Aortic plaque imaging and monitoring atherosclerotic plaque interventions

The atherosclerotic process that results in coronary artery disease (CAD) is recognized to be a generalized process that may involve the entire vasculature. The association between CAD and atherosclerotic plaques in the thoracic aorta has often been reported using transesophageal echocardiography. An autopsy study showed plaques in the abdominal aorta, but not in the thoracic aorta, to be severe in patients with cardiac events. However, studies evaluating an association between abdominal aortic plaques and CAD are scarce. Recently, magnetic resonance imaging (MRI) has become a useful tool for the noninvasive evaluation of atherosclerotic plaques in both the thoracic and abdominal aortas. Plaques in the thoracic and abdominal aortas were found to be characteristically associated with hypercholesterolemia and smoking, respectively, suggesting different susceptibilities to risk factors. Because patients have various risk factors, it seems to be preferable to evaluate atherosclerosis in multiple vascular beds than in just 1 bed. Magnetic resonance imaging can evaluate atherosclerosis in multiple vascular beds in the same examination session. Complex aortic plaques, especially in the abdominal aorta, were found to be associated with myocardial infarction and complex coronary lesions, suggesting a link between aortic and coronary plaque instability. Aortic MRI may thus be useful for identifying vulnerable patients. Moreover, MRI is a powerful tool to serially evaluate plaque progression and regression. Intensive lipid-lowering therapy can regress aortic plaques, but the susceptibility to lipid lowering and the process of plaque regression may differ between the thoracic and abdominal aortic plaques.     

Plaque and structural characteristics of the descending thoracic aorta using transesophageal echocardiography

The in vivo acoustic and structural characteristics of atherosclerosis in the descending thoracic aorta have not been well delineated. We prospectively evaluated the descending thoracic aorta of 147 patients (35 women and 112 men; age, 61 +/- 14 years) who underwent clinically indicated transesophageal echocardiography. Patients with suspected disease of the aorta were excluded. Thirty-eight patients (26%) had protruding plaques (men, 25%; women, 29%). Six patients had mobile intimal densities with the mobile area ranging up to 1 cm2. As expected, aortic lumen area was decreased (plaque-free, 3.53 cm2; plaque, 3.19 cm2; p less than 0.05) and wall area was increased (plaque-free, 1.51 cm2; plaque, 1.92 cm2; p less than 0.05) in the regions of the plaque. However, total arterial area was not increased (plaque-free, 5.04 cm2; plaque, 5.09 cm2; difference not significant) in a compensatory manner as observed in other arterial beds. Plaque gray scale was less than the gray scale of plaque-free wall (plaque-free, 141.2; plaque, 122.7; p less than 0.05) when compared at the same level of the descending thoracic aorta or with a second aortic plaque-free level (plaque-free, 150.4; plaque, 122.7; p less than 0.05). Standard deviation of gray scale level was similar between plaque and normal regions. Unsuspected protruding plaques in the descending thoracic aorta occurred in one quarter of the patients referred for routine transesophageal examination. Plaques tended to have lower echogenicity and were differentiated from plaque-free walls within patients. Plaque formation did not result in increased total arterial area. These data suggest that the degree or character of compensatory atherosclerotic remodeling in the highly elastic descending thoracic aorta may differ from other arterial beds.     

