Coronary stenosis detection by 16-slice computed tomography in heart transplant patients: comparison with conventional angiography and impact on clinical management

OBJECTIVES: We sought to find a non-invasive alternative to conventional coronary angiography (CCA) for serial detection and follow-up of coronary stenosis due to cardiac allograft vasculopathy in heart transplant patients. BACKGROUND: Cardiac allograft vasculopathy is the main factor limiting long-term success of heart transplantation. It is usually detected by CCA. Multislice computed tomography (MSCT) coronary angiography has recently proven effective for the diagnosis of coronary stenosis in non-transplant patients. METHODS: Fifty-three consecutive heart transplant patients underwent MSCT within 24 h before or after their annual routine CCA. Only angiographic segments >1.5 mm were considered for analysis; the coronary arterial tree was divided into nine segments. Three patients were excluded because of technical failure. RESULTS: Of the 450 angiographic coronary segments, 432 (96%) were evaluable by MSCT. Of the nine coronary stents in seven patients, only three, including one intrastent restenosis, were correctly evaluated by MSCT, and two intrastent restenoses were missed. Complete analysis of the coronary tree was possible for 44 (88%) of the 50 patients. For detection of coronary stenosis >50%, sensitivity was 83%, specificity 95%, positive predictive value 71%, negative predictive value 95%, and accuracy 93%. In the 22 patients with strictly normal MSCT, no stenosis was found by CCA. CONCLUSIONS: Our study suggests the following guidelines already applied in our institution: 16-slice MSCT can replace CCA in de novo heart transplant patients and patients with strictly normal MSCT at follow-up. Significant wall or lumen changes observed on annual MSCT or stents require further investigation by CCA.     

Usefulness of multidetector row spiral computed tomography with 64- x 0.6-mm collimation and 330-ms rotation for the noninvasive detection of significant coronary artery stenoses

Eighty-four patients with suspected coronary artery disease were studied to determine the accuracy of noninvasive coronary angiography using a multidetector computed tomographic scanner with 64- x 0.6-mm collimation and 330-ms gantry rotation. All coronary artery segments with a diameter >1.5 mm were assessed with respect to stenoses >50% decreased diameter. Results were compared with quantitative coronary angiographic findings. After exclusion of unevaluable coronary segments (4%), multidetector computed tomography demonstrated a sensitivity of 93%, a specificity of 97%, and a negative predictive value of 100% in a per-segment analysis. In a per-artery analysis, 15 of 336 arteries (4%) were unevaluable. Sensitivity and specificity in evaluable arteries were 95% and 93%, respectively. In a per-patient analysis (81 of 84 patients included), sensitivity and specificity were 96% and 91%, respectively.     

Diagnostic value of the 16-detector row multislice spiral computed tomography for the detection of coronary artery stenosis in comparison to invasive coronary angiography

OBJECTIVES: The aim of this study was to determine the diagnostic accuracy of 16-slice multislice spiral computed tomography (MSCT) of the coronaries and to provide data in a real clinical setting. Previous 16-slice MSCT studies presented data excluding patients with calcification, vessels of < 1.5 or 2 mm, and segments with impaired image quality. By including these data for 16-slice MSCT, a direct comparison with new data from 64-slice MSCT is possible. METHODS AND RESULTS: Sixty two patients with suspected or known coronary artery disease (CAD) were prospectively enrolled and underwent computed tomography angiography (CTA) and invasive coronary angiography (ICA). All vessels were evaluated for the presence of a significant coronary artery stenosis (>50%) using the American Heart Association (AHA) 15-segment model. From the evaluation of 917 segments, sensitivity, specificity, and positive and negative predictive value (NPV) (positive predictive value [PPV] and NPV) for the presence of relevant coronary stenosis were 73, 98, and 71 and 98% per segment and 94, 90, and 91 and 93% per patient, respectively. The influence of age, gender, body surface area (BSA), heart rate (HR), stents, and Ca(2+)-score value was analyzed. High Ca(2+)-score values were the only statistically significant predictor for impaired diagnostic accuracy. CONCLUSIONS: In summary, CTA with evaluation of all vessel segments in a broad spectrum of patients allowed accurate and fast noninvasive coronary artery evaluation, including evaluation of stented segments. These data are very similar to those published recently for 64-slice scanners.     

