Coronary angiography by computed tomography: coronary imaging evolves

Rapid technological advances have facilitated high-resolution noninvasive coronary angiography using multislice computed tomography. Appropriateness guidelines recently have been published in the Journal of the American College of Cardiology and endorsed by several imaging specialty societies. Clinical studies are now available supporting the use of this method in selected diagnostic situations, particularly when the exclusion of coronary artery disease is of paramount clinical concern.     

The incidence of coronary anomalies on routine coronary computed tomography scans

The incidence of coronary anomalies (CCAs) in a typical angiographic study was 1.3%.1 Studies have been conducted on CCAs using conventional invasive coronary angiography in highly selected groups of patients but these studies may not reflect the true incidence of CCAs.Although the majority of CCAs are benign and incidentally detected during conventional angiography, certain CCAs may cause syncope, heart failure or sudden death, especially among young athletes.2,3 The US National Registry of Sudden Death in Athletes at the Minneapolis Heart Institute Registry found that CCAs were the second most common cause of sudden cardiac death (out of 17% of the population who died of cardiac-related causes).4Although conventional invasive coronary angiography is considered the gold standard for the diagnosis of CCAs, transthoracic two-dimensional echocardiography, transoesophageal echocardiography, magnetic resonance imaging and multi-slice computed tomography (MSCT) can all identify for diagnosis, CCAs in certain groups of patients.5-10 Transthoracic twodimensional echocardiography may depict the origin of the coronary arteries, especially the left main artery, but successful detection of coronary anomalies depends on the age and size of the patient.5,6Transoesophageal echocardiography has an increased success rate of identifying coronary anomalies in comparison with two-dimensional echocardiography. Nevertheless, the position of the transducer, cardiac motion, and the curvilinear course of the vessel all affect visualisation of coronary anomalies. Moreover, transoesophageal echocardiography is a semi-invasive method and is time consuming.6,7Magnetic resonance (MR) imaging provides an accurate assessment of the course of anomalous coronary arteries.8,9 However, this technique cannot be performed in patients with pacemakers, certain types of arrhythmias or defibrillating devices, and it may be difficult to perform in claustrophobic patients. Furthermore, the spatial resolution of MR imaging is substantially inferior to that of the newest generation of CT scanners.10Myocardial bridging (MB) is defined as the compression of a coronary artery during systole while it is normal in diastole. MB has been linked to serious cardiac events.11 The incidence of myocardial bridging in the population varies substantially according to invasive coronary angiography (13%) and autopsy (15–85%).12,13 The reported incidence of MB has increased up to 44% when using 64-MSCT.14 Because of its ability to cause serious cardiac events, diagnosing MB is clinically important.MSCT is a minimally invasive method that provides excellent temporal and spatial resolution of the coronary arteries. There have been a limited number of studies evaluating CCAs and MB with 64-MSCT. The aim of this study was to assess the incidence of CCAs and MB using 64-MSCT in a relatively large population.     

冠状动脉CT造影评估冠状动脉钙化进展及临床意义

冠状动脉粥样硬化是冠心病的病理学基础,而冠状动脉钙化是粥样硬化病变的重要标志。检测和评估冠状动脉钙化不仅对预测心血管事件有重要意义,还有助于了解疾病进展,从而更好地指导临床诊治。冠状动脉CT造影(CCTA)是对冠状动脉钙化斑块进行精确量化评估的无创检查手段,其对于定量冠状动脉钙化以及预后评估具有重要的临床价值。本文对冠状动脉钙化CCTA检测方法及其临床应用等进行综述。     

64层CT冠状动脉成像技术和冠状动脉造影对冠状动脉疾病诊断的对照研究

目的比较64层计算机断层摄影扫描冠状动脉成像技术(64-slice computed tomography coronaryangiography,64-SCTCA)和冠状动脉造影(coronary artery angiography,CAG)在冠状动脉粥样硬化性心脏病(冠心病)诊断中的价值。方法回顾性分析126例疑似冠心病的患者64-SCTCA和CAG检查资料,并对两组资料进行对比分析。结果 64-SCTCA和CAG检查结果中可用于评价的病变血管段支数比较,差异无统计学意义(P0.05)。CAG共发现≥50%狭窄节段242个,64-SCTCA共发现≥50%狭窄节段199个,两种检查方法对病变狭窄的显示情况比较,差异无统计学意义(P0.05)。全部126例冠心病患者中有91%通过64-SCTCA发现(110/121)。64-SCTCA诊断冠状动脉病变血管的敏感性、特异性、阳性预测值、阴性预测值分别为81.6%、98.8%、79.5%、99%。结论 64-SCTCA可作为冠心病无创、便捷、可靠的检查方法。     

Non-invasive multislice computed tomography coronary angiography for imaging coronary arteries, stents and bypass grafts

Abstract Multislice computed tomography (MSCT) is evolving rapidly and available data suggest that MSCT coronary angiography may be a reliable and accurate non-invasive imaging modality of coronary arteries. Current generations of MSCT scanners have high sensitivity and specificity for diagnosing native coronary artery disease and coronary bypass graft occlusion. The performance of MSCT in the evaluation of stent patency is still being assessed. In comparison with conventional selective coronary angiography (SCA), MSCT is non-invasive, cheaper and it has the advantages of imaging plaque compositions as well as assessment of luminal patency. Nevertheless, the role of MSCT in the management of coronary artery disease is yet to be fully defined.     

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.     

