Non-invasive detection of significant coronary artery disease with multi-section computed tomography angiography in patients with suspected coronary artery disease

AIM: The objective of this prospective study was to compare the accuracy of multi-section computed tomography (MSCT) coronary angiography with invasive selective coronary angiography in the detection of significant coronary stenosis (> or =50% lumen diameter narrowing). METHODS: Thirty consecutive patients (mean age 59+/-10 years) with suspected coronary artery disease underwent both invasive coronary angiography and MSCT using a 40-section multidetector row machine with temporal resolution of 53ms. Reconstruction images were performed in eight phases of the cardiac cycle. Images of MSCT and invasive coronary angiography were analysed using the 16-segment model of the American Heart Association. RESULTS: A total of 480 segments from 30 patients were evaluated. Coronary segments distal to a vessel occlusion and segments with coronary stent were not considered for analysis (20 segments in total). Ninety-four (20.4%) segments showed significant (> or =50%) stenosis by invasive coronary angiogram. The accuracy of coronary MSCT was computed on a per segment basis. Average sensitivity, specificity, positive predictive value, and negative predictive value of MSCT were 99, 98, 94, and 99%, respectively. CONCLUSION: This study demonstrated that MSCT is as reliable as coronary angiography at detecting significant obstructive coronary artery disease. In selected groups of patients, it may replace the more invasive and potentially more dangerous conventional coronary angiography.     

Evaluation of coronary bypass graft occlusion and stenosis with 64-detector-row computed tomography angiography

Background: A noninvasive imaging modality is desirable for the evaluation of coronary bypass graft stenosis and occlusion.

Purpose: To prospectively evaluate the effectiveness of 64-detector-row computed tomography (DCT) for the assessment of coronary bypass grafts.

Material and Methods: Forty-two patients (35 male, seven female, mean age 66.3 years) with 103 bypass grafts (32 arterial, 71 venous) were examined with 64-DCT. The evaluations were done by two radiologists blinded to the results of quantitative coronary angiography (QCA), used as the reference standard.

Results: All of the 26 occluded grafts, nine of the 10 stenosed grafts, and 66 of the 67 patent grafts were correctly diagnosed with 64-DCT angiography. The sensitivity, specificity, and positive and negative predictive values for 64-DCT in detecting graft stenosis were 90%, 99%, 90%, and 99%, respectively. For graft occlusion, all were 100%. No statistically significant difference was found between 64-DCT and QCA for the evaluation of bypass grafts. Intermodality and interobserver agreement were excellent.

Conclusion: 64-DCT angiography is a reliable, noninvasive diagnostic method for the assessment of coronary bypass grafts. It can be considered as a useful tool for follow-up purposes and may function as a gatekeeper before invasive procedures.     

In-vitro evaluation of coronary stents and 64-detector-row computed tomography using a newly developed model of coronary artery stenosis

BACKGROUND: Stent implantation is the predominant therapy for non-surgical myocardial revascularization in patients with coronary artery disease. However, despite substantial advances in multidetector computed tomography (MDCT) coronary imaging, a reliable detection of coronary in-stent restenosis is currently not possible. PURPOSE: To examine the ability of 64-detector-row CT to detect and to grade in-stent stenosis in coronary stents using a newly developed ex-vivo vessel phantom with a realistic CT density pattern, artificial stenosis, and a thorax phantom. MATERIAL AND METHODS: Four different stents (Liberté and Lunar ROX, Boston Scientific; Driver, Medtronic; Multi-Link Vision, Guidant) were examined. The stents were placed on a polymer tube with a diameter of 2.5, 3.0, 3.5, or 4.0 mm. Different degrees of stenosis (0%, 30%, 50%, 70-80%) were created inside the tube. For quantitative analysis, attenuation values were measured in the non-stenotic vessel outside the stent, in the non-stenotic vessel inside the stent, and in the stenotic area inside the stent. The grade of stenosis was visually assessed by two observers. RESULTS: All stents led to artificial reduction of attenuation, the least degree of which was found in the Liberté stent (11.3+/-10.2 HU) and the Multi-Link Vision stent (17.6+/-17.9 HU; P = 0.25). Overall, the non-stenotic vessel was correctly diagnosed in 55.5%, the low-grade stenosis in 58.3%, the intermediate stenosis in 63.8%, and the high-grade stenosis in 80.5%. In the 3.0-, 3.5-, and 4.0-mm vessels, in none of the cases was a non-stenotic or low-grade stenotic vessel misdiagnosed as intermediate or high-grade stenosis. The average deviation from the real grade of stenosis was 0.40 for the Liberté stent, 0.46 for the Lunar ROX stent, 0.45 for the Driver stent, and 0.58 for the Multi-Link Vision stent. CONCLUSION: Our ex-vivo data show that non-stenotic stents and low-grade in-stent stenosis can be reliably differentiated from intermediate and high-grade in-stent stenosis in vessels with a diameter of 3 to 4 mm. With regard to artifacts and the grading of stenoses, the Liberté stent was best suited for CT coronary angiography.     

