钙化积分、CTCA以及两者联合对冠状动脉狭窄的诊断价值

目的:探讨冠状动脉钙化积分(CS)、CT冠状动脉成像(CTCA)以及两者联合对诊断冠状动脉狭窄病变的价值.方法:189例患者均行冠状动脉钙化积分扫描、CT冠状动脉成像以及传统冠状动脉造影(CAG)检查.计算CS、CT-CA以及两者联合诊断冠状动脉病变的符合率,并记录有效X线剂量.结果:189例患者中临床诊断为冠心病156例(82.5％),经冠状动脉造影检测出至少有1支冠状动脉狭窄≥50％.采用钙化积分250分作为诊断阈值,检测冠状动脉狭窄≥50％的敏感度和特异度分别为42.9％(67/156)和96.9％(32/33).CTCA检测冠状动脉狭窄≥50％的敏感度和特异度分别为98.1％(153/156)和72.7％(24/33).CS和CTCA联合时,检测冠状动脉狭窄≥50％的敏感度和特异度分别为96.2％(150/156)和87.9％(29/33).结论:钙化积分对诊断冠状动脉狭窄有着很高的特异度;CTCA对诊断冠状动脉狭窄有着很高的敏感度;CTCA联合钙化积分扫描可提高冠状动脉狭窄的诊断符合率.     

冠状动脉显著性狭窄CTCA、MRCA及CAG一致性对照研究

目的 评价CT冠状动脉造影(CTCA)、MR冠状动脉造影(MRCA)及冠状动脉血管造影(CAG)显示冠状动脉显著性狭窄的一致性.资料与方法 搜集同期行CTCA、MRCA及CAG检查的患者30例,参照冠状动脉狭窄程度的评判标准,将冠状动脉显著性狭窄分为轻度狭窄(50%～75%)和重度狭窄(76%～100%),以CAG结果为标准,采用Kappa统计学方法,对比分析CTCA、MRCA显示冠状动脉显著性狭窄的一致性.结果 CTCA/MRCA评价冠状动脉轻度狭窄的敏感性、特异性及准确性分别为94.73%/85.40%、93.73%/86.14%及90.80%/84.52%,二者之间的一致性为88.86%(Kappa=0.163,P<0.05);评价重度狭窄的敏感性、特异性及准确性分别为95.87%/84.85%、94.54%/83.33%及90.46%/82.75%,二者之间的一致性为85.24%(Kappa=0.185,P<0.05).结论 对冠状动脉显著性狭窄的评价,CTCA优于MRCA,应作为首选方法,但二者有一定的互补作用.     

320层容积CT无心率(律)控制的冠状动脉血管成像在冠心病高危人群中的初步应用

目的 探讨在无心率(律)控制条件下,320层容积CT冠状动脉血管成像(VCTA)诊断冠心病高危人群冠状动脉狭窄的准确性.方法 对30例有冠心病高危因素的患者,以冠状动脉导管造影(ICA)为金标准,评价VCTA诊断冠状动脉节段狭窄率≥50%的敏感度、特异度、阳性预测值(PPV)、阴性预测值(NPV)及Youden指数;同时采用卡方检验分析心率快慢及钙化程度对2种检查方法诊断一致率的影响.结果 30例患者平均心率(73.7±15.4)次/min(bpm),420个可分析节段的平均Agatston钙化积分中位数为45.6分(OR=181).心率＜70和≥70 bpm分别显示242和169段,诊断一致率差异无统计学意义(P＞0.05);Agatston钙化积分≥100分的图像质量和诊断一致率低于Agatston钙化积分＜100分的节段,但VCTA与ICA结果仍具有良好吻合性(P＞0.05).结论 在无心率(律)控制情况下,VCTA对冠心病高危人群的冠状动脉狭窄诊断具有很高的准确性.     