Comparison of 16 slice multi-detector computed tomography and breath hold 3D magnetic resonance angiography in the detection of coronary stenosis

Objective To compare 16-slice multi-detector spiral computed tomography (MDCT) and breathhold 3D magnetic resonance (MR) coronary angiography in the visualization of coronary arteries and the accuracy of detecting significant (> 50%) coronary stenoses in patients with suspected coronary artery disease. Methods Forty patients were examined by 16-slice CT (GE, Lightspeed 16) and MR (GE,Twinspeed) within 3 days; 31 of them underwent conventional coronary angiography (CAG) within 2 weeks after CT and MR scan. CT was performed with 16×1.25 mm detector collimation, 0.5 s rotation time and images were reconstructed at 60%-75% of the cardiac cycle. MR was performed with breath hold 3D FIESTA (TR4.0 ms, TE1 .7 ms, flip angle 65, slice thickness 3 mm, FOV 280 mm, matrix 256×192). Mean heart rate was 63±5.8 bpm andβ-blocker was used in 24 patients. MR and CT image quality was evaluated in 9 coronary segments (RCA1, RCA2, RCA3, LM, LAD1, LAD2, LAD3, LCX1, LCX2) using a four-point grading scale. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy were calculated for detection of significant stenosis using CAG as the gold standard. Results 16-slice CT showed higher image quality in most coronary segments except RCA2. Forty-three segments were diagnosed as significant stenosis by CAG, 36 and 27 of these were correctly detected by CT and MR respectively. Sensitivity, specificity, positive predictive value, and negative predictive value of 16-slice CT and MR for detecting significant stenosis were 83%, 84%. 49%, 97%. and 63%, 90%, 55%, 93%, respectively. Conclusion Sixteen-slice CT showed higher image quality in most coronary segments excepted for middle RCA. 16-slice CT had higher sensitivity than MR for detection of coronary significant stenosis, whereas MR had higher specificity than CT. Both CT and MR showed high negative predictive value, which is useful for excluding coronary stenosis in symptomatic patients. (J Geriatr Cordial 2006; 3(1): 24-28)     

Detection of coronary artery stenoses using multi-detector CT with 16x0.75 collimation and 375 ms rotation

Aims Insufficient spatial and temporal resolutions have limitedimage quality and accuracy of multi-detector CT (MDCT) for coronaryartery visualization and detection of stenoses. We assessedthe accuracy of a new 16-slice scanner with 370 ms rotationand 0.75 mm collimation for detection of coronary stenosesusing an analysis approach based on coronary artery segments. Methods and results Fifty consecutive patients scheduled fordiagnostic coronary angiography in stable clinical conditionand sinus rhythm were enrolled. All patients with a heart rate>60 b.p.m. received 100 mg atenolol p.o. and upto four doses of 5 mg metoprolol i.v. before the scan.MDCT was performed using 16x0.75 mm collimation, 120 kV,and ECG-gated tube current modulation. Ninety millilitres ofcontrast agent was injected intravenously. MDCT images werevisually analysed using the 16-segment coronary artery modelof the American Heart Association and compared with invasive,quantitative coronary angiography in a blinded fashion. A significantstenosis was assumed if the diameter reduction was 50%. Meanheart rate was 58 b.p.m. during MDCT. After exclusion oftwo patients with not fully evaluable data sets, MDCT correctlyidentified at least one coronary stenosis in all 25 patientswith significant coronary lesions in angiography and correctlydemonstrated the absence of stenoses in 19/23 patients (sensitivity100%, specificity 83%). Sensitivity and specificity for all50 patients were 93 and 83%, respectively. On a per-segmentbasis, nine coronary segments distal of total occlusions and128 coronary segments with a reference diameter <1.5 mmwere excluded from the analysis. Twenty-eight of the included663 segments (4%) were unevaluable due to calcification or motionartefact. In the remaining 635 segments, 50/53 stenoses weredetected by MDCT (sensitivity 94%, specificity 96%, negativepredictive value 99%, positive predictive value 69%). Conclusion Increasing temporal and spatial resolutions of MDCTlead to improved evaluation and diagnostic accuracy for detectionof coronary stenoses.     

