冠状动脉CT血流储备分数在冠状动脉临界狭窄患者心肌缺血诊断中的应用

目的 评价冠状动脉无创血流储备分数（FFR-CT）对冠状动脉临界狭窄病变（冠状动脉狭窄50%～70%）心肌缺血的诊断效能,为FFR-CT在心肌缺血诊断中的临床应用提供参考。方法 67例冠状动脉临界狭窄病变患者,均行冠状动脉CT血管造影（CTA）及冠状动脉造影检查。患者均行冠状动脉血流储备分数（FFR）检查,根据FFR值评估心肌缺血情况。根据冠状动脉CTA影像数据算出FFR-CT值。采用Pearson相关分析FFR值和FFR-CT值之间的相关性。采用ROC评估FFR-CT对冠状动脉临界狭窄病变患者心肌缺血诊断的效能。结果 67例患者中FFR值≤0.8的有35例,FFR-CT值≤0.8的有26例。FFR值与FFR-CT值呈正相关（r=0.666 8,P<0.01）。共评估血管83支,FFR-CT用于心肌缺血诊断的ROC下面积为0.938(95%CI 0.890～0.985,P<0.01),诊断界值为0.8时,其对心肌缺血诊断的灵敏度87.5%、特异度95.24%、阳性预测值85.29%、阴性预测值79.63%。结论 FFR-CT值对冠状动脉临界狭窄病变患者心肌缺血具有较高的诊断...     

深脉分数在冠状动脉临界病变中的诊断价值

目的 以血流储备分数（FFR）为金标准,探讨基于国产软件DEEPVESSEL-FFR的冠状动脉CT血流储备分数（CT-FFR,即深脉分数）,对冠状动脉（冠脉）临界病变的诊断价值。方法 回顾性纳入2019年1月至2020年12月于河南省人民医院阜外华中心血管病医院行侵入性FFR检查的冠状动脉粥样硬化性心脏病（冠心病）患者17例（25支血管,血管直径均超过2.0 mm）,入选患者冠脉狭窄程度为50%～80%。采用DEEPVESSEL-FFR软件计算CT-FFR值,当CT-FFR≤0.8时认为狭窄具有血流动力学意义。计算并分析DEEPVESSEL-FFR在患者及血管水平诊断冠脉临界狭窄的准确度、敏感度、特异度、阳性预测值及阴性预测值,同时绘制受试者工作特征曲线（ROC）。结果 共纳入17例患者,25支病变血管。以FFR为金标准,DEEPVESSEL-FFR在患者水平的准确度、敏感度、特异度、阳性预测值及阴性预测值分别为84.0%、88.9%、87.5%、88.9%、87.5%。在血管水平的准确度、敏感度、特异度、阳性预测值及阴性预测值分别为88.2%、81.8%、85.7%、81.8%、85...     

基于冠状动脉CT血管造影的血流储备分数评价心肌缺血的价值

目的评价应用国产自主研发的基于CT血管造影(CTA)的血流储备分数(FFR_(CT))软件对心肌缺血的诊断价值。方法回顾性纳入2009年7月至2018年4月在北京大学第一医院行冠状动脉CTA及血流储备分数(FFR)检查的患者。使用FFR_(CT)软件计算出FFR_(CT)值,以有创的FFR值为金标准,分别从患者水平和血管水平计算出FFR_(CT)对心肌缺血诊断的准确性、敏感度、特异度、阳性预测值和阴性预测值。分别在患者水平和血管水平统计FFR_(CT)的ROC曲线下面积(AUC)。在血管水平,采用Pearson’s相关分析绘制FFR_(CT)值与FFR值的相关散点图,并绘制Bland-Altman图检验FFR_(CT)与FFR值的一致性。结果纳入患者71例,共计80支血管。患者水平FFR_(CT)的准确性为81.7%,敏感度为71.4%,特异度为91.7%,阳性预测值为89.3%,阴性预测值为76.7%;血管水平FFR_(CT)的准确性为81.3%,敏感度为67.6%,特异度为93.0%,阳性预测值为89.3%,阴性预测值为76.9%。在患者水平,FFR_(CT)用于诊断心肌缺血的ROC AUC为0.852(95%CI 0.758～0.946,P0.001),最佳诊断界值为0.805;在血管水平,FFR_(CT)用于诊断心肌缺血的ROC AUC为0.848(95%CI 0.758～0.938,P0.001),最佳诊断界值为0.805。Pearson’s相关分析显示,在血管水平,FFR_(CT)值与FFR值呈正相关(r=0.542,95%CI 0.366～0.681,P0.001)。FFR_(CT)值与FFR值的BlandAltman图显示两者具有良好的一致性。结论以FFR值为金标准,应用国产FFR_(CT)软件诊断心肌缺血有较高的准确率,具有一定的临床应用前景。     

