64-slice computed tomography coronary angiography in patients with high, intermediate, or low pretest probability of significant coronary artery disease.

OBJECTIVES: We assessed the usefulness of 64-slice computed tomography coronary angiography (CTCA) to detect or rule out coronary artery disease (CAD) in patients with various estimated pretest probabilities of CAD. BACKGROUND: The pretest probability of the presence of CAD may impact the diagnostic performance of CTCA. METHODS: Sixty-four-slice CTCA (Sensation 64, Siemens, Forchheim, Germany) was performed in 254 symptomatic patients. Patients with heart rates > or =65 beats/min received beta-blockers before CTCA. The pretest probability for significant CAD was estimated by type of chest discomfort, age, gender, and traditional risk factors and defined as high (> or =71%), intermediate (31% to 70%), and low (< or =30%). Significant CAD was defined as the presence of at least 1 > or =50% coronary stenosis on quantitative coronary angiography, which was the standard of reference. No coronary segments were excluded from analysis. RESULTS: The estimated pretest probability of CAD in the high (n = 105), intermediate (n = 83), and low (n = 66) groups was 87%, 53%, and 13%, respectively. The diagnostic performance of the computed tomography (CT) scan was different in the 3 subgroups. The estimated post-test probability of the presence of significant CAD after a negative CT scan was 17%, 0%, and 0% and after a positive CT scan was 96%, 88%, and 68%, respectively. CONCLUSIONS: Computed tomography coronary angiography is useful in symptomatic patients with a low or intermediate estimated pretest probability of having significant CAD, and a negative CT scan reliably rules out the presence of significant CAD. Computed tomography coronary angiography does not provide additional relevant diagnostic information in symptomatic patients with a high estimated pretest probability of CAD.     

Usefulness of 64-slice multislice computed tomography coronary angiography to assess in-stent restenosis.

OBJECTIVES: This study sought to evaluate the diagnostic accuracy of 64-slice multislice computed tomography (MSCT) coronary angiography in the follow-up of patients with previous coronary stent implantation. BACKGROUND: Recent investigations have shown increased image quality and diagnostic accuracy for noninvasive coronary angiography with 64-slice MSCT as compared with previous-generation MSCT scanners, but data on the evaluation of coronary stents are scarce. METHODS: In 182 patients (152 [84%] male, ages 58 +/- 11 years) with previous stent (> or =2.5 mm diameter) implantation (n = 192), 64-slice MSCT angiography using either a Sensation 64 (Siemens, Forchheim, Germany) or Aquilion 64 (Toshiba, Otawara, Japan) was performed. At each center, coronary stents were evaluated by 2 experienced observers and evaluated for the presence of significant (> or =50%) in-stent restenosis. Quantitative coronary angiography served as the standard of reference. RESULTS: A total of 14 (7.3%) stented segments were excluded because of poor image quality. In the interpretable stents, 20 of the 178 (11.2%) evaluated stents were significantly diseased, of which 19 were correctly detected by 64-slice MSCT. Accordingly, sensitivity, specificity, and positive and negative predictive value to identify in-stent restenosis in interpretable stents were 95.0% (95% confidence interval [CI] 85% to 100%), 93.0% (95% CI 90% to 97%), 63.3% (95% CI 46% to 81%), and 99.3% (95% CI 98% to 100%), respectively. CONCLUSIONS: In-stent restenosis can be evaluated with 64-slice MSCT with good diagnostic accuracy. In particular, a high negative predictive value of 99% was observed, indicating that 64-slice MSCT may be most valuable as a noninvasive method of excluding in-stent restenosis.     