Cardiovascular computed tomographic angiography evaluation following unsuccessful invasive angiography: The clinical utility of 3D volume rendering

In an appropriate clinical setting, cardiac CT angiography (CCT) can be used as a safe and effective noninvasive imaging modality for defining coronary arterial anatomy by providing detailed three‐dimensional anatomic information that may be difficult to obtain with invasive coronary angiography (ICA). We present a patient where coronary angiography by ICA was unsuccessful and where the subsequent CCT proved to be very useful in providing us relevant information. © 2009 Wiley‐Liss, Inc.     

冠状动脉多层螺旋CT成像及冠脉造影对冠脉搭桥术后桥血管的评价

目的观察冠状动脉多层螺旋CT成像及冠脉造影对冠脉搭桥手术后桥血管的评价作用。方法33例冠脉搭桥手术患者,术前常规冠脉造影检查,手术行不停跳冠脉搭桥术,手术后1 a行冠状动脉多层螺旋CT成像,并于冠状动脉多层螺旋CT成像复查后1周内行冠脉造影检查。结果33例患者共行冠脉搭桥101支,冠状动脉多层螺旋CT成像能够成功显示99支,显示率为98.02%。冠状动脉多层螺旋CT成像与冠脉造影结果对比,其对冠脉搭桥手术后桥血管狭窄和阻塞评价敏感度达100%。结论应用冠状动脉多层螺旋CT成像对冠脉搭桥术后桥血管评价简便、无创,具有较好的可信性和可行性。     

Spiral multislice computed tomography coronary angiography: a current status report

Multislice computed tomography coronary angiography (MSCT-CA) has emerged as a powerful noninvasive diagnostic modality to visualize the coronary arteries and to detect significant coronary stenoses. The latest generation 64-slice computed tomography (CT) scanners is a robust technique which allows high-resolution, isotropic, nearly motion-free coronary imaging. Coronary stenoses are detected with high sensitivity and a normal scan accurately rules out the presence of a coronary stenosis. With the introduction of further novel concepts in CT-technology one may expect that MSCT-CA will become a clinically used diagnostic tool.     

Association between smoking habits and severity of coronary stenosis as assessed by coronary computed tomography angiography

Smoking promotes arteriosclerosis and is one of the most important coronary risk factors. However, few studies have investigated the association between smoking habits and the severity of coronary stenosis as assessed by coronary computed tomography angiography (CTA). We enrolled 416 patients [165/251 = smoker (past and current)/non-smoker)]. They had all undergone CTA and either were clinically suspected of having coronary artery disease (CAD) or had at least one cardiovascular risk factor. We divided the patients into smoking and non-smoking groups, and evaluated the presence of CAD, the number of significantly stenosed coronary vessels (VD), and the Gensini score as assessed by CTA in the two groups. The incidence of CAD, VD, the Gensini score, and coronary calcification score in the smoking group were all significantly greater than those in the non-smoking group (CAD, p = 0.009; VD, p = 0.003; Gensini score, p = 0.007; coronary calcification score, p = 0.01). Pack-year was significantly associated with VD and the Gensini score, and was strongly associated with multi-vessel disease (2- and 3-VD) (p < 0.05), whereas the duration of cessation in past smokers was not associated with VD or the Gensini score. Pack-year, but not the duration of cessation, may be the most important factor that was associated with the severity of coronary stenosis in terms of VD and the Gensini score.     

Multislice computed tomography angiography in the diagnosis of coronary artery disease

Multislice CT angiography represents one of the most exciting technological revolutions in cardiac imaging and it has been increasingly used in the diagnosis of coronary artery disease. Rapid improvements in multislice CT scanners over the last decade have allowed this technique to become a potentially effective alternative to invasive coronary angiography in patients with suspected coronary artery disease. High diagnostic value has been achieved with multislice CT angiography with use of 64- and more slice CT scanners. In addition, multislice CT angiography shows accurate detection and analysis of coronary calcium, characterization of coronary plaques, as well as prediction of the disease progression and major cardiac events. Thus, patients can benefit from multislice CT angiography that provides a rapid and accurate diagnosis while avoiding unnecessary invasive coronary angiography procedures. The aim of this article is present an overview of the clinical applications of multislice CT angiography in coronary artery disease with a focus on the diagnostic accuracy of coronary artery disease; prognostic value of coronary artery disease with regard to the prediction of major cardiac events; detection and quantification of coronary calcium and characterization of coronary plaques. Limitations of multislice CT angiography in coronary artery disease are also briefly discussed, and future directions are highlighted.     

冠状动脉计算机断层扫描血管造影双低扫描对冠状动脉狭窄的诊断性能

目的观察分析冠状动脉(冠脉)计算机断层扫描血管造影(CTA)双低扫描对冠脉狭窄的诊断性能。方法选取2017年7月至2018年7月于宝鸡市妇幼保健院经心电图诊断疑似冠脉狭窄的患者94例,分别进行计算机断层扫描血管造影双低扫描检查和数字减影血管造影(DSA)检查,将接受计算机断层扫描血管造影检查的患者纳入观察组(n=114),数字减影血管造影检查的为对照组(n=108)。记录两组患者的诊断结果,分析两组检查方法的灵敏度、特异度、准确度,以及对冠脉狭窄程度的检测结果。结果计算机断层扫描血管造影双低扫描检查的灵敏度为96.67%,特异度为80.00%,准确度95.74%。在对狭窄程度诊断结果的比较中,计算机断层扫描血管造影双低扫描与DSA的诊断结果比较,差异无统计学意义(P>0.05)。结论冠脉计算机断层扫描血管造影双低扫描能够清晰显示冠脉狭窄的部位、程度,准确性较好,且对患者辐射量小,可以应用于对冠脉狭窄的诊断。