Impact of luminal density on plaque classification by CT coronary angiography

Non-invasive coronary CT angiography (CCTA) has the potential to characterize the composition of non-calcified coronary plaques. CT-density values characterized by Hounsfield Units (HU) may classify non-calcified plaques as fibrous or lipid-rich, but the luminal density caused by the applied contrast material influences HU in the plaques in vitro. The influence of luminal density on HU in non-calcified plaques in vivo is unknown. Hence the purpose of this study was to test whether plaque characterization by CCTA in vivo depends on luminal density. Two CCTA-scans using two different contrast protocols were obtained from 14 male patients with coronary artery disease. The two contrast protocols applied resulted in high and low luminal density. Eleven non- calcified and 13 calcified plaques were identified and confirmed by intravascular ultrasound. Luminal attenuation differed with the two contrast protocols; 326[284;367] vs. 118[103;134] HU (P < 0.00001). In non-calcified plaques mean HU-values was lower 48[28;69] vs. 11[−4;25] HU (P = 0.004) with the low density protocol. As a consequence three out of eleven non-calcified plaques (27%) were reclassified from fibrous (high) to lipid rich (low). For calcified plaques a less pronounced but still significant difference in HU-values was found with the low luminal density. 770[622;919] vs. 675[496;855] HU (P = 0.02). Conclusion: Non-calcified plaques can be identified and classified by CCTA. However, the luminal density affects the absolute HU of both non-calcified and calcified plaques. Characterization and classification of non-calcified plaques by absolute CT values therefore requires standardization of contrast protocols.     

The potential of RF backscattered IVUS data and multidetector-row computed tomography images for tissue characterization of human coronary atherosclerotic plaques

The aim is to compare virtual histology which uses spectral analysis of backscattered intravascular ultrasound (VH–IVUS) and multidetector-row computed tomography (MDCT) for the characterization of coronary atherosclerotic plaques obtained by directional coronary atherectomy (DCA). We performed DCA in 15 de novo native coronary stenotic lesions (15 patients) and selected one or two segments within the plaque from each patient (total 29 segments). Then, we evaluated the accuracy of the VH–IVUS findings in 50 sites among the 29 segments compared with the histopathology findings. MDCT was performed in all patients before percutanous coronary intervention (PCI), and CT density values were measured. VH–IVUS data analysis correlated well with histopathological examination (predictive accuracy: 66.7% for fibrous, 100% for fibro-fatty, 100% for necrotic core, and 100% for dense calcium regions, respectively). In addition, CT density values between fibrous and fibro-fatty plaques classified by histopathology were 100.0 ± 26.0 HU versus 110.4 ± 67.9 HU, there were no difference among them (P = 0.594). These findings indicated that the validation of plaque characteristics using VH–IVUS correlates well with histopathology. While tissue characterization using CT density could be difficult to distinguish between fibro-fatty and fibrous tissue.     

How reliable are 40 MHz IVUS and 64-slice MDCT in characterizing coronary plaque composition? An ex vivo study with histopathological comparison

The present study investigated whether IVUS could serve as a reliable reference in validating MDCT characterization of coronary plaque against a histological gold standard. Twenty-one specimens were postmortem human coronary arteries. Coronary cross-sections were imaged by 40 MHz IVUS and by 64-slice MDCT and characterized histologically as presenting calcified, fibrous or lipid-rich plaques. Plaque composition was analyzed visually and intra-plaque MDCT attenuation was measured in Hounsfield Units (HU). 83 atherosclerotic plaques were identified. IVUS failed to characterize calcified plaque accurately, with a positive predictive value (ppv) of 75% versus 100% for MDCT. Lipid-rich plaque was even less accurately characterized, with ppv of 60 and 68% for IVUS and MDCT respectively. Mean MDCT attenuation was 966 ± 473 HU for calcified plaque, 83 ± 35 HU for fibrous plaque and 70.92 HU ± 41 HU for lipid-rich plaque. No significant difference in mean MDCT attenuation was found between fibrous and lipid-rich plaques (P = 0.276). In vivo validation of MDCT against an IVUS reference thus appears to be an unsuitable and unreliable approach: 40 MHz IVUS suffers from acoustic ambiguities in plaque characterization, and 64-slice MDCT fails to analyze plaque morphology and components accurately.     