Noninvasive coronary imaging and assessment of left ventricular function using 16-slice computed tomography

In recent years, multislice computed tomography (MSCT) has been demonstrated to be a feasible imaging modality for noninvasive coronary angiography and left ventricular function analysis. The present study evaluated overall performance of 16-slice MSCT in the detection of significant coronary artery disease, stent, or bypass graft stenosis in combination with global left ventricular function analysis. Forty-five patients underwent 16-slice MSCT. Multislice computed tomograms were used to evaluate the presence of significant coronary artery stenoses (>/=50% decrease in luminal diameter) in native coronary segments, bypass grafts, and coronary stents and were compared with conventional coronary angiograms. In addition, left ventricular ejection fraction was calculated and compared with 2-dimensional echocardiography. MSCT was performed successfully in all patients. A close correlation between MSCT and 2-dimensional echocardiography was demonstrated for the assessment of left ventricular ejection fraction (y = 0.93x +3.33, r = 0.96, p <0.001). A total of 298 of native coronary artery segments (94%) were evaluated with MSCT, whereas 81 of 94 grafts (85%) and 41 of 52 coronary stents (79%) were also evaluated. For all segments, overall sensitivity, specificity, and positive and negative predictive values were 85%, 89%, 71%, and 95%, respectively. In conclusion, 16-slice MSCT is a feasible modality for noninvasive evaluation and exclusion of coronary artery disease in patients who present with chest pain.     

Diagnostic accuracy of 64-slice computed tomography for detecting angiographically significant coronary artery stenosis in an unselected consecutive patient population: comparison with conventional invasive angiography.

BACKGROUND: Multislice computed tomography (MSCT) is a promising noninvasive method of detecting coronary artery disease (CAD). However, most data have been obtained in selected series of patients. The purpose of the present study was to investigate the accuracy of 64-slice MSCT (64 MSCT) in daily practice, without any patient selection. METHODS AND RESULTS: Using 64-slice MSCT coronary angiography (CTA), 69 consecutive patients, 39 (57%) of whom had previously undergone stent implantation, were evaluated. The mean heart rate during scan was 72 beats/min, scan time 13.6 s and the amount of contrast media 72 mL. The mean time span between invasive coronary angiography (ICAG) and CTA was 6 days. Significant stenosis was defined as a diameter reduction of > 50%. Of 966 segments, 884 (92%) were assessable. Compared with ICAG, the sensitivity of CTA to diagnose significant stenosis was 90%, specificity 94%, positive predictive value (PPV) 89% and negative predictive value (NPV) 95%. With regard to 58 stented lesions, the sensitivity, specificity, PPV and NPV were 93%, 96%, 87% and 98%, respectively. On the patient-based analysis, the sensitivity, specificity, PPV and NPV of CTA to detect CAD were 98%, 86%, 98% and 86%, respectively. Eighty-two (8%) segments were not assessable because of irregular rhythm, calcification or tachycardia. CONCLUSION: Sixty-four-MSCT has a high accuracy for the detection of significant CAD in an unselected patient population and therefore can be considered as a valuable noninvasive technique.     

