基层医院多层螺旋CT冠状动脉检查现状分析

目的评估基层医院多层螺旋CT(MSCT)行冠状动脉检查的准确性。方法收集在基层医院已行MSCT检查,提示冠状动脉狭窄患者90例,再经北京阜外心血管病医院行冠状动脉造影确诊,采用Kappa检验比较2种检查方法结果的一致性。结果 MSCT诊断冠心病的准确率为88.9%。诊断冠状动脉狭窄程度的准确率39.0%,诊断左前降支、左回旋支和右冠状动脉的准确率分别为45.5%、37.5%和33.3%。在诊断心肌肌桥两者无一相符,诊断钙化准确率较高为80.0%。MSCT检查冠状动脉各节段的狭窄与冠状动脉造影一致性差。左主干、左前降支、左回旋支和右冠状动脉的Kappa值均0.75。结论基层医院MSCT诊断冠心病的准确率较高,但在诊断血管狭窄程度上准确率较低。     

糖尿病患者CT冠状动脉造影的诊断价值

目的通过对比观察糖尿病与非糖尿病患者CT冠状动脉造影（CTCA）的特征,探讨CTCA在糖尿病合并冠心病患者中的诊断价值。方法对380例糖尿病患者及481例非糖尿病患者进行CTCA检查,其中111例患者（糖尿病41例,非糖尿病70例）行选择性冠状动脉造影检查,观察CTCA与选择性冠状动脉造影的相关性,并比较糖尿病与非糖尿病患者冠状动脉病变的特征。结果糖尿病与非糖尿病患者中CTCA检查与选择性冠状动脉造影均相关良好,糖尿病患者血管狭窄发病率较非糖尿病患者显著增高（45．8％ vs 24．5％;P〈0．05）,多支病变发病率明显增高（P〈0．05）。结论糖尿病患者冠状动脉病变特征复杂,CTCA在糖尿病患者冠心病的筛查中具有重要意义。     

Myocardial Ischemia Evaluation With Dual-source Computed Tomography: Comparison With Magnetic Resonance Imaging

Introduction and objectives

Computed tomography does not accurately determine which coronary lesions lead to myocardial ischemia and consequently further tests are required to evaluate ischemia induction. The aim of this study was to compare diagnostic accuracy between dual-energy computed tomography and magnetic resonance imaging in the assessment of myocardial perfusion and viability in patients suspected of coronary artery disease.

Methods

A prospective study was performed in 56 consecutive patients (39 men [69.6%]; mean age [standard deviation], 63 [10]; range, 23-81). Computed tomography was performed with the following protocol: 1, adenosine stress perfusion; 2, coronary angiography; and 3, delayed enhancement. Magnetic resonance imaging for the evaluation of stress perfusion and delayed enhancement was performed within 30 days. Two observers in consensus analyzed the perfusion and delayed enhancement images.

Results

We studied 952 myocardial segments and 168 vascular territories. In a per-segment analysis, the sensitivity, specificity, and positive and negative predictive values of computed tomography compared with magnetic resonance were 76%, 99%, 89%, and 98% for perfusion defects, and 64%, 99%, 82%, and 99% for delayed enhancement, respectively. In a per-vascular territory analysis, the same measures were 78%, 97%, 86%, and 95% for perfusion defects, and 72%, 99%, 93%, and 97% for delayed enhancement, respectively. The mean radiation dose was 8.2 (2) mSv.

Conclusions

Dual-source computed tomography may allow accurate and concomitant evaluation of perfusion defects and myocardial viability and analysis of coronary anatomy.     

