AI在CCTA诊断冠状动脉狭窄中的准确性及应用价值

目的:探讨人工智能(AI)在冠状动脉CT血管成像(CCTA)中诊断冠状动脉狭窄的准确性及应用价值。方法:收集2019年4月至10月110例同时行CCTA及有创冠状动脉造影(ICA)病人的影像资料,110例共1484段血管纳入评价范围。狭窄程度分为无狭窄、轻度狭容(<50%)、中度狭(50%~70%)重度狭窄(>70%).AI软件自动对CCTA图像进行重建及计算分析。以ICA结果为金标准,计算AI在CCTA中诊断冠状动脉狭容的敏感度、特异度、阳性预测值及阴性预测值。对AI与ICA结果进行Kappa值一致性检验。结果:①AI检出冠状动脉狭窄的敏感度、特异度、阳性预测值及阴性预测值分别为92.97%.97.91%,88.53%,96.36%,准确性为93.60%,AI与ICA检出冠状动脉狭窄一致性好(Kappa值0.86).②AI诊断冠状动脉狭窄程度准确性为66.13%,与ICA一致性一般(Kappa值0.58)。诊断轻度狭窄准确性较高,诊断中重度狭窄特异度较高。结论:AI在CCTA中对冠状动脉狭窄节段的检出及诊断轻度狭窄具有较高准确性,诊断中重度狭窄特异度较高,可作为医师辅助诊断手段.     

64层CT评价冠脉粥样斑块性质与狭窄程度的相关性

目的：探讨64层CT评价冠状动脉粥样硬化斑块性质与冠脉狭窄程度之间的相关性。方法：36例疑诊为冠心病患者行64层冠状动脉CT血管成像（CCTA）及冠状动脉血管造影（CAG）检查,以CAG为标准评价CCTA诊断冠脉狭窄程度的准确性,并诊断冠状动脉粥样硬化斑块性质,分析其与经CAG确诊的冠脉狭窄程度之间有无统计学意义。结果：36例患者中共检出105个斑块。冠脉轻度狭窄以钙化斑块引起为主,冠脉中度狭窄和重度狭窄以混合斑块引起为主。CCTA诊断冠状动脉钙化斑块与管腔轻度狭窄、混合斑块与中重度管腔狭窄存在相关性。结论：64层CCTA可在诊断冠脉狭窄的同时无创性评价斑块性质,可及时发现冠脉中脂质成分丰富的斑块,以便尽早及时给予临床干预,可降低急性冠脉综合征发生率。     

第3代双源CT低剂量Turbo Flash成像图像质量与诊断效能的临床研究

目的探讨第3代双源CT大螺距前瞻性心电门控扫描模式(Turbo Flash)冠状动脉CT成像(CCTA)评价冠状动脉狭窄的准确性、图像质量及有效辐射剂量。方法前瞻性收集2016年4月至2017年4月接受第3代双源CCTA检查的患者1003例,其中有70例患者在CCTA检查后30 d内行冠状动脉造影(CAG)。对冠状动脉各节段图像质量进行评分,计算有效辐射剂量。以CAG结果为“金标准”,计算CCTA显示冠状动脉病变的灵敏度、特异度、阳性预测值和阴性预测值;CCTA与CAG评价冠状动脉狭窄分级的一致性采用Kappa值并进行U检验。结果(1) 图像质量:右冠状动脉不可诊断血管节段为0,左冠状动脉主干及前降支不可诊断血管节段为0,左冠状动脉回旋支不可诊断血管节段为0.04% (3/835)。(2)准确性评价:基于节段水平分析,Force CT诊断冠状动脉狭窄的灵敏度为97.0% (289/298)、特异度为98.3% (706/718)、阳性预测值为96.0% (289/301)、阴性预测值为98.7% (706/715);基于血管分析,灵敏度为97.5% (159/163)、特异度为85.1% (40/47)、阳性预测值为95.8% (159/166)、阴性预测值为90.9% (40/44);基于患者分析,灵敏度、特异度、阳性预测值、阴性预测值均为100%。CCTA与CAG显示的冠状动脉狭窄部位高度一致(U=2.4,P=0.008)。(3)辐射剂量:有效辐射剂量为(1.17±0.29)mSv。结论第3代双源CT Turbo Flash模式可以在自然呼吸、无心率干预下进行冠状动脉成像,扫描成功率高,图像质量佳,评价冠状动脉狭窄的准确性高,有效辐射剂量低。     

