Computerized left ventricular regional ejection fraction analysis for detection of ischemic coronary artery disease with multidetector CT angiography

Regional ejection fraction (REF) provides important functional information of the left ventricular regional myocardium. We aimed to test the diagnostic accuracy of computerized REF analysis for detecting the ischemia and significant stenosis with multidetector CT angiography (MDCT). This is a retrospective study including 155 patients who underwent MDCT scans for evaluation of coronary artery disease. Among them, 83 patients also underwent SPECT imaging and invasive coronary angiography (ICA). Two groups of patients were defined: Control group with 0 coronary artery calcium and normal global and regional ventricular function, and comparison group. REF measurement was performed on all patients using computerized software. Control group REF measurements will be used as reference standard (mean-2SD REF/mean global ejection fraction) to define abnormal REF. The sensitivity, specificity, positive and negative predictive value of REF in detecting perfusion defects (fixed and reversible) was 73, 80, 75 and 79 % respectively, in a patient based analysis of comparison group. The diagnostic accuracy of REF in predicting significant stenosis (>50 %) on ICA compared with SPECT was 72 versus 61 % and 85 versus 79 % in patient and vessel based analysis of comparison group, respectively. ROC curve analysis showed REF to be a better predictor of perfusion defects on SPECT compared with significant stenosis (>50 %) alone or stenosis combined with REF (P < 0.05). The computerized assessment of REF analysis is comparable to SPECT in predicting ischemia and a better predictor of significant stenosis than SPECT. This study also provides reference standard to define abnormal values.     

Multifocal coronary artery myocardial bridging involving the right coronary and left anterior descending arteries detected by ECG-gated 64 slice multidetector CT coronary angiography

Myocardial bridging is a congenital condition in which a segment of a major epicardial coronary artery has an intramyocardial course. Myocardial bridging is usually confined to a single vessel (typically the mid segment of the left anterior descending artery) and is usually asymptomatic, however, bridging may be associated with chest pain, myocardial infarction, or sudden cardiac death. While more commonly identified at autopsy, myocardial bridging is occasionally diagnosed by coronary angiography with identification of concomitant myocardial bridging involving both the left and right coronary arteries appearing to be uncommon. We present three patients presenting with atypical chest pain symptoms in whom concomitant right coronary artery and left anterior descending artery myocardial bridging was identified by ECG gated multidetector computed tomography (MDCT).     

多层CT血管成像诊断中国冠心病人群中冠状动脉狭窄准确性的Meta分析

目的运用Meta分析方法评价多层CT诊断中国冠心病人群冠状动脉狭窄的准确性。方法在主要中文数据库中,检索有关16层及16层以上CT对比冠状动脉造影诊断冠状动脉疾病价值的文章,选择适宜效应模型合并研究结果。结果共纳入112篇符合标准的文献,研究对象计7795例,血管节段计63 789段,以血管节段为基础的汇总敏感度、特异度、OR值及sROC曲线下面积分别为0.89、0.97、238.83和0.9881。结论多层CT在中国冠心病人群的冠状动脉疾病中具有很高的诊断准确性,其高度的特异性可作为冠状动脉病变的排除性诊断。     

冠状动脉迂曲患者冠状动脉CT成像和左心室功能分析

目的探讨冠状动脉迂曲与左心室功能受损之间关系。方法收集36例CT检查冠状动脉迂曲无狭窄的患者和36例冠状动脉CT正常的患者,分析比较两组患者的临床特点和超声心动图左心功能各项指标。结果冠状动脉迂曲节段以右冠状动脉后降支、左心室后支、前降支远段及回旋支远段多见,2支病变同时发生14例(38.9%),3支及以上病变7例(19.4%);冠状动脉迂曲组与冠状动脉正常组比较超声心动图二尖瓣口舒张早期血液峰值速度(E)峰减低(63.47±5.03)cm/s vs(84.92±6.57)cm/s(P<0.01),舒张晚期血液峰值速度(A)峰升高(80.36±5.74)cm/s vs(67.36±5.75)cm/s,E/A比值0.94±0.23vs 1.22±0.14,迂曲患者室间隔厚度(11.37±0.90)mm vs(10.57±0.92)mm(P<0.01)和左心室后壁厚度(10.79±0.81)mm vs(10.16±0.86)mm(P<0.01)也较冠状动脉正常组增厚。结论冠状动脉迂曲以右冠状动脉后降支、左心室后支、左冠状动脉前降支远段及回旋支远段多见;冠状动脉迂曲患者多有左心室舒张功能减低。     