Comparison of diagnostic accuracy of 64-slice computed tomography coronary angiography in women versus men with angina pectoris

We compared the diagnostic accuracy of 64-slice computed tomographic (CT) coronary angiography to detect significant coronary artery disease (CAD) in women and men. The 64-slice CT coronary angiography was performed in 402 symptomatic patients, 123 women and 279 men, with CAD prevalence of 51% and 68%, respectively. Significant CAD, defined as > or =50% coronary stenosis on quantitative coronary angiography, was evaluated on a patient, vessel, and segment level. The sensitivity and negative predictive value to detect significant CAD was very good, both for women and men (100% vs 99%, p = NS; 100% vs 98%, p = NS), whereas diagnostic accuracy (88% vs 96%; p <0.01), specificity (75% vs 90%, p <0.05), and positive predictive value (81% vs 95%, p <0.001) were lower in women. The per-segment analysis demonstrated lower sensitivity in women compared with men (82% vs 93%, p <0.001). The sensitivity in women did not show a difference in proximal and midsegments, but was significantly lower in distal segments (56% vs 85%, p <0.05) and side branches (54% vs 89%, p <0.001). In conclusion, CT coronary angiography reliably rules out the presence of obstructive CAD in both men and women. Specificity and positive predictive value of CT coronary angiography were lower in women. The sensitivity to detect stenosis in small coronary branches was lower in women compared with men.     

Diagnostic performance of 64-slice computed tomography coronary angiography to detect significant coronary artery stenosis

OBJECTIVE: We aimed to determine the diagnostic accuracy of 64-slice multi-slice computed tomography (MSCT) to detect significant coronary artery stenosis with comparison to conventional coronary angiography (CCA). METHODS: In 100 patients (70 men, average age 58 +/- 10 years and age range 31-75 years) scheduled to have conventional coronary angiography, MSCT was performed before catheterization (within 2 months). All patients were in sinus rhythm, able to hold breath for 15 seconds, and had serum creatinine levels < 1.5 mg/dl. MSCT scans were analysed by a radiologist and a cardiologist. Sensitivity, specificity, positive and negative predictive values for the detection of significant stenoses by MSCT in comparison with CCA were calculated on patient, vessel, and segmental bases. RESULTS: 64-slice computed tomography is able to detect significant coronary artery stenosis on a segmental basis with a sensitivity of 88% and specificity of 99% when compared with CCA. All patients with significantly stenotic coronary artery disease are correctly diagnosed. The presence of significant stenosis was correctly diagnosed by MSCT in 126 of 144 segments. Twelve non-significant lesions on CCA were overestimated by MSCT. On vessel-based analysis, the sensitivity and specificity of MSCT for detecting significant stenosis were 91% and 97%, respectively. CONCLUSION: Our results indicate that 64-slice computed coronary angiography is a reliable diagnostic modality for the detection of significant coronary artery stenosis in patients with sinus rhythm and scheduled to have CCA, but still has limitations of diagnostic performance on a per-segment and per-vessel basis.     

Impact of coronary calcium score on diagnostic accuracy of multislice computed tomography coronary angiography for detection of coronary artery disease.

BACKGROUND: The impact of the coronary calcium score on the diagnostic accuracy of multislice computed tomography (MSCT) to detect obstructive coronary stenoses remains controversial. METHODS AND RESULTS: We examined 41 patients (mean Agatston score, 340 +/- 530 [range, 0-2546]) with coronary artery disease with 16-slice MSCT and 60 patients (mean Agatston score, 446 +/- 877 [range, 0-6264]) with 64-slice MSCT. MSCT scans were analyzed with invasive coronary angiography (CA) as the standard of reference. Lesions with luminal narrowing of 50% or greater were considered obstructive. In total, 9% and 2% of uninterpretable segments were excluded from analysis in patients examined with 16- and 64-slice MSCT, respectively. On a segment basis, the percentage of false-negative segments in the groups with Agatston scores of 0 to 100, 101 to 400, and greater than 400 with 16-slice MSCT were 0%, 5.3%, and 2.9% (P = .0005), respectively; other comparisons of false-positive and false-negative segments were not significant. The sensitivity and specificity on a vessel and patient basis with 16- and 64-slice MSCT were not significantly different in different calcium score groups. CONCLUSIONS: A slight impact of coronary calcium was observed on the diagnostic accuracy of 16-slice MSCT CA on a segment basis, with no significant impact on a vessel and patient basis. No significant impact of coronary calcium was observed on the diagnostic accuracy of 64-slice MSCT CA on a segment, vessel, or patient basis.     