256层CT诊断冠状动脉狭窄与CCA对照分析

目的:评价256层CT诊断冠状动脉狭窄的价值,并与常规冠状动脉造影(CCA)对照分析.方法:80例行256层CT冠状动脉造影(CCTA)及CCA检查者纳入研究.半定量分析CCTA诊断冠状动脉狭窄程度,并以CCA结果为参考标准.评估256层CT诊断冠状动脉狭窄的敏感度、特异度、阳性预测值、阴性预测值和准确性.同时分析25...     

64层螺旋CT冠状动脉成像临床应用评价

目的:评价64层螺旋CT冠状动脉成像(64SCTCA)的图像质量和在诊断冠状动脉疾病的临床价值。方法:搜集35例患者64SCTCA的完整资料,并以近期实施的选择性X线冠状动脉成像(SCA)结果为金标准进行对比,对64SCTCA显示的冠状动脉主支及主要分支情况进行分级评估。结果:35例病例可用于评估的冠状动脉共计368支,成功率达95.6%。其中SCA共显示74个节段冠脉有中、重度狭窄(≥50%)。MSCTCA诊断中重度狭窄的敏感性为86.5%,特异性为97.3%,阳性预测值88.9%,阴性预测值96.6%。经配对χ2检验,P>0.05,证明两种检查方法在发现冠状动脉病变方面差异无统计学意义。结论:64层螺旋CT冠状动脉成像是一种无创、快速的成像方法,对诊断冠状动脉≥50%狭窄有较高的敏感性和特异性,适合用于临床怀疑冠心病的患者SCA前的筛选检查。     

64层CT评价心外膜脂肪组织与冠状动脉狭窄程度的相关性

目的：采用64层MSCT评价心外膜脂肪组织厚度（EAT）与心外膜脂肪组织容积（EAV）和冠状动脉狭窄程度的关系。方法：临床拟诊为冠心病（CAD）的患者188例为研究对象,男114例,女74例,平均年龄（64.0±9.97）岁;均行心脏冠状动脉64层MSCT血管成像,在GE ADW4.4工作站分别测量左心室心尖部的脂肪组织厚度及全心外膜脂肪组织容积,并对冠状动脉狭窄程度进行定量Gensini积分。结果：本组病例共检出有冠状动脉病变的病例106例,病变178处,其中轻度狭窄组（管腔狭窄51%~75%）67例,病变125处;中度狭窄组（管腔狭窄76%~90%）21例,病变27处;重度狭窄组（管腔狭窄91%~99%）12例,病变18处;完全闭塞组（管腔狭窄100%）6例,病变8处。冠状动脉轻度、中度、重度狭窄及完全闭塞组之间的EAT和EAV差异均具有显著统计学意义（FT=32.306,FV=27.743,P=0.000）,四组之间Gensini积分差异均具有显著统计学意义（F=110.483,P=0.000）。冠状动脉狭窄的Gensini积分与EAT、EAV呈显著正相关（rT=0.739、rV=0.801,P=0.000）。结论：心外膜脂肪组织厚度、容积与冠状动脉狭窄程度呈显著正相关。     

Stent size selection using 64-detector coronary computed tomography angiography: a comparison to invasive coronary angiography