Non-invasive evaluation of coronary artery bypass grafts using 16-row multi-slice computed tomography with 188 ms temporal resolution

BACKGROUND: Cardiac multi-slice computed tomography (MSCT) scanners permit visualization of the coronary arteries and coronary artery bypass grafts. The latest MSCT generation with true 16-detector slices (Sensation 16 Speed 4 D, Siemens, Forchheim, Germany) provides improved temporal and spatial resolution, as well as significantly reduced scan time. To assess, whether this technical improvement has also an impact on image quality and accuracy of MSCT diagnosis in patients with previous coronary artery bypass graft (CABG) surgery the following study was conducted. METHODS AND MATERIAL: Thirteen consecutive patients (pts) (10 male, 3 female, mean age 62 +/- 6.4 [55-73] years, heart rate 68 +/- 11 [52-88] bpm) and a total number of 43 coronary bypass grafts (11 arterial, 32 venous grafts) were examined by MSCT (gantry rotation time 375 ms). In addition to the analysis of coronary bypass grafts, 13 coronary segments (sgts) were evaluated in each patient (n = 169 sgts). MSCT results were compared with coronary angiography. RESULTS: Forty-one of 43 bypass grafts (95%) were analyzable by MSCT. In conventional angiography 16 of 43 (37%) grafts were occluded. Sixteen of them were correctly diagnosed by MSCT (sensitivity 100%). One graft showed a 50% anastomosis stenosis which was also detected. Twenty-five of 27 grafts without severe lesion showed no significant stenosis in MSCT (specificity 93%, positive predictive value (PPV) 89%, negative predictive value (NPV) 100%). Ninety of 108 (83%) high-grade stenosis (>70%) of the native coronary vessels were correctly detected (sensitivity 83%, PPV 78%). From the 61 sgts without high grade stenosis 36 were correctly classified (specificity 59%, NPV 67%). If sgts number 8, 9 and 10, which are normally not target for revascularization, are excluded sensitivity rises to 89%, specificity to 71%, PPV to 87% and NPV to 75%. The correct clinical diagnosis (absence or presence of a high grade stenosis of at least one bypass graft) was achieved in all patients. CONCLUSIONS: True 16-slice MSCT with faster gantry rotation time allows detection of lesions in coronary artery bypass grafts with high sensitivity and specificity. The evaluation of native vessels in pts with known CAD remains a diagnostic challenge. However, the correct clinical diagnosis was achieved in all pts. MSCT is a non-invasive tool to assess coronary artery bypass grafts.     

Diagnostic accuracy of noninvasive coronary angiography using 64-slice spiral computed tomography

OBJECTIVES: The aim of our study was to evaluate the diagnostic accuracy of multislice computed tomography (MSCT) coronary angiography using a new 64-slice scanner. BACKGROUND: The new 64-slice MSCT scanner has improved spatial resolution of 0.4 mm and a faster rotation time (330 ms) compared to prior MSCT scanners. METHODS: We studied 70 consecutive patients undergoing elective invasive coronary angiography. Patients were excluded for atrial fibrillation, but not for high heart rate, coronary calcification, or obesity. All vessels were analyzed, including those <1.5 mm in diameter; MSCT lesions were analyzed quantitatively as well as by a qualitative scale and compared to quantitative coronary angiography (QCA). Results were also analyzed for significant coronary stenoses (over 50% luminal narrowing) by segment, by artery, and by patient. RESULTS: All scans showed diagnostic image quality. Of 1,065 segments, 935 (88%) could be evaluated, and 773 of 935 (83%) could be assessed quantitatively by both MSCT and QCA. The Spearman correlation coefficient between MSCT and QCA was 0.76 (p < 0.0001). Bland-Altman analysis demonstrated a mean difference in percent stenosis of 1.3 +/- 14.2%. A total of 26% of patients had calcium scores above 400 Agatston U, 25% had heart rates >70 beats/min, and 50% were obese. Specificity, sensitivity, and positive and negative predictive values for the presence of significant stenoses were: by segment (n = 935), 86%, 95%, 66%, and 98%, respectively; by artery (n = 279), 91%, 92%, 80%, and 97%, respectively; by patient (n = 70), 95%, 90%, 93%, and 93%, respectively. CONCLUSIONS: Our results indicate high quantitative and qualitative diagnostic accuracy of 64-slice MSCT in comparison to QCA in a broad spectrum of patients.     