静息状态下CT冠状动脉造影联合心肌首过灌注成像诊断冠心病的临床可行性与准确性分析

目的探讨静息状态下CT冠状动脉造影(CT coronary angiography,CTCA)与心肌首过灌注成像联合诊断冠心病的临床可行性,并对其准确性进行分析。方法选取在我院接受诊断或治疗的可疑或确定冠心病患者52例,行CTCA和冠状动脉造影(cornary angioiography,CAG)检查,并以CTCA的数据进行心肌首过灌注成像分析,以冠脉造影及负荷/静息心肌灌注显像为诊断金标准,比较CTCA和CTCA+心肌首过灌注成像诊断冠状动脉狭窄及心肌灌注缺损诊断的准确性。结果 CAG显示144支血管中,中、重度狭窄55支。CTCA显示中、重度狭窄56支,CTCA结合心肌首过灌注成像显示冠脉狭窄阳性54支;参照CAG结果,CTCA对冠状动脉狭窄诊断的敏感性为78.2%,特异性85.4%,阳性预测值76.8%,阴性预测值86.4%,准确率82.6%;参照CAG结果,CTCA联合心肌首过灌注成像对冠状动脉狭窄诊断的敏感性为92.7%,特异性96.6%,阳性预测值为94.4%,阴性预测值为95.6%,准确率为95.1%,CTCA与CTCA结合心肌首过灌注成像各诊断指标之间差异有统计学显著性(P0.05)。以负荷/静息心肌灌注显像为参考标准,CTCA+心肌首过灌注成像诊断心肌灌注缺损的灵敏度、特异度、阳性预测值、阴性预测值及准确度分别为88.41%、93.01%、73.49%,97.34%及92.19%。结论静息状态下,CTCA+心肌首过灌注成像可以提供关于冠脉解剖学和功能学的信息,临床应用价值较高,且对冠心病的诊断准确性较高,值得临床进一步推广使用。     

多层螺旋CT评价冠状动脉狭窄和钙化的应用价值

目的 研究多层螺旋CT诊断冠状动脉狭窄的准确性以及冠状动脉狭窄与钙化的关系.方法 对52例临床可疑冠心病患者(男34例,年龄61岁±12岁)进行多层螺旋CT冠状动脉造影和常规冠状动脉造影.用CT平扫图像计算冠状动脉钙化积分.用CT增强扫描图像评价冠状动脉超过50%的狭窄,将结果 与常规冠状动脉造影作对照.分析冠状动脉狭窄和钙化的相关关系.结果 常规冠状动脉造影发现208个冠状动脉分支中61个超过50%狭窄.CT血管造影诊断冠状动脉超过50%狭窄的敏感性为93.4%,特异性为91.8%.冠状动脉狭窄严重程度与钙化程度的spearman相关系数为r=0.783,P<0.01.结论 多层螺旋CT对诊断冠状动脉狭窄有较高的敏感性和特异性.冠状动脉狭窄与钙化有显著相关关系.     

双源CT自适应前瞻性心电门控冠状动脉造影:与传统冠状动脉造影对照

目的 评价双源CT(DSCT)自适应前瞻性心电门控CT冠状动脉成像(CTCA)对冠状动脉病变诊断的准确性和可行性.资料与方法选取同期行自适应前瞻性心电门控CTCA(扫描前心率低于75次/min)和传统冠状动脉造影(CAG)的30例连续患者作为研究对象.另选取同期行回顾性心电门控CTCA和CAG的45例连续患者作为对照.由两名CT医师和两名造影医师分别对CTCA和CAG图像进行评估.记录CTCA的图像质量和X线剂量.比较自适应前瞻性和回顾性心电门控CTCA的诊断准确性、X线剂量和图像质量.结果 对患者冠状动脉病变的诊断,自适应前瞻性和回顾性心电门控CTCA的差异无统计学意义,其敏感性分别为100%、97.4%(P=0.86),特异性分别为66.7%、100%(P=0.65);对分支冠状动脉病变的诊断,两者差异也无统计学意义,其敏感性分别为95.9%、91.1%(P=0.46),特异性分别为97.2%、97.0%(P=0.85);对节段冠状动脉病变的诊断,两者差异同样无统计学意义,其敏感性分别为90.5%、91.2%(P=0.92),特异性分别为98.4%、99.3%(P=0.35).自适应前瞻性心电门控CTCA的冠状动脉图像质量与回顾性心电门控CTCA类似(3.3±0.5与3.2±0.3;P:0.23).与回顾性心电门控CTCA比较,自适应前瞻性心电门控CTCA能降低71%的X线剂量[(3.1±1.3)mSv与(10.8±4.6)mSv,P＜0.01].结论 在心率低于75次/min、心律稳定的情况下,DSCT自适应前瞻性心电门控CTCA能获得与DSCT回顾性心电门控CTCA相同的诊断准确性,图像质量也无差别,而X线剂量却大大降低.     