基于减影技术的冠状动脉CT血流储备分数对钙化所致狭窄血流动力学的诊断价值

目的 探讨基于减影技术的冠状动脉CT血流储备分数(CT-FFR)诊断钙化病变所致冠状动脉血流动力学狭窄的价值。方法 前瞻性纳入2020年3月至2022年3月中国医学科学院北京协和医院就诊并确诊或拟诊冠心病患者22例,42处病变纳入分析。准备行有创冠状动脉造影检查的患者,提供减影冠状动脉CT血管造影(CCTA)检查,CCTA图像重建算法采用混合迭代重建。存在钙化所致冠状动脉中重度狭窄患者提供FFR检查,FFR值≤0.80定义为血流动力学显著狭窄。以FFR为金标准,计算CCTA、减影CCTA、CT-FFR和减影CT-FFR诊断钙化斑块所致血流动力学狭窄效能。结果 以病变为单位分析显示,4种图像中减影CT-FFR的诊断效能最高,敏感性、特异性、阳性预测值、阴性预测值和准确性分别为100.0%、62.1%、54.2%、100.0%和73.8%,ROC曲线下面积为0.83。以患者为单位分析显示,4种图像中减影CT-FFR的诊断效能最高,敏感性、特异性、阳性预测值、阴性预测值和准确性分别为100.0%、33.3%、55.6%、100.0%和63.6%,ROC曲线下面积为0.77。结论 减影CT-F...     

基于冠状动脉CT血管造影的血流储备分数对不同性质冠状动脉斑块患者发生病变特异性缺血的诊断价值

目的分析基于冠状动脉CT血管造影的血流储备分数(CT-FFR)对不同性质冠状动脉斑块患者发生病变特异性缺血的诊断价值。方法连续收集2019年12月至2021年4月在陕西省人民医院心血管内二科住院并接受选择性冠状动脉造影(CAG)检查的35例疑似冠状动脉狭窄患者及2020年7月至2021年4月在四川大学华西医院住院并接受选择性CAG检查的56例疑似冠状动脉狭窄患者为研究对象。根据冠状动脉斑块性质将所有患者分为钙化斑块组(n=14)、非钙化斑块组(n=34)和混合斑块组(n=42)。比较三组人口学资料、入院时心率、入院时血压、既往史、入院时实验室检查指标、CT-FFR及血流储备分数(FFR)。以FFR≤0.80作为诊断病变特异性缺血的“金标准”,绘制ROC曲线以评价CT-FFR对不同性质冠状动脉斑块患者发生病变特异性缺血的诊断价值;采用相关系数分析FFR与CT-FFR诊断不同性质冠状动脉斑块患者发生病变特异性缺血结果的一致性,绘制Bland-Altman图以分析CTFFR与FFR诊断不同性质冠状动脉斑块患者发生病变特异性缺血结果的差异性。结果三组年龄、入院时舒张压、有糖尿病史者占比、有高血压史者占比及入院时血肌酐(Scr)比较,差异有统计学意义(P<0.05)。以CT-FFR≤0.80诊断为病变特异性缺血。在冠状动脉钙化斑块、非钙化斑块、混合斑块患者中,CT-FFR诊断病变特异性缺血的灵敏度分别为55.55%、72.22%、75.00%,特异度分别为20.00%、81.25%、55.55%,正确率分别为42.86%、76.47%、66.67%。ROC曲线分析结果显示,CT-FFR诊断冠状动脉钙化、非钙化、混合斑块患者发生病变特异性缺血的AUC分别为0.40〔95%CI(0.07,0.73),P=0.549〕、0.75〔95%CI(0.58,0.93),P=0.011〕、0.66〔95%CI(0.48,0.84),P=0.080〕。相关性分析结果显示,FFR与CT-FFR诊断冠状动脉钙化、混合斑块患者发生病变特异性缺血结果均无线性关系(冠状动脉钙化斑块患者:R^(2)<0.01,P=0.926;冠状动脉混合斑块患者:R^(2)=0.07,P=0.102),FFR与CT-FFR诊断冠状动脉非钙化斑块患者发生病变特异性缺血结果的一致性良好(R^(2)=0.19,P=0.011)。Bland-Altman图分析结果显示,CT-FFR与FFR诊断冠状动脉非钙化斑块患者发生病变特异性缺血的所有散点基本在平均差值的95%CI内,说明两种方法检测结果差异性小。结论CT-FAR对冠状动脉非钙化斑块患者发生病变特异性缺血具有一定诊断价值,对冠状动脉钙化、混合斑块患者发生病变特异性缺血的诊断价值较低。     