Imaging of coronary artery anomalies using ECG-gated 64-row computed tomography angiography

Objective

To shed light on coronary artery anomalies among cardiac patients using ECG-gated 64-row MDCTA during assessment of coronary arteries.

Patients and methods

Study included 840 patients out of whom twenty-one patients have congenital coronary artery anomalies. Patients were examined using ECG gated 64-row MDCT; 80–100 ml contrast agent, followed by a 50 ml saline chaser injected at 5 ml/s, 350 ms gantry rotation time, 0.65 mm detector collimation, ECG tube current modulation and 100–120 kV. Post-processing was done on second workstation including 3D VR, MPR and CMPR images.

Results

Anomalies of the coronary arteries were diagnosed in twenty-one patients. The prevalence of congenital anomalies in this study was 2.5% and included: anomalous origin of right coronary artery in 4 cases (0.48%), anomalous origin of left circumflex artery in 3 cases (0.36%), myocardial bridging of LAD in 12 cases (1.4%) and coronary artery fistula in 2 cases (0.24%).

Conclusion

Coronary artery anomalies are not uncommon among cardiac patients. Myocardial bridging is the most common followed by anomalous origin and proximal course and lastly coronary artery fistula. 64-Row MDCTA is an excellent promising modality and should be the first non-invasive diagnostic tool to rule out such anomalies.     

Sixty-four-slice computed tomography coronary angiography compared with myocardial perfusion scintigraphy for the diagnosis of functionally significant coronary stenoses in patients with a low to intermediate likelihood of coronary artery disease

Background. Multislice computed tomography coronary angiography (CTA) was proposed as a method for investigating possible coronary artery disease (CAD) in patients who present with chest pain but with a low to intermediate likelihood of CAD. Sixty-four-channel CTA was compared prospectively with ^99mTc-tetrofosmin myocardial perfusion scintigraphy (MPS) (as the gold standard in the detection of flow-limiting stenoses) for the detection of functionally significant CAD. Methods and Results. Fifty-two consecutive symptomatic patients with a low to intermediate likelihood of coronary artery disease, and who were referred for MPS, also underwent CTA. The CTA datasets were analyzed by two experienced observers who were blinded to the MPS data, and coronary artery segments were reported as <50%, 50% to 69%, 70% to 99% stenoses, or occluded. The MPS images were similarly analyzed for inducible perfusion abnormalities, and coronary territories were identified. At the patient level, agreement between CTA and MPS for CTA lesions at ≥50% was 87% (sensitivity, 100%; specificity, 84%; positive predictive value, 50%; negative predictive value, 100%). For CTA lesions, agreement at ≥70% was 96% (sensitivity, 86%; specificity, 98%; positive predictive value, 86%; negative predictive value, 98%). Conclusions. In patients with a low to intermediate likelihood of CAD, there is good correlation between MPS and CTA for the detection of functionally significant coronary artery stenoses when CTA detects a narrowing of ≥70% severity. Computed tomography coronary angiography stenoses of 70% should be used to determine functional significance, and not 50%, as is the usual practice at present. This work was funded by an unrestricted research grant from the United Kingdom Defence Postgraduate Medical Deanery. We also thank the Royal Air Force Medical Branch for financial support.     