Quantification of atherosclerotic coronary plaque components by submillimeter computed tomography

Background: Although several investigations have shown that multi-detecor row computed tomography (MDCT) of the coronary arteries can detect noncalcified atherosclerotic plaque, it has remained unresolved if the method also determines features of a rupture-prone plaque. We set out to correlate the size of atherosclerotic plaque components with cardiac MDCT with histology. Methods and results: In 30 autopsy cases, hearts were isolated, coronary arteries filled with contrast agent, and depicted with a clinical 16-row detector CT with a slice thickness of 0.63 mm. Transections of the three main coronary arteries were reconstructed and compared with histopathologic sections using light microscopy. MDCT measurements of total plaque area (r = 0.73, P < 0.0001) and calcified plaque area (r = 0.83, P < 0.0001) correlated well with histopathology, while measurements of non-calcified plaque area (r = 0.53, P < 0.0001) and lipid core size (r = 0.43; P < 0.0001) correlated less well. MDCT overestimated all plaque areas except lipid core size, which was underestimated. Conclusions: Coronary CT provides an accurate and reproducible method for the quantitative assessment of total plaque and calcified plaque areas. However, the method is less accurate for the quantification of non-calcified plaque area and lipid core size, which is ascribed to limited spatial and contrast resolution. With the present technique, the detection of vulnerable plaques by MDCT remains uncertain.     

Characteristics of coronary plaques before angiographic progression determined by Multi-Slice CT

The aim of the present study was to characterize coronary plaques by Multi-Slice Computed Tomography (Siemens sensation 16, Forcheim, Germany) before significant angiographic progression occurred and to compare them to non-progressing lesions. The MSCT-morphology of coronary plaques leading to a rapid angiographic disease progression is not yet studied. In a series of 68 patients who were scheduled for surveillance angiography 6 months later, MSCT-angiography was done shortly after the baseline catheterisation-procedure. After surveillance angiography rapid progressive lesions with an increase of the stenosis severity of >20% were identified and analysed on the baseline MSCT-scan and were compared to non-progressing lesions. Six months after coronary stenting we observed significant progression of de novo stenoses in 10/438 coronary segments. The progression of four lesions lead to angina pectoris symptoms and the remaining six lesions progressed silently. Analysis of the lesion morphology by MSCT revealed that 5/10 (50%) progressing lesions were non-calcified 3/10 (30%) were predominantly non-calcified and 2/10 (20%) were mainly calcified on the baseline MSCT-scan. In the 428 segments without disease progression atherosclerotic lesions were found in 225 segments on MSCT. Non-calcified plaques were identified in 46 (20%), predominantly non-calcified lesions in 58 (26%) and predominantly calcified lesions in 121 (54%) segments. The average number of diseased coronary segments between patients with and without lesion progression was not significantly different between progressors and non-progressors with a higher prevalence of non-calcified segments in the progressor group (1.1 vs. 0.63). Rapid progression of the angiographic stenosis severity during a 6 months period occurs most frequently in coronary segments revealing non-calcified or predominantly non-calcified plaques as determined by MSCT, whereas lesion progression is rare in predominantly calcified segments. This represents first evidence that non-calcified lesions may be involved in the process of plaque rupture.     

Reproducibility of coronary plaque detection and characterization using low radiation dose coronary computed tomographic angiography in patients with intermediate likelihood of coronary artery disease (ReSCAN study)

The purpose of this study is to evaluate the interscan, interobserver and intraobserver agreement for coronary plaque detection, and characterization using low radiation dose high-pitch spiral acquisition coronary CT angiography (CTA). Two experienced observers independently evaluated coronary CTA datasets from 50 consecutive patients undergoing two 128-slice dual source CT scans within 12 days. Mean (±SD) estimated radiation exposure was 1.5 ± 0.2 mSv per scan. Observers recorded the presence and characterization of coronary plaques as non-calcified or calcified. A "segment involvement score" (SIS) was computed by summing the numbers of segments with any coronary plaque per patient. Reproducibility was assessed using kappa (κ) statistics, paired t test and Bland-Altman analyses. Interscan, interobserver, and intraobserver agreement (κ-values) for detection of any or calcified plaques were 83-94% (κ-values 0.57-0.85), and 67-84% (0.31-0.67) for non-calcified plaques on a patient level. No significant difference was observed in mean interscan or interobserver SIS. Mean (95% CI) intraobserver SIS difference was -0.88 (-1.25; -0.51), P < 0.001, with limits of agreement from -4.7 to 2.9. Low radiation dose high-pitch coronary CTA permits detection of any or calcified plaques with high interscan, interobserver, intraobserver agreement. However, variability for the detection of non-calcified plaque is substantial.     