RATIONALE AND OBJECTIVES: Compare stent size selection using coronary computed tomography angiography (CCTA) to invasive coronary angiography (ICA). CCTA is increasingly performed before cardiac catheterization; however, the utility of incorporating these data into coronary interventions is unknown. METHODS: Retrospective study of 18 consecutive patients with 24 coronary artery lesions evaluated with 64-detector CCTA followed by ICA and resulting stent placement. Two blinded interventional cardiologists independently reviewed designated arterial segments on both CCTA and ICA during different reading sessions and determined anticipated stent length and nominal diameter, maximum stenosis, the need for postdilation of either stent margin, and final proximal and distal stent diameters. RESULTS: There was strong correlation between CCTA and ICA in the anticipated stent length (r = 0.85, P < .001) and final stent diameter (proximal end r = 0.74, P < .001; distal end r = 0.63, P = .001). Anticipated stent length was longer with CCTA compared to ICA (27.0 +/- 16.0 vs. 21.8 +/- 13.3 mm; P = .006). The final stent diameters were larger with CCTA compared to ICA, both at the proximal end (3.6 +/- 0.5 vs. 3.1 +/- 0.5 mm; P < .001) and distal end (3.2 +/- 0.6 vs. 2.9 +/- 0.4 mm; P = .004). CONCLUSIONS: Using 64-detector CCTA, interventional cardiologists select longer stents with larger final stent diameters than with ICA. Further studies are needed to determine the clinical utility of incorporating CCTA, when available, in defining interventional strategy.     

第二代双源CT前门控冠状动脉成像与冠状动脉造影比较的初步研究

目的:探讨第二代双源CT前门控冠状动脉成像(CTCA)对冠状动脉狭窄病变的诊断价值。方法:连续44例同期行第二代双源CT前门控CTCA(其中前门控序列扫描35例,前门控大螺距螺旋扫描9例)及选择性冠状动脉造影(SCA)检查的患者,按冠脉病变狭窄程度分为:无狭窄;轻度狭窄(狭窄≤50%);中度狭窄(狭窄50%～75%);重度狭窄(狭窄≥75%);闭塞(狭窄100%),将中度及中度以上狭窄定义为有意义狭窄。以SCA为金标准,分析第二代双源CT前门控CTCA诊断冠状动脉狭窄的敏感性、特异性、阳性和阴性预测值及准确度,同时计算第二代双源CT前门控CTCA的辐射剂量。结果:44例患者冠脉直径2mm以上的节段共570个,其中12段图像质量较差,无法评估,可评估节段占97.89%。第二代双源CT前门控CTCA按冠脉节段计算,诊断冠状动脉狭窄的敏感度、特异度、阳性和阴性预测值、准确度分别为90.18%、93.05%、76.52%、97.42%、92.47%,诊断冠状动脉有意义狭窄的敏感度、特异度、阳性和阴性预测值、准确度分别为90.14%、95.69%、75.29%、98.52%、94.98%。第二代双源CT前门控CTCA与SCA比较对冠状动脉狭窄评价的差异无统计学意义(χ2=2.10,P>0.05),对冠状动脉有意义狭窄评价的差异无统计学意义(χ2=1.46,P>0.05)。第二代双源CT前门控CT-CA的平均辐射剂量为(3.36±1.59)mSv,其中前门控序列扫描的平均辐射剂量为(3.99±1.18)mSv,前门控大螺距螺旋扫描的平均辐射剂量为(1.11±0.44)mSv。结论:第二代双源CT前门控成像对诊断冠状动脉狭窄的准确度稍低于SCA,但其阴性预测值较高,同时其辐射剂量较低,可作为临床冠心病筛查的无创性检查手段。     

Diagnostic performance of 64-slice multidetector coronary computed tomographic angiography in women

Background

Diagnostic approach to chest pain in women is challenging, but still under-investigated. The purpose of this study was to assess the diagnostic performance of 64-slice multidetector coronary computed tomographic angiography (CCTA) in women with chest pain.

