Optimal cut-off criteria for duplex ultrasound for the diagnosis of restenosis in stented carotid arteries: Review and protocol for a diagnostic study

Background  

Carotid angioplasty with stenting is a relatively new, increasingly used, less-invasive treatment for the treatment of symptomatic carotid artery stenosis. It is being evaluated in ongoing and nearly finished randomized trials. An important factor in the evaluation of stents is the occurrence of in-stent restenosis. An un-stented carotid artery is likely to have a more elastic vessel wall than a stented one, even if stenosis is present. Therefore, duplex ultrasound cut-off criteria for the degrees of an in-stent stenosis, based on blood velocity parameters, are probably different from the established cut-offs used for un-stented arteries. Routine criteria can not be applied to stented arteries but new criteria need to be established for this particular purpose.     

Association between high‐sensitivity C‐reactive protein,lipoprotein‐associated phospholipase A2 and carotid atherosclerosis: A cross‐sectional study

High‐sensitivity C‐reactive protein (hs‐CRP) and lipoprotein‐associated phospholipase A2 (Lp‐PLA2) have been reported to be independent predictors of atherosclerosis. However, whether the combination of these two markers can improve the prediction of atherosclerosis is unknown. This study aimed to evaluate the association between combining hs‐CRP and Lp‐PLA2 and predicting carotid atherosclerosis. A total of 1982 participants aged ≥40 years were included in this study. Hs‐CRP and Lp‐PLA2 were measured by a high‐sensitivity nephelometry assay and quantitative sandwich enzyme‐linked immunosorbent assay, respectively. Ultrasonography was performed on the bilateral carotid arteries to evaluate stenosis and plaques. Multivariable logistic regression models were used to analyse the association between the combination of the hs‐CRP and Lp‐PLA2 levels and carotid plaques and stenosis. A total of 1579 (79.7%) and 181 (9.1%) subjects had carotid plaques and carotid stenosis, respectively. The group with high hs‐CRP and Lp‐PLA2 levels had the highest prevalence of carotid plaques (90.6%) and stenosis (20.8%). A significant association was found between high hs‐CRP and Lp‐PLA2 levels and carotid stenosis (adjusted odds ratio [OR]: 2.39; 95% confidence interval [CI]: 1.13‐5.09), but this combination was not associated with carotid plaques (OR: 2.62, 95% CI: 0.93‐7.38). The results suggested that the combination of hs‐CRP and Lp‐PLA2 were better predictors than either protein alone with regard to carotid atherosclerosis.     

Carotid bruits as predictor for carotid stenoses detected by ultrasonography: an observational study

Background  

Carotid surgery in asymptomatic subjects with carotid stenosis is effective to prevent ischemic stroke. There is, however, uncertainty how to find such persons at risk, because mass screening with carotid artery ultrasonography (US) is not cost-effective. Signs of carotid bruits corresponding to the carotid arteries may serve as a tool to select subjects for further investigation. This study is thus aimed at determining the usefulness of carotid bruits in the screening of carotid stenoses.     

The cardiovascular profile of soccer referees: an echocardiographic study

Background

Previous studies demonstrated a modest association between C-Reactive Protein (CRP), stenosis of carotid artery, and carotid Intima-Media Thickness (IMT) in general population. During present study, we aimed to evaluate the relationship between High Sensitivity C-Reactive Protein (hsCRP) and Common Carotid Intima-Media Thickness (CCIMT) in patients who candidate for Coronary Artery Bypass Grafting (CABG).

Methods

The study subjects were enrolled from patients with coronary arteries disease referred from Shahid Madani Hospital (Tabriz, Iran), who have been candidate for elective CABG from January 2005 to August 2007. The common carotid arteries were evaluated with high-resolution B-mode ultrasonography using a 7.5- MHz linear-array transducer to determine the IMT and grade of stenosis. Serum hsCRP level was measured using commercially available enzyme linked immunosorbent assay kit.

Results

Finally, information of 176 CABG candidates was analysed. The mean age of participants was 62.71 ± 9.45 years with 1.63 male to female ratio. The mean of CCIMT was 0.69 ± 0.54 mm. Although there was no significant correlation between serum hsCRP level and CCIMT in patients without carotid stenosis (p=0.113, r=0.186), participants with common carotid artery stenosis had higher levels of serum hsCRP than participants without stenosis (2.42+/-1.30 vs. 1.20+/-0.97 mg/dl; p=0.009).