经食管超声心动图检测主动脉粥样硬化斑块与冠状动脉病变严重程度的相关性研究

目的 通过经食管超声心动图检测主动脉的不同部位不同斑块性质与冠状动脉血管病变严重程度进行对比研究,寻找冠状动脉病变严重程度的预测因素.方法 对118例同时进行了经食管超声心动图及冠状动脉造影检查的患者进行对比研究.冠状动脉造影显示血管内径狭窄≥70%定义为冠状动脉病变.粥样硬化斑块厚度大于4 mm,有漂浮物形成或斑块溃疡定义为复杂斑块;其他大于2 mm并小于4 mm的斑块定义为简单斑块.根据冠状动脉病变支数将研究对象分为4组:A组(0支病变)99例,B组(1支病变)31例,C组(2支病变)8例,D组(3支病变)30例,比较各组间粥样硬化斑块的发生部位及程度特征.结果 与A组0支病变的99例相比,有血管狭窄的89例患者(包括B,C,D组)的主动脉内粥样斑块的发生率、严重度均明显增高(P＜0.05).多元回归分析显示高血压(优势比3.0,95%可信区间1.3～7.0,P=0.013)、糖尿病(优势比2.4,95%可信区间1.1～4.9,P=0.022)及主动脉斑块(优势比3.8,95%可信区间1.8～8.2,P=0.001)与冠状动脉病变发生明显相关.简单及复杂斑块均与冠状动脉病变严重度明显相关(P＜0.001).多元回归分析显示主动脉降部复杂斑块是冠状动脉病变的最强预测因子(优势比5.4.95%可信区间1.8～16.4,P=0.003).结论 主动脉内简单及复杂粥样斑块均与冠状动脉病变严重度明显相关.降主动脉复杂斑块是冠状动脉病变的最强预测因子.     

Atheromas of the thoracic aorta: A comparison of transesophageal echocardiography and breath-hold gadolinium-enhanced 3-dimensional magnetic resonance angiography.

Transesophageal echocardiography (TEE) has been the procedure of choice for identifying thoracic aortic atheromas. All patients over a 2-year period who underwent both TEE and magnetic resonance angiography of the thoracic aorta within 1 month were identified. The largest plaque in 3 aortic segments (ascending, arch, and descending) was measured. Thirty patients (16 men; 66.8 +/- 12.9 years) were studied. The mean size of the atheromas in the arch was larger as measured by TEE compared with magnetic resonance angiography (3.4 vs 1.4 mm, P =.01). However, the mean atheroma size was similar in the ascending aorta (1.9 vs 1.3 mm, P =.5) and descending aorta (3.9 vs 3.5 mm, P =.66). Of 24 aortic segments with plaques measuring >/=5 mm (with high embolic risk), 22 (92%) were seen on TEE and only 13 (54%) on magnetic resonance angiography (P =. 003). In conclusion, although both techniques are complementary, TEE does identify more high-risk plaques.     

Multimodal cardiovascular magnetic resonance quantifies regional variation in vascular structure and function in patients with coronary artery disease: Relationships with coronary disease severity

Background

Cardiovascular magnetic resonance (CMR) of the vessel wall is highly reproducible and can evaluate both changes in plaque burden and composition. It can also measure aortic compliance and endothelial function in a single integrated examination. Previous studies have focused on patients with pre-identified carotid atheroma. We define these vascular parameters in patients presenting with coronary artery disease and test their relations to its extent and severity.

Methods and Results

100 patients with CAD [single-vessel (16%); two-vessel (39%); and three-vessel (42%) non-obstructed coronary arteries (3%)] were studied. CAD severity and extent was expressed as modified Gensini score (mean modified score 12.38 ± 5.3). A majority of carotid plaque was located in the carotid bulb (CB). Atherosclerosis in this most diseased segment correlated modestly with the severity and extent of CAD, as expressed by the modified Gensini score (R = 0.251, P < 0.05). Using the AHA plaque classification, atheroma class also associated with CAD severity (rho = 0.26, P < 0.05). The distal descending aorta contained the greatest plaque, which correlated with the degree of CAD (R = 0.222; P < 0.05), but with no correlation with the proximal descending aorta, which was relatively spared (R = 0.106; P = n. s.). Aortic distensibility varied along its length with the ascending aorta the least distensible segment. Brachial artery FMD was inversely correlated with modified Gensini score (R = -0.278; P < 0.05). In multivariate analysis, distal descending aorta atheroma burden, distensibility of the ascending aorta, carotid atheroma class and FMD were independent predictors of modified Gensini score.

Conclusions

Multimodal vascular CMR shows regional abnormalities of vascular structure and function that correlate modestly with the degree and extent of CAD.     