Coronary artery calcium score and CT angiography in asymptomatic elderly patients with high pretest probability for coronary artery disease

Purpose

To evaluate the role of coronary artery calcium scoring (CACS) and/or coronary CT angiography (CCTA) in asymptomatic elderly patients with high pretest probability for coronary artery disease (CAD).

Materials and methods

Forty-eight consecutive asymptomatic elderly (>65 years) subjects who had a high pretest probability and underwent CACS/CCTA were included. Each CCTA was evaluated for adequacy for assessment of coronary stenosis. Significant stenosis (>50 % diameter narrowing) was assessed on evaluable CT images and by invasive catheter angiography (ICA).

Results

All subjects were men with mean CACS of 880 ± 1779. Among those with low (0–99), intermediate (100–399), and high (400–999) CACS, ICA-verified significant stenosis was present in 8 % (1/13), 23 % (2/13), and 67 % (8/12), respectively. Among those with very high CACS (≥1000) (n = 10), 90 % of CCTAs were not evaluable for stenosis.

Conclusion

In asymptomatic elderly subjects with high pretest probability, CACS followed by CCTA may be considered for those with intermediate to high CACS.

     

64层螺旋CT冠状动脉血管成像与冠脉造影结果对照研究

目的:评价多层螺旋CT(MSCT)冠状动脉血管成像方法显示管腔≥50%狭窄的准确性,分析改善成像质量的方法.方法:对72例临床诊断或可疑冠心病的患者在心电门控下采用64层螺旋CT进行冠状动脉血管成像.其中56例在2周内行导管法冠状动脉造影.结果:本组56例与冠状动脉造影结果相对照,冠状动脉血管成像诊断≥50%血管狭窄的敏感性为91.5%,特异性为97.5%,阳性预测值为82.3%,阴性预测值为98.9%.结论:64层螺旋CT冠状动脉血管成像具有较高的敏感性和特异性,同时具有无创和简便的特点,可以作为临床对高危人群筛查的首选方法.     

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.     

冠状动脉造影正常患者64排CT冠状动脉成像结果分析

目的 分析介入性冠状动脉造影正常患者64排CT冠状动脉成像的检查结果和影像特点.方法 对介入性冠状动脉造影结果为阴性的52例患者在1月内行64排CT冠状动脉成像检查,对阳性病例进行回顾性分析.结果 64排CT冠脉成像显示52例中,冠状动脉局限性管壁增厚29例(55.77%),管腔无狭窄23处,轻度狭窄6处,平均狭窄程度8%;弥漫性管壁增厚8例(15.38%),管腔无狭窄1例,轻度狭窄7例,平均狭窄程度为11%;单纯内膜钙化或管壁内钙化3例(5.77%),管腔未见明显狭窄.结论 64排CT冠状动脉成像更适宜作为冠心病诊断的首选影像检查方法.     

Noninvasive diagnosis of bronchial artery aneurysm using dual-source computed tomography angiography

Bronchial artery aneurysm is a rare entity, detected in less than 1% of all patients undergoing selective bronchial arteriograms. Approximately 50 cases have been reported so far. Computed tomography (CT) reports of mediastinal bronchial artery aneurysms are rare. We report a case of a bronchial artery aneurysm in an 84-year-old male patient, which had been misdiagnosed as lung cancer for 6 years.     