Conclusion

Study results showed that there was no correlation between serum hsCRP level and CCIMT in patients without carotid stenosis, but patients with common carotid artery stenosis had higher levels of serum hsCRP than patients without stenosis.     

Delivery and release of nitinol stent in carotid artery and their interactions: a finite element analysis

Carotid angioplasty and stenting (CAS) has emerged as an effective alternative to carotid endarterectomy, and nitinol stents are commonly used in CAS. To evaluate biomechanical properties of nitinol carotid stents and their interactions with carotid arteries, a finite element method (FEM) model was built which is composed of a stenotic carotid tissue, a segmented-design nitinol stent and a sheath. Two different stents were considered to show the influence of stent design on the stent-vessel interactions. Results show that the superelastic stents were delivered into the stenotic vessel lumen through the sheath and self-expanded in the internal and common carotid artery. The stent with shorter struts may have better clinical results and the different stent designs can cause different carotid vessel geometry changes. This FEM can provide a convenient way to test and improve biomechanical properties of existing carotid stents and give clues for new nitinol carotid stent designs.     

The influence of vascular anatomy on carotid artery stenting: A parametric study for damage assessment

Carotid artery stenting is emerging as an alternative technique to surgery for the treatment of symptomatic severe carotid stenosis. Clinical and experimental evidence demonstrates that both plaque morphology and biomechanical changes due to the device implantation can be possible causes of an unsuccessful treatment. In order to gain further insights of the endovascular intervention, a virtual environment based on structural finite element simulations was built to emulate the stenting procedure on generalized atherosclerotic carotid geometries which included a damage model to quantify the injury of the vessel. Five possible lesion scenarios were simulated by changing both material properties and vascular geometrical features to cover both presumed vulnerable and stable plaques. The results were analyzed with respect to lumen gain and wall stresses which are potentially related to the failure of the procedure according to previous studies. Our findings show that an elliptic lumen shape and a thinner fibrous cap with an underlying lipid pool result in higher stenosis reduction, while large calcifications and fibrotic tissue are more prone to recoil. The shielding effect of a thicker fibrous cap helps to reduce local compressive stresses in the soft plaque. The presence of a soft plaque reduces the damage in the healthy vascular structures. Contrarily, the presence of hard plaque promotes less damage volume in the fibrous cap and reduces stress peaks in this region, but they seem to increase stresses in the media-intima layer. Finally the reliability of the achieved results was put into clinical perspective.     

Carotid bifurcation position and branching angle in patients with atherosclerotic carotid disease

Carotid artery bifurcation (CB) is the preferred site for development of atherosclerosis (AS) in extracranial cerebral arteries; internal carotid artery stenosis is the most common cause of ischemic stroke. The frequent atherosclerotic disease of CB may best be explained by the hemodynamic influence of complex blood flow that results from the unique geometry of the bifurcation. Few papers analyze all possible geometric structural characteristics of this bifurcation. While performing many carotid endarterectomies, we noticed that a certain correlation between CB height in the neck and its angle existed, that a larger angle is accompanied with increased frequency of elongation and kinking and that CB shape influences distribution of atherosclerosis. The purpose of this paper is to quantify and evaluate these clinical observations. Radiogrametric analysis of 154 bi-plane orthogonal aortic arch arteriograms of patients with symptomatic atherosclerotic carotid artery disease was performed and a total of 289 CBs were analyzed. The CB height in relation to cervical spine segments was measured and real angles of each bifurcation were calculated. A positive linear correlation between CB height and angle exists: the CB angle increases /decreases 3.34 degrees for each third of the cervical vertebral body height or intervertebral space height. The CB is positioned a little higher on the left side. The proximal border of the atherosclerotic process is found at the level of intersection of the axes of the common carotid artery branches in 92.6% of examined CBs. In lower CBs (with smaller angles) the proximal border was located in the last segment of the common carotid artery, while in high bifurcations (wider angles) the proximal border of the AS process is more distally in the blood flow, in the beginning of the internal carotid artery, and the process was more extensive. High CBs are more suitable for eversion endarterectomy while normal and low CBs are more suitable for open (classic) carotid endarterectomy. The influence of the geometric risk factor demands further investigation.     