经食管超声心动图探查胸主动脉粥样梗化对冠状动脉粥样硬化的预测价值

本文采用经食管超声心动图技术观察了６４例行冠脉造影患者的胸主动脉粥样硬化病变。结果表明４２例阳性患者中ＴＥＥ发现３６例有胸主动脉粥样斑块，而２２例阴性中仅２例存在斑块，二者相比有高度显著性差异（Ｐ＜０．００１）。以冠脉造影结果为金标准，斑块为预测冠心病的指标，其敏感性８５．７％，特异性９０．９％。冠脉造影阳性组的胸主动脉粥样硬化病变多为Ⅱ、Ⅲ级，而阴性组多为０、Ⅰ级，二组差异显著（Ｐ＜０．００５）。多支冠脉病变组胸主动脉粥样梗化程度较单支组严重（Ｐ＜０．０１），但正常组和狭窄＜５０％组之间无显著差异（Ｐ＞０．０５）。本研究认为胸主动脉粥样斑块能预报有临床意义的冠状动脉狭窄，胸主动脉可作为了解冠状动脉粥样硬化程度的窗口     

Glagov remodeling of the atherosclerotic aorta demonstrated by cardiovascular magnetic resonance: the CORDA asymptomatic subject plaque assessment research (CASPAR) project.

BACKGROUND: Aortic atherosclerosis and coronary artery disease (CAD) are closely linked. Early detection of aortic atherosclerosis with the adoption of appropriate preventive measures may therefore help to reduce mortality and morbidity related to CAD. Arterial remodeling, by which the wall adapts to physiological or pathological insults by a change in vessel size, is being increasingly recognized as an important aspect of atherosclerosis. In this prospective longitudinal study we used cardiovascular magnetic resonance (CMR) to detect aortic plaque and to study aortic wall remodeling in asymptomatic subjects. METHODS: We recruited 175 healthy volunteers (49 years, 110 men) and documented their cardiovascular risk profile. Each subject underwent echocardiogram (ECG)-gated T1-weighted spin-echo imaging of the infrarenal abdominal aorta at baseline and after 2 years. FINDINGS: Of the 175 subjects who volunteered at baseline, CMR was successful in 174 (99%), with one (0.6%) failure due to claustrophobia. At 2 years, follow-up scanning was performed in 169 subjects (97%). Infrarenal aortic plaque was identified at baseline in nine (5.2%) subjects. This was reconfirmed in all nine (100%) cases at 2-year follow-up. No new cases of infrarenal plaque were identified at follow-up. The signal characteristics of the plaque on the subtracted images of the Dixon method indicate that all plaques were fibrous. In the nine subjects with infrarenal plaque, the total plaque burden increased as assessed by the total wall volume (561 to 677 mm3, p = 0.0063). The total vessel volume also increased (1737 to 1835 mm3, p = 0.031) but there was no change in the total luminal volume (1175 to 1157 mm3, p = 0.29). CONCLUSIONS: Cardiovascular magnetic resonance detects subclinical aortic atherosclerosis, can follow plaque burden over time, and confirms the presence of Glagov remodeling with preservation of the lumen despite progression of plaque. Cardiovascular magnetic resonance is well suited for the longitudinal follow-up of the general population with atherosclerosis, may help in the understanding of the natural history of atherosclerosis, and in particular may help determine factors to retard disease progression at an early stage.     

Topographic association of angioscopic yellow plaques with coronary atherosclerotic plaque: assessment with quantitative colorimetry in human coronary artery autopsy specimens

Yellow plaques seen during coronary angioscopy are thought to be the surrogates for superficial intimal lipids in coronary plaque. Given diffuse and heterogeneous nature of atherosclerosis, yellow plaques in coronaries may be seen as several yellow spots on diffuse coronary plaque. We examined the topographic association of yellow plaques with coronary plaque. In 40 non-severely stenotic ex-vivo coronary segments (average length: 52.2 ± 3.1 mm), yellow plaques were examined by angioscopy with quantitative colorimetry. The segments were cut perpendicular to the long axis of the vessel at 2 mm intervals, and 1045 slides with 5 μm thick tissue for whole segments were prepared. To construct the plaque surface, each tissue slice was considered to be representative of the adjacent 2 mm. The circumference of the lumen and the lumen border of plaque were measured in each slide, and the plaque surface region was constructed. Coronary plaque was in 37 (93%) of 40 segments, and consisted of a single mass [39.9 ± 3.9 (0–100) mm, 311.3 ± 47.4 (0.0–1336.2) mm²]. In 30 (75%) segments, multiple (2–9) yellow plaques were detected on a mass of coronary plaque. The number of yellow plaques correlated positively with coronary plaque surface area (r = 0.77, P < 0.0001). Yellow plaques in coronaries detected by angioscopy with quantitative colorimetry, some of them are associated with lipid cores underneath thin fibrous caps, may be used to assess the extent of coronary plaque. Further research using angioscopy could be of value to study the association of high-risk coronaries with acute coronary syndromes.     

