苏格兰心脏CT研究的进展和展望

苏格兰心脏CT研究（SCOT-HEART）是一项开放标签、多中心、随机对照试验,旨在评估冠状动脉CT血管成像（CCTA）是否影响胸痛病人的诊断、治疗及预后。这是首次在对常规临床诊疗过程分析中加入CCTA对病人结局影响的实验,并证实了CCTA在冠心病诊断、诊疗决策优化以及改善病人预后等方面的价值。此外,还提示高危斑块特征与病人预后的关系以及联合功能和解剖学检查对疑似冠心病心绞痛病人的增量价值等。主要介绍SCOT-HEART研究的背景、目的、设计、对心血管医学的贡献以及未来的发展方向。     

CT-SYNTAX评分在复杂冠状动脉疾病心肌血运重建决策中的应用进展

复杂冠状动脉疾病（CAD）心肌血运重建治疗策略的选择是临床医师关注的问题,基于有创冠状动脉造影（ICA）的SYNTAX评分是当前重要的临床指导依据。随着冠状动脉CT血管成像（CCTA）的普及,基于CCTA的SYNTAX评分（CT-SYNTAX）成为研究热点。基于CCTA的血流储备分数（FFR_CT）可提供CAD的功能学信息,实现了CT-SYNTAX评分从解剖学向功能学的提升。就CT-SYNTAX评分在复杂CAD病人治疗策略中应用的研究进展予以综述。     

CCTA技术对冠状动脉狭窄及其钙化斑块的评估

冠状动脉CT血管成像（CCTA）是一种可无创检测冠状动脉粥样硬化性疾病的成像手段,已成为临床筛查及诊断冠心病的首要检查方法。但对于钙化严重的冠状动脉节段,CCTA的特异性及阳性预测值偏低,可导致病人过度治疗,因此限制了CCTA的临床应用。综述钙化斑块伪影对CCTA的影响,并就CCTA对冠状动脉狭窄准确评估的相关技术进展进行分析,以利于临床诊断中提高CCTA对冠状动脉狭窄率的评估。     

冠状动脉CT成像钙化斑块减影技术的临床应用

冠状动脉CT血管成像(CCTA)作为一种无创的冠状动脉成像方法,已经成为临床诊断冠心病的首选影像检查方法.由于钙化斑块往往会干扰CCTA对冠状动脉狭窄严重程度的评估,现临床上开发出一种新的冠状动脉成像技术方法——冠状动脉CT成像钙化斑块减影技术.通过去除钙化斑块对冠状动脉成像的干扰,从而对冠状动脉血管作出有效的评估.本文就这种新的影像技术方法的进展、原理及其在临床中的应用进行综述.     

FFR CT诊断冠心病的初步应用体会

目的初步探究基于CT血管成像的无创血流储备分数（FFR_CT）与传统有创血流储备分数（FFR）相比在冠心病病人心肌缺血诊断方面的应用价值。方法纳入2017年2月-12月于我院接受冠状动脉CT血管成像（CCTA）检查且后续1周内完成冠状动脉造影（ICA）及FFR检查的可疑或确诊冠心病的病人20例,其中男13例,女7例,平均年龄（64.72±8.01）岁。对病人CCTA影像采用简化一维cFFR软件进行FFR_CT值测定,以有创性FFR结果作为金标准,分析比较FFR_CT对冠心病病人心肌缺血诊断的敏感度、特异度、阳性预测值、阴性预测值、准确度。绘制受试者操作特征（ROC）曲线,比较FFR_CT与CCTA的诊断准确性。采用Pearson相关性检验及Bland-Altman方法比较FFR_CT与FFR的诊断相关性及一致性。结果以病变为分析单位,FFR_CT与CCTA诊断敏感度、特异度、阳性预测值、阴性预测值、准确度分别为93.5%、86.2%、87.9%、92.6%、90.0%及83.9%、79.3%、82.1%、81.2%、81.7%。FFR_CT和CCTA的ROC曲线下面积分别为0.960及0.892。FFR_CT与FFR诊断一致性及相关性良好（r=0.973,P<0.001）。结论FFR_CT对于冠心病病人心肌缺血诊断具有良好的临床应用价值。     

冠状动脉CTA管腔内衰减梯度的应用进展

冠状动脉CTA(coronary CTA, CCTA)已成为冠状动脉疾病无创筛查的首选检查方法。然而CCTA只能提供冠状动脉解剖学信息,无法提供血流动力学的改变。随着CCTA新技术的发展,CCTA管腔内衰减梯度(transluminal attenuation gradient, TAG)可以提供更多的功能学信息。本文对TAG在冠状动脉疾病中的应用进行综述。     