64层螺旋CT冠状动脉成像对冠心病诊断的应用价值

目的 通过探讨64层螺旋CT冠状动脉成像(64-SCTCA)对冠心病诊断的应用价值以明确临床上适于该项检查的人群.方法 回顾性分析285例接受64-SCTCA检查、并于4周内接受冠状动脉造影(CAG)检查的冠心病疑诊患者的临床资料.依照冠心病概率Duke模型,将受检者分为冠心病低危(n=80)、中危(n=92)和高危(n=113)3组,以CAG为"金标准",判断64-SCTCA诊断冠心病的准确性以及冠状动脉钙化、不同部位血管节段等因素对诊断准确性的影响.结果 64-SCTCA诊断冠心病的敏感性、特异性、阳性预测值、阴性预测值和诊断准确指\数分别为81.2%、93.3%、68.0%、96.6%和74.5%.冠心病概率Duke模型的低危组、中危组和高危组,其冠心病检出率分别为46.3%、72.8%和82.3%;64-SCTCA在低危组诊断冠心病的敏感性及阳性预测值明显低于中危组和高危组.对于冠状动脉Agatston钙化积分＞400分组,64-SCTCA诊断冠心病的敏感性(95.0%)明显高于0～100分组和101～400分组(77.4%和77.3%,P均＜0.05),特异性(82.2%)明显低于上述两组(94.0%和95.3%,P均＜0.05).其诊断远端血管病变的敏感性、阳性预测值均明显低于近、中段血管(P均＜0.05).结论 64-SCTCA主要适用于冠心病概率Duke模型临床分层的中危人群.其诊断准确性受冠状动脉钙化、病变部位、管腔直径等因素影响.     

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。     

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冠状动脉成像判定冠状动脉狭窄的价值

目的: 探讨64层螺旋CT冠状动脉成像（MSCTCA）判定冠状动脉狭窄的临床价值。方法: 回顾性研究在我科治疗并于2周内先后行MSCTCA和冠状动脉造影（CAG）的临床拟诊冠心病患者30(男21,女9)例;年龄49～74（62±7）岁,以CAG结果为准,计算评价指标。结果: 依节段计算的MSCTCA准确性,其灵敏度、特异度分别为50%、97%。若去除38个冠脉节段由于严重钙化而影响诊断的因素,则其灵敏度、特异度分别为74%、99%。结论: MSCTCA判断冠状动脉中、重度狭窄具有较高的准确性,对诊断冠心病尤其对筛选冠心病而言有较好的前景,但严重钙化病变影响冠状动脉狭窄程度的判断。     

Diagnostic value of CT angiography in coronary arteries stenosis detection

BACKGROUND: Noninvasive imaging of coronary arteries is very important. CT angiography (multislice computed tomography and electron beam computed tomography -- MSCT and EBT) is most reliable method for noninvasive coronary visualization. PURPOSE: The aim of our study was to evaluate the diagnostic value of CT angiography in coronary arteries stenoses detection in patients with coronary arteries disease (CAD). MATERIALS AND METHODS: 140 patients with CAD who underwent EBT (n=97) or 4-slice CT (n=43) coronary angiography and conventional coronary angiography as a gold standard were included in the study. RESULTS: Sensitivity and specificity of CT angiography in coronary stenoses detection (proximal and mid segments) were 86% and 97%, respectively. Positive and negative predictive values were 90% and 96%, respectively. Overall accuracy was 95%. 6.2% of coronary segments were excluded from the study because of unsatisfactory image quality. CONCLUSIONS: CT angiography is noninvasive method for coronary stenoses detection with high sensitivity and specificity. Nevertheless EBT and 4-slice CT angiography can not replace conventional coronary angiography because of lower temporal and spatial resolution, artifacts in patients with arrhythmias and huge coronary calcification.     