核素心肌灌注显像与多层螺旋CT血管成像对心肌桥的对比分析

目的探讨99 Tcm-MIBI心肌灌注显像对心肌桥的临床价值。方法回顾性分析105例冠状动脉CTA诊断为心肌桥并接受运动及静息99 Tcm-MIBI心肌灌注显像的患者资料,分析心肌灌注显像结果,并与冠状动脉CTA结果进行比较。结果 105例心肌桥患者中,根据Nobel分级法,Ⅰ级狭窄21例,Ⅱ级狭窄24例,Ⅲ级狭窄60例;其中60例出现心肌缺血改变。缺血组与非缺血组心肌桥患者冠状动脉CTA显示狭窄程度的差异有统计学意义(χ2=61.731,P<0.001)。不同部位心肌桥血管支发生异常灌注的差异无统计学意义(χ2=3.588,P=0.166)。结论 99 Tcm-MIBI心肌灌注显像能够用于评价冠状动脉心肌桥。     

负荷动态CT心肌灌注结合冠状动脉CT血管成像对冠心病心肌缺血的诊断价值观察

目的探讨负荷动态CT心肌灌注结合冠状动脉CT血管成像对冠心病心肌缺血的诊断价值。方法选取2017年4月至2019年4月收治的96例冠心病心肌缺血患者为研究对象,随机将其等分为研究组和对照组,对照组采取冠状动脉CT血管成像检查,研究组采取负荷动态CT心肌灌注结合冠状动脉CT血管成像检查,比较两组使用造影剂剂量及放射剂量,斑块导致管腔狭窄比例、斑块长度以及诊断率。结果研究组患者造影剂剂量、放射剂量均明显低于对照组,差异有统计学意义(P<0.05);研究组患者斑块导致管腔狭窄比例、斑块长度、诊断率均明显高于对照组,差异有统计学意义(P<0.05)。结论冠心病心肌缺血患者联合应用冠状动脉CT血管成像与负荷动态CT心肌灌注,可在降低造影剂和放射剂量的情况下,明确冠状动脉狭窄和斑块病变情况,提高对疾病的临床诊断价值。     

64排螺旋CT心肌灌注显像评价冠状动脉狭窄对心肌缺血的诊断效能

目的 利用99mTc-MIBI心肌灌注显像(MPI)探讨64排螺旋CT冠状动脉造影(CTCA)发现的冠状动脉狭窄对心肌缺血的诊断效能.方法 30例患者接受MPI和CTCA检查.将CTCA三支冠状动脉分为12段,以MPI为诊断标准,分别以CTCA血管狭窄≥50%和≥75%为截断值,统计对应节段MPI是否出现异常,分析CTCA诊断的冠状动脉狭窄对心肌缺血的效能评价.结果 MPI发现灌注异常9例(6例可逆性,3例固定性血流灌注减低).CTCA共分析327个冠状动脉节段,其中狭窄≥50%者占25段(7.65%);狭窄≥75%者12段(3.67%).以MPI异常为标准观察病变血管,以狭窄≥50%为界值时,CTCA的敏感性、特异性、阴性预测值(NPV)、阳性预测值(PPV)和准确性分别是68.42%、96.14%、99.01%、52.00%和95.41%;以狭窄≥75%为界值,则分别为66.67%、99.04%、98.73%、66.67%、97.55%.以MPI异常为标准观察患者,当血管狭窄≥50%为界值时,CTCA 的敏感性、特异性、NPV、PPV和准确性分别是66.67%、57.14%、80.00%、40.00%和60.00%;当≥75%为界值时,上述指标分别是55.56%、85.71%、81.82%、62.50%和76.67%.结论 正常CTCA对心肌缺血患者的排查是可靠的,CTCA异常是否存在心肌缺血需要进一步检查.     

Non-invasive assessment of atherosclerotic coronary lesion length using multidetector computed tomography angiography: comparison to quantitative coronary angiography

Multidetector computed tomography angiography (CTA) provides information on plaque extent and stenosis in the coronary wall. More accurate lesion assessment may be feasible with CTA as compared to invasive coronary angiography (ICA). Accordingly, lesion length assessment was compared between ICA and CTA in patients referred for CTA who underwent subsequent percutaneous coronary intervention (PCI). 89 patients clinically referred for CTA were subsequently referred for ICA and PCI. On CTA, lesion length was measured from the proximal to the distal shoulder of the plaque. Quantitative coronary angiography (QCA) was performed to analyze lesion length. Stent length was recorded for each lesion. In total, 119 lesions were retrospectively identified. Mean lesion length on CTA was 21.4 ± 8.4 mm and on QCA 12.6 ± 6.1 mm. Mean stent length deployed was 17.4 ± 5.3 mm. Lesion length on CTA was significantly longer than on QCA (difference 8.8 ± 6.7 mm, P < 0.001). Moreover, lesion length visualized on CTA was also significantly longer than mean stent length (CTA lesion length-stent length was 4.2 ± 8.7 mm, P < 0.001). Lesion length assessed by CTA is longer than that assessed by ICA. Possibly, CTA provides more accurate lesion length assessment than ICA and may facilitate improved guidance of percutaneous treatment of coronary lesions.     