CT冠状动脉成像与钙化积分评价可疑冠心病患者预后

目的 探讨CT冠状动脉成像（CTCA）与钙化积分（CACS）对可疑冠心病患者预后的预测价值.方法 对150例可疑冠心病患者行前瞻性分析.所有患者均接受320排动态容积CT扫描,分析CTCA以及CACS结果,分析并对照CTCA以及CACS判断患者预后的价值.结果 85例患者CTCA发现非阻塞性冠状动脉病变（管腔狭窄≤50％）,38例患者发现阻塞性冠状动脉病变（管腔狭窄＞50％）,27例患者冠状动脉未发现异常.54例患者钙化积分在0～10之间,47例患者钙化积分在11～400之间,49例患者钙化积分大于400.冠状动脉狭窄程度、斑块的类型及钙化积分大小均为患者终点事件发生的危险因素（OR＝5.254,95％ CI=2.095-13.176,P＜0.001; OR=6.877,95％CI＝1.372-14.033,P＜0.001;OR=2.976,95％CI=1.437-6.614,P＝0.003）.冠状动脉狭窄程度、斑块类型对患者预后有显著影响（OR=3.725,95％CI=1.379-10.062,P=0.007;OR=4.283,95％CI=1.992-12.254,P＝0.002）.结论 CTCA和CACS对可疑冠心病患者预后有较高的预测价值,CTCA对患者的预后的预测价值优于CACS.     

Overestimation of pretest probability of coronary artery disease by Duke clinical score in patients undergoing coronary CT angiography in a Japanese population

BackgroundThe Duke clinical score (DCS) is commonly used to estimate the pretest probability of coronary artery disease (CAD). However, the criterion was developed in a population undergoing catheter angiography.ObjectiveTo test the hypothesis that DCS overestimates the CAD probability when applied to patients evaluated with coronary CT angiography (CCTA). A second objective is to compute an adjustment of the calculated DCS to apply to this population.MethodsThe DCS was calculated for the 3996 consecutive CCTA studies (February 2009 to April 2013) performed for symptomatic patients with no known CAD. Performance of the DCS for the detection of CAD was evaluated by the area under the receiver operating characteristic curve. Using the training cohort (n = 2789), a linear regression line between the calculated probability and the observed prevalence of CAD identified a modified DCS cutoff for a better risk categorization; this was internally validated by a separate cohort (n = 1207).ResultsThe DCS showed a good discrimination (area under the receiver operating characteristic curve = 0.71) for the detection of CAD (prevalence = 23.3%). The calibration analysis showed an overall 2.4-fold overestimation by DCS with a DCS < 23% corresponding to the low-risk category (ie, observed prevalence of CAD < 10%). There was no appropriate DCS cutoff to define high-risk category (ie, prevalence > 90%). The validation cohort showed a prevalence of 9.4% when DCS < 23% was used to define low risk.ConclusionAmong patients who underwent CCTA, DCS overestimated the pretest probability by at least 2-fold; the DCS < 23% should define the lower risk probability. The DCS poorly identifies high-risk population and thus development of new CCTA-based criteria is warranted.     

冠状动脉CT血管成像和运动平板试验对冠心病患者的诊断比较

目的:评价冠状动脉CT血管成像(CCTA)和运动平板试验(TET)对冠心病的诊断价值。方法:以常规冠状动脉造影(CAG)为诊断冠心病(冠脉狭窄≥50%)的"金标准",对同期先后行TET、CCTA和CAG 3种检查的75例疑似冠心病患者进行回顾性分析,将其TET和CCTA的结果与CAG进行比较。结果:TET和CCTA诊断冠心病的敏感度分别为45.2%和90.5%,特异度为69.7%和93.9%,阳性预测值为65.5%和95.0%,阴性预测值为50.0%和88.6%,准确率为56.0%和92.0%,P<0.01。在冠状动脉血管水平CCTA对右冠状动脉、左主干、前降支、回旋支狭窄诊断的准确率分别为86.7%、100.0%、88.0%和76.0%。冠心病患者中TET诊断阳性率与病变血管支数呈正相关(r=0.440,P=0.004);冠心病患者TET诊断结果阳性与阴性仅与血管狭窄程度≥75%狭窄的节段数目有统计学差异(P=0.016)。结论:CCTA诊断冠心病较TET有更高的诊断准确性和较低的诊断假阳性和假阴性,对有症状的疑诊冠心病患者CCTA的诊断具有更重要作用。     