Methods and Results

We included 606 patients??255 women and 351 men (mean age 61?±?12?years for both)??who had been referred for a CCTA and an invasive coronary angiography (diagnostic standard) because of chest pain, either as part of clinical work-up in two urban medical centers or as part of the multicenter ACCURACY trial. On a patient-based model, the sensitivity, specificity, and positive predictive value (PPV) and negative predictive value to detect ??50% and ??70% stenosis were 98%, 84%, 87%, and 97% and 96%, 83%, 77%, and 97%, respectively, for women and 97%, 83%, 89%, and 95% and 94%, 91%, 90%, and 94%, respectively, for men. There were no statistically significant differences between men and women in diagnostic performance measures except for the PPV of detecting a ??70% stenosis (P?=?.007).

Conclusion

In women with chest pain, 64-slice multidetector CCTA is at least as sensitive and specific as in men. Our findings suggest that CCTA is a promising diagnostic tool for timely detection and/or exclusion of CAD in symptomatic intermediate-risk female populations.     

64层螺旋CT对周围血管性疾病的诊断价值:与DSA的对照研究

目的 通过与DSA比较评估64层螺旋CT血管成像诊断周围血管性疾病(peripheral vascular disease,PVD)的准确性及特异性.方法 30例PVD患者同时接受DSA及CT血管造影检查.血管狭窄程度分为5级:Ⅰ正常(无狭窄);Ⅱ轻度狭窄(1%～49%狭窄);Ⅲ中度狭窄(50%～74%狭窄);Ⅳ重度狭窄(75%～99%);Ⅴ闭塞.以DSA结果为金标准,分析64层螺旋CT的灵敏度、特异度等指标.结果 30例患者中,共有720支血管均有DSA及CTA成像.进行分析比较后发现,64层螺旋CT诊断下肢动脉有意义狭窄的灵敏度98.5%、特异度99.2%、阳性预测值99.1%、阴性预测值98.7%.结论 64层螺旋CT血管成像是诊断周围血管狭窄程度的一种准确、安全、无创的影像学诊断技术.     

64层螺旋CT冠状动脉成像的临床应用

目的:探讨64层螺旋CT冠状动脉成像的临床应用价值。方法:对120例临床拟诊为冠心病或已确诊的冠心病患者,行64层螺旋CT血管成像,对所有原始数据采用容积再现(VR)、最大密度投影(MIP)、曲面重建(CPR)进行图像后处理,显示冠状动脉主干及主要分支。结果:心率小于70次/min且平稳时冠状动脉成像质量最佳,可较准确显示冠状动脉通畅情况、冠状动脉斑块、狭窄程度及管壁病变。对于搭桥血管及支架植入是否通畅及是否再狭窄显示良好。结论:64层螺旋CT冠状动脉成像无创、快速,对冠状动脉病变的筛选,桥血管及内支架术后疗效随访等有很大的应用价值。     

西门子128层螺旋CT诊断冠状动脉狭窄的研究

目的探讨西门子128层螺旋CT冠状动脉成像（CTA）对诊断冠状动脉狭窄的价值。方法收集来我院就诊的疑似冠状动脉狭窄患者36例,均进行128层螺旋CT冠状动脉造影检查和DSA选择性冠状动脉造影检查,观察两种检查方法中冠状动脉狭窄的影像学表现和诊断价值,并与64层以下冠状动脉CTA进行对照。结果 36例冠状动脉狭窄患者的两种检查结果,经统计学分析,西门子128层螺旋CT对冠状动脉狭窄的敏感性为98.08%、特异性为95.69%、准确性为96.43%。与64层以下螺旋CT比较,对患者心率、屏气等方面的要求更加宽松。结论西门子128层螺旋CT对冠状动脉狭窄的诊断价值高,方法简单、快速准确、无创伤,患者易接受,可作为疑似冠状动脉狭窄患者的首选检查手段。     