脑卒中患者血管危险因素与颈动脉粥样硬化的关系

目的研究脑卒中患者血管危险因素与颈动脉粥样硬化的关系。方法受试者151人主要为脑梗死及椎-基底动脉供血不足病例。将所有受试对象行颈动脉超声检查,采用二分类变量的Logistic回归分析方法对其危险因素进行筛选,找出与颈动脉粥样硬化改变相关的因素。结果年龄及吸烟与颈动脉内中膜增厚之间存在相关性,P=0.006（OR=1.08,95%CI 1.02-1.14）和0.01（OR=5.09,95%CI 1.47-17.61）;年龄、吸烟同样与颈动脉斑块之间存在相关性,P=0.006（ORn=n1.06,95%CI 1.06-1.11）和0.04（ORn=2.97,95%CI 1.04-8.50）,收缩压与颈动脉斑块呈正相关,P=0.04（OR=1.03,95%CI 1.00-1.05）,舒张压与颈动脉斑块呈负相关P=0.04（OR=0.96,95%CI 0.92-1.00）。结论随年龄的增大动脉内中膜增厚及颈动脉斑块的患病率增加,吸烟者内中膜增厚及颈动脉斑块比率高于不吸烟者;收缩压增加颈动脉斑块患病率增加,舒张压增加斑块患病率下降。     

More fibrosis and thrombotic complications but similar expression patterns of markers for coagulation and inflammation in symptomatic plaques from DM2 patients.

OBJECTIVE: One of the possible pathological mechanisms behind the increased vascular injury in diabetes mellitus type 2 (DM2) is the formation of advanced glycation end products (AGEs). The aim of this study was to investigate whether the presence of AGEs and specific markers for coagulation and inflammation in symptomatic atherosclerotic plaques from DM2 patients differs from plaques from nondiabetics. METHODS AND RESULTS: Carotid atherectomies were obtained from DM2 patients (n=11) and controls without DM2 matched for age and other cardiovascular risk factors (n=12) who were treated for symptomatic carotid artery stenosis. Plaques were graded according to the American Heart Association classification of lesions. More fibrosis and more thrombotic complications (p=0.007) were observed in carotid atherectomies from DM2 patients. Percentages of immunostained smooth muscle cells and macrophages in the lesions, quantified planimetrically, did not differ between the two groups. No differences were found in the immunostaining for T cells, tissue factor (TF), endothelial protein C receptor (EPCR), nuclear factor kappaB, and the AGE carboxymethyllysine. CONCLUSIONS: These findings demonstrate that DM2 is associated with increased plaque complications; however, a local changed presence of AGEs, TF, and EPCR seems not to be involved in this end stage of atherosclerosis.     

颈动脉粥样硬化及主动脉瓣钙化与动脉粥样硬化性肾动脉狭窄的关系

目的:探讨颈动脉粥样硬化、主动脉瓣膜钙化(aortic valve calcification,AVC)与动脉粥样硬化性肾动脉狭窄(atherosclerotic renal artery stenosis,ARAS)的关系。方法:对我院162例行选择性冠脉造影合并肾动脉造影的患者进行颈动脉超声和超声心动图检查,测量颈动脉内中膜厚度(carotid artery intima-media thickness,CIMT)和主动脉瓣钙化的情况,根据患者是否患有ARAS进行分组,比较两组的性别、年龄、吸烟、病史、血脂水平、CIMT、颈动脉粥样硬化发生率和AVC发生率,计算颈动脉粥样硬化和AVC对ARAS的预测价值。结果:ARAS组高血压病史患者的构成比、胆固醇水平、CIMT、颈动脉粥样硬化发生率、AVC发生率均显著高于对照组,有明显的统计学差异(P0.05)。颈动脉粥样硬化预测ARAS的灵敏度较高,特异度偏低;AVC的灵敏度低,而特异度高;二者联合特异度明显增高。结论:颈动脉粥样硬化、AVC对ARAS的诊断有一定的参考价值,可用于排除诊断。     

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。     

Three-dimensional spatial reconstruction of coronary arteries based on fusion of intravascular optical coherence tomography and coronary angiography

We present a three-dimensional (3D) spatial reconstruction of coronary arteries based on fusion of intravascular optical coherence tomography (IVOCT) and digital subtraction angiography (DSA). Centerline of vessel in DSA images is exacted by multi-scale filtering, adaptive segmentation, morphology thinning and Dijkstra's shortest path algorithm. We apply the cross-correction between lumen shapes of IVOCT and DSA images and match their stenosis positions to realize co-registration. By matching the location and tangent direction of the vessel centerline of DSA images and segmented lumen coordinates of IVOCT along pullback path, 3D spatial models of vessel lumen are reconstructed. Using 1121 distinct positions selected from eight vessels, the correlation coefficient between 3D IVOCT model and DSA image in measuring lumen radius is 0.94% and 97.7% of the positions fall within the limit of agreement by Bland–Altman analysis, which means that the 3D spatial reconstruction IVOCT models and DSA images have high matching level.     