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.     

Diagnostic accuracy of 64-slice multislice computed tomography in the noninvasive evaluation of significant coronary artery disease

The purpose of the present study was to determine the diagnostic accuracy of current 64-slice multislice computed tomography (MSCT) in the detection of significant coronary artery disease, using conventional coronary angiography as the gold standard. In 61 patients scheduled for conventional coronary angiography, 64-slice MSCT was performed and evaluated for the presence of significant (>or=50% luminal narrowing) stenoses. One patient had to be excluded because of a heart rate>90 beats/min during data acquisition. In the remaining 60 patients (46 men, 14 women; average age 60+/-11 years), 854 segments were available for evaluation. Of these segments 842 (99%) were of sufficient image quality. Conventional coronary angiography identified 73 lesions, of which 62 were detected by MSCT. The corresponding sensitivity and specificity were 85% and 97%, respectively. On a patient-per-patient analysis, sensitivity, specificity, and positive and negative predictive values were 94%, 97%, 97%, and 93%, respectively. In conclusion, the present study confirms that 64-slice MSCT enables the accurate and noninvasive evaluation of significant coronary artery stenoses.     

64排螺旋CT冠脉成像与冠脉造影对冠心病诊断的比较

目的：探讨64排螺旋CT冠脉成像对冠心病的诊断价值。方法：以冠脉造影（CAG）结果为金指标，采用64排螺旋CT对100例疑诊冠心病患者的冠脉主干及主要分支400节段进行重建和分析，评价其诊断冠心病的灵敏性和特异性。结果：64排螺旋CT能清晰显示冠脉主干及分支狭窄、钙化、开口起源异常及桥血管病变，对冠脉狭窄性病变的诊断准确性高，诊断冠脉病变的灵敏度96.37％，特异度96．14％，阳性预测值95．88％，阴性预测值96．6％。但对慢性闭塞性病变诊断性的准确率稍差，灵敏度50％，特异度96．77％，阳性预测值62．5％，阴性预测值94．73％。结论：64排螺旋CT冠脉成像对冠脉狭窄病变、桥血管、心肌桥、支架管腔均显影良好，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、搭桥术后随访手段。     

Improved diagnostic accuracy with 16-row multi-slice computed tomography coronary angiography

OBJECTIVES: We sought to compare the diagnostic value of multi-slice computed tomography (MSCT) coronary angiography (CA) to detect significant stenoses (> or =50% lumen diameter reduction) with that of invasive CA. BACKGROUND: The latest 16-row MSCT scanner has a faster rotation time (375 ms) and permits scanning with a higher X-ray tube current (500 to 600 mA) during MSCT CA when compared with previous scanners. METHODS: We studied 51 patients (37 men, mean age 58.9 +/- 10.0 years) with stable angina or atypical chest pain. Patients with pre-scan heart rates > or =70 beats/min received oral beta-blockade. The heart was scanned after intravenous injection of 100 ml contrast (iodine content, 400 mg/ml). Mean scan time was 18.9 +/- 1.0 s. The MSCT scans were analyzed by two observers unaware of the results of invasive angiography, and all available coronary branches > or =2 mm were included. RESULTS: Invasive CA demonstrated normal arteries in 16% (8 of 51), non-significant disease in 21% (11 of 51), single-vessel disease in 37% (19 of 51), and multi-vessel disease in 26% (13 of 51) of patients. There were 64 significant lesions. Sensitivity, specificity, and positive and negative predictive values for detection of significant lesions on a segment-based analysis were 95% (61 of 64, 95% confidence interval [CI] 86 to 99), 98% (537 of 546, 95% CI 96 to 99), 87% (61 of 70, 95% CI 76 to 98), and 99% (537 of 540, 95% CI 98 to 99), respectively. All patients with angiographically normal coronary arteries or significant lesions were correctly identified. Three of 11 patients with <50% lesions were incorrectly classified as having single-vessel disease. CONCLUSIONS: The 16-row MSCT CA reliably detects significant coronary stenoses in patients with atypical chest pain or stable angina pectoris.     