低辐射量CT冠状动脉造影联合斑块钙化积分对评估冠状动脉狭窄的临床价值

目的 分析低辐射量CT冠状动脉造影(coronary angiography,CTCA)联合斑块钙化积分对评估冠状动脉狭窄的临床价值.方法 采取前瞻性研究,选取行低辐射量CT℃A检查的75例患者作为研究对象,其中男患占65.33％ (49/75),女患占34.67％ (26/75),均采取低辐射量CTCA扫描,在低辐射量CTCA图像中评估斑块钙化积分,并以侵入性冠状动脉造影结果为参考标准,综合评估冠状动脉狭窄情况,分为冠状动脉明显狭窄组和冠状动脉无明显狭窄组,对比两组患者的斑块钙化积分,分析低辐射量CTCA、斑块钙化积分及两者联合对冠状动脉狭窄的诊断准确率.结果 冠状动脉明显狭窄组的斑块钙化积分503.2±557.4,高于冠状动脉无明显狭窄组的42.6±79.6,差异显著(P =0.002,＜0.01);低辐射量CTCA评估冠状动脉狭窄的灵敏度、特异度、诊断符合率分别为96.2％、78.26％、90.67％,斑块钙化积分评估冠状动脉狭窄的灵敏度、特异度、诊断符合率分别为85.19％、100.0％、89.47％,两者联合评估冠状动脉狭窄的灵敏度、特异度、诊断符合率分别为96.15％、100.0％、97.33％.结论 在冠状动脉狭窄的评估方法选择上,低辐射量CTCA、斑块钙化积分分别具有很高的敏感度、特异度,两者联合可进一步提高对冠状动脉狭窄的评估准确率,不额外增加辐射剂量、延长扫描时间,值得临床借鉴应用.     

电子束CT血管造影评价冠状动脉狭窄

目的:探讨电子束CT(EBT)血管造影评价冠状动脉狭窄的价值.材料和方法:分析56例经EBT血管造影和常规冠状动脉造影(CAG)检查的资料,将冠状动脉各支分成13个节段与相应CAG结果逐一对照,并进行统计学分析.结果:679个≥2mm的冠状动脉节段中,EBT可评价562个,无法评价117个.EBT对各支冠状动脉的评价准确性依次为左主干、前降支和右冠;对各节段的评价以近段的敏感性、特异性和阴性预测值最高;对不同程度狭窄的评价以＞75%狭窄的诊断最为可靠.此外对正常冠状动脉的诊断准确性也较高,为88.5%.结论:EBT血管造影对评价冠状动脉近段狭窄、重度狭窄和正常血管有很高的价值,可作为CAG术前筛选的常规无创性检查方法.     

64层CTA诊断房颤患者冠状动脉狭窄准确性的临床研究

目的:与CAG对照分析来评价64层螺旋CT冠状动脉成像在房颤患者中诊断有血流动力学意义的冠状动脉狭窄的准确性.方法:58例房颤患者行64层螺旋CT冠状动脉成像,扫描前均未服用倍它乐克.血管图像质量分为好、中等和差.以CAG作为参考标准,分别基于血管节段和患者水平来分析MDCTCA诊断有血流动力学意义的冠状动脉狭窄的敏感性、特异性、阳性预测价值和阴性预测价值.诊断价值的评价首先仅限于图像质量达到诊断要求的血管节段和患者,进一步的分析中将图像质量不能诊断的血管节段和患者均作为阳性来处理.结果:58例患者有645段(96.55%)图像质量为中等以上,诊断有血流动力学意义的敏感性、特异性、阳性预测价值和阴性预测价值分别是86.21%(25/29)、99.35%(612/616)、86.21%(25/29)和99.35%(612/616).将23段图像质量没有达到诊断要求的血管均作为阳性后,CTCA诊断有血流动力学意义的血管狭窄的总体阳性预测价值为48.08%(25/52),特异性为95.77%(612/639).基于患者总体图像质量的分析,58例患者中有47例(81.03%)图像质量为中等W_h,CTCA诊断有血流动力学意义的敏感性、特异性、阳性预测价值和阴性预测价值分别是87.50%(7/8)、97.44%(38/39)、87.50%(7/8)f97.44%(38/39).将11例图像质量没有达到诊断要求的血管均作为阳性后,CTCA诊断有血流动力学意义的血管狭窄的敏感性、特异性、阳性预测价值和阴性预测价值分别是90.00%(9/10)、79.17%(38/48)、47.37%(9/19)和97.44%(38/39).结论:64CTCA在房颤患者中诊断有血流动力学意义的冠状动脉狭窄具有较好的阴性预测价值,但需要进一步提高图像质量来提高诊断血管狭窄的准确性.     

