Multislice computed tomography coronary angiography at a local hospital: Pitfalls and potential

PURPOSE: To evaluate whether the favorable results achieved with multislice computed tomography (MSCT) of coronary arteries at larger centers could be paralleled at a local hospital. MATERIAL AND METHODS: Fifty consecutive patients with suspected coronary artery disease scheduled for invasive investigation with quantitative coronary angiography (QCA) at a university hospital underwent MSCT with a 16-slice scanner at a local hospital. Diagnostic accuracy of MSCT for coronary artery disease was assessed using a 16-segment coronary artery model with QCA as the gold standard. RESULTS: Segments with diameter <2 mm, as defined by QCA, segments distal to occlusions, and stented segments were excluded. Of the remaining 489 segments, 73 (15%) were not assessable with MSCT. Sensitivity, specificity, and positive and negative predictive values for significant (>50%) stenosis for the 416 assessable segments were 92%, 82%, 53%, and 98%, respectively. CONCLUSION: Our beginners' experience demonstrated favorable results regarding sensitivity and negative predictive value. The positive predictive value, however, was unsatisfactory. Calcifications were identified as the most important factor for false-positive results with MSCT. With widespread use of MSCT coronary angiography, there is a risk of recruiting patients without significant coronary artery disease to unnecessary and potentially harmful invasive procedures.     

Thoracic cardiovascular imaging with 16-row multislice Computed Tomography and retrospective ECG-gating. Technical note

PURPOSE: To apply the retrospective ECG-gating to the 16-row MSCT scan of intrathoracic vessels. MATERIALS AND METHODS: Fourty-eight patients underwent MSCT with a new 16-row scanner (Sensation 16-Siemens) for the study of the great intrathoracic vessels. In group 1 (33 patients) a retrospectively ECG-gated protocol was applied; in the control-group 2 (15 patients) a conventional MSCT protocol for thoracic imaging was applied. Images were scored regarding 1) the presence or absence of artefacts determined by breath-hold, beam hardening and mis-triggering; 2) the visualisation (optimal, mild and poor) of great intrathoracic vessels (aorta, pulmonary arteries and veins); 3) the visualisation (presence or absence) of proximal, mid and distal coronary arteries (left main, left anterior descending, circumflex, and right coronary artery). RESULTS: Ascending aorta showed motion artefacts in 3 (20%) cases in group 2 and none in group 1. In group 1, proximal LAD, CX, and RCA were assessable in 94%, 91%, and 91%, respectively. Left main coronary artery was assessable in 32 (97%) and 10 (67%) cases for group 1 and 2, respectively. In group 2, proximal segments of left anterior descending (LAD), circumflex (CX), and right coronary artery (RCA), were almost not assessable. CONCLUSIONS: The retrospectively ECG-gated 16-row MSCT provides more information regarding ascending aorta and coronary arteries.     

Accuracy and reliability of quantitative measurements in coronary arteries by multi-slice computed tomography: experimental and initial clinical results.

AIM: To evaluate the accuracy of non-invasive measurements within coronary arteries by multi-slice computed tomography (MSCT). We present experimental as well as clinical data. MATERIALS AND METHODS: Silicon tubes simulating coronary arteries (outer diameter 6 mm, lumen diameter within stenotic area 2 mm) were used for experimental studies. Clinical data were derived from 15 patients in whom vessel diameters were assessed by MSCT, intracoronary ultrasound (ICUS) and quantitative coronary angiography (QCA). MSCT were performed in a Somatom Volume Zoom(trade mark)CT system (Siemens, Forchheim, Germany) at 2 collimated slice widths (2.5 mm, 1.0 mm). RESULTS: Outer silicon tube diameters were overestimated by MSCT (6.56 mm +/- 0.32 mm). All measurements revealed significantly better results on 1.0 collimation compared to 2.5 mm collimation (outer diameter: 6.36 mm +/- 0.22 mm vs 6.76 mm +/- 0.27 mm, P < 0.0001; lumen diameters: 1.83 mm +/- 0.14 mm vs 1.51 mm +/- 0.19 mm, P < 0.0001). The comparison of vessel diameters within human coronary arteries revealed comparable results between ICUS and MSCT (4.89 mm +/- 0.67 mm vs 4.91 mm +/- 0.71 mm, P = 0.79, r = 0.79, P < 0.0001). QCA-measurements showed significantly lower results (3.67 +/- 0.71, P < 0.0001, r = 0.62, P < 0.001). CONCLUSIONS: Experimental as well as initial clinical results indicate acceptable reliability and accuracy of quantitative measurements by MSCT, when using thin collimated slice widths. Partial volume effects lead to a systematic overestimation of vessel size. MSCT has the potential to become an important non-invasive diagnostic tool in patients with coronary artery disease.     