冠状动脉CT血管成像对无症状人群非钙化性斑块危险因素的初步研究

目的利用CT冠状动脉成像,对无症状人群非钙化性斑块发生的相关危险因素进行系统分析,为临床早期预防急性冠状动脉综合征提供参考依据。方法对2008年11月至2009年12月行320排冠状动脉CT成像的292例无症状患者行回顾性分析。非钙化斑块定义为局部管壁高于周围组织密度但低于成像剂密度的结构。根据患者临床资料,参照Morise评分标准,患者分为患有冠状动脉明显狭窄性冠心病低、中、高危险人群。采用Logistic回归对非钙化性斑块与危险因素及低、中、高危险度的关系进行分析。结果 292例患者中,112例患者(38.4%)发现非钙化性斑块,83例(74.1%)导致管腔1级狭窄,13例(11.6%)为2级狭窄,10例(8.9%)为3级狭窄,6例(5.4%)为4级狭窄。利用Morise评分分级方法虽然对管腔狭窄程度有较好预测性,但对于非钙化斑块存在与否的预测能力较差。根据Logistic回归分析,年龄、性别、雌激素状态、血压、吸烟史、家族史以及是否肥胖与非钙化性斑块无明显关系,而高血脂(P=0.008)与糖尿病(P<0.001)明显影响非钙化性斑块的发生率。结论糖尿病与高血脂为非钙化性斑块的两大危险因素。对糖尿病与高血脂患者,建议CT冠状动脉成像对非钙化性斑块进行筛查,对患者急性冠状动脉综合征危险度进行评估,指导临床治疗并预防急性冠状动脉综合征的发生。     

离体冠状动脉粥样硬化钙化斑块CT、MRI及病理对照

目的 评价64层CT和1.5T MR扫描仪在显示离体冠状动脉粥样硬化钙化斑块成分的作用.方法 对12具尸体心脏行冠状动脉前降支近段CT及MR检查,并与病理学相对照.分析钙化斑块的CT值及MRI的信号强度.结果 43个CT、MRI所示的钙化斑块层面可与相应的组织学层面相对应.钙化成分为主的斑块CT值平均为1065 HU.MRI示钙化斑块在各个序列均表现为低信号,48.84%的钙化层面内有稍高信号,组织切片示脂质成分.58.14%的钙化斑块内有新生血管或炎细胞浸润.结论 CT、MRI都可以显示冠状动脉粥样硬化钙化斑块的特点,但显示钙化斑块内的脂质成分,MRI优于CT.     

Variation in atherosclerotic plaque composition according to increasing coronary artery calcium scores on computed tomography angiography