Non-invasive detection of coronary artery disease in patients with left bundle branch block using 64-slice computed tomography.

OBJECTIVES: The goal of this study was to evaluate the diagnostic accuracy of 64-slice computed tomography (CT) to identify coronary artery disease (CAD) in patients with complete left bundle branch block (LBBB). BACKGROUND: Left bundle branch block increases risk of cardiac mortality, and prognosis is primarily determined by the underlying coronary disease. Non-invasive stress tests have limited performance, and conventional coronary angiography (CCA) is usually required. METHODS: Sixty-six consecutive patients with complete LBBB and sinus rhythm admitted for CCA were enrolled. Computed tomography was performed 3 +/- 3.9 days before CCA. The accuracy of 64-slice CT to detect significant stenosis (>50% lumen narrowing) was compared with quantitative coronary angiography. All segments were analyzed regardless of image quality from coronary calcification or motion artifacts. Results were analyzed by patient and by coronary segment (990) using the American Heart Association 15-segment model. RESULTS: Lower heart rates were associated with improved image quality. Computed tomography correctly identified 35 of 37 (95%) patients without significant stenosis and 28 of 29 (97%) patients with significant stenosis on CCA. Computed tomography correctly assessed 68 of 94 (72%) significant stenosis. Overall, accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of 64-slice CT for identifying CAD by patient was 95%, 97%, 95%, 93%, and 97%, respectively, and by segment was 97%, 72%, 99%, 91%, and 97%, respectively. CONCLUSIONS: In a routine clinical practice, 64-slice CT detects with excellent accuracy a significant CAD in patients with complete LBBB. A normal CT in this clinical setting is a robust tool to act as a filter and avoid invasive diagnostic procedures.     

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。     

Acute myocardial infarction early viability assessment by 64-slice computed tomography immediately after coronary angiography: comparison with low-dose dobutamine echocardiography.

OBJECTIVES: Early evaluation of myocardial viability in acute myocardial infarction is useful to guide therapy. Therefore, we assessed 64-slice computed tomography (CT) immediately after coronary angiography in this setting. BACKGROUND: Recent preliminary studies have shown the promising usefulness of late hyperenhancement multislice computed tomography (MSCT) for non-viability assessment. METHODS: Thirty-six patients admitted for a first acute myocardial infarction had a coronary angiogram early after admission followed by 64-slice CT without iodine reinjection. The 16 segments of the left ventricle depicted by the American Society of Echocardiography were graded: no, subendocardial, or transmural hyperenhancement. No or subendocardial hyperenhancement were expected to reflect viability. Two to 4 weeks later, the same segments' contractility was evaluated at rest. Low-dose dobutamine echocardiography was performed in case of akinetic segment at rest. RESULTS: Mean delay between coronary angiography and MSCT was 24 +/- 11 min (range 7 to 51 min). We compared 576 segments evaluated by each method. Agreement was noted for 560 segments (97%) and disagreement for 16 segments (3%). Thus, 64-slice CT after coronary angiography for an acute myocardial infarction had 98% sensitivity, 94% specificity, 97% accuracy, and 99% positive and 79% negative predictive values for detecting viable myocardial segments at a very early stage of an acute myocardial infarction. On a per-patient analysis, sensitivity, specificity, accuracy, and positive and negative predictive values were 92%, 100%, 94%, and 100% and 85%, respectively. CONCLUSIONS: A 64-slice CT after coronary angiography for an acute myocardial infarction is a promising method for early evaluation of viable myocardium.     