Comparison between carotid stenting and carotid endarterectomy in early outcome

Carotid artery stenting (CAS) is a widely used method in prevention of stroke for carotid artery stenosis as an alternative to surgical treatment. Initial studies reveal higher morbidity and mortality rates for CAS than acceptable standards for carotid endarterectomy (CEA). The aim of this study was to compare results in a series of CAS with concurrent risk-matched group of CEA patients. The study included two groups of 50 patients with internal carotid artery stenosis. We compared early outcome (30 days after procedure) in risk-matched groups of patients that underwent these procedures. Post procedural complications were equally frequent in both groups. There was no significant difference in perioperative complication rates (P = 0.871). Comparison of these two methods shows that CAS and CEA are competitive methods for treatment of carotid artery stenosis. Particularly in symptomatic patients with high risk for surgery CAS is alternative treatment.     

颈动脉斑块LRNC特征可诊断2型糖尿病患者急性脑梗死的风险

2型糖尿病可能加重颈动脉斑块的易损性并增加缺血性中风的风险,关于2型糖尿病患者伴有颈动脉斑块特征的急性中风亚型鲜有研究报道。本研究旨在探讨2型糖尿病患者颈动脉斑块特征与MRI确定的急性脑梗死病变特征之间的关系。本研究以颈内动脉区急性脑血管病患者为研究对象,所有患者分为2型糖尿病组和非2型糖尿病组,分别行颈动脉和脑部MRI扫描,测定同侧颈动脉斑块的形态和特征,以及颅内和颅外颈动脉狭窄。基于中风亚型和急性脑梗塞病变模式对患者进行评估。研究结果表明,与非2型糖尿病患者相比,2型糖尿病患者颈动脉型IV-VI病变的患病率更高,斑块负荷更大,以及富脂质坏死核(LRNC)更大。在有症状的颈动脉LRNC患者中,与非2型糖尿病组相比,2型糖尿病组颈内动脉区出现较多的伴有大穿孔动脉梗塞形态和较大的急性脑梗塞。LRNC%>23.5%的颈动脉斑块是2型糖尿病患者存在颈动脉狭窄的急性脑梗塞病变的独立危险因素。颈动脉斑块特征的量化,尤其是MRI诊断的富脂质坏死核对中风风险具有潜在应用价值。     

Hcy, hs-CRP与急性脑梗死患者颈动脉粥样硬化关系的研究

目的:探讨急性脑梗死患者血清同型半胱氨酸(Hcy)、超敏C反应蛋白(hs-CRP)与颈动脉粥样硬化的相关性及临床意义。方法:收集确诊为急性脑梗死患者90例,对患者进行颈动脉超声检查,根据颈动脉狭窄程度将患者分成颈动脉内膜正常组、轻度狭窄组、中-重度狭窄组。比较三组患者斑块检出率、Hcy、hs-CRP水平和IMT厚度,同时对Hcy、hs-CRP与IMT进行相关性分析。结果:中-重度狭窄组斑块检出率为86.4%,显著高于轻度狭窄组和颈动脉内膜正常组(P0.05);颈动脉内膜正常组Hcy、hs-CRP水平以及IMT厚度均显著低于颈动脉轻度狭窄组、中-重度狭窄组(P0.05);hs-CRP与IMT呈正相关(r=0.71,P0.05);Hcy与IMT呈正相关(r=0.79,P0.05)。结论:血清Hcy和hs-CRP水平与颈动脉粥样硬化程度密切相关,Hcy、hs-CRP联合检测对急性脑梗死的早期诊断和预后有着重要临床意义。     

Circulating oxidized low-density lipoprotein and common carotid artery intima-media thickness in a random sample of middle-aged men