Detection of coronary artery stenosis using 40-channel computed tomography with multi-segment reconstruction

Coronary angiographic studies performed with 16-channel multidetector computer tomographic scanners have demonstrated accurate detection of coronary vessel stenosis but are limited by a significant number of non-evaluable segments. To date, only single-center experience with multidetector computer tomography has been reported. We performed a prospective, blinded study at 2 institutions to determine the feasibility and diagnostic accuracy of coronary angiography using 40-channel multidetector computer tomography with multi-segment reconstruction for the detection of obstructive coronary artery disease (CAD). Multidetector computer tomographic studies were performed in 85 patients who were referred for invasive coronary angiography with clinically suspected CAD. Datasets were analyzed by blinded, independent review. Of 1,145 segments that were suitable for analysis as determined by angiography, 1,045 (91.3%) were evaluable on multidetector computer tomography. Segment-based sensitivity, specificity, and positive and negative predictive values for detecting > or =50% luminal stenoses were 86%, 97%, 75%, and 97%, respectively. The area under the receiver-operating characteristic curves for the detection of > or =50% angiographic stenosis by multidetector computer tomography was 0.94. In a patient-based analysis, the sensitivity, specificity, and positive and negative predictive values for detecting subjects with > or =1 segment with > or =50% stenosis were 98%, 93%, 94% and 93%, respectively. In conclusion, coronary angiography using 40-channel multidetector computer tomography with multi-segment reconstruction accurately detects coronary segments and patients with obstructive CAD, with a small number of non-evaluable cases.     

New diagnostic technique in multi-slice computed tomography for in-stent restenosis: pixel count method

OBJECTIVES: A diagnostic technique to objectively determine coronary in-stent stenosis was developed with multi(16)-slice computed tomography (MSCT), and it was compared with coronary angiography (CAG) in clinical cases. BACKGROUND: MSCT is expected to replace coronary angiography as a new non-invasive examination. Evaluation of highly calcified or in-stent lesions with CT is generally thought to be difficult. METHODS: Twenty lesions among 16 consecutive patients that were implanted with coronary stents were examined with both MSCT and CAG at follow-up. The minor axis cross sections of the stents were reconstructed at intervals of 1.5 mm with multiplanar reformation (MPR). The pixel with a higher CT value than the lowest CT value in the standard cross section at the proximal site out of stent was counted to determine the presence/absence of a stenotic lesion. RESULTS: Among 20 lesions, one case was not able to be evaluated with MSCT. MSCT correctly detected 3 of 4 cases with in-stent stenosis (sensitivity 75%), and 14 of 16 cases with no in-stent stenosis (specificity 88%, negative predictive value 93%, positive predictive value 75%). If analysis was made per-artery, sensitivity and specificity were 100% (3 of 3) and 87% (13 of 15), respectively, for detection of in-stent stenosis. CONCLUSIONS: This study was performed to examine a unique diagnostic technique: pixel count method, for coronary in-stent stenosis with MSCT. It showed that the coronary in-stent stenosis could be determined when stent struts were clearly imaged. Further examination is required with various stents, especially those with a diameter of 3.0 mm or smaller.     

多层螺旋CT诊断冠状动脉狭窄的价值和限度

目的 评价多层螺旋CT(MSCT)在冠状动脉狭窄诊断中的价值和限度.方法 临床诊断或可疑冠心病的65例患者接受冠状动脉MSCT检查,采用回顾性心电门控、0.5 s/转的螺旋扫描、单扇区重建算法和静脉注射对比剂,其检查结果与导管法,冠状动脉造影进行对照.结果 在65例患者的冠状动脉889节段(直径≥1.5 mm)中,CT图像满足管腔评价为795节段(占89.4%).对于CT图像满足管腔评价的冠状动脉节段,MSCT对冠状动脉中度和中度以上狭窄(≥50%)诊断的敏感度和特异度分别为88.6%和95.1%,阳性预测值和阴性预测值分别为82.7%和96.9%;MSCT显示冠状动脉高度狭窄(≥75%)的敏感度和特异度分别为90.7%和97.6%,阳性预测值和阴性预测值分别为82.1%和98.9%.结论 如果冠状动脉CT图像满足管腔评价,MSCT对冠状动脉狭窄的诊断准确性很高.MSCT可用于冠状动脉狭窄的初步诊断和介入治疗的筛选.     