64层CT与血管内超声对冠状动脉粥样斑块的定性和定量评估的对照研究

目的 对照血管内超声（intravascular ultrasound,IVUS）评价64层CT对冠状动脉粥样斑块的定性检测和定量分析。方法 2005年7月至10月连续纳入12例拟行PCI的稳定性心绞痛患者进行研究。所有患者术前接受64层CT的冠状动脉成像,术中行三支冠状动脉（左前降支、回旋支和右冠状动脉）的IVUS检查。结果 共对31支血管（左前降支12支,回旋支10支,右冠状动脉9支）,88个节段进行了64层CT和IVUS的对比检查,其中64层CT可评价节段为68个。在IVUS检测到的51个有斑块节段中,64层CT检测出47个（敏感性92％）,在17个IVUS判断为无斑块的节段中,64层CT判断16个为无斑块（特异性94％）。64层CT测量的斑块面积和IVUS测量的斑块面积相关（r=0．53,P〈0．01）,但是高估了斑块面积[（9．09±3．89）mm。比（6．80±2．81）mm^2,P〈0．01]。64层CT在43个IVUS测定的低回声成分中检出30个为低密度成分,平均CT值67．39HU。结论 冠状动脉无严重钙化时,64层CT可准确检测冠状动脉近中段粥样斑块。64层CT测量的斑块面积虽然和IVUS测量结果相关,但准确测量受限。     

Accuracy of 64-slice computed tomography for the preoperative detection of coronary artery disease in patients with chronic aortic regurgitation

We studied the diagnostic accuracy of 64-slice computed tomography for the diagnosis of significant coronary artery disease (CAD) compared with conventional coronary angiography (CA) in patients with chronic aortic regurgitation (AR) referred for elective aortic valve surgery. Fifty consecutive patients with chronic AR (38 men, mean age 54 +/- 14 years) scheduled for valve surgery underwent 64-slice computed tomographic (CT) coronary angiography and CA. Significant stenosis was defined as a luminal diameter decrease >50%. Mean heart rate during CT scanning was 65.5 +/- 7.4 beats/min. Mean Agatston score was 136 +/- 278 (range 0 to 1207); prevalence of significant CAD in the study population was 26% (13 of 50 patients). Thirteen of 742 segments (1.8%) in 3 patients were considered nondiagnostic with computed tomography because of motion artifacts (n = 9) or calcium (n = 4). In a patient-based analysis taking nonevaluative segments as falsely positive, sensitivity, specificity, and positive and negative predictive values of computed tomography were 100%, 95%, 87%, and 100%, respectively. Preoperative CA could have been avoided in 70% of patients (35 of 50), CA would have been performed to confirm the CT diagnosis in 26% (13 of 50), and unnecessary CA would have been performed in 4% (2 of 50) on the basis of false-positive CT ratings. In conclusion, 64-slice CT coronary angiography provides high diagnostic accuracy for diagnosing significant CAD in patients with chronic AR and may be used as a filter test before valve surgery to decide whether CA should be performed.     

Do risk factors influence the diagnostic accuracy of noninvasive coronary angiography with multislice computed tomography?

BACKGROUND: Multislice computed tomography (MSCT) is a relatively new noninvasive imaging modality in the evaluation of patients with suspected coronary artery disease (CAD). Whether diagnostic accuracy is influenced by gender or risk factors for CAD is currently unknown and was evaluated in this study. METHODS AND RESULTS: In 197 patients (171 men and 26 women; mean age, 60 +/- 11 years) 16-slice MSCT was performed and compared with invasive coronary angiography at 2 different centers (Leiden and Rotterdam, The Netherlands). Diagnostic accuracy for the detection of 50% luminal narrowing or greater was calculated for all patients combined, as well as for patients with known versus suspected CAD. In addition, diagnostic accuracy was determined in men versus women and in different subsets of patients based on the presence of risk factors for CAD including hypertension, type 2 diabetes mellitus, hypercholesterolemia, and obesity. Only segments with a diameter of 2.0 mm or greater were evaluated, whereas smaller segments and stents were excluded from the analysis. Overall, a sensitivity and specificity of 99% and 86%, respectively, on a patient level were demonstrated, with corresponding positive and negative predictive values of 95% and 96%, respectively. Similar values were observed in the different subsets of patients, with no statistical differences. CONCLUSION: These findings confirm the high diagnostic accuracy of MSCT, regardless of gender or risk factors.