冠状动脉造影与多层螺旋CT冠脉成像在心肌桥诊断中的价值

目的：探讨多层螺旋CT冠脉成像（CCTA）与冠状动脉造影（CAG）在心肌桥（M B）诊断中的价值。方法：回顾性分析疑诊冠状动脉疾病的406例均进行CCTA和CAG检查者,两组采用双盲法CCTA和CAG分别独立阅片,由2名有经验的放射科医生与2名有经验的心内科介入医生采用单盲法阅片,经讨论后共同给出诊断。相互参照另一种检查结果后再次阅片,2次检出率,应用χ^2统计分析方法,判断2种方法发现M B有无差异。结果：双盲法CCTA发现M B 19例26段,CAG发现5例5段（P〈0.01）,差异有统计学意义。相互对照后再次评价,CCTA发现M B数量同前,CAG新发现3例,将新检出的3例患者行腺苷负荷核素心肌显像,相应节段心肌出现心肌低灌注,位置与CCTA一致,共检出8例,2种方法差异有统计学意义（P〈0.05）。结论：CCTA对M B和壁冠状动脉显示清晰,较CAG有更高的检出率,容易发现M B,有着特殊的临床诊断价值。     

门控心肌灌注显像对冠状动脉支架术前后左室功能的评价

目的:比较99mTc-MIBI门控心肌灌注显像(G-MPI)测定冠脉支架术前后左心功能相关指标的变化,对手术疗效进行评价。方法:27例患者,术前及术后1~6个月行静息G-MPI测定左室舒张末期容量(EDV)、收缩末期容量(ESV)、左室射血分数(LVEF)并对室壁运动评分。根据术前LVEF分为2组:伴左室功能不全(LVEF≤45%)为Ⅰ组(12例),其余为Ⅱ组(15例)。结果:①Ⅰ组术后EDV、ESV比术前明显减少(P<0.01),LVEF增加(P<0.05);Ⅱ组上述指标手术前后无明显变化(P>0.05)。②术前室壁运动轻中度下降的节段术后82.3%有改善;严重下降29.3%有改善;无运动术后仅15.7%有改善。结论:静息G-MPI在冠脉支架术前及术后随访有重要的临床价值。     

Quantitative assessment of left ventricular perfusion defects using real-time three-dimensional myocardial contrast echocardiography.

Quantitative assessment of perfusion defects with myocardial contrast echocardiography can be a valuable tool in the evaluation of patients with coronary artery disease. However, the use of 2-dimensional echocardiography for this purpose is limited to a restricted number of imaging planes. Real-time 3-dimensional echocardiography (RT3D) is a novel technique that provides instantaneous volumetric images. The aim of this study was to validate the use of RT3D for the quantitative assessment of myocardial perfusion defects in a model of acute coronary occlusion. To this end, 20 sheep underwent acute ligation of the left anterior descending (n = 14) or the posterior branch of the circumflex (n = 6) artery under general anesthesia. The RT3D images were obtained after left atrial injection of the contrast agent EchoGen (perflenapent emulsion; 0.8-1 mL). Evans blue dye was injected into the occluded coronary artery for subsequent anatomic identification of underperfused myocardium. The mass of the entire left ventricle and of the underperfused myocardial region were measured after death. Blinded off-line calculation of left ventricular (LV) mass and perfusion-defect mass from RT3D images were performed using an interactive aided-manual tracing technique. Total LV mass ranged from 68 to 141 g (mean plus minus SD: 92 +/- 24 g). The mass of the perfusion defect ranged from 0 to 43 g (mean +/- SD: 16 +/- 9 g) or 0 to 36% of total LV mass (mean +/- SD: 18% +/- 9%). The RT3D estimation of total LV mass strongly correlated with the anatomic measurement (r = 0.91; y = -2.54 + 1.04x; standard error of the estimate [SEE] = 11.9 g). The RT3D calculation of the mass of underperfused myocardium also strongly correlated with the anatomic measurement, both in absolute terms (r = 0.96; y = 2.01 + 0.87x; SEE = 2.2 g) and when expressed as percentage of total LV mass (r = 0.96; y = 0.11 + 1.02x; SEE = 2.8%). Hence, RT3D with myocardial contrast opacification accurately predicts the amount of underperfused myocardium in an animal model of acute coronary occlusion. This technique may therefore be useful for the quantitative assessment of myocardial perfusion defects in patients with coronary artery disease.     