Increasing coronary artery calcium scores (CACS) are independently associated with cardiac events. Recent advents in coronary computed tomography angiography (CCTA) have allowed us to better characterize individual plaque. Currently, it is unknown if higher CACS are likely to be associated with more calcified or mixed and heterogeneous plaque burden on CCTA. The study population consisted of 1,043 South Korean asymptomatic subjects (49 ± 10 years, 62% men) who underwent CCTA (64-slice MDCT). Plaques were classified on contrast-enhanced CCTA as non-calcified, mixed, and calcified on a per-segment basis according to the modified American Heart Association classification. The majority of the study participants had no coronary calcification (n = 866, 83%), whereas CACS> 0 was observed in 177 participants (17%). Only 40 (5%) participants in absence of CACS had exclusively non-calcified plaque, whereas 10 (1.2%) had significant coronary artery disease. With increasing CACS, study participants were more likely to have exclusively mixed or combination atherosclerotic plaques (P = 0.001). Among individuals with CACS 1–10, the prevalence of at least two coronary segments with mixed plaques was 4%, increasing up to 18 and 41% with CACS of 11–100 and >100. The respective prevalence of ≥2 coronary segments (calcified plaques) with increasing CACS were 6%, 16 and 26% (P = 0.01) and of non-calcified plaques were 6%, 6 and 11% (P = 0.71). In multivariable adjusted analyses, those with CACS >100 were 7.17 times (95% CI: 1.36–37.68) more likely to have ≥2 coronary segments with calcified plaque comparing with CACS 1–10. On the other hand the respective risk was higher for presence of ≥2 segments with mixed plaques (odds ratio: 15.81, 95% CI: 3.14–79.58). Absence of CAC is associated with a negligible presence of any atherosclerotic disease as detected by CCTA in asymptomatic population. A higher CACS is more likely to be associated with heterogeneous coronary plaque (combination of calcified, non-calcified, and mixed plaques), and appears to be more strongly associated with a higher burden of mixed plaque.     

双源螺旋CT与血管内超声对冠状动脉斑块和血管重塑的比较

目的以血管内超声(IVUS)为标准,评价双源螺旋CT(DSCT)对冠状动脉斑块、血管重塑的临床应用价值。方法入选拟诊为冠心病的17例患者,分别行DSCT和IVUS检查,以10mm为一评估节段,分别评估每个有效节段斑块的性质和CT值,并测定管腔面积、斑块面积、斑块负荷和血管重塑指数。结果在21支冠状动脉的114段可评估的冠状动脉节段中,DSCT对斑块诊断的敏感性为88.10%(37/42),特异性为95.83%(69/72),阳性预测值为92.50%(37/40),阴性预测值为93.2%(69/74)。DSCT和IVUS对管腔面积、斑块面积和斑块负荷的测量值分别为:(6.79±3.29)mm~2比(6.80±2.79)mm~2;(8.89±5.44)mm~2比(8.24±3.05)mm~2;(55.26±13.32)%比(55.09±9.42)%(P0.05)。相关系数分别为0.81,0.75和0.51(P0.01)。以IVUS结果将斑块分为脂质斑块、纤维斑块和钙化斑块,分别测得CT值为(54.50±5.59)HU(117.90±13.79),HU(780.18±134.73)HU(P0.01)。两两比较发现脂质斑块和纤维斑块的CT值无显著性差异(P=0.44)。DSCT与IVUS对血管重塑指数相关性检验,r=0.38,P0.05。结论与IVUS比较,DSCT是一种能有效检测冠状动脉粥样斑块的无创检查方法,能准确的评估冠脉临界病变的管腔面积、斑块面积及斑块负荷,能有效评估冠状动脉钙化和非钙化成分,对血管重塑性的评估与IVUS测量结果相关。     

Non-calcified coronary atherosclerotic plaque visualization on CT: effects of contrast-enhancement and lipid-content fractions

Computed tomography (CT) may characterize lipid-rich and presumably rupture-prone non-calcified coronary atherosclerotic plaque based on its Hounsfield-Unit (HU), but still inconclusively. This study aimed to evaluate factors influencing the HU-value of non-calcified plaque using software simulation. Several realistic virtual plaqueburdened coronary phantoms were constructed at 5 μm resolution. CT scanning was simulated with settings resembling a 64-row multi-detector CT (64-MDCT) and reconstructed at 64-MDCT (0.4 mm) and MicroCT (48 μm) resolutions. Influences of lumen contrast-enhancement, stenosis-grades, and plaque compositions on plaque visualization were analyzed. Lumen contrast-enhancement and mean plaque HU-value were positively correlated (R² > 0.92), with approximately the same slopes for all plaque compositions. Percentage lipid-content and mean plaque HU-value were negatively correlated (R² > 0.98). Stenosis-grade and noise had minimal influence on the correlations. Influence of lumen contrast-enhancement on plaque HU-value was following a specific exponentially declining pattern (y = Ae^?λx + c) from the lumen border until 2-pixel radius. Outside 2-pixel radius, plaque HU-values deviated maximally 5 HU from non-contrast-enhanced reference. Thus, to avoid lumen contrast-enhancement influence, plaques should be measured outside 2-pixel radius from the lumen border. Based on the patterns found, a lumen influence correction algorithm may be developed. HU-based plaque percentage lipid-content determination might serve as an alternative plaque characterization method. However, its applicability is still hindered by many inherent limitations.     