多层螺旋CT无创性冠状动脉造影对冠状动脉疾病的诊断价值

目的:探讨16层螺旋CT冠状动脉造影对冠状动脉病变的临床诊断价值。方法:57例疑似冠状动脉病变的患者行16排螺旋CT检查和冠状动脉造影,不包括5例为冠状动脉支架置入术后(支架12个)。将冠状动脉分为13个节段,分析所有管腔大于2mm的节段,评价图像是否能满足管腔评价。管腔狭窄大于50%认为有意义,以常规冠状动脉造影作为金标准,比较16层螺旋CT在诊断有意义的冠状动脉狭窄方面的敏感性、特异性、阳性预测值、阴性预测值。结果:在所有638个节段中,588个节段(占92.16%)能够满足冠状动脉管腔评价。对于16层螺旋CT能够显示有意义冠状动脉狭窄,与ICA相对照,若以动脉节段计数,MSCT显示中度以上狭窄的敏感性、特异性、阳性预测值、阴性预测值和准确度分别为93.61%、91.11%、89.79%、98.12%和94.63%。以动脉主干计数,MSCT显示中度以上狭窄的敏感性、特异性、阳性预测值、阴性预测值和准确度分别为92.82、、91.31%、80.43%、97.37%和82.08%。以患者计数,MSCT显示中度以上狭窄的敏感性、特异性、阳性预测值、阴性预测值和准确度分别为94.73%、90.00%、93.01%、92.99%和82.75%。结论:16层螺旋CT结合回顾性心电门控技术冠状动脉成像无创、简单易行。既能显示管腔情况又能显示冠脉管壁,弥补了ICA的不足;经严格控制影响因素,具有较高的敏感性和特异性,较高的阴性预测值可避免不必要的有创性检查。对支架术后的随访也有较高的应用价值,对血管变异的显示直观确切。可作为一种有效的筛查和随访手段应用于临床。     

The accuracy of coronary CT angiography in patients with coronary calcium score above 1000 Agatston Units: Comparison with quantitative coronary angiography

BackgroundHigh amounts of coronary artery calcium (CAC) pose challenges in interpretation of coronary CT angiography (CCTA). The accuracy of stenosis assessment by CCTA in patients with very extensive CAC is uncertain.MethodsRetrospective study was performed including patients who underwent clinically directed CCTA with CAC score >1000 and invasive coronary angiography within 90 days. Segmental stenosis on CCTA was graded by visual inspection with two-observer consensus using categories of 0%, 1–24%, 25–49%, 50–69%, 70–99%, 100% stenosis, or uninterpretable. Blinded quantitative coronary angiography (QCA) was performed on all segments with stenosis ≥25% by CCTA. The primary outcome was vessel-based agreement between CCTA and QCA, using significant stenosis defined by diameter stenosis ≥70%. Secondary analyses on a per-patient basis and inclusive of uninterpretable segments were performed.Results726 segments with stenosis ≥25% in 346 vessels within 119 patients were analyzed. Median coronary calcium score was 1616 (1221–2118). CCTA identification of QCA-based stenosis resulted in a per-vessel sensitivity of 79%, specificity of 75%, positive predictive value (PPV) of 45%, negative predictive value (NPV) of 93%, and accuracy 76% (68 false positive and 15 false negative). Per-patient analysis had sensitivity 94%, specificity 55%, PPV 63%, NPV 92%, and accuracy 72% (30 false-positive and 3 false-negative). Inclusion of uninterpretable segments had variable effect on sensitivity and specificity, depending on whether they are considered as significant or non-significant stenosis.ConclusionsIn patients with very extensive CAC (>1000 Agatston units), CCTA retained a negative predictive value ​> ​90% to identify lack of significant stenosis on a per-vessel and per-patient level, but frequently overestimated stenosis.     

64排螺旋CT冠脉成像在冠心病诊断中的应用

目的 评价64排螺旋CT冠状动脉(冠脉)成像(CTA)在冠心病诊断中的应用价值.方法 以选择性冠脉造影(SCA)结果为金标准,采用64排螺旋CT对68例疑诊冠心病患者的冠脉主干及主要分支272节段进行重建和分析,评价其诊断冠心病的灵敏度和特异度.结果 CTA能够清晰显示冠脉主干及其分支狭窄、钙化、开口起源异常及桥血管病变,CTA发现钙化病变52节段,SCA仅发现钙化病变35节段.CTA诊断冠脉病变的灵敏度96.33%,特异度98.16%,阳性预测值97.22%,阴性预测值97.56%.其中对左主干、左前降支病变及＞75%的病变灵敏度最高,分别达到100%和94.4%.结论 CTA对冠脉狭窄病变、桥血管、开口畸形、支架管腔均显影良好,对冠心病诊断有较高的准确性,对钙化病变诊断率优于冠脉造影,可以作为冠心病高危人群无创性筛选检查及冠脉支架术后随访手段.     