CT血流储备分数不同操作者间测量一致性及诊断准确性研究

目的：评价CT血流储备分数（CT-FFR）不同操作者测量的一致性及诊断准确性。方法：前瞻性入选冠状动脉CT血管成像（CCTA）证实冠状动脉狭窄30%～90%且于1周内行冠状动脉造影及血流储备分数（FFR）测量的患者。FFR<0.8诊断为缺血。两操作者分别测量CT-FFR,计算Kappa值,评价二者测量CT-FFR诊断缺血的一致性。采用ROC曲线评价血管水平CCTA及CT-FFR对缺血病变的诊断效能。结果：共纳入152例患者173支冠状动脉血管,其中FFR<0.8血管85支（49.1%）,FFR≥0.8血管88支（50.9%）。两操作者测量CT-FFR差值为0.032(0.008,0.092);FFR<0.8血管的两操作者测量差值显著高于FFR≥0.8血管[0.078(0.016,0.128)vs. 0.013(0.007,0.048),P<0.001]。两操作者测量CT-FFR诊断缺血的Kappa值为0.86;诊断缺血的AUC分别为0.913(95%CI:0.861～0.950)和0.948(95%CI:0.903～0.976),差异无统计学意义（P=0.079...     

320排动态容积CT结合ECT预测老年前降支单支病变致血流储备分数<0.75的价值

目的以冠状动脉血流储备分数(FFR)为金标准,预测320排动态容积CT(320CT)结合ECT评价FFR0.75的准确性。方法连续入选临床诊断不稳定性心绞痛(UA)且冠脉320CT提示前降支(LAD)单支病变的老年患者72例,行ECT静息和运动负荷试验检查,二者结合与冠状动脉造影联合FFR比较,评价其预测FFR0.75的价值。结果 320CT示LAD狭窄超过50%联合ECT预测FFR0.75的敏感度为98%,特异度为86%,阳性预测值为94%,阴性预测值为95%;以320CT示LAD狭窄超过75%联合ECT预测FFR0.75的敏感度为96%,特异度为85%,阳性预测值为96%,阴性预测值为85%。结论当病变局限在LAD时,联合ECT和320排CT对预测LAD病变的功能学有较大价值,以320CT示狭窄超过50%为阳性标准时预测价值更高。     

纤维蛋白原与冠状动脉临界病变血流储备分数的相关性

目的探讨血浆纤维蛋白原水平与冠状动脉临界病变血流储备分数(FFR)的相关性及其临床意义。方法入选经冠状动脉造影检查为冠状动脉临界病变(冠状动脉狭窄程度为50%~70%)并行FFR检查的患者,根据冠状动脉FFR测得值分为FFR≥0.8组(23例)和FFR0.8组(14例)。入选患者均于入院后检测纤维蛋白原、总胆固醇、甘油三酯、尿酸、肌酐、血糖等指标。采用相关分析和ROC曲线分析纤维蛋白原与FFR的相关性。结果应用偏相关分析控制可能影响纤维蛋白原及冠状动脉血管病变的因素包括年龄、性别、血脂、血糖水平等,结果显示FFR0.8组患者血浆纤维蛋白原水平明显高于FFR≥0.8组(3.50±0.72 g/L比2.68±0.63 g/L,P0.05),纤维蛋白原水平与FFR值呈负相关(r=-0.477,P0.01);ROC曲线分析显示,最适宜的截断点为2.692 g/L,应用FFR值=0.8作为判断冠状动脉临界病变有无缺血的敏感度为92.9%,特异度为65.2%。结论血浆纤维蛋白原可用于检测冠状动脉临界病变心肌有无缺血,与冠状动脉临界病变心肌缺血程度相关,可作为预测冠状动脉临界病变心肌有无功能性缺血及支架植入的影响因素。     