Aortic pathophysiology by cardiovascular magnetic resonance in patients with clinical suspicion of coronary artery disease.

PURPOSE: To correlate cardiovascular magnetic resonance (CMR)-based measurement of aortic pulse wave velocity (PWV) with serum markers for atherosclerosis and plaque burden in the thoracic aorta. METHOD: Individuals with risk factors for coronary atherosclerosis underwent CMR pulse wave velocity examination of the descending thoracic aorta and computed tomography for coronary calcium scoring. Inversion recovery images allowed quantification of aortic plaque. Serum lipids and c-reactive protein levels were measured. RESULTS: Mean PWV did not correlate with presence of aortic plaque (p = 0.55). Subgroup analysis showed no significant correlation with PWV and total plaque. PWV and pulse pressure correlated (PP) (R2 0.38, p = 0.0003), but PWV and other predictor variables did not. Total plaque area correlated with aortic diameter (p = 0.0066). CONCLUSIONS: In patients with suspected coronary artery disease, aortic pulse wave velocity reflects increased aortic stiffness demonstrated by elevated pulse pressure, but does not directly correlate with aortic plaque or serum markers for arterial disease.     

经食管超声对冠心病患者胸主动脉粥样硬化的研究

目的　探讨胸主动脉粥样硬化与冠状动脉粥样硬化的关系。方法　用多平面经食管超声技术, 检测了４１例正常人和４９例冠心病患者胸主动脉。对胸主动脉内径、内膜－中层厚度（ＩＭＴ）、僵硬度（β）和粥样斑块进行了评价。结果　与对照组比较, 冠心病组胸主动脉内径扩大, ＩＭＴ增厚, β值增大（Ｐ＜ ０．０５～０．００１）; 胸主动脉粥样斑块对冠心病诊断的敏感性为６３．２７％ , 特异性为９７．５６％ 。阳性预测值为９６．８８％ , 阴性预测值为６８．９７％ 。结论　冠心病人胸主动脉的解剖和功能发生了明显的变化; 胸主动脉粥样斑块是预测冠心病的较为敏感而特异的指标。     

Association of atherosclerosis in the descending thoracic aorta with coronary artery disease on multi detector row computed tomography coronary angiography in patients with suspected coronary artery disease

The association between atherosclerosis in the descending thoracic aorta (DTA) visualized on computed tomography coronary angiography (CTA) and coronary artery disease (CAD) has not been extensively explored. Therefore, a comprehensive analysis of DTA atherosclerosis on CTA was performed and the association of DTA atherosclerosis with CAD was evaluated in patients with suspected CAD. A total of 344 patients (54 ± 12 years, 54 % men) with suspected CAD underwent CTA. CTA were classified based on CAD severity in no signs of atherosclerosis or minor wall-irregularities <30 %, non-significant CAD 30–50 %, or significant CAD ≥50 % stenosis. The DTA was divided in segments according the posterior intercostal arteries. Per segment the presence of atherosclerotic plaque (defined as ≥2 mm wall thickness) was determined and maximal wall thickness was measured. Plaque composition was scored as non-calcified or mixed and the percentage of DTA segments with atherosclerosis was calculated. Significant CAD was present in 152 (44 %) patients and 278 (81 %) had DTA atherosclerotic plaque. DTA maximal wall thickness and percentage of DTA segments with atherosclerosis were 2.7 ± 1 mm and 49 ± 36 %. The presence, severity and extent of DTA atherosclerosis significantly increased with increasing CAD severity. Multivariate logistic regression analysis corrected for age and other risk factors demonstrated independent associations of DTA plaque (OR 6.56, 95 % CI 1.78–24.19, p = 0.005) and maximal DTA wall thickness (OR 2.00, 95 % CI 1.28–3.12, p = 0.002) with significant CAD. The presence and severity of DTA atherosclerosis were independently related with significant CAD on CTA in patients with suspected CAD.     