Triage of patients with suspected coronary artery disease using multislice computed tomography

RATIONALE AND OBJECTIVES: Several studies have shown that multislice computed tomography (MSCT) has a high sensitivity and specificity for detecting coronary artery stenoses. The aim of the present study was to investigate whether MSCT can reliably triage patients with suspected coronary artery disease (CAD) to coronary artery bypass grafting (CABG), percutaneous coronary intervention (PCI), or no revascularization. MATERIALS AND METHODS: A total of 123 patients with suspected CAD who were referred for conventional coronary angiography (CATH) additionally underwent MSCT (16*0.5 mm detector collimation). Therapeutic decisions made on the basis of CATH and MSCT strictly following current guidelines for treatment of CAD were compared with decisions made by a cardiac surgeon and an interventional cardiologist. Only MSCTs with at least adequate image quality in all coronary segments were included in the analysis (94/123). RESULTS: Decisions made on the basis of MSCT and CATH according to guidelines did not differ significantly (agreement of 88%, 82 of 94, P = .319). The therapeutic decisions made by the interventional cardiologist and the cardiac surgeon based on CATH differed significantly (overall agreement of 79%, 74 of 94 cases, P < .001; cardiologist: 78% PCI and 22% CABG versus surgeon: 38% PCI and 62% CABG), whereas there was 100% agreement regarding decisions for or against invasive treatment. CONCLUSIONS: MSCT shows good agreement with CATH in triaging patients with suspected CAD to CABG, PCI, or no revascularization. The choice of revascularization procedure is significantly more strongly influenced by whether an interventional cardiologist or a cardiac surgeon makes the decision than by the diagnostic test on which the decision is based.     

Assessment of left ventricular function and mass in patients undergoing computed tomography (CT) coronary angiography using 64-detector-row CT: comparison to magnetic resonance imaging

PURPOSE: To quantify left ventricular function and mass derived from retrospectively ECG-gated 64-detector-row computed tomography coronary angiography data sets in comparison to cine magnetic resonance (MR) imaging as the reference standard. We hypothesized that the administration of beta-blockers prior to multidetector computed tomography (MDCT) coronary angiography has a significant impact on left ventricular functional parameters. MATERIAL AND METHODS: Multiplanar reformations in the short-axis orientation were calculated from axial contrast-enhanced CT images in 21 patients (16 male, five female; age range 41-75 years, mean 64.3+/-6.8 years) referred for CT coronary angiography. Patients whose heart rates exceeded 60 bpm received 5 mg bisoprolol orally 1 hour before the MDCT examination. In case of insufficient heart-rate reduction, up to four vials (20 mg) of metoprolol were injected intravenously. The end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF), cardiac output (CO), and left ventricular mass (LVM) of the reformatted images were analyzed compared to volumetric measurements based on continuous short-axis steady-state free-precession cine MR sequences (TR 3 ms, TE 1.5 ms, FA 60 degrees ). RESULTS: On average, each patient received 15.5 mg metoprolol (range 0-20 mg) and 3.85 mg bisoprolol (range 0-5 mg). The mean heart rate was 56+/-5 bpm during CT and 73+/-9 bpm during MRI examination. This difference was statistically significant (P<0.05). Mean EDV and ESV measured on MDCT were significantly higher compared to MR (MDCT vs. MR: EDV 164.2+/-52.5 vs. 144.2+/-46.7 ml, ESV 77.3+/-46.6 vs. 63.8+/-47.3 ml; P<0.05). Mean EF and CO derived from MDCT images were significantly lower compared to MR (MDCT vs. MR: EF 55.4+/-11.8 vs. 59.3+/-15.4%, CO 4822+/-779 vs. 5755+/-1267 ml; P<0.05). Mean SV and LVM were not significantly different between both methods (MDCT vs. MR: SV 86.8+/-18.1 vs. 80.3+/-15.6 ml, P = 0.44; LVM 132.4+/-42.5 vs. 138.7+/-39.1 g, P = 0.31). CONCLUSION: Left ventricular volumes assessed by the newest-generation MDCT scanners are significantly higher compared with MRI, whereas ejection fraction and cardiac output are significantly lower in MDCT. This appears to be a result of the frequent application of beta-blockers prior to MDCT examinations.     