基于CCTA的冠状动脉周围脂肪组织影像组学特征预测急性冠状动脉综合征

目的 评估基于冠状动脉CT血管成像（CCTA）的冠状动脉周围脂肪组织（PCAT）影像组学特征对疑似冠心病病人2年内发生急性冠状动脉综合征（ACS）的预测能力。方法 回顾性收集接受CCTA检查的疑似冠心病病人,将CCTA检查后2年内发生ACS的病人作为ACS组（81例）,2年内未发生ACS的疑似冠心病病人作为对照组（81例）。ACS组年龄44~85岁,平均（64.01±10.09）岁,男57例;对照组年龄39~89岁,平均（62.91±10.11）岁,男56例。将2组病人随机以 3∶1 的比例分为训练集（ACS组60例,对照组60例）和验证集（ACS组21例,对照组21例）。筛选基于CCTA的PCAT影像组学特征,采用多因素Logistic回归分析构建PCAT影像组学评分模型,并基于PCAT影像组学特征中的CT密度值建立PCAT密度模型。采用DeLong检验比较不同数据集中2个模型的诊断效能差异。采用受试者操作特征（ROC）曲线、校准曲线及决策曲线比较2种模型的预测效能。结果 训练集和验证集中,ACS组和对照组病人的临床资料间差异均无统计学意义（均P>0.05）。从基于CCTA影像所示的冠状动脉斑块周围PCAT共提取107个影像组学特征,最终筛选出21个最优影像组学特征,包括形态学特征5个、直方图特征1个、纹理特征15个,采用Logistic回归分析构建PCAT影像组学评分模型。基于提取的PCAT组学特征中平均 CT密度值构建PCAT密度模型。2种模型预测2年内发生ACS事件的诊断效能分析显示,PCAT 影像组学评分模型在训练集及验证集中的曲线下面积（AUC）（AUC=0.841,0.839） 均高于PCAT 密度的AUC（AUC=0.603,0.588）。训练集中,PCAT影像组学评分的诊断效能优于PCAT密度模型（P<0.05）,并在验证集中得到验证（P<0.05）。PCAT影像组学评分对发生ACS事件的预测结果与实际结果一致性高于PCAT密度。PCAT影像组学评分的临床应用价值显著优于PCAT 密度。结论 基于CCTA 的PCAT影像组学特征可为ACS事件的发生提供更多的预测信息。PCAT 影像组学评分对2年内发生ACS事件的预测能力显著优于PCAT 密度。     

CT-FFR对冠状动脉狭窄功能评价的临床价值

CT冠状动脉血流储备分数(CT-FFR)可无创性检查冠状动脉粥样硬化性心脏病(冠心病),是一种结合了解剖与功能的检查方法。CT-FFR是基于冠状动脉CT血管成像(CCTA)的影像数据测得的,具有CCTA和冠状动脉血流储备分数(FFR)的优势。CT-FFR从解剖学方面评估病变的狭窄程度,同时可以从血流动力学方面测定狭窄冠状动脉是否存在缺血及缺血的严重程度。综述总结了CT-FFR的优势、诊段效能及其临床应用。     

使用第3代双源CT和自动选择管电压技术进行冠状动脉CTA检查的诊断准确性:基于正常体质量及肥胖病人群体的临床应用

<正>摘要目的研究使用第3代双源CT(DSCT)对正常体质量及肥胖病人行冠状动脉CT血管成像(CCTA)检查的诊断准确性。方法回顾性分析了76例接受过CCTA和有创性冠状动脉血管造影的病人。在CCTA检查中,使用前瞻性心电门控以及自动管电压选择技术(ATVS)。基于体质量指数,病人被分为2组:组A(30 kg/m~2,37例)和组B(≥30 kg/m~2,39     

用好冠状动脉CT成像这把“双刃剑”

近年来,冠状动脉CT血管成像(coronary CT angiography,CCTA)技术日臻成熟,高性能的成像设备使得冠状动脉清晰成像成为可能,CCTA正在成为无创诊断冠心病的重要方法.对比常规导管法冠状动脉造影,CCTA能无创提供冠状动脉病变与否的证据,更容易被广大患者所接受.然而,现阶段CCTA具有阴性预测值高、阳性预测值低、时间分辨率低以及辐射性损害四大特征,因此对医患双方又是一把"双刃剑".在临床实践中,我们应当充分发挥CCTA的优势,尽可能避免其不足,从而保证CCTA在我国规范化开展和健康发展.     