双源CT双能量冠状动脉斑块成像的初步应用

目的探讨双源CT双能量成像技术进行冠状动脉斑块成像的可行性。方法 40例病人行双能量CT冠状动脉斑块成像。结果 40例受检者均能得到冠状动脉成像的单能数据及双能量数据,其中10例行DSA者,CTA与DSA所见一致。其中3例行IVUS检查,共5处斑块,其中4处斑块双能图像与IVUS所见一致。结论单次对比增强双能量CT心脏成像,可同时获得优良的冠状动脉和冠状动脉斑块成像,并降低了射线剂量。     

多排螺旋计算机体层扫描对冠状动脉钙化检测的国外研究进展

冠状动脉钙化是冠状动脉粥样硬化病变存在的标志,反映了粥样硬化斑块,特别是钙化斑块的存在和分布。在过去10余年里.大量电子束计算机体层扫描研究围绕冠状动脉钙化的临床价值、检测方法和可重复性以及冠状动脉钙化演变等热点问题展开。随着多排螺旋计算机体层扫描的不断发展和普及,它在冠状动脉钙化检测方面的价值也在成为热点,现就对多排螺旋计算机体层扫描在这些方面应用的国外研究现状做一综述。     

Should computed tomography coronary angiography be aborted when the calcium score exceeds a certain threshold in patients with chest pain?

Background

There is ongoing debate about whether a computed tomography coronary angiography (CTCA) should be aborted when the calcium score (CS) exceeds a certain threshold in patients with chest pain. The aim of this study was to discover whether specific “cutpoints” regarding coronary artery CS could be determined to predict severe coronary stenoses assessed by CTCA, thus identifying patients amenable to an invasive diagnostic approach.

Methods

294 consecutive patients with chest pain of uncertain cause who were referred for non-invasive diagnostic CTCA were included. Subjects underwent Agatston CS and CTCA using current 64-slice technology.

Results

Severe coronary stenoses were noted in 75 of 294 (25.1%) patients on CTCA. A very high prevalence of severe coronary stenoses was found in patients with CS ≥ 400 (87.0%). The CS had area under the ROC curve 0.86 to predict severe coronary stenoses on CTCA. The best discriminant cut-off point was CS ≥ 400 (sensitivity of 55.3%, specificity of 93.5, positive predictive value of 85.8%, negative predictive value of 84.0%). Multivariable logistic regression analysis controlling for traditional risk factors showed CS ≥ 400 remained an independent predictor of severe coronary stenoses on CTCA (OR 14.553, 95% confidence interval 4.043 to 52.384, p < 0.001).

Conclusions

CS can be used as a “gatekeeper” to CTCA in patients with chest pain. Due to the very high prevalence of severe coronary stenoses in patients with CS ≥ 400, further evaluation with CTCA is not warranted as these patients should be referred to invasive coronary angiography, avoiding the repeated exposure to ionizing radiation and iodinated contrast.     

64层螺旋CT血管成像与冠状动脉造影对冠心病诊断价值的对比研究

目的评价64层螺旋CT在冠状动脉造影方面的诊断价值。方法58例临床诊断或可疑冠心病患者行64层螺旋CT冠状动脉成像检查,分别对左主干、左前降支、回旋支和右冠状动脉及其分支的重建图像行影像学评价,所有患者均行常规选择性冠状动脉造影检查作为对照。结果58例患者共757(87.0%)节段的冠状动脉(血管直径≥1.5 mm)成像,638节段(84.3%)可用于多层螺旋CT和冠状动脉造影定量分析。冠状动脉造影共发现狭窄101节段,多层螺旋CT发现狭窄104节段,多层螺旋CT对冠状动脉狭窄诊断的敏感性为86.1%,特异性为96.8%。结论64层螺旋CT冠状动脉造影可作为诊断冠状动脉病变的一种无创筛选方法。     

Important Advances in Technology and Unique Applications to Cardiovascular Computed Tomography

For the past decade, multidetector cardiac computed tomography and its main application, coronary computed tomography angiography, have been established as a noninvasive technique for anatomical assessment of coronary arteries. This new era of coronary artery evaluation by coronary computed tomography angiography has arisen from the rapid advancement in computed tomography technology, which has led to massive diagnostic and prognostic clinical studies in various patient populations. This article gives a brief overview of current multidetector cardiac computed tomography systems, developing cardiac computed tomography technologies in both hardware and software fields, innovative radiation exposure reduction measures, multidetector cardiac computed tomography functional studies, and their newer clinical applications beyond coronary computed tomography angiography.     