CT冠状动脉成像与冠状动脉导管造影评估冠状动脉钙化所致狭窄程度的一致性

目的 探讨CT冠状动脉成像(CTCA)与冠状动脉导管造影(ICA)评估冠状动脉钙化狭窄程度的一致性。方法 选取接受CTCA和ICA、且图像无明显伪影的45例冠状动脉钙化狭窄患者;分别测量其病灶处钙化CT值、血管CT值,计算二者的CT比值,即血管钙化CT比值=病灶周围钙化最高CT值/病灶周围血管近端无钙化层面的血管CT值。以所用患者血管钙化CT比值的总平均值为分界值,将病例分为A、B两组。分别比较两组中CTCA与ICA诊断冠状动脉钙化狭窄程度的一致性。结果 45例患者血管钙化CT比值的总平均值为3.04±0.89;A组血管钙化CT比值<3.04,共21例,CTCA与ICA对其狭窄程度评估的吻合率为95.24%(20/21),诊断一致性极好(Kappa=0.82,P<0.05);B组血管钙化CT比值≥3.04,共24例,CTCA与ICA对其狭窄程度评估的吻合率为37.50%(9/24),诊断一致性差(Kappa=0.172,P<0.05)。结论 当血管钙化CT比值<3.04时,采用CTCA评估冠状动脉钙化狭窄程度,与ICA的评估结果具有较好的一致性。     

Impact of luminal density on plaque classification by CT coronary angiography

Non-invasive coronary CT angiography (CCTA) has the potential to characterize the composition of non-calcified coronary plaques. CT-density values characterized by Hounsfield Units (HU) may classify non-calcified plaques as fibrous or lipid-rich, but the luminal density caused by the applied contrast material influences HU in the plaques in vitro. The influence of luminal density on HU in non-calcified plaques in vivo is unknown. Hence the purpose of this study was to test whether plaque characterization by CCTA in vivo depends on luminal density. Two CCTA-scans using two different contrast protocols were obtained from 14 male patients with coronary artery disease. The two contrast protocols applied resulted in high and low luminal density. Eleven non- calcified and 13 calcified plaques were identified and confirmed by intravascular ultrasound. Luminal attenuation differed with the two contrast protocols; 326[284;367] vs. 118[103;134] HU (P < 0.00001). In non-calcified plaques mean HU-values was lower 48[28;69] vs. 11[−4;25] HU (P = 0.004) with the low density protocol. As a consequence three out of eleven non-calcified plaques (27%) were reclassified from fibrous (high) to lipid rich (low). For calcified plaques a less pronounced but still significant difference in HU-values was found with the low luminal density. 770[622;919] vs. 675[496;855] HU (P = 0.02). Conclusion: Non-calcified plaques can be identified and classified by CCTA. However, the luminal density affects the absolute HU of both non-calcified and calcified plaques. Characterization and classification of non-calcified plaques by absolute CT values therefore requires standardization of contrast protocols.     

面罩吸氧对CT冠状动脉成像呼吸运动伪影的影响

目的评价面罩吸氧对多层螺旋CT冠状动脉成像(冠脉CTA)影像质量的影响。方法将100例患者随机分为研究组和对照组。研究组经面罩持续吸入纯氧,对照组经面罩持续吸入空气。比较2组患者左前降支和右冠状动脉的影像质量。结果研究组影像质量明显优于对照组(P0.01),但2组冠状动脉血管节段显示率无显著差异(P=0.897)。结论采用面罩吸氧能够获得较好的冠脉CTA检查成功率及图像质量。     

