Multislice CT imaging of anomalous coronary arteries

The purpose of the present study was to evaluate the role of 16 multislice computed tomography (MSCT) to identify the origin of anomalous coronary arteries and to confirm their anatomic course in relation to the great vessels. Accuracy of coronary artery disease (CAD) detection was a secondary aim and was tested with conventional angiograms (CA) serving as standard of reference. Two hundred and forty-two consecutive patients referred for noninvasive coronary CT imaging were reviewed for the study. Sixteen patients (6.6%) with anomalous coronary arteries were detected and included as the study group. MSCT and CA images were analyzed in a blinded fashion for accuracy of anomalous artery origin and path detection. Results were compared in a secondary consensus evaluation. Accuracy ratios to detect CAD with MSCT in all vessels were calculated. Coronary anomalies for all 16 patients were correctly displayed on MSCT. CA alone achieved correct identification of the abnormality in only 53% (P=0.016). Sensitivity and specificity of MSCT to detect significantly stenosed vessels was 90 and 92%. 16-MSCT is accurate to delineate abnormally branching coronary arteries and allows sufficiently accurate detection of obstructive coronary artery disease in distal branches. It should therefore be considered as a prime non-invasive imaging tool for suspected coronary anomalies.     

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.     

Influence of a small field-of-view size on the detection of coronary artery calcifications with MSCT: in vitro and in vivo study

The purpose of this study is to asses the impact of small field-of-view (FOV) sizes on the detection of coronary artery calcifications using multislice-spiral computed tomography (MSCT). First, a static chest phantom containing calcium inserts was scanned 10 times using a standardized scan protocol. Secondly, 50 patients (28 male, 63.6±10.6 years) underwent cardiac MSCT using the same protocol. Images were reconstructed with three different FOV sizes (180×180, 220×220, 380×380 mm²). Coronary calcium scoring and risk stratification were performed for each image series. In the phantom study, the Agatston score calculated with a FOV size of 180×180 mm² was 657.80±20.05. At a FOV of 220×220 mm² and 380×380 mm², the corresponding values were 657.04±21.36 and 655.04±20.74, respectively. The corresponding values in the patient study were 541.65±869.87, 541.91±872.57 and 536.61±867.81. No statistically significant differences in the calcium score were found comparing different FOV sizes. Significantly more lesions (p=0.00149) were detected in the patient study. Comparing the different FOV sizes of 180×180 mm² and 220×220 mm² (380×380 mm²), four (six) patients had to be assigned to different risk groups. The use of small FOV sizes resulted in an improved detection of coronary calcifications influencing the risk stratification for further cardiac events in MSCT coronary calcium scoring.     

Congenital anomalies of the coronary arteries: imaging with contrast-enhanced, multidetector computed tomography

The objective of this study is to evaluate multidetector CT (MDCT) in detecting and characterizing anomalous coronary arteries. Forty-four patients with anomalies of the coronaries were selected from a total of 1758 individuals examined with ECG-gated 4- and 16-row MDCT including thinMIP, MPR and VRT post-processing. Twenty-eight patients showed origin and course anomalies of the central coronary segments, and in this subgroup 13 were judged as malignant because of interarterial courses between the aortic root and the pulmonary trunk, either of the right coronary artery (n=11) or the left coronary artery (n=2). Twelve non-hemodynamic anomalies were found, affecting the coronary origins only (n=10) or the peripheral vessels courses (n=2). Four arteriovenous fistulas were present, all of them with complex arterial feeders. Regardless of vessel anatomy, coronary opacification was always possible by means of the systemic contrast agent, and the aberrant coronary arteries were visualized synoptically in direct relation to the great mediastinal vessels. In contrast to MDCT, selective cannulation and final diagnosis was possible in only 11 of the 20 catheter angiograms performed (accuracy of 55.0%). In conclusion, its non-invasiveness and precise visualization makes MDCT the standard of reference for evaluating anomalous coronary arteries.     