冠状动脉再狭窄的定量冠状动脉造影与血流储备分数研究

目的研究二维定量冠状动脉造影(QCA)分析测量冠状动脉支架内再狭窄(ISR)临界病变各项指标与冠状动脉血流储备分数(FFR)的相关性。以FFR为金标准,从QCA分析测量ISR临界病变各指标中筛选理想的评价心肌缺血的影像学参数。方法共纳入21例患者26处ISR临界病变。所有病变均行QCA及FFR测量,依FFR值分成两组,FFR≥0.8组(病变n=16)与FFR<0.80组(病变n=10),采用相关分析和受试者工作特征曲线(ROC)分析QCA测量参数与FFR相关性。结果两组病变在直径狭窄百分比[RS%,(52.00±12.00)%vs(60.00±7.00)%]差异有统计学意义(P<0.05)。MLA、MLD及DS%与FFR呈不同程度相关性(均P<0.05),以DS%与FFR的相关性最强。以FFR≥0.80为界限值,绘制关于DS%的ROC曲线,得到曲线下面积(AUC)为0.70(P<0.01)。DS%<57.00%为截断点,预测FFR≥0.80灵敏度为70.00%,特异性为62.50%,阴性预测值为76.92%。结论在冠状动脉ISR临界病变中,MLA、MLD及DS%与FFR值存在一定的相关性,其中DS%可较准确预测冠状动脉ISR临界病变的血流储备功能。     

320排动态容积CT冠状动脉成像诊断冠状动脉狭窄的价值

目的 以冠状动脉造影作为诊断冠状动脉狭窄的金标准,评价320排动态容积CT冠状动脉成像诊断冠状动脉狭窄的准确性.方法 应用320排动态容积CT对85例可疑冠心病患者行冠状动脉成像检查,同期行冠状动脉造影.结果 320排动态容积CT冠状动脉成像可获得较好的图像质量,可用于诊断冠状动脉狭窄.320排动态容积CT诊断冠状动脉轻度狭窄的敏感度为90.9％,特异度为99.2％,阳性预测值为89.6％,阴性预测值为99.3％,准确率为98.6％;诊断冠状动脉中度狭窄的敏感度为92.8％,特异度为98.9％,阳性预测值为90.9％,阴性预测值为99.2％,准确率为98.3％;诊断冠状动脉重度狭窄的敏感度为87.4％,特异度为98.8％,阳性预测值为89.2％,阴性预测值为98.6％,准确率为97.6％;诊断冠状动脉闭塞病变的敏感度为50.0％,特异度为99.9％,阳性预测值为66.7％,阴性预测值为99.8％,准确率为99.7％;诊断冠状动脉中度以上狭窄的敏感度为94.1％,特异度为97.2％,阳性预测值为89.2％,阴性预测值为98.5％,准确率为96.6％.结论 320排动态容积CT冠状动脉成像是一种无创、有效诊断冠状动脉狭窄的方法.     

Diagnostic Performance of Machine Learning Based CT-FFR in Detecting Ischemia in Myocardial Bridging and Concomitant Proximal Atherosclerotic Disease

BackgroundThe diagnostic performance of coronary computed tomography angiography-derived fractional flow reserve (CT-FFR) in detecting ischemia in myocardial bridging (MB) has not been investigated to date.MethodsThis retrospective multicentre study included 104 patients with left anterior descending MBs. MB was classified as either superficial or deep, short, or long, whereas all MB vessels were further divided into <50%, 50% to 69%, and ≥70% groups, according to proximal lumen stenosis on invasive coronary angiography. Diagnostic performance and receiver operating characteristics (ROC) of CT-FFR to detect lesion-specific ischemia was assessed on a per-vessel level, using invasive FFR as reference standard. Intraclass correlation coefficient (ICC) and Bland-Altman plots were used for agreement measurement.ResultsForty-eight MB vessels (46.2%) showed ischemia by invasive FFR (≤0.80). Sensitivity, specificity, and accuracy of CT-FFR to detect functional ischemia were 0.96 (0.85 to 0.99), 0.84 (0.71 to 0.92), and 0.89 (0.81 to 0.94), respectively, in all MB vessels. There were no differences in diagnostic performance between superficial and deep MB or between short and long MB (all P > 0.05). The accuracy of CT-FFR was 0.96 (0.85 to 0.99) in ≥70% stenosis, 0.82 (0.67 to 0.91) in 50% to 69% stenosis, and 0.89 (0.51 to 0.99) in <50% stenosis (P = 0.081). Bland-Altman analysis showed a slight mean difference between CT-FFR and invasive FFR of 0.014 (95% limit of agreement, –0.117 to 0.145). The ICC was 0.775 (95% confidence interval, 0.685-0.842, P < 0.001).ConclusionsCT-FFR demonstrated high diagnostic performance for identifying functional ischemia in vessels with MB and concomitant proximal atherosclerotic disease when compared with invasive FFR. However, the clinical use of CT-FFR in patients with MB needs further study for stronger and more robust results.     