Future of cardiac computed tomography

Coronary computed tomography angiography (CCTA) has become an integral tool in the noninvasive diagnostic workup of patients with suspected coronary artery disease in both elective and emergency settings. Today, it represents a mature technique providing accurate, non-invasive morphological assessment of the coronary arteries and atherosclerotic plaque burden. Iterative reconstruction algorithms, low kV imaging, and single-heart beat acquisitions hold promise to further reduce dose requirements and improve the safety and robustness of the technique in several circumstances including imaging of heavily calcified vessels, patients with morbid obesity or irregular heart rates, and assessment in the emergency setting. However, it has become clear over recent years that cardiac radiologists need to take further steps towards the development and integration of functional imaging with morphological CCTA assessment to truly provide a comprehensive evaluation of the heart. Computed tomography myocardial perfusion imaging, including both dynamic and static dual-energy approaches, has demonstrated the ability to directly assess and quantify myocardial ischemia with simultaneous CCTA acquisition with a reasonable contrast medium volume and radiation dose delivered to the patient. In order to promote CCTA in the clinical and research environments, radiologists should prepare to embrace the change from morphological to functional imaging, furnishing all the necessary resources and information to referring clinicians.     

Coronary atherosclerosis imaging by CT to improve clinical outcomes

Coronary artery disease remains an important cause of morbidity and mortality world-wide. Coronary Computed Tomography Angiography (CCTA) has excellent diagnostic accuracy and the identification and stratification of coronary artery disease is associated with improved prognosis in multiple studies. Recent randomized controlled trials have shown that in patients with stable coronary artery disease, CCTA is associated with improved diagnosis, changes in investigations, changes in medical treatment and appropriate selection for revascularization. Importantly this diagnostic approach reduces the long-term risk of fatal and non-fatal myocardial infarction. The identification of adverse plaques on CCTA is known to be associated with an increased risk of acute coronary syndrome, but does not appear to be predictive of long-term outcomes independent of coronary artery calcium burden. Future research will involve the assessment of outcomes after CCTA in patients with acute chest pain and asymptomatic patients. In addition, more advanced quantification of plaque subtypes, vascular inflammation and coronary flow dynamics may identify further patients at increased risk.     

The rationale for the primacy of coronary CT angiography in the National Institute for Health and Care Excellence (NICE) guideline (CG95) for the investigation of chest pain of recent onset

The National Institute for Health and Care Excellence (NICE) provides independent evidence-based guidance for England's National Health Service. Its 2010 guideline for the “assessment and diagnosis of recent onset chest pain or discomfort of suspected cardiac origin” (CG95) recommended a variety of first-line investigations in stable patients, depending on the pre-test probability (PTP) of obstructive coronary artery disease (CAD). Following a limited review, NICE produced an updated version of CG95 in 2016. Formal calculation of PTP is no longer advised. Coronary computed tomographic angiography (CCTA) is recommended as the first-line investigation for all patients with angina (or non-anginal pain but an abnormal electrocardiogram) and no prior CAD, with second-line functional imaging if the CCTA is equivocal.Notwithstanding some controversies regarding NICE's methodology, the updated version of CG95 can be justified on several levels. The focus on angina reflects evidence that patients with non-anginal pain have a similar prevalence of CAD to an asymptomatic population, and may not benefit from further investigation. The elimination of PTP is reasonable in patients required to have cardiac-sounding (anginal) symptoms. The ability of CCTA to identify non-obstructive atheroma, invisible to functional testing, might lead to improved medical treatment. Conversely the argument sometimes made for first-line functional testing, that ischemia-guided coronary revascularization leads to improved outcomes, has little hard evidence to support it. The performance of a separate functional test following equivocal CCTA may improve diagnostic specificity, and similar information is now obtainable from the CT study itself via computational flow dynamics.     