心包脂肪组织体积与冠状动脉斑块组成的相关性研究

目的：本研究的目的是评估心包脂肪组织（PAT）体积与320排冠状动脉CT造影（CCTA）动脉硬化斑块组成的关系。方法本研究纳入1597例因可疑冠心病而接受320排 CCTA 检查的患者（男1090例,女507例,年龄35～71岁）。其中382例发现存在动脉斑块。我们比较了冠心病和斑块组成[存在斑块、钙化斑块（CP）、非钙化斑块（NCP）、混合斑块（MP）、多支病变和梗阻性狭窄]与无冠心病者的PAT体积。结果单因素分析显示存在CP、NCP、MP及多支血管病变者的PAT体积大于无斑块者[分别为（211.4±93.6）cm3、（233.2±95.0）cm3、（257.3±82.1）cm3及（261.5±101.7）cm3 vs.（173.7±98.1） cm3,P值分别为0.012、0.008、0.004及0.002]。存在梗阻性狭窄者的PAT体积明显大于无斑块者[（279.2±99.81）cm3 vs.（173.7±98.1）cm3,P＜0.001]。在多因素Cox比例风险回归模型分析中,只有MP、多支血管病变和梗阻性狭窄者的PAT体积明显大于无斑块者（P＜0.001）。结论存在冠状动脉斑块、CP、NCP、MP、多支血管病变和梗阻性狭窄患者的PAT体积大于无斑块者,PAT体积是冠心病重要的危险因素之一。     

斑块定量参数及冠周脂肪衰减指数对FFR-CT进展的影响

目的 探讨基于冠状动脉CT血管成像(CCTA)的基线斑块定量参数和冠脉周围脂肪衰减指数(FAI)对CT血流储备分数(FFR-CT)进展的影响.方法 回顾性分析行两次CCTA检查的259例患者资料.分析斑块的定量参数,并测量冠周FAI和FFR-CT.第一次CCTA选定斑块远段FFR-CT≥0.8,第二次FFR-CT<0....     

The presence,characterization and prognosis of coronary plaques among patients with zero coronary calcium scores

Patients with coronary artery calcium (CAC) scores of zero are generally considered not to have atherosclerosis. Recent studies involving computed tomography coronary angiography (CTCA) challenge this assumption. This goal of the present study is to assess the frequency, morphology, location, and the prognosis of patients with plaque detected on CTCA and zero CAC. 1,119 patients (51 ± 12 years, 52% male) with a zero CAC score during CTCA study were retrospectively identified. The CTCA studies were assessed for the presence, morphology, location and severity of all coronary plaques. All-cause mortality was assessed. The prevalence of coronary plaque was 13% (147 patients). Among the 212 plaques identified 154 (73%) were non-calcified, 28 (13%) were calcified, and 30 (14%) were of mixed morphology. Notably, ≥70% stenosis was noted among only 0.4% of all patients. ROC analysis revealed that coronary artery disease risk factors did not add to the prediction of plaque among our patients. Over a mean follow-up of 2.5 ± 0.6 years there were 4 deaths (0.4%), all in patients without coronary plaque on CTCA. The presence of coronary plaque is not uncommon among patients with zero CAC scores. These plaques were rarely associated with hemodynamically significant stenoses and were associated with an excellent prognosis. Clinical factors do not appear to be useful in predicting which patients with zero CAC scores have undetected coronary plaque.     

Coronary plaque imaging and characterization by CT

Multi-slice spiral CT (MDCT) is a noninvasive modality for visualization and evaluation of atherosclerosis in vivo in different arterial beds. Rapid technical advances led to a significant improvement of the diagnostic accuracy of coronary MDCT angiography. The most popular clinical application of MDCT with the best scientific evidence is the noninvasive detection and quantification of coronary calcifications. In particular, the concept of coronary age by evaluating an individual’s biological age (rather than chronological age) is attractive and currently under scientific evaluation. Additionally, when evaluating contrast-enhanced coronary arteries, different stages of atherosclerosis can be visualized. It could be shown by comparative studies with intracoronary ultrasound that echogenicity corresponds well with the density measured within atherosclerotic plaques expressed in Hounsfield units using MDCT. Continuously improving and still under development, the potential of MDCT to evaluate plaque composition and plaque volumes noninvasively in vivo is promising.     