应用超声心动图左室壁运动异常节段推测冠心病相关狭窄血管--与冠脉造影对比研究

目的:探讨二维心超(2DE)对冠心病的诊断价值及对相关狭窄血管推测的准确性。材料和方法:200例临床初步诊断为冠心病的患者同期进行2DE及导管法冠脉造影(CAG)检查(2DE在先,CAG在后),以CAG为标准,统计分析根据节段性室壁运动异常推测冠脉相关狭窄血管的准确性。结果:对狭窄冠脉具体血管数的检出两种方法比较,LAD、LCX、多支病变两者无明显差异(P>0.05),以CAG为标准,2DE推测冠心病相关狭窄血管的特异性较高,敏感性较低,约登指数<0.5;当冠状动脉的某一支狭窄≥90%或次全闭塞时,2DE推测冠心病的准确性明显提高,对LAD、LCX、RCA的判断敏感性均>70%,特异性均>85%,约登指数均>0.6。结论:2DE是一种简便、无创、良好辅助冠脉造影的方法,当血管狭窄≥90%或次全闭塞时准确性较高,当血管狭窄<90%时准确性欠佳。     

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-slice computed tomography coronary angiography: diagnostic accuracy in the real world

PURPOSE: This study was done to evaluate the diagnostic accuracy of 64-slice computed tomography coronary angiography (CTCA) for the detection of significant coronary artery stenosis in the real clinical world. MATERIALS AND METHOD: From the CTCA database of our institution, we enrolled 145 patients (92 men, 52 women, mean age 63.4 +/- 10.2 years) with suspected coronary artery disease. All patients presented with atypical or typical chest pain and underwent CTCA and conventional coronary angiography (CA). For the CTCA scan (Sensation 64, Siemens, Germany), we administered an IV bolus of 100 ml of iodinated contrast material (Iomeprol 400 mgI/ml, Bracco, Italy). The CTCA and CA reports used to evaluate diagnostic accuracy adopted > or =50% and > or =70%, respectively, as thresholds for significant stenosis. RESULT: Eleven patients were excluded from the analysis because of the nondiagnostic quality of CTCA. The prevalence of disease demonstrated at CA was 63% (84/134). Sensitivity, specificity and positive and negative predictive values for CTCA on a per-segment, per-vessel, and per-patient basis were 75.6%, 85.1%, 97.6%; 86.9%, 81.8%, 58.0%; 48.2%, 68.1%, 79.6%; and 95.7%, 92.3%, 93.5%, respectively. Only two out of 134 eligible patients were false negative. Heart rate did not significantly influence diagnostic accuracy, whereas the absence or minimal presence of coronary calcification improved diagnostic accuracy. The positive and negative likelihood ratios at the per-patient level were 2.32 and 0.041, respectively. CONCLUSION: CTCA in the real clinical world shows a diagnostic performance lower than reported in previous validation studies. The excellent negative predictive value and negative likelihood ratio make CTCA a noninvasive gold standard for exclusion of significant coronary artery disease.     

双源CT冠状动脉成像在飞行人员冠心病诊断中的价值

目的 探讨双源CT冠状动脉成像在飞行人员冠心病诊断中的临床应用价值.方法对10名临床怀疑冠心病的飞行人员患者行双源CT冠状动脉成像（computed tomography coronary angiography,CTCA）检查和常规X线冠状动脉血管造影（conventional coronary angiography,CCA）检查,以CCA为金标准比较分析CTCA诊断冠状动脉狭窄的敏感性、特异性及准确性.结果 10例飞行人员患者均成功完成了双源CTCA与CCA 检查,双源CTCA图像优良率为96.3%.CTCA发现不同程度冠状动脉狭窄和斑块形成7例,其中2例同时存在前降支心肌桥;冠状动脉-肺动脉瘘1例;冠状动脉正常2例.7例患者的CTCA图像上15个冠状动脉节段有不同程度狭窄,以CCA为金标准,双源CTCA诊断冠状动脉有狭窄的敏感性、特异性及准确率分别为100.0%、98.2%、98.4%;诊断冠状动脉中度及中度以上狭窄的敏感性、特异性及准确率分别为80.0%、99.2%、98.4%.双源CTCA与CCA显示冠状动脉节段病变的能力无统计学差异（χ2=0.50,P=0.4795）.结论 双源CTCA作为一种无创检查方法,能够准确地评估飞行人员冠状动脉狭窄程度和冠状动脉管壁斑块情况,并能显示冠状动脉先天变异等,对于安全可靠地诊断飞行人员冠心病具有较高的应用价值.     