Diagnostic accuracy of computed tomography coronary angiography in routine practice

OBJECTIVES: The recent newer advances in computed tomography have dramatically changed our approach to imaging cardiac disease. This study sought to compare the diagnostic value of 16-multi-detector spiral computed tomography (MSCT) for detecting coronary artery stenosis. METHODS: A total of 88 consecutive patients (52 men, mean age 68 +/- 8 years) with atypical chest pain, stable angina or suspicion of ischaemia at stress test were studied by MSCT and invasive coronary angiography (ICA). The MSCT images and multiplanar reconstructions were analysed regarding the presence of > or =50% coronary artery lesion. RESULTS: All 88 scans obtained at a mean heart rate of 68 +/- 8 beats/min were interpretable. Sixteen coronary segments were evaluated in each patient. Of the 1320 segments examined, 148 (11%) showed poor image quality.A total of 150 significant lesions were detected using ICA, and 80 of 150 (53%) were detected by MSCT. Sensitivity, specificity, positive and negative predictive values were as follows: 53%, 97%, 68%, and 94%. Fifty-four patients had > or =50% coronary stenosis.The diagnosis was confirmed by MSCT in 42 patients and correctly ruled out in 30. By patient-based analysis, positive and negative predictive values were 91% and 71%. CONCLUSION: Although its specificity is high, the sensitivity of 16-slice MSCT for detecting > or =50% coronary stenosis in non-selected patients submitted to ICA is rather low suggesting that for daily practice the diagnostic value of this technique should be improved.     

Accuracy of multislice computed tomography coronary angiography: a pooled estimate

A PUBMED search was performed for peer-reviewed studies published in English from 2002 through August 2006. Accuracy parameters for detection of obstructive coronary artery disease by MSCT (multislice computed tomography) coronary angiography were analyzed on patient and segment basis. Pooled estimates of sensitivity (SN), specificity, positive predictive value, and negative predictive value (NPV) in patient-based analyses were 93%, 82%, 83%, and 92%, respectively. For 64/40-slice MSCT the respective accuracy estimates were 96%, 91%, 93%, and 96% and were better compared with 16-slice MSCT. Also, more segments were evaluated by 64-slice MSCT (96%) compared with 16-slice MSCT (86%). The SN and NPV of MSCT coronary angiography for patients with low coronary artery calcium (CAC) score were 92% and 99% compared with 77% and 89% for patients with high CAC score. The accuracy estimates for MSCT in studying coronary artery by-pass grafts and intracoronary stents showed a SN and NPV of 97% and 97% for graft occlusion or stenosis and only 71% and 93% respectively for in-stent restenosis. Diagnostic accuracy of MSCT coronary angiography has improved with the newer 64-slice versions. High CAC scores can affect the accuracy of MSCT coronary angiography. Although the accuracy of MSCT in evaluating native vessel and graft disease has improved significantly, its reliability in studying intracoronary stents remains uncertain.     

64层螺旋CT血管成像与冠状动脉造影对冠心病诊断价值的对比研究

目的评价64层螺旋CT在冠状动脉造影方面的诊断价值。方法58例临床诊断或可疑冠心病患者行64层螺旋CT冠状动脉成像检查,分别对左主干、左前降支、回旋支和右冠状动脉及其分支的重建图像行影像学评价,所有患者均行常规选择性冠状动脉造影检查作为对照。结果58例患者共757(87.0%)节段的冠状动脉(血管直径≥1.5 mm)成像,638节段(84.3%)可用于多层螺旋CT和冠状动脉造影定量分析。冠状动脉造影共发现狭窄101节段,多层螺旋CT发现狭窄104节段,多层螺旋CT对冠状动脉狭窄诊断的敏感性为86.1%,特异性为96.8%。结论64层螺旋CT冠状动脉造影可作为诊断冠状动脉病变的一种无创筛选方法。     

Noninvasive detection of coronary lesions using 16-detector multislice spiral computed tomography technology: initial clinical results