双源CT冠状动脉造影心肌桥-壁冠状动脉的CT表现

目的：探讨双源CT（DSCT）冠状动脉造影对心肌桥-壁冠状动脉（MB-MCA）的检出率及其形态学特征。材料与方法：应用DSCT对470例患者行冠状动脉造影,测量MB的长度、厚度及MCA受压缩程度,用均数±标准差表示;观察记录MCA近段、远段邻近血管及MCA本身的形态变化。用Pearson等级相关检验、Wilcoxon秩和检验作统计学分析。结果：①MB-MCA检出率为27.9%（131/470）,MB平均长度为（20.8±9.0）mm,MB的平均厚度为（2.3±1.1）mm,MCA平均受压缩程度为（37.8±16.9）%;MCA受压缩程度与MB厚度呈正相关（r=0.60,P=0.000）,与MB的长度无相关性（r=0.21,P=0.540）。MB的厚度与MCA长度无相关性（r=0.18,P=0.101）。②62.7%（82例）MB-MCA桥前段或/和桥后段血管走行迂曲成角,且与MB的厚度相关（z=-3.15,P=0.002）,而与MB的长度无相关性（z=-0.41,P=0.967）。③67例MCA在收缩期呈圆锥状改变,舒张期这种改变明显减轻或消失。经统计学分析,MCA的这一表现与MB的厚度、长度均有相关性（z=-2.91,P＝0.004;z=-2.61,P＝0.009）。④46例MCA相邻的血管有动脉硬化征象,经统计学分析,MCA相邻血管有动脉硬化征象组与MB的厚度、长度均有相关性（z=-3.42,P＝0.001;z= -2.89,P＝0.004）。结论：DSCT可正确诊断MB-MCA的存在,并可判断MB-MCA的形态特征,为临床诊断和治疗提供了丰富的有价值的信息。     

Thebesian valve imaging with electron beam CT angiography: implications for resynchronization therapy

We report visualization of a prominent coronary sinus os valve (Thebesian valve), by electron beam computed tomographic angiography, which impeded an endocardial approach to left ventricular pacing. Resynchronization therapy was therefore performed with an epicardial approach to left ventricular lead placement. Electron beam computed tomographic angiography can provide detailed information for coronary sinus instrumentation, including anomalies potentially affecting the approach to resynchronization therapy.     

Thebesian valve imaging with electron beam CT angiography: implications for resynchronization therapy

We report visualization of a prominent coronary sinus os valve (Thebesian valve), by electron beam computed tomographic angiography, which impeded an endocardial approach to left ventricular pacing. Resynchronization therapy was therefore performed with an epicardial approach to left ventricular lead placement. Electron beam computed tomographic angiography can provide detailed information for coronary sinus instrumentation, including anomalies potentially affecting the approach to resynchronization therapy.     

Low radiation dose imaging of myocardial perfusion and coronary angiography with a hybrid PET/CT scanner

Objectives: To test the image quality and feasibility of a sequential low radiation dose protocol for hybrid cardiac PET/CT angiography (CTA). Background: Multidetector computed tomography (MDCT) is a non‐invasive method for coronary angiography. The negative predictive value of MDCT is high but perfusion imaging has a role in detecting functional significance of coronary lesions. This has encouraged combining these techniques. However, radiation dose is of concern. We report our first experiences with a low dose sequential CTA mode applicable to hybrid imaging. Methods: In the first phase, 10 consecutive cardiac MDCT angiographies were performed with spiral acquisition and compared in terms of image quality and dose with the following 10 patients performed with a new sequential mode. In the second phase, feasibility and radiation dose of a combined ¹⁵O‐water rest‐stress PET perfusion/sequential CTA protocol were assessed in another group of 61 consecutive patients. Results: Mean effective radiation dose was 60% lower in the sequential group than in the spiral group (19·3 versus 7·6 mSv, P<0·001). In the second phase, the new sequential hybrid protocol proved possible in 87% of the patients given the preconditions determined by the manufacturer. Mean effective dose of the CT acquisition was 7·6 mSv and total dose from the PET/CTA hybrid study 9·5 mSv. Conclusion: Low dose PET/CT allows cardiac hybrid studies with <10 mSv. The protocol can be applied to almost nine out of 10 patients with CT image quality comparable to spiral acquisition.     

自动功能成像评价冠心病左心室缺血心肌节段

目的 观察自动功能成像（AFI）评估左心室缺血心肌节段的能力。方法 收集经CAG确诊的109例冠心病患者,根据CAG结果分为3组：Ⅰ组单支冠状动脉受累,53例;Ⅱ组,2支冠状动脉受累,28例;Ⅲ组≥3支冠状动脉受累,28例。采用AFI技术获取牛眼图,以CAG结果为金标准,计算AFI检出缺血心肌节段的敏感度、特异度及准确率。结果 AFI检出缺血心肌节段敏感度、特异度和准确率分别为Ⅰ组62.80%（206/328）、93.79%（438/467）、81.01%（644/795）,Ⅱ组72.06%（196/272）、91.38%（212/232）、80.95%（408/504）,Ⅲ组50.79%（256/504）、100%（0/0）、50.79%（256/504）,总敏感度、特异度和准确率分别为59.60%（658/1104）、92.99%（650/699）和72.55%（1308/1803）。结论 AFI检出左心室缺血心肌节段特异度较高,但敏感度较低,且随病变冠状动脉数目增多而降低。