Comparison of 64-slice computed tomography angiography and coronary angiography for the detection and assessment of coronary artery disease in patients with angina: A systematic review

BackgroundCoronary artery disease (CAD) is the leading cause of death in Western countries. It presents itself in various ways, the commonest being angina. According to the Royal College of Radiologist referral guidelines, Coronary Angiography (CA) is currently the gold standard for diagnosis and evaluation of CAD. However, due to the invasive nature and expense of CA there is a perceived need for a primary non-invasive imaging modality to supersede it. Computed tomography angiography (CTA), utilising 64-slice technology, may be a less invasive alternative to CA.AimTo consider the research evidence for the current gold standard diagnostic test for CAD. Specifically, which is more sensitive and specific for detecting CAD in patients with angina; 64-slice CTA or CA?Inclusion CriteriaProspective, non-randomised control trials and diagnostic accuracy studies comparing 64-slice CTA and CA were included. Participants were adults with angina with suspected or known CAD.MethodAn electronic search of the databases; AMED, CINAHL, Cochrane Library, EMBASE, MEDLINE and Science Direct, was conducted between January 2004 and April 2012. Secondary hand-searching of grey literature was undertaken. Two reviewers independently determined studies for inclusion, assessed quality, using SIGN50, and extracted data. Diagnostic value of 64-slice CTA and CA was compared and analysed at patient and segment level.ResultsTen studies were included in the critical review enrolling 1188 patients. At patient level sensitivity for 64-slice CTA ranged from 88% to 100%, specificity 64–92%, PPV 86–97% and NPV 76.9–100%. At segment level sensitivity for 64-slice CTA ranged from 73% to 100%, specificity 83–98%, PPV 47–90% and NPV 89–100%ConclusionAt both patient and segment level, 64-slice CTA is a highly sensitive and specific non-invasive alternative to CA for diagnosis of significant stenosis in patients with angina. For standalone diagnosis of CAD current research would support its adoption as the new gold standard. It is unlikely that CTA will replace CA for revascularisation patients as angiography and angioplasty are often performed concurrently.     

Diagnostic accuracy of 64-slice computed tomography coronary angiography in patients with low-to-intermediate risk

PURPOSE: Our aim was to evaluate the diagnostic accuracy of 64-slice computed tomography coronary angiography (MSCT-CA) for detecting significant stenosis (>or=50% lumen reduction) in a population of patients at low to intermediate risk. MATERIALS AND METHODS: We studied 72 patients (38 men, 34 women, mean age 53.9+/-8.0 years) with atypical or typical chest pain and stratified in the low-to intermediate risk category. MSCT-CA (Sensation 64 Cardiac, Siemens, Germany) was performed after IV administration of 100 ml of iodinated contrast material (Iomeprol 400 mgI/ml, Bracco, Italy). Two observers, blinded to the results of conventional coronary angiography (CAG), assessed the MSCT-CA scans in consensus. Diagnostic accuracy for detecting significant stenosis was calculated. RESULTS: CAG demonstrated the absence of significant disease in 70.1% of patients (51/72). No patient was excluded from MSCT-CA. There were 37 significant lesions on 1,098 available coronary segments. Sensitivity, specificity and positive and negative predictive value of MSCT-CA for detecting significant coronary artery on a per-segment basis were 100%, 98.6%, 71.2% and 100%, respectively. All patients with at least one significant lesion were correctly identified by MSCT-CA. MSCT-CA scored 15 false positives on a per-segment base, which affected only marginally the per-patient performance (only one false positive). CONCLUSIONS: We concluded that 64-slice CT-CA is a diagnostic modality with high sensitivity and negative predictive value in patients at low to intermediate risk.