Incremental Value of Subtended Myocardial Mass for Identifying FFR-Verified Ischemia Using Quantitative CT Angiography: Comparison With Quantitative Coronary Angiography and CT-FFR

Objectives

This study examined the incremental value of subtended myocardial mass (V_sub) as assessed by coronary computed tomography angiography (CTA) for identifying lesion-specific ischemia verified by invasive fractional flow reserve (FFR) in quantitative coronary CTA.

瞬时无波形比值和定量血流分数评价冠状动脉临界病变准确性的对比研究

目的以血流储备分数(FFR)为标准,比较定量血流分数(QFR)和瞬时无波形比值(iFR)评估冠状动脉临界病变的准确性,并分析QFR与iFR的相关性及诊断一致率。方法回顾性纳入北京大学第三医院2015年5月至2020年6月因冠心病进行冠状动脉造影(CAG)并接受FFR和iFR检测的62例患者,收集患者的临床和CAG病变解剖学资料、靶血管iFR和FFR值,并测量同一靶血管的QFR值。以FFR≤0.80为判断心肌缺血的临界值,比较QFR和iFR与FFR评估冠状动脉临界病变的准确性,并分析QFR与iFR的相关性及诊断一致率。结果62例患者中,有53例(85.5%)靶血管为左前降支,基线直径狭窄率为48.0%(41.1%,55.7%)。iFR、QFR与FFR均具有较好的相关性[r=0.773(95%CI 0.649~0.857)、r=0.626(95%CI 0.445~0.757),均P<0.001]。QFR、iFR预测FFR≤0.80的受试者工作特征曲线下面积(AUC)比较,差异无统计学意义[0.859(95%CI 0.748~0.935)比0.875(95%CI 0.766~0.945),P=0.801];二者与FFR诊断一致率的差异无统计学意义(74.2%比79.0%,P=0.615)。QFR与iFR的相关性较弱(r=0.396,95%CI 0.162~0.587,P=0.0015)。QFR对应iFR≤0.89的AUC为0.663(95%CI 0.524~0.801,P=0.028)。QFR、iFR联合诊断策略可以与FFR达到88.7%的诊断一致率,同时减少58.1%的压力导丝使用。结论iFR与QFR评估冠状动脉临界病变具有相似的诊断准确率,但二者相关性较弱。二者联合诊断策略可进一步提高诊断准确率。     

Influence of Coronary Calcium on Diagnostic Performance of Machine Learning CT-FFR: Results From MACHINE Registry