Diagnostic accuracy of 64-slice computed tomography coronary angiography in a large population of patients without revascularisation: registry data on the impact of calcium score

Purpose

This study evaluated the diagnostic accuracy of computed tomography coronary angiography (CTCA) for detecting significant coronary artery stenosis (??50% lumen reduction) at different coronary calcium score (CACS) values with conventional coronary angiography (CAG) as the reference standard.

Material and methods

A total of 1,500 patients (928 men, mean age 58.2??12.5 years) in sinus rhythm who underwent CTCA (64-slice technology) and CAG were enrolled. Diagnostic accuracy and likelihood ratios (LR) of CTCA were evaluated against CAG for the total population and in different CACS classes (0; 1?C10; 11?C100; 101?C400; 401?C1,000; >1,000).

Results

The prevalence of obstructive disease was 51% (23.5% single vessel; 27.5% multivessel; progressive increase from 17.9% to 94% through the CACS classes). In the per-patient analysis, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of CTCA were 99%, 92%, 94% and 99%, respectively. Per-patient analysis showed a worse PPV of CTCA (76?C77%) in classes with low CACS (1?C10/11?C100). Per-patient LR were higher in classes with extreme CACS values (0 = LR+ 18.3 and LR? = 0.0; c1,000 = LR+ 17.0 and LR? = 0.0) with values always >7 for LR+ and <0.033 for LR? for all CACS classes.

Conclusions

CTCA is a reliable diagnostic modality, with high sensitivity and NPV regardless of CACS.     

Coronary calcium score as gatekeeper for 64-slice computed tomography coronary angiography in patients with chest pain: per-segment and per-patient analysis

We sought to investigate the performance of 64-slice CT in symptomatic patients with different coronary calcium scores. Two hundred patients undergoing 64-slice CT coronary angiography for suspected coronary artery disease were enrolled into five groups based on Agatston calcium score using the Mayo Clinic risk stratification: group 1: score 0, group 2: score 1–10, group 3: score 11–100, group 4: score 101–400, and group 5: score > 401. Diagnostic accuracy for the detection of significant (≥50% lumen reduction) coronary artery stenosis was assessed on a per-segment and per-patient base using quantitative coronary angiography as the gold standard. For groups 1 through 5, sensitivity was 97, 96, 91, 90, 92%, and specificity was 99, 98, 96, 88, 90%, respectively, on a per-segment basis. On a per-patient basis, the best diagnostic performance was obtained in group 1 (sensitivity 100% and specificity 100%) and group 5 (sensitivity 95% and specificity 100%). Progressively higher coronary calcium levels affect diagnostic accuracy of CT coronary angiography, decreasing sensitivity and specificity on a per-segment base. On a per-patient base, the best results in terms of diagnostic accuracy were obtained in the populations with very low and very high cardiovascular risk. Authors have no financial conflict of interest. Neither this paper nor any of its content has not been submitted to other journals.     

Significant coronary artery stenosis: comparison on per-patient and per-vessel or per-segment basis at 64-section CT angiography

PURPOSE: To prospectively evaluate the accuracy of 64-section computed tomographic (CT) coronary angiography for assessing significant stenosis on a global and segmental level, by using conventional coronary artery angiography as the reference standard. MATERIALS AND METHODS: This study was HIPAA compliant and had local institutional review board approval. Patients gave informed consent. Patients suspected of having coronary artery disease (CAD) underwent both conventional coronary catheter angiography and contrast material-enhanced retrospectively electrocardiographically gated 64-section multi-detector row CT of the coronary arteries. Two experienced observers analyzed all CT scans for signs of CAD (stenosis of 0%, or=50%) stenosis in CAD with an accuracy of 89%. On a per-segment and per-vessel basis, diagnostic accuracy is still impaired, primarily by limited spatial resolution.     

Diagnostic accuracy of 64-slice computed tomography coronary angiography in a large population of patients without revascularisation: registry data on the comparison between male and female population

Purpose

This study was undertaken to evaluate the diagnostic accuracy of computed tomography coronary angiography (CTCA) for detecting significant coronary artery stenosis (??50% lumen reduction) compared with conventional coronary angiography (CAG) in a male and female population.