Multislice computed tomographic coronary angiography: experience in a UK centre

AIM: To evaluate the technique of coronary angiography with retrospectively electrocardiogram (ECG)-gated four-slice helical computed tomography (CT). MATERIALS AND METHODS: Within 1 month of undergoing routine day-case diagnostic coronary angiography, 30 consecutive patients also underwent retrospectively ECG-gated multislice CT coronary angiography. This enabled direct comparison of seven segments of proximal and mid-coronary artery for each patient by two blinded assessors. Each segment of coronary artery from the multislice CT image was evaluated initially for "assessability" and those segments deemed assessable were subsequently investigated for the presence or absence of a significantly (n=70%) stenotic lesion. RESULTS: Overall 68% of proximal and mid-coronary artery segments were assessable. The sensitivity and specificity of four-slice CT coronary angiography in assessable segments for detecting the presence or absence (n=70%) of stenoses were 72 and 86%, respectively. These results correspond to a positive predictive value of 53% and a 93% negative predictive value. If the 32% of non-assessable segments are added into the calculation then the sensitivity and specificity fall to 49 and 66%, respectively. CONCLUSION: Although multislice CT coronary angiography is a promising technique, the overall assessability and diagnostic accuracy of four-slice CT acquisition is not sufficient to justify routine clinical use. Further, evaluation should investigate the benefit of the reduction in temporal and spatial resolution offered by 16 and 32 slice acquisition.     

Coronary artery stenosis quantification using multislice computed tomography

RATIONALE AND OBJECTIVES: Reliable noninvasive detection of stenoses with multislice computed tomography (MSCT) is feasible. This study's aim was to analyze the agreement, correlation, and reliability of MSCT with conventional coronary angiography as the reference standard for quantification of coronary artery stenoses. MATERIALS AND METHODS: A total of 118 significant (at least 50%) coronary artery stenoses with a reference vessel diameter of at least 1.5 mm in 62 patients were analyzed by MSCT using 16 detector rows (Aquilion, Toshiba, Otawara, Japan), multisegment reconstruction, and voxel sizes of 0.35x0.35x0.5 mm. The degree of stenosis on MSCT and quantitative coronary angiography (QCA) was measured by correlating the difference between the reference vessel diameter (average of 2 measurements directly proximal and distal to the stenosis) and the stenotic vessel diameter to the reference vessel diameter. RESULTS: Correlation between the percent diameter stenosis determined by MSCT (78.2+/-13.6%) and QCA (76.0+/-14.8%) was significant (P<0.001) but only moderately so (R=0.51). Bland-Altman analysis revealed no systematic under- or overestimation with MSCT but large limits of agreements (+/-27.6%). Also the limits of agreement for interobserver agreement (reliability) of MSCT data were considerably large (+/-24.8%). Among the 27 coronary artery stenoses with a reference diameter of at least 3.5 mm, there was improved correlation (R=0.80) and the limits of agreement between MSCT and QCA were significantly smaller (+/-17.3%, P<0.008). The agreement between MSCT and QCA was not significantly different for stenoses with no calcification or only calcium spots (+/-28.2%) as compared with those with moderate-or-severe calcifications (+/-27.3%; P=0.8). MSCT allowed correct classification of coronary stenoses into low-grade (below 75%) and high-grade stenoses (at least 75%), in 62% (73 of 118). CONCLUSIONS: The accuracy and reliability of coronary artery stenosis quantification with MSCT using isotropic voxel sizes and multisegment reconstruction is still too low to recommend routine clinical application because of rather low agreement, correlation, and reliability. Despite these limitations, the current results demonstrate the potential of MSCT for reliable and accurate quantification of coronary artery stenoses in the near future provided that further improvements in spatial and temporal resolution will be achieved.     