OBJECTIVES: The aim of our study was to evaluate the feasibility of detecting coronary artery lesions using a new computed tomography (CT) scanner with 16 detectors and faster gantry rotation. BACKGROUND: Computed tomography angiography of the coronaries permits assessment of the coronaries; however, image quality is still impaired by motion artifacts and calcifications. METHODS: Sixty patients scheduled for conventional coronary angiography (CCA) were additionally studied by multislice spiral computed tomography (MSCT).Calcium scores and a contrast-enhanced visualization of the coronaries were performed and analyzed regarding evaluability, presence of coronary artery lesions, and correct clinical diagnosis. RESULTS: Calcium scoring was successful in all patients; 58 of 60 patients had a diagnostic contrast-enhanced scan. Mean calcium score was 506 +/- 743 Agatston score equivalent (ASE); 13 of 58 (22%) patients had an ASE >or=1,000, 46 of 58 (78%) patients <1,000. In 763 coronary segments, CCA detected a total of 75 lesions >or=50%. The MSCT correctly assessed 54 of these. Twenty-one lesions were missed or incorrectly underestimated. Sensitivity was 72%, specificity 97%. When restricting analysis to patients with an ASE <1,000, 40 significant lesions >or=50% were seen on CCA, and MSCT correctly detected 39 lesions (sensitivity 98%, specificity 98%). Regardless of any threshold, the correct clinical diagnosis could be obtained in 58 of 60 (97%) of all patients. CONCLUSIONS: In individuals with low-to-moderate amounts of coronary artery calcium, 16-detector CT coronary angiography has high sensitivity and specificity for the diagnosis of significant coronary artery stenosis.     

64层螺旋CT血管成像在冠心病诊断中的应用

目的评价64层螺旋CT(MSCT)血管成像在冠心病诊断中的应用价值。方法选择80例冠心病或可疑冠心病患者行心电门控的MSCT冠状动脉成像,在特定工作站完成图像重建,并与冠状动脉造影结果对照,分析64层MSCT冠状动脉成像在诊断冠心病中的应用价值。结果80例患者中共1200个冠状动脉节段,其中1096个冠状动脉节段可供临床诊断分析,104(8．7%)个冠状动脉节段因图像质量差不能进行诊断分析。在所有可供分析的78例患者中MSCT诊断冠心病的敏感度、特异度、阳性预测值、阴性预测值和诊断准确度分别是96．1%、85．2%、92%和92．3%。1096个可供评价的冠状动脉节段中MSCT识别直径狭窄≥50%病变的敏感度、特异度、阳性预测值、阴性预测值分别为93．2%、89．3%、85．6%、95．2%和92．3%。结论64层MSCT冠状动脉成像对冠心病的诊断有良好的准确性。     

64排螺旋CT冠状动脉成像在冠状动脉病变诊断中的临床研究

目的探讨和评价64排螺旋CT（MSCT）在冠心病诊断中的有效性。方法选取在3周内行64排MSCT和冠状动脉造影（CAG）检查的临床可疑或确诊冠心病的患者（两项检查平均间隔时间9d）114例，其中男性62例，平均年龄65岁。将MSCT和CAG检查结果进行分析，管腔狭窄≥50％定义为明显狭窄。结果在114例患者中，CAG检出至少有1处明显狭窄的患者106例，其中单支病变占33％（38例），多支病变占60％（68例）。MSCT检出其中的104例（诊断准确度95％）。按节段分析，MSCT诊断冠状动脉明显狭窄的灵敏度、特异度、阳性预测值、阴性预测值分别为87％、96％、86％、96％。以各冠状动脉分析，MSCT诊断冠状动脉明显狭窄的灵敏度、特异度、阳性预测值、阴性预测值分别为96％、94％、95％、96％。MSCT与CAG在发现冠状动脉明显狭窄上差异无统计学意义（P〉0．05）。结论64排MSCT诊断冠状动脉狭窄的准确度较高，作为一种冠心病诊断的无创筛查手段，有广泛的临床应用价值。     

Diagnostic accuracy of multislice computed tomography for the detection of coronary artery disease in diabetic patients