Anomalous coronary arteries in adults detected by multislice computed tomography: presentation of cases from multicenter registry and review of the literature

Anomalous coronary arteries are a rare condition, but they may cause myocardial ischemia, heart failure, and sudden death. We evaluated the prevalence and multislice computed tomographic (MSCT) findings of anomalous coronary arteries in a large number of patients from the multicenter registry. At four institutes, 29 (0.74%) out of 3910 patients were found to have anomalous coronary arteries by MSCT. They consisted of 15 patients with anomalous origins of the right coronary artery, 1 with right-sided origin of the left circumflex artery, 1 with right-sided origin of the left main coronary artery, 2 with double right coronary arteries, 2 with the absence of the left circumflex artery, 1 with absence of the right coronary artery, 6 with coronary artery fistulas, and 1 with Bland-White-Garland syndrome. Multislice computed tomography findings were consistent with those obtained by conventional coronary angiography in all 14 patients undergoing both diagnostic procedures. Multislice computed tomography permits three-dimensional comprehension of coronary arteries, which is suitable for the diagnosis of anomalous coronary arteries.     

Noninvasive coronary angiography by contrast-enhanced electron beam computed tomography

Electron beam computed tomography (EBCT) is a cross-sectional imaging method with high temporal and spatial resolution. So far, it has mainly been applied for the detection of coronary artery calcifications which permit the very sensitive detection of coronary atherosclerosis even in the very early stages. However, after intravenous injection of a contrast agent, EBCT also permits the direct visualization of the coronary artery lumen. For these investigations, a volume data set is acquired that consists of 40 axial cross-sections of the heart (3 mm slice thickness). To evaluate the coronary arteries as to the presence of stenoses and occlusions, various forms of postprocessing, including shaded surface display, maximum intensity projection, and multiplanar reconstruction, are applied. The sensitivities and specificities for the detection of coronary artery stenoses and occlusions are about 90%. Best results are obtained for coronary artery bypass grafts, the left main coronary artery, and the left anterior descending coronary artery, while reduced image quality impairs the results for the right coronary artery and the left circumflex coronary artery.     

2型糖尿病合并冠心病患者行双源CT冠状动脉造影的对比研究

目的探讨双源CT冠状动脉造影在2型糖尿病合并冠心病患者诊断中的应用价值。方法选择临床确诊或疑诊冠心病的2型糖尿病患者88例行CT冠状动脉造影检查,并同期行选择性冠状动脉造影。双源CT的原始数据均行容积再现、曲面重组、最大密度投影及横断面重建。结果 352支血管中(直径≥2 mm),双源CT冠状动脉造影显示≥50%狭窄的血管为163支,占46.3%;选择性冠状动脉造影显示≥50%狭窄的血管为155支,占44.0%。与选择性冠状动脉造影对照分析,双源CT冠状动脉造影评价冠状动脉狭窄(≥50%狭窄)的敏感性、特异性、阳性预测值以及阴性预测值分别为92.3%、89.9%、87.7%和93.7%。结论双源CT冠状动脉造影是检测2型糖尿病患者冠状动脉狭窄的可靠方法。     

老年人多层螺旋CT冠状动脉成像诊断冠状动脉狭窄的研究

目的评价64层螺旋CT冠状动脉成像在诊断老年患者冠状动脉狭窄中的临床应用价值。方法回顾性分析39例患者行64层螺旋CT冠状动脉造影的老年患者(>65岁)的影像资料,在15段分段法的基础上,评价每段冠状动脉CT造影的图像质量;以传统X线冠状动脉造影为“金标准”,评价CT血管造影诊断冠状动脉狭窄及其程度的价值。结果多层螺旋CT冠状动脉造影(MSCTA)评价冠状动脉狭窄的敏感度、特异度、阳性预测值和阴性预测值分别为98.9%(90/91)、98.2%(426/434)、91.8%(90/98)和99.8%(426/427)。冠状动脉MSCTA与传统X线冠状动脉造影(CAG)对血管狭窄程度评价具有很好的一致性。结论多层螺旋CT冠状动脉成像在诊断老年人冠心病中具有重要的临床应用价值。     