Economic analysis of clinical positron emission tomography of the heart with rubidium-82

This report describes a cost analysis for clinical positron emission tomography (PET) of the heart using generator produced rubidium-82 (82Rb). Considered sequentially are the clinical problem, current noninvasive radionuclide methods, positron emission tomograph, and the cost of PET per study. Also analyzed are the costs of PET versus thallium imaging in the management of chest pain, for screening asymptomatic men at high risk for coronary artery disease and for evaluating myocardial viability after myocardial infarction or thrombolytic therapy. Noninvasive assessment of coronary artery stenosis and myocardial ischemia/viability in symptomatic or asymptomatic subjects remains a major medical problem because the sensitivity and specificity of thallium imaging are only 70-85% and 50-70%, respectively, in recent studies. Cardiac positron imaging has an accuracy for noninvasive diagnosis of coronary artery disease in symptomatic or asymptomatic patients with a sensitivity and specificity of 95-98%. It can also be used for assessing physiologic stenosis severity, for imaging myocardial infarction and viability, for assessing effects of interventions such as thrombolysis, percutaneous transluminal coronary angioplasty (PTCA) or bypass surgery on myocardial perfusion, metabolism or coronary flow reserve, for assessing collateral function noninvasively in man, and for diagnosing cardiomyopathy not due to coronary artery disease. Although the cost for cardiac PET with 82Rb may be modestly higher than for 201Tl, the greater diagnostic yield of PET results in comparable or lower overall medical management costs than no diagnostic tests/interventions and lower overall costs compared to thallium imaging for evaluating patients with chest pain, asymptomatic high risk males, and patients after acute myocardial infarction/thrombolysis for myocardial viability.     

The evolving role of coronary CT angiography in Acute Coronary Syndromes

In the United States, non-obstructive coronary disease has been on the rise, and each year, nearly one million adults suffer myocardial infarction, 70% of which are non-ST-segment elevation myocardial infarction (NSTEMI). In addition, approximately 15% of patients suffering NSTEMI will have subsequent readmission for a recurrent acute coronary syndrome (ACS). While invasive angiography remains the standard of care in the diagnostic and therapeutic approach to these patients, these methods have limitations that include procedural complications, uncertain specificity in diagnosis of the culprit lesion in patients with multi-vessel coronary artery disease (CAD), and challenges in following coronary disease over time. The role of coronary computed tomography angiography (CCTA) for evaluating patients with both stable and acute chest pain has seen a paramount upshift in the last decade. This paper reviews the established role of CCTA for the rapid exclusion of obstructive plaque in troponin negative acute chest pain, while exploring opportunities to address challenges in the current approach to evaluating NSTEMI.     

Comparative use of radionuclide stress testing, coronary artery calcium scanning, and noninvasive coronary angiography for diagnostic and prognostic cardiac assessment

Noninvasive cardiac imaging has undergone a recent resurgence with the development of new approaches for imaging coronary atherosclerosis. Non-contrast computed tomography (CT) for imaging the extent of coronary artery calcification (CAC) and contrast CT for noninvasive coronary angiography (CTA) are developments with a growing evidence base regarding risk assessment and the diagnosis of obstructive coronary disease. This review discusses the role of CAC for risk assessment of asymptomatic individuals and for the use of coronary CTA in symptomatic patients. By comparison, gated myocardial perfusion scintigraphy (MPS) is a well-established noninvasive imaging modality that is a core element in evaluation of patients with stable chest pain syndromes. Stress MPS is the most commonly used stress imaging technique for patients with suspected or known coronary disease. In contrast to the nascent evidence noted with coronary CTA, MPS has a robust evidence base, including the support of numerous clinical guidelines. We highlight the current evidence supporting the diagnostic accuracy and risk stratification data for MPS for symptomatic patients with known or suspected coronary artery disease. It is likely that assessing the extent of atherosclerosis using CAC or coronary CTA will become an increasing part of mainstream cardiovascular imaging practices. In some patients, further ischemia testing with MPS will be required. Similarly, in some patients referred for MPS, anatomic definition of atherosclerosis using CAC by CT may be appropriate. Thus, this review also provides a synopsis of the available literature on imaging that integrates both CT and MPS in combined strategies for the assessment of atherosclerotic and obstructive coronary disease burden. We also propose possible risk-based strategies through which imaging might be used to identifying candidates for more intensive prevention and risk factor modification strategies as well as those who would benefit from referral to coronary angiography and revascularization.     