胸主动脉粥样斑块的经食管超声研究

本文应用多平面经食管超声技术检测了２４０例受试者的胸主动脉，旨在探讨胸主动脉粥样斑块的超声特征、好发部位及临床意义。结果显示，检出斑块７３例，其中单纯型占５８．９０％，复合型占４２．４６％。复合型斑块的发生率在心脑血管病变组明显高于高血压组（５２．９０％ＶＳ１９．０５％，Ｐ＜０．０１）。胸主动脉粥样斑块的好发部位为同时发生于主动脉弓和降主动脉（５８．９１％），其次为降主动脉（２１．９５）和主动脉弓部（１９．２５％），Ｐ均＜０．００１。结果表明，复合型斑块与心脑血管病变密切相关，经食管超声技术是检测活体胸主动脉粥样硬化病变的重要方法     

动脉粥样硬化兔斑块易损性的血管内超声评价

目的应用血管内超声（IVUS）技术评价易损斑块的影像学特征。方法30只实验兔给予球囊损伤腹主动脉＋高脂饲料喂养，12周末将实验兔随机分为A、B两组，在A组腹主动脉斑块处转染携带人野生型P53基因的重组腺病毒载体，2周后给予所有兔中国斑点蝰蛇毒（CRVV）和组胺触发，14周末进行体表超声、血管内超声和病理学检查。结果A组斑块破裂率较B组显著增高（P〈0．05）。IVUS示斑块破裂组的血管外弹力膜面积（EEMA）、斑块面积（PA）、管腔面积狭窄百分率（LAS%）及偏心指数（EI）显著大于未破裂组（P〈0．01～0．05）；斑块破裂组的内一中膜厚度（IMT）、收缩期峰值流速（Vp）显著大于未破裂组，而平均回声强度的校正值（AIIc％）显著低于未破裂组（P均〈0．05）。结论应用野生型P53基因转染可导致斑块的不稳定性，IVUS能够准确识别易损斑块，为临床早期发现易损斑块并预测斑块破裂提供了可靠的方法。     

心脏瓣膜病胸主动脉CT重建特征及其临床意义

目的 观察心脏瓣膜病胸主动脉CT重建特征及其临床意义。方法 选取2018年10月～2021年12月北碚区中医医院放射科收治的300例患者作为研究对象,将95例心脏瓣膜病患者纳入病例组,205例非心脏瓣膜病变的普通患者纳入对照组,均行CT增强扫描和三维重建,比较两组的临床一般资料和CT测量值（包括胸主动脉长度、主动脉峡部直径和膈肌层面主动脉直径）,采用Logistic分析患者胸主动脉长度的影响因素。结果 病例组患者的胸主动脉长度、主动脉峡部直径和膈肌层面主动脉直径均高于对照组,差异有统计学意义（P<0.05）,心脏瓣膜病变患者主要CT特征为主动脉扩张,瓣膜增厚;不同年龄、性别、高血压和主动脉壁斑块、心脏瓣膜病的患者胸主动脉长度比较,差异有统计学意义（P<0.05）;年龄（OR=2.121）、主动脉壁斑块（OR=2.234）、心脏瓣膜病（OR=1.964）是影响患者胸主动脉长度的因素,差异有统计学意义（P<0.05）。结论 心脏瓣膜病患者胸主动脉增长、主动脉峡部及膈肌层面增长增宽,同时胸主动脉长度受年龄、主动脉壁斑块和心脏瓣膜病的影响,了解其形态特征,对于主动脉手术治疗具...     