无常规心率控制下64排螺旋CT诊断冠状动脉狭窄的应用价值

目的 以有创性冠状动脉造影(ICA)为"金标准",评估无常规心率控制下64排螺旋CT冠状动脉成像(CTA)诊断冠状动脉狭窄的可靠性.资料与方法 35例患者先后行64排螺旋CT冠状动脉CTA和ICA,CTA扫描前所有患者均未常规控制心率.在未获知ICA结果的情况下,两位观察者独立对CTA结果作出评价.以冠状动脉管腔狭窄程度≥50%作为确定冠状动脉狭窄存在的标准.结果 ICA共显示75处冠状动脉管腔狭窄.64排螺旋CT冠状动脉CTA诊断冠状动脉狭窄的敏感度、特异度、阳性预测值及阴性预测值分别为:97.3%(73/75), 98.9%(468/473),93.6%(73/78)和99.6%(468/470).结论 在无常规心率控制条件下,64排螺旋CT冠状动脉CTA诊断冠状动脉狭窄仍具有很高的准确性.     

64层螺旋CT冠状动脉成像与冠状动脉造影的对比研究

目的评价64层螺旋CT冠状动脉成像诊断冠状动脉狭窄的准确性。方法 50例患者先后进行64层螺旋CT冠状动脉成像和冠状动脉造影检查,以冠状动脉造影为诊断冠状动脉疾病的"金标准",比较CT冠状动脉成像的符合率,评价64层螺旋CT冠状动脉成像诊断冠心病的准确性。结果 64层螺旋CT冠状动脉成像评价冠状动脉狭窄程度大于或等于50%的敏感性为98.6%,诊断狭窄程度小于50%的敏感性为87.0%,诊断冠状动脉狭窄的特异性为92.5%,阴性预测值为97.7%。结论 64层螺旋CT冠脉成像诊断冠状动脉狭窄有很高的准确率。     

基于人工智能的冠状动脉CT血管成像检测阻塞性冠状动脉狭窄效能的研究

目的 以有创冠状动脉造影（ICA）为参考标准,探讨人工智能(AI)辅助的冠状动脉CT血管成像（CCTA）诊断阻塞性冠状动脉狭窄的效能。 方法 回顾性收集行CCTA检查并于3个月内行ICA检查的50例疑患冠状动脉疾病（CAD）的病人,男34例,女16例,平均年龄（61.8±8.5）岁。AI软件、不同年资医师（低/中/高年资）及AI+不同年资医师分别对入组病人CCTA影像进行后处理并解读。将ICA和CCTA上冠状动脉管腔狭窄≥50%定义为阻塞性冠状动脉狭窄。采用Agatston积分法测量病人的钙化积分值,并将病人分为低钙化组（钙化积分<100）和高钙化组（钙化积分≥100）。采用独立样本t检验对AI、医师及AI+医师的图像后处理和解读时间进行两两比较。以ICA为参考标准,分析AI在不同研究水平和高/低钙化组的诊断价值,并比较AI、不同年资医师和AI+不同年资医师的诊断敏感度、特异度、阳性预测值、阴性预测值、准确度及受试者操作特征（ROC）曲线下面积（AUC）。采用Pearson卡方检验或Fisher精确概率检验比较组间差异,采用DeLong检验比较AUC。 结果 50例病人共分析195支血管424个节段。AI和AI+医师的平均后处理和解读时间均低于单独医师诊断的时间（均P<0.05）,AI的时间较低/中/高年资医师分别减少了80%、76.8%和75%;AI+低/中/高年资医师较单独医师分别减少了67%、64%、57.9%。在病人、血管及节段水平,AI诊断阻塞性冠状动脉狭窄的敏感度分别为93.7%、83.1%、67.7%,特异度为50.0%、89.0%、91.0%,准确度为92%、86.7%、85.6%,阳性预测值为97.8%、83.1%、69.8%,阴性预测值为25%、89.0%、90.2%,AUC为0.87、0.89、0.83;在血管及节段水平,AI对低钙化组的特异度高于高钙化组（均P<0.05）。在血管水平,AI诊断的AUC值均低于中/高年资医师（均P<0.05）;其余研究水平,AI与其他不同年资医师诊断的AUC值差异均无统计学意义（均P>0.05）。3种研究水平下,AI+低/中/高年资医师诊断的AUC值与单独不同年资医师诊断的AUC值差异均无统计学意义（均P>0.05）。 结论 AI辅助的CCTA诊断阻塞性冠状动脉狭窄具有较好的诊断效能,且明显缩短后处理时间,可能成为临床医师诊断阻塞性冠状动脉狭窄的有效辅助工具。     

