的慢性闭塞性病变病变数量、术中主动脉内球囊反搏(intra-aortic balloon pump,IABP)使用率、术后TIMI血流、手术时间、冠状动脉穿孔并发症的发生率比较无统计学差别(均P0.05),但经股动脉手术组较经桡动脉组术中血管内超声(intravascular ultrasound,IVUS)的使用率更高(57.01%vs45.02%,P=0.039)。结论:经桡动脉PCI治疗冠状动脉慢性闭塞性病变更安全、有效,其IVUS的使用率低于经股动脉PCI治疗,但对于复杂慢性闭塞性病变病变术者可能更倾向于采用经股动脉途径。     

冠状动脉CT造影对冠心病的临床诊断价值研究

目的：探讨研究冠状动脉CT造影检查对冠心病的临床诊断价值。方法：收集我院2012年1月至2013年10月共计70例临床怀疑为冠心病的患者,对这些患者分别进行冠状动脉CT造影检查和数字减影冠状动脉造影（DSA）检查,记录这两项检查所得结果及数据,以检查数据为基础对冠状动脉CT造影和数字减影冠状动脉造影检查的临床实验效果进行对比研究。结果：70例病人均可顺利完成以上两种检查,按照数字减影冠状动脉造影检查的标准,冠状动脉CT造影的敏感度为92.2%,特异度为97.4%、阳性预测率为90.5%、阴性预测率98%。结论：相对于数字减影冠状动脉造影检查,冠状动脉CT造影检查是一种更加安全、可靠、无创且更具临床指导意义的检测技术,因此可以推荐作为冠心病诊断的首选方法。     

Association between cardiovascular disease and a history of cancer in patients with chest pain on the fast track outpatient clinic

Background

The purpose of this study is to investigate the prevalence of a history of malignancy in patients with chest pain who were referred for computed tomography angiography as well as the long-term survival and cardiovascular outcomes, including coronary artery disease (CAD) and coronary artery calcium (CAC) percentiles of cancer survivors. These data are relevant since it is unknown how cancer survivors, who underwent cardio-toxic therapies, should be monitored.

Methods

We analysed all patients with chest pain, who came to the outpatient clinic and underwent computed tomography angiography. The primary study endpoint was long-term survival. The secondary endpoints included CAD on computed tomography angiogram (CTA), CAC percentiles, suspected and confirmed malignancy on CTA, and other accidental findings on CTA.

Results

Of all 1,892 patients included in the analyses, 133 (7%) had a history of malignancy and 1,759 (93%) did not. Mortality rates were higher for the cancer survivors (6.5% vs 20.9% after ten years, p < 0.001). The multivariable Cox regression model also showed higher mortality for cancer survivors after ten years (adjusted hazard ratio 2.48 [95% confidence interval: 1.58–3.90]). CAD did not differ between both groups. CAC percentiles were higher in cancer survivors (p = 0.037). Cancer survivors had more suspected malignancies (3.8% vs 0.5%; p = 0.001) and also more confirmed malignancies on CTA (3.0% vs 0.1%; p < 0.001).

Conclusions

Cancer survivors have higher mortality rates, no difference in CAD on CTA, higher CAC percentiles and more often malignancy on CTA compared with patients without a cancer history.

     

Coronary Computed Tomography Angiography Based Assessment of Endothelial Shear Stress and Its Association with Atherosclerotic Plaque Distribution In-Vivo

Purpose

The relationship between low endothelial shear stress (ESS) and coronary atherosclerosis is well established. ESS assessment so far depended on invasive procedures. The aim of this study was to demonstrate the relationship between ESS and coronary atherosclerosis by using non-invasive coronary computed tomography angiography (CTA) for computational fluid dynamics (CFD) simulations.

Methods

A total number of 7 consecutive patients with suspected coronary artery disease who received CTA and invasive angiography with IVUS analysis were included in this study. CTA examinations were performed using a dual-source scanner. These datasets were used to build a 3D mesh model. CFD calculations were performed using a validated CFD solver. The presence of plaque was assumed if the thickness of the intima-media complex exceeded 0.3 mm in IVUS. Plaque composition was derived by IVUS radiofrequency data analysis.

Results

Plaque was present in 32.1% of all analyzed cross-sections. Plaque prevalence was highest in areas of low ESS (49.6%) and high ESS (34.8%). In parts exposed to intermediate-low and intermediate-high ESS few plaques were found (20.0% and 24.0%) (p<0.001). Wall thickness was closely associated with local ESS. Intima-media thickness was 0.43±0.34mm in low and 0.38±0.32mm in high ESS segments. It was significantly lower when the arterial wall was exposed to intermediate ESS (0.25±0.18mm and 0.28 ± 0.20mm) (p<0.001). Fibrofatty tissue was predominately found in areas exposed to low ESS (p≤0.023).

Conclusions

In this study a close association of atherosclerotic plaque distribution and ESS pattern could be demonstrated in-vivo. Adding CFD analysis to coronary CTA offers the possibility to gather morphologic and physiologic data within one non-invasive examination.     

冠脉护理在320排螺旋CT冠状动脉造影中提高图像质量的作用

目的：探讨320排螺旋CT心脏冠状动脉护理的作用及其临床意义。方法：2009年11月至2010年3月,于我院行心脏检查1024例行320排螺旋CT冠状动脉造影检查的患者,检查前对每一患者进行心理辅导,减轻紧张情绪;进行心率控制、屏气训练等护理措施准备;在扫描过程中配合影像技师使用高压注射器;检查完成后积极与患者交谈,严密观察患者状态,预防造影剂不良反应的发生。结果：受检患者中987例患者顺利完成检查,图像重建后血管显示效果优;16例血管显示良;有1例患者造影剂未全部进入血管内,导致血管显影不充分。有2例出现轻度过敏反应;无空气栓塞或任何心脑血管意外的发生。受检病例中432例同时进行了冠状动脉造影,98%（425/432）与检查结果完全一致,有2%（8/432）与检查结果有轻度误差。结论：检查前细致的护理对提高心脏冠状动脉血管成像成功率、提高至关重要。     

CT检查中造影剂不良反应的预防、处理及对影像学检查 的影响分析

目的：在CT 等医学影像检查过程中,常需要应用造影剂。在造影剂的使用常常发生不良反应,掌握不良反应的发生率,减少 或减轻患者的不良反应,能够使CT 增强扫描顺利进行,提高检查安全性。方法：搜集我院2011 年10 月至2012 年9 月间的1500 例CT 造影增强检查患者,包括冠状动脉CT 血管成像（冠脉CTA）、头部CT 血管成像（头CTA）、肝脏增强、泌尿系三维成像 （CTU）以及双下肢血管成像（双下肢CTA）,进行造影剂的不良反应类型、造影剂药物剂量、注射速度等统计分析,总结造成不良 反应发生的因素及处理方法。结果：不良反应的类型包括发热、呕吐、荨麻疹、面色潮红、局部疼痛、流泪、血压下降、喉头水肿、休 克等。使用非离子型造影剂出现不良反应者85 例,占5.67 %。其中轻度反应65 例,占4. 33%;中度反应16 例,占1.06%;重度4 例,占0. 27 %。结论：在CT 增强扫描过程中,造影剂的用量及注射速度与不良反应的发生有相关性。ＣＴ 检查过程总应该认真 执行操作流程,密切观察病人情况,积极防治,正确处理,将造影剂不良反应降低到最低程度,使患者更加安全。