Detection and evaluation of intracranial aneurysms with 16-row multislice CT angiography: comparison with conventional angiography

The aim of our study was to compare multidetector row computed tomography (CT) angiography (MDCTA) with digital subtraction angiography (DSA) in the detection and characterization of intracranial aneurysms. Between September 2005 and May 2007, 55 consecutive patients with suspected intracranial aneurysms underwent conventional DSA and MDCTA. Thirty-two women and 23 men were enrolled in the study. The mean patient age was 54 (range = 26–79 years). All MDCTA and DSA images were independently evaluated on a workstation by two radiologists, who had 8 and 6 years of experience in CT vascular imaging and angiography. Using DSA as the gold standard, the sensitivity and specificity of CT angiography was calculated for each reader with 95% confidence intervals. The sensitivity was also calculated for aneurysms smaller than 3 mm with 95% confidence intervals. The agreement between the readers for detecting aneurysms was calculated using kappa statistics. A kappa statistic greater than 0.75 was considered an excellent agreement beyond chance, a kappa statistic of 0.4–0.75, fair to good agreement, and a kappa statistic less than 0.4, poor agreement. At DSA, 64 aneurysms were present in 50 patients involved in the study; seven patients had two aneurysms each, and four patients had three aneurysms each. In five patients, no aneurysm was detected by using MDCTA and DSA, and evaluations were considered as true negative by MDCTA. These five patients also had negative findings at repeat DSA. For readers 1 and 2, the sensitivity of MDCT in detecting aneursyms were 96.9% (95% CI = 89.3–99.1%; 62 of 64) and 98.4 % (95% CI = 91.7–99.7%; 63 of 64), respectively. The spescificity was100% (95% CI = 99.7–100%; 1,256 of 1,256) for both readers. The kappa value indicating interobserver agreement was in the category of excellent (kappa = 0.99 (95% CI = 0.97–1). Regarding the aneurysms smaller than 3 mm, for readers 1 and 2, the sensitivities were 84.6% (95% CI = 57.8–95.7%; 11 of 13) and 92.3% (95% CI = 66.7–98.6; 12 of 13), respectively. MDCTA is accurate in the detection and characterization of intracranial aneurysms and can be used as a reliable alternative imaging technique to DSA. A strategy of using CT angiography as the primary method, with DSA reserved for any cases of uncertainty, appears safe and reliable.     

320排640层CT在耳部畸形诊断中的临床应用价值探讨

目的:探讨320排640层动态容积CT在耳部畸形诊断上的临床应用价值。方法:收集2011-01～2012-01间行320排640层动态容积CT耳部检查先天性耳部病变患者31例共44耳,使用Toshiba Aquilion One动态容积CT机,采用160×0.5容积扫描模式。采集到的数据,常规进行1.0 mm横断面重建,高分辨率算法(sharp verysharp或bone)。结果:外耳道闭锁16例18耳,同时16例中伴有鼓室形态异常4耳,听小骨形态异常3耳,鼓室并听小骨形态异常1耳,患耳侧乳突呈板障型者2耳。外耳道狭窄4例5耳。内耳形态异常或畸形10例19耳。结论:320排640层动态容积CT先进的软硬件技术,评价内耳畸形可靠性进一步提升。     

16层螺旋CT冠状动脉成像:毫秒相位重建法的应用

目的:探讨毫秒相位重建法在16层螺旋CT冠状动脉成像中的应用价值。方法:对18例利用常规百分比相位重建法重建冠状动脉CT图像失败或不理想的患者,使用毫秒级重建方法进行成像,探讨毫秒相位重建法应用的价值。结果:在显示冠状动脉血管节段总数上和能够达到诊断要求的血管节段的显示率方面,毫秒相位重建的方法均明显优于百分比相位重建,两者具有统计学意义(P<0.05)。结论:毫秒重建法可用于常规百分比相位选择法重建效果达不到诊断要求情况下的一种很有效的辅助措施。     

Influence of heart rate on diagnostic accuracy and image quality of 16-slice CT coronary angiography: comparison of multisegment and halfscan reconstruction approaches