ObjectivesThis study was conducted to investigate the influence of coronary artery calcium (CAC) score on the diagnostic performance of machine-learning–based coronary computed tomography (CT) angiography (cCTA)–derived fractional flow reserve (CT-FFR).BackgroundCT-FFR is used reliably to detect lesion-specific ischemia. Novel CT-FFR algorithms using machine-learning artificial intelligence techniques perform fast and require less complex computational fluid dynamics. Yet, influence of CAC score on diagnostic performance of the machine-learning approach has not been investigated.MethodsA total of 482 vessels from 314 patients (age 62.3 ± 9.3 years, 77% male) who underwent cCTA followed by invasive FFR were investigated from the MACHINE (Machine Learning based CT Angiography derived FFR: a Multi-center Registry) registry data. CAC scores were quantified using the Agatston convention. The diagnostic performance of CT-FFR to detect lesion-specific ischemia was assessed across all Agatston score categories (CAC 0, >0 to <100, 100 to <400, and ≥400) on a per-vessel level with invasive FFR as the reference standard.ResultsThe diagnostic accuracy of CT-FFR versus invasive FFR was superior to cCTA alone on a per-vessel level (78% vs. 60%) and per patient level (83% vs. 73%) across all Agatston score categories. No statistically significant differences in the diagnostic accuracy, sensitivity, or specificity of CT-FFR were observed across the categories. CT-FFR showed good discriminatory power in vessels with high Agatston scores (CAC ≥400) and high performance in low-to-intermediate Agatston scores (CAC >0 to <400) with a statistically significant difference in the area under the receiver-operating characteristic curve (AUC) (AUC: 0.71 [95% confidence interval (CI): 0.57 to 0.85] vs. 0.85 [95% CI: 0.82 to 0.89], p = 0.04). CT-FFR showed superior diagnostic value over cCTA in vessels with high Agatston scores (CAC ≥ 400: AUC 0.71 vs. 0.55, p = 0.04) and low-to-intermediate Agatston scores (CAC >0 to <400: AUC 0.86 vs. 0.63, p < 0.001).ConclusionsMachine-learning–based CT-FFR showed superior diagnostic performance over cCTA alone in CAC with a significant difference in the performance of CT-FFR as calcium burden/Agatston calcium score increased. (Machine Learning Based CT Angiography Derived FFR: a Multicenter, Registry [MACHINE] NCT02805621).     

Diagnostic Value of Transluminal Attenuation Gradient for the Presence of Ischemia as Defined by Fractional Flow Reserve and Quantitative Positron Emission Tomography

Objectives

The aim of this study was to investigate the incremental diagnostic value of transluminal attenuation gradient (TAG), TAG with corrected contrast opacification (TAG-CCO), and transluminal diameter gradient (TDG) over coronary computed tomography angiography (CTA)–derived diameter stenosis alone for the identification of ischemia as defined by both the invasive reference standard fractional flow reserve (FFR) and the noninvasive reference standard quantitative positron emission tomography (PET).

256层螺旋CT对冠状动脉狭窄的评估

目的：应用256层螺旋CT对冠状动脉狭窄进行评估。方法：回顾性分析126例拟诊冠心病患者行256层螺旋CT （CTA）和冠状动脉造影（CAG）检查的资料。以 CAG结果为诊断冠心病的“金标准”,分析 CTA检测冠心病的准确度、灵敏度、特异度、阴性预测值与阳性预测值,并分析二者诊断冠状动脉狭窄的一致性。结果：以CAG结果为诊断冠心病的“金标准”, CTA 检测393段冠脉节段冠状动脉狭窄的准确度为89.3％,灵敏度为91.4％,特异度为84.9％,阴性预测值为82.3％,阳性预测值为92.8％,Kappa值＝0.755,P＜0.01。结论：256层螺旋CT可较好地显示冠状动脉狭窄,作为简单易行的无创性检查,对血管狭窄诊断的敏感性高。可作为亚健康人群的早期筛查和冠心病的复查可靠方法。     

Measurement of fractional flow reserve to assess moderately severe coronary lesions: correlation with dobutamine stress echocardiography

BACKGROUND: New techniques to evaluate coronary artery disease, such as calculation of myocardial fractional flow reserve (FFR) with a guidewire and pressure transducer, provide a functional assessment of coronary lesions. The present study was designed to determine the correlation between FFR and dobutamine stress echocardiography in patients with moderately severe coronary stenosis in order to judge the usefulness of FFR for commonly encountered clinical problems. METHODS AND RESULTS: We studied 21 patients with 23 moderately severe coronary artery stenoses on angiography. The FFR was calculated and dobutamine stress echocardiography was performed to detect ischemia. Of the 16 stenoses with a negative FFR (> or = 0.75), dobutamine echocardiography also was negative. In the seven stenoses with a positive FFR (< 0.75), dobutamine echocardiography was positive in three. The efficacy of FFR in detecting ischemia that was confirmed with stress echocardiography was sensitivity 100%, specificity 80%, positive and negative predictive value 42.8%, and 100%, respectively, with a global predictive value 82.6%. A moderate degree of correlation was found between the two diagnostic tests (kappa [kappa] = 0.51). CONCLUSIONS: FFR correlates moderately well with dobutamine stress echocardiography in the assessment of moderately severe lesions in patients for whom coronary arteriography is usually indicated. However, its high negative predictive value makes FFR a useful aid in reaching clinical decisions promptly in the hemodynamics laboratory.     