64层螺旋CT冠状动脉成像判定冠状动脉狭窄的价值

目的: 探讨64层螺旋CT冠状动脉成像（MSCTCA）判定冠状动脉狭窄的临床价值。方法: 回顾性研究在我科治疗并于2周内先后行MSCTCA和冠状动脉造影（CAG）的临床拟诊冠心病患者30(男21,女9)例;年龄49～74（62±7）岁,以CAG结果为准,计算评价指标。结果: 依节段计算的MSCTCA准确性,其灵敏度、特异度分别为50%、97%。若去除38个冠脉节段由于严重钙化而影响诊断的因素,则其灵敏度、特异度分别为74%、99%。结论: MSCTCA判断冠状动脉中、重度狭窄具有较高的准确性,对诊断冠心病尤其对筛选冠心病而言有较好的前景,但严重钙化病变影响冠状动脉狭窄程度的判断。     

64层螺旋CT对老年冠状动脉疾病患者的诊断价值评价

目的探讨64层螺旋CT对老年冠状动脉疾病患者的诊断价值。方法对61例疑为冠心病的老年患者进行冠状动脉64层螺旋CT扫描,并于1周之内进行冠状动脉造影检查。以冠状动脉造影为“金标准”,评价冠状动脉64层螺旋CT诊断老年冠状动脉疾病患者的敏感性、特异性、阳性预测值、阴性预测值及准确度。结果61例患者总计915个冠状动脉节段,64层螺旋CT能够评价其中882个节段(96．4％),其检测中度以上冠状动脉狭窄的敏感性75．6％,特异性88．1％,阳性预测值64．0％,阴性预测值92．8％,准确度85．4％。结论64层螺旋CT对老年冠状动脉疾病患者具有较高的诊断价值,有可能成为筛查老年人冠心病的一个较为可靠的无创检测手段     

Coronary CT angiography: Dose reduction strategies

With the introduction of 64- and post-64 slice computed tomography (CT) technology, coronary CT angiography has been increasingly used as a less invasive modality for the diagnosis of coronary artery disease. Despite its high diagnostic value and promising results compared to invasive coronary angiography, coronary CT angiography is associated with high radiation dose, leading to potential risk of radiation-induced cancer. A variety of dose-reduction strategies have been reported recently to reduce radiation dose with effective outcomes having been achieved. This article presents an overview of the various methods currently used for radiation dose reduction.     

Coronary Artery Calcium Scoring in Cardiovascular Risk Assessment

Identification of patients at risk of future coronary artery disease (CAD) events traditionally relies on scoring tools that take demographic and clinical characteristics into account (e.g., the Framingham risk score in the United States and the Heart Score in Europe). Although these scoring tools have been shown to have a good predictive value, they may still fail to recognize a proportion of patients with coronary atherosclerosis at risk for future CAD events. In order to improve risk stratification, direct visualization of subclinical atherosclerosis has been advocated. Electron‐beam computed tomography and multislice computed tomography provide a direct estimation of coronary calcium, a marker of coronary atherosclerosis. A large amount of data is available supporting the clinical value of the noninvasive assessment of coronary artery calcium score (CACS) with these techniques and its incremental prognostic information over traditional risk stratification. Aim of this review is to provide an overview of the literature regarding the prognostic value of CACS assessment. In addition, potential other applications of CACS assessment as well as the limitations of the technique are discussed.     

Anomalous coronary circulation: left anterior descending and left circumflex coronary arteries arising from the right sinus of valsalva

Approximately 1% of adults who undergo cardiac catheterization have coronary anomalies. Patients may present with chest pain, arrhythmias, presyncope, and sometimes sudden cardiac death. Multidetector computed tomography (MDCT) is an excellent tool for identifying coronary artery anomalies and defining their course and relationship to the great vessels and surrounding structures; its value is incremental to conventional angiography. We present a rare case of a coronary anomaly involving three separate ostia at the right sinus of Valsalva for the left and right coronary vessels.     