冠状动脉斑块相关参数与血管周围脂肪组织参数的关系

目的 观察冠状动脉斑块相关参数与血管周围脂肪组织(PVAT)参数——冠周脂肪衰减指数(pFAI)及冠周脂肪体素总体积(pFV)的关系。方法 回顾性分析187例因疑诊冠状动脉疾病而接受冠状动脉CT血管造影(CCTA)患者，共218支冠状动脉分支存在斑块。基于CCTA评估斑块相关参数，包括斑块性质(钙化性斑块、混合性斑块及非钙化性斑块)、是否易损斑块、斑块长度和负荷、血管重构状态(无重构、负性重构及正性重构)及血管狭窄程度(轻/中/重度),分析上述参数与pFAI及pFV的相关性。结果 荷混合性及非钙化性斑块血管的PVAT的pFAI高于荷钙化性斑块血管，荷易损斑块血管PVAT的pFAI高于荷非易损斑块血管，pFV与之相反(P均<0.05)。无重构血管PVAT的pFAI低于、pFV高于负性重构及正性重构血管(P均<0.001)。重度狭窄血管PVAT的pFAI高于轻、中度狭窄血管(P均<0.05)。斑块长度及负荷均与pFAI呈线性正相关，与pFV呈线性负相关(P均<0.001)。结论 冠状动脉斑块相关参数均与其pFAI和(或)pFV相关。     

冠脉CT血管成像斑块定量参数预测冠心病患者心肌缺血事件的临床价值

  目的  分析冠脉CT血管成像（CTA）斑块定量参数预测冠心病患者心肌缺血事件的临床价值。  方法  纳入2020年1月~2022年6月256例初诊冠心病患者作为研究对象,均行冠脉CTA检查,检测斑块定量参数,根据血流储备分数检测结果将患者分为心肌缺血组和非心肌缺血组,比较两组冠脉CTA斑块定量参数,采用多元线性回归分析斑块定量参数与心肌缺血性损伤的关系,采用ROC曲线评估斑块定量参数对心肌缺血性损伤的预测价值。  结果  心肌缺血组总斑块体积、非钙化斑块体积、低密度非钙化斑块（LDNCP）体积、斑块长度、直径狭窄度均大于非心肌缺血组（P < 0.05）,钙化斑块（CP）体积及血流储备分数小于非心肌缺血组（P < 0.05）;多元线性回归分析显示,总斑块体积、LDNCP体积为冠心病患者心肌缺血的独立影响因素（P < 0.05）;ROC曲线显示,总斑块体积、LDNCP体积联合预测心肌缺血性损伤的敏感度、特异性、曲线下面积分别为94.30%、77.80%、0.948。  结论  冠脉CTA斑块定量参数变化与冠心病患者心肌缺血性损伤有关,其中总斑块体积、LDNCP体积可作为心肌缺血事件的预测指标。      

Coronary CT angiography in patients with high calcium score: evaluation of plaque characteristics and diagnostic accuracy

Our aim was to evaluate the plaque characteristics of coronary arteries related to significant stenosis with coronary CT angiography (CCTA) and to discuss the diagnostic accuracy of CCTA in patients with high calcium scores. After institutional review board approval, 110 patients (63 men; mean age: 67.1 ± 7.9 years) with Agatston scores >400 were retrospectively reviewed. Patients underwent Agatston calcium scoring and 64-slice CCTA, in addition to invasive coronary angiography (CAG). The composition (calcified, mixed, and non-calcified) and configuration (concentric, eccentric) of coronary artery plaques were analyzed on a per-segment basis by CCTA. We analyzed the differences in plaque composition and configuration between significant (≥ 50%) and non-significant (<50%) stenosis. Additionally, the diagnostic accuracy of stenosis according to plaque composition was evaluated by CCTA, using CAG as a reference method. Significant differences in plaque composition and configurations were observed between the two groups. In cases of significant stenosis, the proportions of concentric, mixed, and non-calcified plaques were significantly higher than those of eccentric and calcified plaques (P < 0.001). The sensitivity and positive predictive value of mixed (97.4, 87.6%) and non-calcified plaques (97.8, 95.7%) were significantly higher than those of calcified plaques (87.6, 67.2%). Although CCTA has limited value due to low diagnostic accuracy of calcified plaques, knowledge about the high frequencies of mixed and non-calcified plaques in significant stenosis help to make an accurate assessment of CAD with CCTA in patients with high calcium scores.     