Material and methods

A total of 1,372 patients (882 men, 490 women; mean age 59.3 ± 11.9 years) in sinus rhythm imaged with CTCA (64-slice technology) and CAG were enrolled. Diagnostic accuracy and likelihood ratios (LR+ and LR?) of CTCA were assessed against CAG for the male and female populations.

Results

The prevalence of obstructive disease was 53% (men 58%; women 43%). CAG demonstrated the absence of significant coronary artery disease (CAD) in 47% (men 42%; women 56%), single-vessel disease in 25% (men 36%; women 22%) and multivessel disease in 29% (men 32%; women 23%) of patients. In the per-patient analysis, sensitivity, specificity and positive (PPV) and negative (NPV) predictive values of CTCA were 99% (men 98%; women 100%), 92% (men 92%; women 92%), 94% (men 95%; women 90%) and 99% (men 98%; women 100%), respectively. The per-patient likelihood ratios (LR) in the total population (LR+=12.4 and LR?=0.011), the male (LR+=12.9 and LR?=0.016) and female (LR =11.9 and LR?=0) populations were very good. We observed no significant differences in diagnostic accuracy between male and female populations.

Conclusions

CTCA is a reliable diagnostic modality with high sensitivity and NPV in the female population.     

Noninvasive coronary angiography using 64-slice spiral computed tomography in an unselected patient collective: effect of heart rate, heart rate variability and coronary calcifications on image quality and diagnostic accuracy

OBJECTIVE: The aim of this study was to assess the impact of heart rate, heart rate variability and calcification on image quality and diagnostic accuracy in an unselected patient collective. SUBJECTS AND METHODS: One hundred and two consecutive patients with known or suspected coronary artery disease underwent both 64-MSCT and invasive coronary angiography. Image quality (IQ) was assessed by independent observers using a 4-point scale from excellent (1) to non-diagnostic (4). Accuracy of MSCT regarding detection or exclusion of significant stenosis (>50%) was evaluated on a per segment basis in a modified AHA 13-segment model. Effects of heart rate, heart rate variability, calcification and body mass index (BMI) on IQ and accuracy were evaluated by multivariate regression. IQ and accuracy were further analysed in subgroups of significant predictor variables and simple regression performed to calculate thresholds for adequate IQ. RESULTS: Mean heart rate was 68.2+/-13.3 bpm, mean heart rate variability 11.5+/-16.0 beats per CT-examination (bpct) and median Agatston score 226.5. Average IQ score was 2+/-0.6 whilst diagnostic quality was obtained in 89% of segments. Overall sensitivity, specificity, PPV or NPV was 91.2%, 99.2%, 95.3% or 98.3%. According to multivariate regression, overall IQ was significantly related to heart rate and calcification (P=0.0038; P<0.0001). The effect of heart rate variability was limited to IQ of RCA segments (P=0.018); BMI was not related to IQ (P=0.52). Calcification was the only predictor variable with significant effect on the number of non-diagnostic segments (P<0.0001). In a multivariate regression, calcification was also the single factor with impact on diagnostic accuracy (P=0.0049). CONCLUSION: Whilst heart rate, heart rate variability and calcification all show an inverse correlation to IQ, severe calcium burden remains the single factor with translation of such effect into decrease of diagnostic accuracy.     

MSCT冠状动脉造影的临床应用

目的: 评价多层螺旋CT(MSCT)冠状动脉造影效果及其诊断冠状动脉狭窄的价值.材料和方法:65例临床疑诊冠心病患者作MSCT扫描,所有数据获得在一次屏气中完成.利用心电门控技术,将所得原始图像进行重建,分别对左主干(LMA)、左前降支(LAD)、回旋支(LCA)和右冠状动脉(RCA)及其分支的重建图像进行影像学评价;其中45例同时作常规冠状动脉造影(CAG),以造影结果为金指标,将两种方法所得结果进行对比,了解MSCT冠状动脉造影诊断冠脉狭窄的敏感性和特异性.结果:MSCT冠脉钙化积分诊断冠心病的敏感性79.6%,特异性84.9%;65例共260支血管经MSCT成像,228支(87.7%)可用于影像学评价;各节段冠状动脉重建图像,左主干和前降支近中段显示率最高;CAG发现狭窄49支, MSCT发现狭窄44支.MSCT对冠状动脉狭窄诊断的敏感性83.7%,特异性97.7%.结论: 在控制心率的情况下,MSCT冠状动脉造影可作为诊断冠状动脉狭窄的一种无创筛选检查方法.