Evaluation of computed tomography coronary angiography in patients with a high heart rate using 16-slice spiral computed tomography with 0.37-s gantry rotation time

The aim of our study is to evaluate computed tomography (CT) coronary angiography in patients with a high heart rate using 16-slice spiral CT with 0.37-s gantry rotation time. We compare the image quality of patients whose heart rates were over 70 beats per minute (bpm) with that of patients whose heart rates were 70 bpm or less. Sixty patients with various heart rates underwent retrospectively ECG-gated multislice spiral CT (MSCT) coronary angiography. Two experienced observers who were blind to the heart rates of the patients evaluated all the MSCT coronary angiographic images and calculated the assessable segments. A total of 620 out of 891 (69.6%) segments were satisfactorily visualized. On average, 10.3 coronary artery segments per patient could be evaluated. In 36 patients whose heart rates were below 70 bpm [mean 62.2 bpm±5.32 (standard deviation, SD)], the number of assessable segments was 10.72±2.02 (SD). In the other 24 patients whose heart rates were above 70 bpm [mean 78.6 bpm±8.24 (SD)], the corresponding number was 9.75±1.74 (SD). No statistically significant difference was found in these two subgroups t test, P>0.05. The new generation of 16-slice spiral CT with 0.37-s rotation time can satisfactorily evaluate the coronary arteries of patients with high heart rates (above 70 bpm, up to 102 bpm).     

Comparison of image quality in contrast-enhanced coronary-artery visualization by electron beam tomography and retrospectively electrocardiogram-gated multislice spiral computed tomography

RATIONALE AND OBJECTIVES: To compare the image quality of electron beam tomography (EBT) and multislice spiral CT (MSCT) for coronary artery visualization. MATERIALS AND METHODS: Two groups of 30 patients without coronary stenoses were studied by MSCT (4 x 1 mm collimation) or EBT (3 mm slice thickness). Contrast-to-noise ratio (CNR), overall length of the visualized arteries and vessel length free of motion artifacts were measured. RESULTS: Length of visualized arteries was equal in MSCT and EBT. In EBT, longer segments were depicted free of motion artifacts (MSCT: 73%, EBT: 92% of visualized length, P< 0.001) and CNR was significantly higher than in MSCT (15.4 vs. 9.0; P< 0.001). In both modalities, vessel diameters correlated closely to quantitative coronary angiography. CONCLUSIONS: EBT and MSCT permit reliable coronary artery visualization and measurement of vessel diameters. For the used scan protocol, MSCT images had a lower CNR and were more frequently affected by motion.     

256层CT前瞻性及回顾性心电门控ECG电流调制技术的应用

目的：探讨256层CT前瞻性及回顾性心电门控ECG电流调制技术图像质量及辐射剂量,探讨其临床应用价值。方法：160例患者分为3组：A组50例,采用回顾性心电门控技术,关闭ECG电流调控;B组50例,采用回顾性心电门控螺旋扫描,开启ECG电流调控;C组60例,采用前瞻性心电门控横轴面扫描,心率≤70次/分(32例)时数据...     

Diagnostic value of multislice computed tomography angiography in coronary artery disease: a meta-analysis