Cost analysis of diagnostic testing for coronary artery disease in women with stable chest pain

BACKGROUND: Seven clinical sites compiled data from 4638 women who were referred directly to coronary angiography (catheterization-first strategy; n = 3375) or who underwent stress myocardial perfusion imaging (MPI) first (n = 1263) followed by coronary angiography if at least one reversible myocardial perfusion abnormality was detected. The study examines the cost minimization potential of these available invasive and noninvasive diagnostic strategies in women with chest pain. METHODS AND RESULTS: Women in both groups were subclassified by the core laboratory as being at low (<0.15), intermediate (0.15 to 0.60), or high (>0.60) pretest likelihood for coronary artery disease (CAD). Among the catheterization-first patients, at least one coronary stenosis >70% was present in 13% of low likelihood patients, 29% of intermediate likelihood patients, and 52% of patients with high CAD likelihood. Perfusion abnormality rates in the MPI-first group were 23% in low likelihood patients, 27% in intermediate likelihood patients, and 34% in high CAD likelihood patients. Of the MPI-first subset, 50%, 55%, and 76%, respectively, underwent catheterization in at least one coronary stenosis >70%. Cardiac death rates ranged from 0.5% to 2.2% in patients with CAD and did not differ from the 2 testing strategies (P = not significant). The composite cost per patient of diagnostic testing plus follow-up medical care over a period of 2.5 +/- 1.5 years (calculated for both strategies from inflation-corrected Medicare charges, adjusted for institutional cost-charge ratios) ranged from $2490 for patients with low likelihood to $3687 for patients with high likelihood with the catheterization-first strategy and from $1587 to $2585 for patients undergoing MPI first (P < .01 between risk subsets and strategies). CONCLUSIONS: In women referred for diagnostic evaluation of stable chest pain, MPI followed by selective coronary angiography in patients with at least 1 perfusion abnormality minimizes the near-term composite cost per patient compared with a direct catheterization-first strategy, regardless of pretest CAD likelihood.     

What is the role of calcium scoring in the age of coronary computed tomographic angiography?

Non-contrast-enhanced CT for coronary artery calcification (CAC) as a marker of coronary atherosclerosis has been studied extensively in the primary prevention setting. With rapidly evolving multidetector CT technology, contrast-enhanced coronary CT angiography (CCTA) has emerged as the non-invasive method of choice for detailed imaging of the coronary tree. In this review, we systematically evaluate the role of CAC testing in the age of CCTA in both asymptomatic and symptomatic patients, across varying levels of risk. Although the role of CAC testing is well established in asymptomatic subjects, its use in evaluating those with stable symptoms that represent possible obstructive coronary artery disease is controversial. Nevertheless, available data suggest that in low-to-intermediate risk symptomatic patients, CAC scanning may serve as an appropriate gatekeeper to further testing with either CCTA (if no or only mild CAC present) versus functional imaging or invasive coronary angiography (when moderate or severe CAC present). Given the strong short-term prognostic value of CAC?=?0, studies are needed to further evaluate the role of CAC scanning in low-risk patients with acute chest pain presenting to the emergency room.     

The Journal of Cardiovascular Computed Tomography year in review - 2018

Since the introduction of ≥64 detector row coronary computed tomography angiography (CCTA) as a noninvasive imaging modality, various clinical trials have established its diagnostic performance and prognostic significance when compared to other anatomic and functional tests for coronary artery disease (CAD). CCTA has been increasingly utilized for a wide range of clinical scenarios, driven by both advances in technology as well as data showing improvement in outcomes. Accumulating evidence has continually refined and supported the central role of CCTA within clinical care, and this year has witnessed continued evolution of the application of CCTA within healthcare and translational research. The purpose of the present review is to summarize the year of the Journal of Cardiovascular Computed Tomography (JCCT), highlighting the evidence base supporting the appropriate application of cardiac computed tomography across numerous clinical domains.     

Diagnosing coronary artery disease with hybrid PET/CT: It takes two to tango

The noninvasive diagnosis of coronary artery disease (CAD) is a challenging task. Although a large armamentarium of imaging modalities is available to evaluate the functional consequences of the extent and severity of CAD, cardiac perfusion positron emission tomography (PET) is considered the gold standard for this purpose. Alternatively, noninvasive anatomical imaging of coronary atherosclerosis with coronary computed tomography angiography (CCTA) has recently been successfully implemented in clinical practice. Although each of these diagnostic approaches has its own merits and caveats, functional and morphological imaging techniques provide fundamentally different insights into the disease process and should be considered to be complementary rather than overlapping. Hybrid imaging with PET/CT offers the possibility to evaluate both aspects nearly simultaneously, and studies have demonstrated that such a comprehensive assessment results in superior diagnostic accuracy, better prognostication, and helps in guiding clinical patient management. The aim of this review is to discuss the value of stand-alone CCTA and PET in CAD, and to summarize the available data on the surplus value of hybrid PET/CT including its strengths and limitations.