BACKGROUND: Diabetes mellitus is an important risk factor for coronary artery disease. Cardiac multislice computed tomography (MSCT) permits visualization of the coronary arteries with good sensitivity and specificity. However, at present, there are no data whether MSCT allows an accurate assessment of coronary arteries of diabetic patients, in comparison to nondiabetic patients. Thus, we compared the catheter-controlled MSCT results from diabetic and nondiabetic patients in a cohort of 116 patients with regard to sensitivity, specificity, positive predictive value, and negative predictive value, as well as image quality. METHODS AND MATERIALS: Twenty-two diabetic patients (age, 64.6+/-8.5 years; number of risk factors, 3.4+/-1.1) and 94 nondiabetic patients (age, 64.2+/-9.2 years; number of risk factors, 2.4+/-1.0) were examined by MSCT (Sensation 16 Speed 4 D, Siemens, Forchheim, Germany; gantry rotation time, 375 ms) and invasive coronary angiography. MSCT results were compared, blinded to the results of the coronary angiography with regard to the presence or absence of a significant stenosis (>50%) in a modified American Heart Association 13-segment model. Image quality was assessed on a qualitative scale between 1 (very good) and 5 (invisible) for each segment. RESULTS: Sensitivity, specificity, positive predictive value, and negative predictive value were statistically not different in diabetic and nondiabetic patients (0.85/0.98/0.92/0.96 vs. 0.84/0.97/0.91/0.95). One diabetic and three nondiabetic patients had to be excluded from analysis. Diabetic patients had relevantly more risk factors (P < .05), but calcium scoring was not different in both groups (Agatston score 1090+/-1278 vs. 798+/-1033). The image quality in both cohorts was comparable. CONCLUSIONS: MSCT allows the assessment of the coronary arteries noninvasively in diabetic patients with a good sensitivity and specificity, and diabetes does not have an impact on the number of evaluable segments. Thus, MSCT is a noninvasive tool in the care of these patients.     

Role of 16-multidetector computed tomography in the assessment of coronary artery stenoses: A prospective study of consecutive patients

BACKGROUND: Recent studies have demonstrated a high sensitivity (S) of 16-multidetector computed tomography (16-MDCT) for the detection of significant coronary artery stenoses. Whether these results are applicable to clinical practice is unclear. Therefore, the aim of the present study was to compare 16-MDCT angiography with conventional coronary angiography (CCA) for the detection of significant coronary artery stenoses in a consecutive series of patients. METHOD: A total of 93 consecutive patients (mean [+/- SD] age 59+/-9 years), in whom CCA was performed for stable angina pectoris, underwent 16-MDCT angiography (16x0.75 mm, table feed 6.5 mm/s, rotation time 0.42 s; Sensation 16, Siemens Medical Solutions, Germany) the day before performing CCA. Patients with diabetes mellitus, serum creatinine level higher than 132.6 mumol/L and/or acute coronary syndromes were excluded. Two observers blinded to CCA results evaluated MDCT angiograms according to standard criteria. Segment-based (13 segments per patient) and patient-based (at least one stenosis greater than 50% lumen diameter reduction) analyses were performed. RESULTS: A total of 1209 segments were analyzed. Of these segments, 173 (14%) were excluded due to poor image quality or massive calcification. In 86 segments, CCA revealed significant coronary artery stenosis (greater than 50% diameter reduction). However, 16-MDCT detected only 47 of these, resulting in a S of 55% and a specificity (SP) of 97% (positive predictive value 64%; negative predictive value 96%). On a patient-based analysis, the S increased to 89%, whereas the SP still remained high (87%). CONCLUSION: In this relatively large consecutive cohort, S for the detection of significant coronary artery stenoses was moderate on a segment-based analysis but increased on a patient-based analysis using 16-MDCT. In contrast, SP was high in both analyses, supporting the use of 16-MDCT for the exclusion of significant coronary artery stenoses. Further improvement of spatial and temporal resolution in MDCT technology may lead to a lower exclusion rate and higher S.