PURPOSE: To perform a meta-analysis of the diagnostic value of multislice CT (MSCT) angiography in the detection of coronary artery disease (CAD) when compared to conventional coronary angiography. MATERIALS AND METHODS: A search of PubMed and MEDLINE databases for English literature was performed. Only studies with at least 10 patients comparing MSCT angiography with conventional coronary angiography in the detection of CAD were included. Diagnostic value of MSCT angiography compared to coronary angiography was compared and analyzed at segment-, vessel- and patient-based assessment. RESULTS: 47 studies (67 comparisons) met the criteria and were included in our study. Pooled overall sensitivity, specificity and 95% confidence interval for MSCT angiography in the detection of CAD were 83% (79%, 89%), 93% (91%, 96%) at segment-based analysis; 90% (87%, 94%), 87% (80%, 93%) at vessel-based analysis; and 91% (88%, 95%), 86% (81%, 92%) at patient-based analysis, respectively. Diagnostic accuracy of MSCT angiography in evaluating assessable segments was significantly improved with 64-slice scanners when compared to that with 4- and 16-slice scanners (p<0.05). CONCLUSION: Our meta-analysis showed that MSCT angiography has potential diagnostic accuracy in the detection of CAD. Diagnostic performance of MSCT angiography has been significantly improved with the latest 64-slice CT, with resultant high qualitative and quantitative diagnostic accuracy. 16-slice CT was limited in spatial resolution which makes it difficult to perform quantitative assessment of coronary artery stenoses.     

心率对256层CT前瞻性心电门控冠状动脉成像质量的影响

目的：探讨心率对256层螺旋CT前瞻性心电门控冠状动脉成像质量的影响,并与回顾性心电门控进行对照分析。方法：156例患者行前瞻性心电门控冠状动脉检查,73例行回顾性心电门控冠状动脉检查,所有病例按心率分为＜60次/分,60～69次/分,70～79次/分,80～89次/分,90～99次/分及≥100次/分共6组。对所有冠...     

自适应前瞻性心电门控双源CT冠状动脉成像的初步研究

目的 探讨双源CT自适应前瞻性心电门控技术冠状动脉成像的可行性.方法 对31例患者行双源CT前瞻性心电门控技术冠状动脉成像.将患者分为2组:A组心率≤75次/min,选择R-R间期的70%扫描;B组心率＞75次/min,选择R-R间期的40%扫描.2名有经验的放射医师,利用双盲法、以4分法评定系统对冠状动脉15支分支血管成像质量进行评分,统计方法采用独立样本t检验.计算2组总CT剂量指数(CTDIvol)及有效剂量(ED)均值.结果 31例患者,共纳入分析的血管节段为437段,共有408支(93.4%)冠状动脉节段可满足影像学评价,29支(6.6%)冠状动脉节段不能满足影像学评价,其中A组共226个节段,12个节段(5.3%)不能评价,B组共211个节段,17个节段(8.1%)不能评价;31例患者冠状动脉均分3.57±0.64;其中A组冠状动脉均分(3.65±0.39)与B组冠状动脉均分(3.41±0.43)之间差异无统计学意义(t=1.62,P=0.12);在A、B 2组各段冠状动脉图像质量对照时,只有第10段2组图像质量差异有统计学意义(t=3.8,P＜0.05).CTDIvol均值为(18.88±5.04) mGy,有效剂量为(4.31±1.05) mSv.结论 双源CT自适应前瞻性心电门控冠状动脉成像技术在无需控制心率情况下可得到满足临床诊断的冠状动脉图像,加之低的辐射剂量有望成为冠状动脉CT成像常规的检查方法.     

Accuracy of 16-slice multi-detector CT to quantify the degree of coronary artery stenosis: assessment of cross-sectional and longitudinal vessel reconstructions