Characterization of culprit lesions in acute coronary syndromes compared with stable angina pectoris by dual-source computed tomography

To identify the characterization of culprit lesions in acute coronary syndrome (ACS) compared with stable angina pectoris (SAP) by dual-source computed tomography (DSCT). 65 patients with ACS and 75 controls with SAP and a similar atherosclerotic risk profile were studied. Computed tomography (CT) coronary angiography was performed using a DSCT scanner before invasive catheterization. Using DSCT and quantitative coronary angiography (QCA), lesion characteristics [luminal cross-section area (L-CSA), vascular cross-section area (V-CSA), plaque area and degree of stenosis) were detected. Plaque types, mean and minimum CT density (Hounsfield Unit; HU), remodeling index, and presence of “spotty” calcifications were analyzed using DSCT. A good correlation was observed between DSCT and QCA for all lesion characteristics (P < 0.05). Culprit lesions in ACS had much larger V-CSA (20.5 ± 6.0 vs. 14.8 ± 4.8 mm²), plaque area (15.3 ± 5.0 vs. 11.1 ± 3.3 mm²) and remodeling index (1.3 ± 0.2 vs. 1.0 ± 0.4) than stable lesions in SAP (P < 0.05). The prevalence of non-calcified/calcified/mixed plaque was 30/0/35 in ACS versus 25/15/35 stable lesions in SAP (P < 0.01). The proportion of “spotty” calcified plaques was 21.5 % in culprit lesions (14 of 65) versus 1.3 % in SAP (1 of 75). The mean/minimum HU of culprit lesions was 88.6 ± 43.2/154.2 ± 98.7 in ACS versus 45.9 ± 34.7/98.2 ± 76.8 in SAP (both P < 0.01). DSCT is a feasible means of detecting coronary stenosis with good accuracy compared with QCA. Culprit lesions in ACS display a greater proportion of non-calcified material with lower CT attenuation, “spotty” calcifications and higher remodeling index compared with SAP lesions.     

血清MMP9和MPO及sCD40L识别冠状动脉斑块性质的初步研究

目的 探讨MMP9、MPO及sCD40L在识别冠状动脉斑块性质中的作用.方法 选取2008年4月至2010年1月阜外心血管病医院门诊胸痛患者118例,根据64排螺旋CT检查结果,将CT值＜130 Hu的患者入选为非钙化斑块组(71例),CT值≥130 Hu的患者入选为钙化斑块组(47例).选取90名健康体检者为对照组.采用ELISA检测血清MMP9、MPO及sCD40L水平,并比较其在各组中水平的差异.采用ROC曲线评价各标志物诊断非钙化斑块的敏感度和特异度.结果 非钙化斑块组血清MMP9、MPO、sCD40L水平分别为(762.25±368.71)、[844.10(582.00～ 1220.70)]、(9.37±3.15) μg/L,高于健康对照组的(342.70±178.53)、[426.35(283.20～592.00)]、(6.55±2.96) μg/L及钙化斑块组的(483.12±219.09)、[469.00(302.45～723.55)]、(7.24±2.86) μg/L,差异均有统计学意义(统计值分别为F =42.47,H=50.28,F=17.94,P均＜0.01).MMP9、MPO及sCD40L识别非钙化斑块的ROC曲线下面积分别为0.854、0.792、0.751,当识别非钙化斑块的临界值分别为510.13、537.82、7.05 μg/L时,其诊断敏感度分别为80％、80％和80％,特异度分别为80％、67％和55％.结论 血清MMP9、MPO和sCD40L水平有助于判断冠状动脉斑块的性质.