The lower the heart rate the better image quality in multislice computed tomography (MSCT) coronary angiography. We prospectively assessed the influence of heart rate on per-patient diagnostic accuracy and image quality of MSCT coronary angiography and compared adaptive multisegment and standard halfscan reconstruction. A consecutive cohort of 126 patients scheduled to undergo conventional coronary angiography was examined with 16-slice CT. For all heart rate groups, per-patient diagnostic accuracy was significantly higher for multisegment than halfscan reconstruction with values of 95 vs. 79% (p < 0.05, <65 bpm, 38 patients), 85 vs. 66% (p < 0.05, 65–74 bpm, 47 patients), and 78% vs. 41% (p < 0.001, >74 bpm, 41 patients). Differences in diagnostic accuracy between adjacent heart rate groups were only significant for halfscan reconstruction for the comparison between the 65–74 and >74 bpm group (p < 0.05). The vessel lengths free of motion artifacts were significantly longer with multisegment reconstruction in all heart rate groups and for all coronary arteries (p < 0.005). For noninvasive MSCT coronary angiography, both per-patient diagnostic accuracy and image quality decline with increasing heart rate, and multisegment reconstruction at high heart rates yields similar results as standard halfscan reconstruction at low heart rates.     

人工智能在冠状动脉CT血管成像后处理和诊断报告的初步评估

目的 探讨人工智能（AI）在冠状动脉CT血管造影（CCTA）的图像后处理和诊断报告中的应用价值。 方法 选取重庆医科大学附属第三医院于2019年4月至7月就诊的64例疑似冠心病患者,其中男性40例、女性24例,年龄（62.16±14.13）岁。所有患者均行CCTA扫描,按照李克特量表评分标准对原始图像质量进行评分,分别进行人工和AI图像后处理,比较二者的用时及合格率、诊断报告的用时及对冠状动脉斑块的诊断效能。 结果 CCTA扫描后,冠状动脉AI图像后处理的时间约3 min,合格率为92.2%（59/64）;人工后处理的时间为20~30 min。与人工处理相比,冠状动脉AI后处理的图像中冠状动脉管壁更光滑、小分支显示更全面、血管对比更清晰,并且能自动识别冠状动脉狭窄。冠状动脉AI图像的诊断报告在图像重建后即可完成（<1 min）,而人工的诊断报告需15 min左右才能完成。冠状动脉AI与人工对冠状动脉斑块检出的灵敏度几乎一致,分别为93.3%和92.0%;人工诊断报告对斑块检出的特异度达100%,而AI的特异度为93.8%。 结论 冠状动脉AI在图像后处理速度、图像质量及报告诊断的效率方面具有一定优势,有望成为CCTA分析的有效辅助工具。     

The evaluation of coronary artery-to-pulmonary artery fistula in adulthood on 256-slice CT coronary angiography: Comparison with coronary catheter angiography and transthoracic echocardiography

ObjectiveTo review the imaging features of coronary artery-to-pulmonary artery fistula (CPAF) on CT coronary angiography (CTCA) and evaluate its diagnostic performance compared with coronary catheter angiography (CCA) and transthoracic echocardiography (TTE).Materials and methodsWe retrospectively reviewed with a diagnosis of CPAF from among 19855 consecutive CCTA performed with 256-slice MDCT scanner for suspected coronary artery disease. CT images were evaluated for – origin, number, size and course (tubular/worm-like dilation/significant aneurysm formation/wall attachment sign) of fistula vessels, drainage site, drainage site imaging features (pierced sign, isodensity sign, smoke sign, jet sign), and main pulmonary artery (MPA) enlargement. 25 patients of CPAF also underwent CCA and 47 patients underwent TTE.ResultsThere were 72 patients with CPAF (0.36%) in our study, of which 44 were men and 28 were women, with mean age of 55.8 ± 13.2 years (range 22–85 years). CPAF originated from conus artery, left anterior descending artery (LAD), combined conus artery and LAD in 55, 67, 50 cases, respectively. Tubular dilation, worm-like dilation and aneurysm was seen in 14, 58 and 35 cases, respectively. Wall attachment sign was noted in 69 cases. All the cases demonstrated only a single drainage site, with left lateral wall, left anterolateral, anterior, right lateral and right anterolateral walls of MPA in 44, 21, 5, 1 and 1 cases, respectively. The mean diameter of the fistula drainage site was 2.6 ± 1.3 mm. Pierced sign, jet sign, smoke sign, isodensity sign was seen in 72, 46, 41 and 24 cases, respectively. MPA enlargement was seen in 20 patients. CCA showed CPAF in only 20 cases among 25 patients; while TTE showed CPAF in only 9 patients among 47 patients.ConclusionCTCA is competent in detecting and characterizing CPAF with an excellent diagnostic performance as the first imaging modality of choice, which is valuable for giving a distinct and intuitive explanation to patients and physicians and making an objective and exact assessment for further management.     