多层螺旋CT评价急性冠状动脉综合征及稳定性心绞痛患者斑块特征的作用

目的利用多层螺旋CT评价急性冠状动脉综合征(ACS)及稳定性心绞痛(SAP)患者冠状动脉病变的差异。方法连续性入选诊断为ACS及SAP、并于介入治疗前72h内行多层螺旋CT检查的患者45例,将诊断为ACS的31例作为ACS组,诊断为SAP的14例作为SAP组,将ACS组的病变分为罪犯病变和非罪犯病变,SAP组的病变定义为稳定病变;比较冠状动脉病变性质。结果 2组共有60处病变,ACS组40处,SAP组20处;ACS组罪犯病变非钙化斑块和脂质斑块比例明显高于同组非罪犯病变及SAP组的稳定病变(96.8%vs 55.6%vs 20.0%,83.3%vs 40.0%vs 25.0%,P<0.01);ACS组罪犯病变的血管截面积、斑块面积、重构指数、斑块的偏心指数明显高于同组的非罪犯病变及SAP组的稳定病变(P<0.05)。结论多层螺旋CT作为无创的影像学工具,可识别ACS与SAP患者冠状动脉斑块病变的差异。     

前瞻性心电触发轴位扫描技术在64层螺旋CT中的应用

目的探讨在64层螺旋CT冠状动脉成像中采用前瞻性心电触发轴位扫描技术的图像质量和辐射剂量。方法选择采用前瞻性心电触发轴位扫描技术进行64层螺旋CT冠状动脉成像的患者160例作为前瞻组。将相同扫描参数输入回顾性心电门控螺旋扫描程序,获得扫描剂量数据作为回顾组。由2名放射科医师分别进行图像重建和图像质量评价。冠状动脉图像质量分级采用4级评分法。结果 2名放射科医师在图像重建和图像质量评价方面均有良好的一致性。160例患者除8例图像有严重血管错层伪影、2例冠状动脉严重钙化,共显示1449个冠状动脉节段。1～3分以上的1431个节段(98.76%)具有较好的图像质量,可以满足临床诊断要求。前瞻组与回顾组的平均有效剂量差异有统计学意义[(3.17±1.17)mSv vs (22.09±6.72)mSv,P0.01]。结论在64层螺旋CT冠状动脉成像中采用前瞻性心电触发轴位扫描技术可在保证图像质量的同时显著降低辐射剂量。     

Different therapeutic proportion of patients undergone coronary angiography in the era of development in MSCT

Objective To study the different therapeutic proportion of the patient populations undergone coronary angiography (CAG) in the era of development in multislice spiral computed tomography(MSCT).Methods Two hundred and fifty four consecutive patients(mean age 59.24±10.65),who underwent CAG at Daxing Hospital from February 2007 through October 2007,were enrolled,160 patients were male and 94 were female.By evaluating from the coronary angiogram,the patients were not diagnosed to have coronary heart disease(CHD) with less than 50% diameter stenosis of coronary artery;the patients to have CHD with more than or equal to 50% stenosis of coronary artery;the patients were performed the procedure of percutaneous coronary intervention(PCI) with more than or equal to 70% stenosis;the patients were proposed to have coronary aortic bypass graft(CABG) surgery with left main coronary artery lesions or diffuse triple coronary artery lesions.Results In the 254 consecutive patients,59 patients(23.2%) had not been diagnosed to have CHD;195(76.8%)to have CHD,of these patients with CHD,49 patients(19.3%)were not indicated for PCI (including the patients receiving follow-up coronary angiography after stenting),81(31.9%)had been performed the procedure of stent implantation,57(22.4%)proposed to have CABG,8(3.1%)the procedure of PCI had not been successful,or had not been performed because of patients opposing to this therapy.Conclusion Multislice spiral computed tomography can be applied as a non-invasive screening tool to exclude the presence of CHD,to increase the positive proportion of the populations with CHD in all patients receiving coronary angiograhpy,to avoid the use of CAG in a subset of patients.