Circulating oxidized low-density lipoprotein (oxLDL) has been suggested to play an important role in atherosclerosis development. According to previous observations, oxLDL correlates with clinically manifest coronary and carotid artery disease. We investigated the association between the oxLDL concentration measured directly in plasma and common carotid artery intima-media thickness (IMT) in a population-based, case-control study in middle-aged men from Southern Finland. oxLDL was determined in 214 men by a commercially available sandwich ELISA test (Mercodia). Carotid artery IMT was measured at 12 standardized segments by B-mode ultrasonography (at the near and far wall of the left and right common carotid arteries, bifurcations and internal carotid arteries), and the overall mean maximum IMT (MMaxIMT) was calculated. The MMaxIMT of the carotid arteries was significantly associated with circulating oxLDL (r_s=0.16, p=0.018). In a stepwise multiple regression model with MMaxIMT as dependent variable and systolic blood pressure, smoking, oxLDL, HDL cholesterol and apolipoprotein B as covariates, systolic blood pressure (=0.22, p<0.001), oxLDL (=0.15, p=0.022) and smoking (=0.17, p=0.014) showed an independent association with IMT (R²=0.10, p<0.001). Our results show that oxLDL measured directly from plasma is independently associated with subclinical carotid artery atherosclerosis in middle-aged men.     

Perioperative and early postoperative neurological deficit in older patients during carotid artery thrombendarterectomy

Cerebrovascular accidents, strokes in particular, are among the most frequent causes of death today in developed countries. In the last two decades, stroke was the second most frequent cause of death in Primorsko-Goranska Region in Croatia. In older patients, individuals older than 65 years of age have an increased risk of stroke, mainly because the degree of carotid artery stenosis increases with age. The most frequent complication of the high percent stenosis of the carotid arteries is thrombosis in the area of atherosclerotic changes of blood vessels. With the increase in the age of the population, there is also an increase in the number of risk factors of cerebrovascular accident. Doppler ultrasound sonography and Multi Slice CT scans have the most prominent role in the early detection of atherosclerotic changes and in the assessment of the degree of carotid artery narrowing. Today, in Croatia as well as worldwide, thrombendarterectomy holds the most important place in stroke prevention. Between 2006 and 2009, 209 patients underwent surgical intervention at the Clinical Hospital Center in Rijeka for high degree of carotid artery narrowing. In the group younger than 65 years of age, which consisted of 53 patients, a neurological deficit was noted in 4 patients (7.54%) in the perioperative and early postoperative course. In the group of individuals older than 65 years of age, which consisted of 156 patients, a neurological deficit was noted in 9 patients (5.76%). There was no significant statistical difference in the incidence of neurological deficit, nor in the mortality in individuals older than 65 years of age during carotid arteries thrombendarterectomy.     

兔颈动、静脉移植桥血管狭窄模型的建立及其电镜观察

目的：建立兔颈动、静脉移植血管桥动物模型,观察移植桥血管内膜增生和狭窄的电镜下表现。方法：通过兔双侧颈动脉进行动脉桥和静脉桥的移植,形成双侧移植血管桥再狭窄动物模型。在第8周施行血管桥移植手术的同时留取右侧颈动静脉标本作为对照血管,再分别于第12周、16周和第20周分别处死模型兔,采集移植桥血管标本,在光镜下测量其内膜厚度、面积、狭窄度,并进行电镜观察。结果：颈动脉和颈静脉桥移植后,随着时间的延长,桥血管的出现平滑肌迁移,脂质沉积,内膜增生,血管狭窄等改变,且以静脉桥血管的病理改变更为明显。结论：在兔形成动脉粥样硬化病变基础上,进行双侧颈动脉血管桥的移植,建立兔双侧颈动脉移植血管桥再狭窄动物模型,有利于设立自身对照,研究术后动静脉桥再狭窄差异机制;建立动、静脉桥后,位于血管中膜的平滑肌细胞出现向血管内膜迁移现象,说明中膜平滑肌细胞迁移进入内膜导致新内膜形成是血管再狭窄的重要环节。     

颈动脉狭窄的显微外科治疗

目的:评价颈动脉内膜剥脱术治疗颅外颈动脉狭窄的疗效,以及经颅多普勒超声(TCD)、微血管多普勒超声(MVD)应用的价值。方法:回顾性分析2012年5月至2013年5月采用颈动脉内膜剥脱术治疗的19例颅外颈动脉狭窄的资料。均伴有不同程度的脑缺血症状。颈动脉狭窄程度2例中度狭窄,17例重度狭窄。同时行颈动脉内膜剥脱术均在显微镜下操作。1例采用补片成形。18例术中采用TCD及MVD监测下完成,1例未采用超声监测。结果:手术成功率为100%,无死亡率。术前脑缺血症状术后患者均有不同程度的恢复。均未发现过度灌注的并发症。结论:颈动脉内膜剥脱术治疗颅外颈动脉狭窄是一种安全、有效的措施;MVD及TCD监测对于显微手术有着重要意义。