64排容积CT对成人冠状动脉起源异常的诊断价值

 目的 探讨64排容积CT对成人冠状动脉起源异常的诊断价值.方法 回顾分析3 030例成人冠状动脉CTA检查资料. 结果 3 030例冠脉CTA中,检查出冠状动脉起源异常70例,检出率为2.3%,其中冠状动脉起源于对侧冠状窦及窦外27例(38.5%);冠状动脉高位开口23例(32.8%);前降支、回旋支均开口于左冠状窦17例(24.3%);单一冠脉2例(均为单一左冠,其中1例合并左主干高开口,2.8%),回旋支开口于对角支及窦房结支开口于右冠状窦各1例(1.4%).结论 64排容积CT诊断冠状动脉起源异常是一种无创、安全、准确、经济的检查方法 .     

Diagnostic accuracy of 16-slice multidetector-row CT for detection of in-stent restenosis vs detection of stenosis in nonstented coronary arteries

The purpose of this study was to assess the diagnostic accuracy of 16-slice multidetector-row computed tomography (MDCT) for detecting in-stent restenosis. Fifty patients with 69 previously implanted coronary stents underwent 16-slice MDCT before quantitative coronary angiography (QCA). Diagnostic accuracy of MDCT for detection of in-stent restenosis defined as >50% lumen diameter stenosis (DS) in stented and nonstented coronary segments >1.5-mm diameter was computed using QCA as reference. According to QCA, 18/69 (25%) stented segments had restenosis. In addition, 33/518 (6.4%) nonstented segments had >50% DS. In-stent restenosis was correctly identified on MDCT images in 12/18 stents, and absence of restenosis was correctly identified in 50/51 stents. Stenosis in native coronary arteries was correctly identified in 22/33 segments and correctly excluded in 482/485 segments. Thus, sensitivity (67% vs 67% p=1.0), specificity (98% vs 99%, p=0.96) and overall diagnostic accuracy (90% vs 97%, p=0.68) was similarly high for detecting in-stent restenosis as for detecting stenosis in nonstented coronary segments. MDCT has similarly high diagnostic accuracy for detecting in-stent restenosis as for detecting coronary artery disease in nonstented segments. This suggests that MDCT could be clinically useful for identification of restenosis in patients after coronary stenting. Grant Funding: Dr Gerber was supported by a grant from the Fondation Nationale de la Recherche Scientifique of the Belgian Government (FRSM 3.4557.02).     

CT coronary angiography: influence of different cardiac reconstruction intervals on image quality and diagnostic accuracy

PURPOSE: To prospectively analyze image quality and diagnostic accuracy of different reconstruction intervals of coronary angiography using multislice computed tomography (MSCT). MATERIALS AND METHODS: For each of 47 patients, 10 ECG-gated MSCT reconstructions were generated throughout the RR interval from 0 to 90%, resulting in altogether 470 datasets. These datasets were randomly analyzed for image quality and accuracy and compared with conventional angiography. Statistical comparison of intervals was performed using nonparametric analysis for repeated measurements to account for clustering of arteries within patients. RESULTS: Image reconstruction intervals centered at 80, 70, and 40% of the RR interval resulted (in that order) in the best overall image quality for all four main coronary vessels. Eighty percent reconstructions also yielded the highest diagnostic accuracy of all intervals. The combination of the three best intervals (80, 70, and 40%) significantly reduced the nondiagnostic rate as compared with 80% alone (p=0.005). However, the optimal reconstruction interval combination achieved significantly improved specificities and nondiagnostic rates (p<0.05). The optimal combination consisted of 1.7+/-0.9 reconstruction intervals on average. In approximately half of the patients (49%, 23/47) a single reconstruction was optimal. In 18 (38%), 3 (6%), and 3 (6%) patients one, two, and three additional reconstruction intervals were required, respectively, to achieve optimal quality. In 28% of the patients the optimal combination consisted of reconstructions other than the three best intervals (80, 70, and 40%). CONCLUSION: Multiple image reconstruction intervals are essential to ensure high image quality and accuracy of CT coronary angiography.     