Guided review by frequent itemset mining: additional evidence for plaque detection

Purpose  A guided review process to support manual coronary plaque detection in computed tomography coronary angiography (CTCA) data sets is proposed. The method learns the spatial plaque distribution patterns by using the frequent itemset mining algorithm and uses this knowledge to predict potentially missed plaques during detection. Materials and methods  Plaque distribution patterns from 252 manually labeled patients who underwent CTCA were included. For various cross-validations a labeling with missing plaques was created from the initial manual ground truth labeling. Frequent itemset mining was used to learn the spatial plaque distribution patterns in form of association rules from a training set. These rules were then applied on a testing set to search for segments in the coronary tree showing evidence of containing unlabeled plaques. The segments with potentially missed plaques were finally reviewed for the existence of plaques. The proposed guided review was compared to a weighted random approach that considered only the probability of occurrence for a plaque in a specific segment and not its spatial correlation to other plaques. Results  Guided review by frequent itemset mining performed significantly better (p < 0.001) than the reference weighted random approach in predicting coronary segments with initially missed plaques. Up to 47% of the initially removed plaques were refound by only reviewing 4.4% of all possible segments. Conclusions  The spatial distribution patterns of atherosclerosis in coronary arteries can be used to predict potentially missed plaques by a guided review with frequent itemset mining. It shows potential to reduce the intra- and inter-observer variability.     

Epicardial adipose tissue thickness predicts descending thoracic aorta atherosclerosis shown by multidetector computed tomography

Human epicardial adipose tissue (EAT) is a type of visceral adipose tissue functioning as an endocrine organ by secreting hormones and adipocytokines which have an important role in the atherosclerotic process. In this study, we aimed to assess the relationship between EAT measured by dual source multidetector computed tomography (MDCT) and descending thoracic aorta (DTA) atherosclerosis. A total of 148 patients who underwent MDCT for the evaluation of coronary artery disease were enrolled in this study. Thickness of the EAT was measured on contrast enhanced multiplanar reformat images with parasternal short axis view at basal, mid-ventricular and apical levels and horizontal long axis view. The atherosclerotic plaque was scored from 0 to 4 points by the percentage of the luminal surface at the cross sectional area of proximal, mid and distal segments of descending aorta. Among the study population, 84 (56.8%) were male and age was (mean ± standart deviation) 56.9 ± 11.7 years. In patients with critical coronary atherosclerosis, DTA atherosclerosis had a significant relationship with EAT (P = 0.012). Multivariate linear regression analysis revealed that in addition to critical coronary stenosis, age and total epicardial fat thickness were associated with aortic atherosclerosis (β value, 0.058 and 0.035; t value, 4.74 and 2.28, respectively; P < 0.05) after adjustment for traditional cardiovascular risk factors. In this study we demonstrated that atherosclerotic plaque burden of DTA was associated with the amount of EAT thickness among patients with suspected CAD shown by MDCT. Further large scale prospective studies are needed to address the interaction of EAT as well as the mediators of inflammation and adipocytokines with the development of atherosclerotic plaques in aorta and effects on cardiovascular outcomes.     

BOLD cardiovascular magnetic resonance at 3.0 tesla in myocardial ischemia

Background

The purpose of this study was to determine the ability of Blood Oxygen Level Dependent (BOLD) cardiovascular magnetic resonance (CMR) to detect stress-inducible myocardial ischemic reactions in the presence of angiographically significant coronary artery disease (CAD).

Methods

Forty-six patients (34 men; age 65 ± 9 years,) with suspected or known coronary artery disease underwent CMR at 3Tesla prior to clinically indicated invasive coronary angiography. BOLD CMR was performed in 3 short axis slices of the heart at rest and during adenosine stress (140 μg/kg/min) followed by late gadolinium enhancement (LGE) imaging. In all 16 standard myocardial segments, T2* values were derived at rest and under adenosine stress. Quantitative coronary angiography served as the standard of reference and defined normal myocardial segments (i.e. all 16 segments in patients without any CAD), ischemic segments (i.e. supplied by a coronary artery with ≥50% luminal narrowing) and non-ischemic segments (i.e. supplied by a non-significantly stenosed coronary artery in patients with significant CAD).

Results

Coronary angiography demonstrated significant CAD in 23 patients. BOLD CMR at rest revealed significantly lower T2* values for ischemic segments (26.7 ± 11.6 ms) compared to normal (31.9 ± 11.9 ms; p < 0.0001) and non-ischemic segments (31.2 ± 12.2 ms; p = 0.0003). Under adenosine stress T2* values increased significantly in normal segments only (37.2 ± 14.7 ms; p < 0.0001).