BACKGROUND: Sixteen-slice multi-detector computed tomography (MDCT) permits reliable noninvasive detection of significant coronary stenosis based on qualitative visual assessment. The purpose of this study was to determine the accuracy of MDCT to quantify the degree of coronary stenosis as compared to quantitative coronary angiography (QCA) using two different reconstruction methods. METHODS: We studied 69 coronary artery lesions from 38 consecutive patients that underwent 16-slice MDCT as a part of research study, which enrolled consecutive subjects scheduled for clinically indicated invasive coronary angiography. Nine coronary artery lesions with motion artifacts, heavily calcified plaques or stents were excluded from the analysis. The degree of stenosis was calculated by two independent readers non-blinded to the location of the stenosis, but blinded to the results of the QCA. MDCT luminal diameters were measured in cross-sectional multi-planar reformatted (CS-MPR) images created perpendicular to the centerline of the vessel and in 5 mm thin-slab maximum intensity projections (MIP) parallel to the long axis of the vessel. Both MDCT methods were compared against QCA. RESULTS: The mean degree of stenosis as measured by MDCT was closely correlated to QCA for both methods (CS-MPR versus QCA: 61 +/- 23% versus 64 +/- 29%; r2 = 0.83, p < 0.001 and MIP versus QCA: 64 +/- 22% versus 64 +/- 29%; r2 = 0.84, p < 0.001 for MIP. Bland-Altman analysis demonstrated a negative bias of the degree of stenosis of -2.8 +/- 12% using CS-MPR and a minimally positive bias of 0.6 +/- 12% for MIP. In stratified analysis for lesion severity (mild, 0-40%; moderate, 41-70% or severe, > 70%) the agreement between both CS-MPR and MIP was high when compared to QCA (kappa = 0.74 and 0.71, respectively). CONCLUSION: Multi-detector spiral CT permits accurate quantitative assessment of the degree of coronary stenosis in selected data sets of sufficient quality using both cross-sectional and longitudinal vessel reconstructions.     

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.     

多层螺旋CT无创性冠状动脉造影图像质量分析及冠状动脉病变评价

目的分析多层螺旋CT无创性冠状动脉造影图像质量的主要影响因素,以正确评价冠状动脉病变。方法64例患者行多层螺旋CT冠状动脉造影检查,用回顾性心电门控选择最佳相位窗,并分别以容积再现（VR）、最大密度投影（MIP）、曲面重建（CPR）等后处理技术将冠状动脉分为15个节段进行分析。结果显示血管直径大于2mm的冠状动脉节段共960个,能满足影像学评价的节段共884个（92．08％）;不能满足影像学评价的节段共76个（7．92％）;64例中的58例（90．63％）冠状动脉CTA图像质量均为2级或1级,其余6例（9．37％）冠状动脉CTA图像质量为3级,共发现冠状动脉存在中、重度狭窄者44例（占68．75％）,其中单支病变28例,双支病变16例;另发现冠状动脉存在轻度狭窄者16例（占25．00％）,其中单支病变8例,双支病变8例;冠状动脉未见明确狭窄者4例（6．25％）。结论高质量的MSCT无创性冠状动脉造影对冠状动脉病变有较高的诊断价值。     

Coronary artery bypass graft imaging using ECG-gated multislice computed tomography: comparison with catheter angiography

AIM: To compare the value of multislice computerized tomography (MSCT) in imaging coronary artery bypass grafts (CABGs) by direct quantitative comparison with standard invasive angiography. METHODS: Using MSCT, 50 consecutive patients who had previously undergone CABG surgery and had recently undergone invasive angiography for recurrent angina pectoris, were studied further using MSCT after intravenous injection of non-ionic contrast agent; cardiac imaging was performed during a single breath-hold. Graft anatomy was quantified, using both quantitative coronary angiography (QCA) and MSCT, by different investigators blinded to each other. Reproducibility was quantified using the standard error of the measurement expressed as a percentage in log-transformed values (CV%) and intraclass correlation (ICC). RESULTS: All 150 grafts were imaged using MSCT; only 4 patent grafts were not imaged using selective angiography. Good agreement was achieved between MSCT and QCA on assessment of proximal anastomoses (CV% 25.2, ICC 0.84), mid-vessel luminal diameter (CV% 15.5, ICC 0.91) and aneurysmal dilations (CV% 14.3). Reasonable agreement was reached on assessment of distal anastomoses (CV% 26.7, ICC 0.66) and categorization of distal run-off (ICC 0.73). Good agreement was observed for stenoses of over 50% luminal loss (CV% 8.7, ICC 0.97) but agreement on assessment of less severe lesions was poor (CV% 208.7, ICC 0.51). CONCLUSION: This study demonstrates that CABGs can be quantitatively evaluated using MSCT, and that significant lesions present in all CABG segments can be reliably identified. Agreement between MSCT and QCA for lesions of less than 50% luminal loss was poor.     