Visual and automatic grading of coronary artery stenoses with 64-slice CT angiography in reference to invasive angiography

The aim of this study was to assess the performance of a software tool for quantitative coronary artery analysis of computed tomography coronary angiography (CT-QCA) in comparison with invasive coronary angiography with quantitative analysis (CAG-QCA) as standard of reference. Two radiologists reviewed the CT angiography data sets (Siemens Sensation 64) of 25 patients, grading coronary artery stenoses visually and with a software tool (Circulation, Siemens). Twenty-three data sets with sufficient image quality were included in the final analysis. CAG revealed a total of 30 wall irregularities and 28 stenoses, of which 17 were graded as moderate and nine as hemodynamically significant. CT-QCA showed a better agreement to CAG-QCA, with a systematic overestimation of the degree of stenosis of 6.1% and limits of agreement of +36.1% and −23.9; the correlation coefficient was 0.82 (p < 0.0001). Using CT-QCA, sensitivity, specificity, and positive and negative predictive value were 89%, 100%, 89%, and 100%, respectively, for significant area stenoses greater than 75%. The positive predictive value for the visual assessment amounted to 53%. Interobserver variability between CT-QCA and visual assessment showed a kappa value of 0.72. In conclusion, software-supported CT-QCA makes it possible to quantify significant coronary artery stenoses automatically, with good agreement to CAG-QCA. Both Stephanie Busch and Thorsten R. C. Johnson contributed equally to the study.     

64排容积CT在冠状动脉成像中的临床应用

 目的 探讨64排容积CT在冠状动脉成像的临床应用及意义.方法 56例临床诊断及可疑诊断冠心病患者包括冠脉搭桥术后2例、PTCA术后6例,采用回顾性心电门控技术行64排容积CT冠脉成像检查,在不同心电相位窗利用多种后处理技术行冠状动脉重建并分析其病变,12例诊断为冠脉中重度狭窄的患者行选择性冠状动脉造影.结果 56例中心率＜75次/min的冠脉重建相位窗多数位于心动周期R波后75%,心率＞75次/min冠脉重建相位窗多数位于心动周期R波后45%,56例成功显示冠脉各主干(左主干、左前降支、左回旋支、右冠)221支,显示率98%;直径大于2 mm的分支(后降支、左室后支、对角支、钝缘支、窦房结支、圆锥支)237支;64排容积CT诊断冠状动脉中重度狭窄患者12例行选择性冠脉造影,11例结果同64排容积CT.结论 64排容积CT下的冠脉造影成像检查是一种安全、准确、经济的检查方法,可以作为可疑冠心病及冠心病的筛选普查及术后复查的首选方法.     

16层螺旋CT冠状动脉成像的技术与应用

目的:探讨多层螺旋CT冠状动脉造影(multislice spiral CT coromary angiography,MSCTCA)的成像技术和临床应用价值。方法:37例患者行MSCTCA检查,利用多种方法进行重建,分析影响冠状动脉图像质量的重要因素,MSCTCA对冠状动脉的显示能力,冠状动脉狭窄程度的评价,冠状动脉斑块性质的判断,冠状动脉的解剖变异,并了解桥血管和支架的通畅性。结果:容积再现图像最佳的显示相位窗为75%,左主干、左前降支重建的最佳相位为75%,右冠和左回旋支为50%~70%。MSCTCA能显示的管腔最小径1.5mm。对冠状动脉的解剖变异、冠状动脉狭窄的程度、斑块的性质及桥血管和内支架显示良好。结论:MSCTCA可作为冠心病介入治疗前的筛选,能能评价斑块的性质,在血运重建后的复查中也有很高的应用价值,并能提供冠状动脉其他病变的信息。     

16层螺旋CT冠状动脉成像的临床应用

目的:探讨16层螺旋CT冠状动脉(简称冠脉)成像在冠心病诊断中的临床价值。方法:选取50例临床诊断或可疑冠心病患者行16层螺旋CT冠状动脉造影检查(MSCTCA),先行冠脉钙化积分平扫,然后行冠脉增强扫描,选取一组质量最佳的薄层图像行冠脉三维重建,分析MSCTCA对冠状动脉狭窄性病变的显示能力,并对冠脉支架显示及通畅性进行评价。结果:冠脉钙化积分与其狭窄程度呈正相关,中度以上狭窄的冠脉钙化积分值明显高于轻度狭窄,其间有统计学显著性差异(P<0.001)。MSCTCA对诊断有临床意义的冠脉中度以上狭窄的敏感度、特异度、诊断准确率、阳性预测值、阴性预测值分别约89.6%、93.9%、92.6%、86.7%、95.4%。MSCTCA对冠脉支架显示良好,检出5例9根支架,其中2根支架不通畅,出现支架内再狭窄。结论:16层螺旋CT冠脉成像安全、无创,对评价冠状动脉狭窄、支架开放及通畅性等方面有着较高的临床应用价值,可作为冠心病筛查的有效手段以及介入和手术治疗后的随访手段。     