Conclusions

Rest and stress BOLD CMR at 3Tesla proved feasible and differentiated between ischemic, non-ischemic, and normal myocardial segments in a clinical patient population. BOLD CMR during vasodilator stress identified patients with significant CAD.     

Extracellular volume fraction mapping in the myocardium, part 2: initial clinical experience

Background

The purpose of this study was to quantify myocardial strain on the subendocardial and epicardial layers of the left ventricle (LV) using tagged cardiovascular magnetic resonance (CMR) and to investigate the transmural degree of contractile impairment in the chronic ischemic myocardium.

Methods

3T tagged CMR was performed at rest in 12 patients with severe coronary artery disease who had been scheduled for coronary artery bypass grafting. Circumferential strain (C-strain) at end-systole on subendocardial and epicardial layers was measured using the short-axis tagged images of the LV and available software (Intag; Osirix). The myocardial segment was divided into stenotic and non-stenotic segments by invasive coronary angiography, and ischemic and non-ischemic segments by stress myocardial perfusion scintigraphy. The difference in C-strain between the two groups was analyzed using the Mann-Whitney U-test. The diagnostic capability of C-strain was analyzed using receiver operating characteristics analysis.

Results

The absolute subendocardial C-strain was significantly lower for stenotic (-7.5 ± 12.6%) than non-stenotic segment (-18.8 ± 10.2%, p < 0.0001). There was no difference in epicardial C-strain between the two groups. Use of cutoff thresholds for subendocardial C-strain differentiated stenotic segments from non-stenotic segments with a sensitivity of 77%, a specificity of 70%, and areas under the curve (AUC) of 0.76. The absolute subendocardial C-strain was significantly lower for ischemic (-6.7 ± 13.1%) than non-ischemic segments (-21.6 ± 7.0%, p < 0.0001). The absolute epicardial C-strain was also significantly lower for ischemic (-5.1 ± 7.8%) than non-ischemic segments (-9.6 ± 9.1%, p < 0.05). Use of cutoff thresholds for subendocardial C-strain differentiated ischemic segments from non-ischemic segments with sensitivities of 86%, specificities of 84%, and AUC of 0.86.

Conclusions

Analysis of tagged CMR can non-invasively demonstrate predominant impairment of subendocardial strain in the chronic ischemic myocardium at rest.     

Plasma osteopontin as a predictor of coronary artery disease: association with echocardiographic characteristics of atherosclerosis

Osteopontin (OPN), a bone‐related protein, is present within the atherosclerotic plaques, most strikingly in calcified plaques. Valvular calcifications are accepted as a part of the spectrum of atherosclerosis and are associated with atherosclerotic calcification in the coronary arteries. The study aimed to evaluate the association of plasma OPN with the presence and extent of coronary stenosis, mitral annular calcification (MAC), and aortic valve sclerosis in stable angina patients. We studied 120 subjects who underwent coronary angiography because of ischemic chest pain. Coronary artery disease (CAD) was defined as ≥50% stenosis in ≥1 coronary artery. MAC and aortic valve sclerosis were detected by echocardiography. Lipid profile, high sensitive C‐reactiveprotein (hsCRP), and OPN were measured in all studied subjects. Patients with CAD had increased plasma OPN when compared with those without CAD (P<0.001). Plasma OPN levels were significantly positively correlated with atherogenic lipid profile, hsCRP, MAC grading, aortic valve sclerosis grading, and the number of stenosed coronary vessels in CAD patients. In multivariate analysis, OPN was an independent predictor of CAD (P=0.01), MAC (P=0.01), and aortic valve sclerosis (P=0.04). In conclusion, OPN is an independent predictor of MAC and aortic valve sclerosis. Plasma OPN levels reflect the extent of coronary stenosis and can be used as a biomarker to identify patients with coronary atherosclerosis. J. Clin. Lab. Anal. 24:201–206, 2010. © 2010 Wiley‐Liss, Inc.     

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.