CTA在不同冠心病亚组中的诊断价值

目的评价CT冠状动脉成像（CTA）在不同冠心病亚组中的诊断价值。方法分别利用CTA（采用64层螺旋CT）与冠状动脉造影（CAG）对冠状动脉狭窄程度与冠脉内斑块性质进行对比分析,评价CTA与CAG的诊断符合率,并探讨稳定型心绞痛、不稳定型心绞痛、非ST段抬高性心肌梗死的斑块性质差异及临床意义。结果与CAG相比,CTA在显示冠状动脉病变的敏感性为96．96％,特异性为93．76％,假阴性率3．04％,假阳性率为6．24％,阳性预测值90．25％,阴性预测值为98．11％;以CAG为标准,CTA在显示冠脉斑块的整体符合率为85％;稳定型心绞痛（SAP）、不稳定型心绞痛（UAP）、非sT段抬高性心肌梗死（NSTEMI）的钙化斑块比例顺次降低,而混合斑块与软斑块比例顺次升高。结论CTA与CAG的诊断符合率较高,可用于诊断冠脉病变,并可对冠脉斑块性质作出初步诊断。     

CT FFR for Ischemia-Specific CAD With a New Computational Fluid Dynamics Algorithm: A Chinese Multicenter Study

ObjectivesThe aim of this study was to validate the feasibility of a novel structural and computational fluid dynamics–based fractional flow reserve (FFR) algorithm for coronary computed tomography angiography (CTA), using alternative boundary conditions to detect lesion-specific ischemia.BackgroundA new model of computed tomographic (CT) FFR relying on boundary conditions derived from structural deformation of the coronary lumen and aorta with transluminal attenuation gradient and assumptions regarding microvascular resistance has been developed, but its accuracy has not yet been validated.MethodsA total of 338 consecutive patients with 422 vessels from 9 Chinese medical centers undergoing CTA and invasive FFR were retrospectively analyzed. CT FFR values were obtained on a novel on-site computational fluid dynamics–based CT FFR (uCT-FFR [version 1.5, United-Imaging Healthcare, Shanghai, China]). Performance characteristics of uCT-FFR and CTA in detecting lesion-specific ischemia in all lesions, intermediate lesions (luminal stenosis 30% to 70%), and “gray zone” lesions (FFR 0.75 to 0.80) were calculated with invasive FFR as the reference standard. The effect of coronary calcification on uCT-FFR measurements was also assessed.ResultsPer vessel sensitivities, specificities, and accuracies of 0.89, 0.91, and 0.91 with uCT-FFR, 0.92, 0.34, and 0.55 with CTA, and 0.94, 0.37, and 0.58 with invasive coronary angiography, respectively, were found. There was higher specificity, accuracy, and AUC for uCT-FFR compared with CTA and qualitative invasive coronary angiography in all lesions, including intermediate lesions (p < 0.001 for all). No significant difference in diagnostic accuracy was observed in the “gray zone” range versus the other 2 lesion groups (FFR ≤0.75 and >0.80; p = 0.397) and in patients with “gray zone” versus FFR ≤0.75 (p = 0.633) and versus FFR >0.80 (p = 0.364), respectively. No significant difference in the diagnostic performance of uCT-FFR was found between patients with calcium scores ≥400 and <400 (p = 0.393).ConclusionsThis novel computational fluid dynamics–based CT FFR approach demonstrates good performance in detecting lesion-specific ischemia. Additionally, it outperforms CTA and qualitative invasive coronary angiography, most notably in intermediate lesions, and may potentially have diagnostic power in gray zone and highly calcified lesions.     

64层螺旋CT冠状动脉成像在冠心病早期诊断的价值

目的 探讨64层螺旋计算机断层扫描冠状动脉成像（64-slice computed tomographic coronary angiography，CTA）早期诊断冠心病的临床价值。方法 回顾性分析行CTA和冠状动脉造影的临床疑诊冠心病病人65例，以冠状动脉造影结果为标准，评估CTA诊断冠状动脉中重度狭窄（≥50%）的准确性。结果 CTA诊断冠状动脉中、重度狭窄的敏感性、特异性、阴性预测值、阳性预测值和准确度分别为92.7%、91.7%、81.9%、96.9%和92.0%。结论 CTA诊断冠状动脉中、重度狭窄具有较高的准确性，适合用于临床怀疑冠心病的的筛选检查。