Coronary artery stenosis: direct comparison of four-section multi-detector row CT and 3D navigator MR imaging for detection--initial results

PURPOSE: To prospectively compare the diagnostic accuracy of multi-detector row computed tomography (CT) and of three-dimensional (3D) navigator magnetic resonance (MR) imaging in patients referred for conventional coronary angiography for detection of coronary artery stenosis. MATERIALS AND METHODS: All patients gave written informed consent for the study, which was approved by the local ethics committee. Twenty-seven patients underwent multi-detector row CT and 3D navigator free-breathing MR imaging a mean of 5 days before undergoing invasive coronary angiography. The acquired multi-detector row CT and MR images were graded for the presence of greater than 50% stenosis in vessels larger than 1.5 mm in diameter. The diagnostic accuracies of the two examinations were compared with that of quantitative coronary angiography (QCA) by using the McNemar test. RESULTS: Owing to claustrophobia, MR images were not acquired in one patient; thus, 26 patients were included for analysis. According to QCA findings, 21 of the 26 patients had significant coronary artery disease and 58 (20%) of a total of 294 coronary artery segments larger than 1.5 mm in diameter had significant (>50%) stenosis. Multi-detector row CT had significantly higher sensitivity (46 [79%] of 58 segments) than MR imaging (36 [62%] segments, P < .05) for detection of segments with significant stenosis. Conversely, MR imaging had significantly higher specificity (198 [84%] of 236 segments) than did CT (168 [71%] segments, P < .001) for exclusion of segmental coronary artery stenosis. Both examinations had high negative predictive value for exclusion of segmental stenosis: 93% (168 of 180 segments) for CT and 90% (198 of 220 segments) for MR imaging. The overall diagnostic accuracy of MR imaging (80% [234 of 294 segments]) was significantly higher than that of CT (73% [214 segments], P < .05). CONCLUSION: MR imaging had significantly higher diagnostic accuracy than multi-detector row CT in the evaluation of coronary artery stenosis. Both techniques have high negative predictive value, making them particularly useful for ruling out coronary artery disease in symptomatic patients.     

Image quality in a standardized algorithm for minimally invasive coronary angiography with multislice spiral computed tomography

PURPOSE: To report our experience with a standardized approach to pharmacologic heart rate control and image postprocessing for computed tomographic coronary angiography (CTCA) with multislice computed tomography (MSCT). METHOD: Two experienced observers used transaxial tomograms and maximum-intensity projections to classify coronary segments (12 per patient, 135 consecutive patients) for degree of stenosis. One factor affecting image quality was identified for each segment that could not be assessed. RESULTS: Nine patients (7%) were excluded for technical reasons. Of 1,512 segments from 126 patients, 1,086 (72%) were assessable (8.6 per patient). Of 300 segments from 25 patients who also had selective coronary angiography, CTCA was able to assess 211 (70%) and detected significant disease in 27 (82% sensitivity, 96% specificity, 73% positive predictive value, and 97% negative predictive value). Vessel caliber, heart rate, and Agatston score were associated with inability to assess 426 coronary segments (28%). CONCLUSION: Heart rate and Agatston score are important predictors of the ability to assess proximal and midcoronary segments by CTCA with MSCT.     

MSCT在左心室功能及冠脉主干径线测定中的应用价值

目的：探讨MSCT成像技术在左心室功能及冠脉径线测量中的应用价值。方法：对28例临床拟诊冠心病的患者进行回顾性心电门控MSCT心脏扫描，分别对左心室容积、室壁厚度、射血分数和室壁收缩增厚率及左、右冠脉主支内径进行测量，MSCT测得结果与超声心动图和数字减影冠脉造影进行对比。结果：MSCT测得的左心室舒张末期容量(EDV)、收缩末期容量(ESV)、射血分数(EV)、心肌收缩末期厚度(EST)、心肌舒张末期厚度(EDT)及室壁增厚率与超声心动图相关性较好，测量结果MSCT略小于超声心动图，但两者相比无显著性差异。MSCT与数字减影冠脉造影左、右冠脉主支内径的测量值间无显著性差异。结论：MSCT在左心室功能及冠脉主干径线测定中具有很高的临床应用价值。     

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.