CT-Angiographie der Koronarien mit prospektivem EKG-Triggering

Background

The purpose of this study was to evaluate the diagnostic performance of coronary CT angiography (coronary CTA) using prospective ECG triggering (PT) for the detection of significant coronary artery stenosis compared to invasive coronary angiography (ICA).

Methods

A total of 20 patients underwent coronary CTA with PT using a 128-slice CT scanner (Definition? AS+, Siemens) and ICA. All coronary CTA studies were evaluated for significant coronary artery stenoses (≥50% luminal narrowing) by 2 observers in consensus using the AHA-15-segment model. Findings in CTA were compared to those in ICA.

Results

Coronary CTA using PT had 88% sensitivity in comparison to 100% with ICA, 95% to 88% specificity, 80% to 92% positive predictive value and 97% to 100% negative predictive value for diagnosing significant coronary artery stenosis on per segment per patient analysis, respectively. Mean effective radiation dose-equivalent of CTA was 2.6±1 mSv.

Conclusion

Coronary CTA using PT enables non-invasive diagnosis of significant coronary artery stenosis with high diagnostic accuracy in comparison to ICA and is associated with comparably low radiation exposure.     

Noninvasive coronary angiography using 64-detector-row computed tomography in patients with a low to moderate pretest probability of significant coronary artery disease

PURPOSE: To evaluate the value of 64-detector-row computed tomography for ruling out high-grade coronary stenoses in patients with a low to moderate pretest probability of significant coronary artery disease. MATERIAL AND METHODS: The study included 61 patients with a suspicion of coronary artery disease on the basis of atypical angina or ambiguous findings in noninvasive stress testing and a class II indication for invasive coronary angiography (ICA). All patients were examined by 64-detector-row computed tomography angiography (CTA) and ICA. On a coronary segmental level, the presence of significant (> or = 50% diameter) stenoses was examined. RESULTS: In a total of 915 segments, CTA detected 62 significant stenoses. Thirty-four significant stenoses were confirmed by ICA, whereas 28 stenoses could not be confirmed by ICA. Twenty-two of them showed wall irregularities on ICA, and six were angiographically normal. Accordingly, on a coronary segmental basis, 28 false-positive and 0 false-negative findings resulted in a sensitivity of 100%, a specificity of 96.8%, a positive predictive value of 54.8%, and a negative predictive value of 100%. The diagnostic accuracy was 96.9%. CONCLUSION: Sixty-four-detector-row computed tomography reliably detects significant coronary stenoses in patients with suspected coronary artery disease and appears to be helpful in the selection of patients who need to undergo ICA. Calcified and non-calcified plaques are detected. Grading of stenoses in areas with calcification is difficult. Frequently, stenosis severity is overestimated by 64-detector-row computed tomography.