Quantitative parameters to compare image quality of non-invasive coronary angiography with 16-slice, 64-slice and dual-source computed tomography

Multi-slice computed tomography (MSCT) is a non-invasive modality to visualize coronary arteries with an overall good image quality. Improved spatial and temporal resolution of 64-slice and dual-source computed tomography (DSCT) scanners are supposed to have a positive impact on diagnostic accuracy and image quality. However, quantitative parameters to compare image quality of 16-slice, 64-slice MSCT and DSCT are missing. A total of 256 CT examinations were evaluated (Siemens, Sensation 16: n = 90; Siemens Sensation 64: n = 91; Siemens Definition: n = 75). Mean Hounsfield units (HU) were measured in the cavum of the left ventricle (LV), the ascending aorta (Ao), the left ventricular myocardium (My) and the proximal part of the left main (LM), the left anterior descending artery (LAD), the right coronary artery (RCA) and the circumflex artery (CX). Moreover, the ratio of intraluminal attenuation (HU) to myocardial attenuation was assessed for all coronary arteries. Clinical data [body mass index (BMI), gender, heart rate] were accessible for all patients. Mean attenuation (CA) of the coronary arteries was significantly higher for DSCT in comparison to 64- and 16-slice MSCT within the RCA [347 ± 13 vs. 254 ± 14 (64-MSCT) vs. 233 ± 11 (16-MSCT) HU], LM (362 ± 11/275 ± 12/262 ± 9), LAD (332 ± 17/248 ± 19/219 ± 14) and LCX (310 ± 12/210 ± 13/221 ± 10, all p < 0.05), whereas there was no significant difference between DSCT and 64-MSCT for the LV, the Ao and My. Heart rate had a significant impact on CA ratio in 16-slice and 64-slice CT only (p < 0.05). BMI had no impact on the CA ratio in DSCT only (p < 0.001). Improved spatial and temporal resolution of dual-source CT is associated with better opacification of the coronary arteries and a better contrast with the myocardium, which is independent of heart rate. In comparison to MSCT, opacification of the coronary arteries at DSCT is not affected by BMI. The main advantage of DSCT lies with the heart rate independency, which might have a positive impact on the diagnostic accuracy. Christof Burgstahler and Anja Reimann contributed equally to this work     

Non-invasive evaluation of coronary artery stent patency with retrospectively ECG-gated 64-slice CT angiography

The aim of our study has been to evaluate the ability of 64-slice computed tomographic angiography (CTA) to assess coronary artery stent patency, relative to selective coronary angiography (SCA). Fifty-five consecutive patients (age range 45–80 years) with 97 previously implanted coronary artery stents underwent 64-slice CTA. The 55 patients comprised 40 subjects (group A) who were referred for follow-up SCA at a mean interval of 9.6 months after stent positioning, and 15 subjects (group B) in whom SCA was clinically indicated. Stent evaluation was performed independently by two blinded readers in terms of image quality and presence of in-stent restenosis (ISR; lumen obstruction of ≥50%). SCA was performed in 41/55 patients; 14 patients refused to undergo SCA after the 64-slice CTA exam. A total of 88 stents in 74 segments were analyzed. Twenty-one of the 74 stented segments were of poor image quality and were not considered for further analysis. Sixty-four-slice CTA detected 12/16 ISR (sensitivity: 75%) and ruled out ISR in 32/37 cases (specificity: 86%). Sixty-four-slice CTA is a valuable modality for follow-up of coronary artery stent patency only in selected patients. Appropriate candidates for follow-up 64-slice CTA should be established based on stent diameter, stent material and type as well as HR and heart rhythm. However, given the number of non-assessable segments, further work would appear necessary before 64-slice CTA can be considered a suitable procedure for broad clinical application in the evaluation of coronary artery stent patency.