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1.
A positive exercise electrocardiogram (ECG) is not infrequent occurrence in asymptomatic hypercholesterolemic patients, but the number of false-positive tests may be relatively high (50%). Therefore, the ability of a positive stress ECG to predict coronary artery lesions is low even in populations with > or =1 cardiovascular risk factors. To increase the diagnostic value of exercise tests for screening asymptomatic individuals, we analyzed whether combined clinical parameters with carotid echography would accurately predict coronary atherosclerotic lesions by coronary angiography in asymptomatic hypercholesterolemic patients with a positive exercise ECG. Seventy-six asymptomatic patients (between 35 and 65 years of age) with hypercholesterolemia (total plasma cholesterol >6.5 mmol/L or 250 mg/dl) and a positive stress ECG were referred for carotid B-mode echography and coronary angiography. Carotid echography data were divided into 2 categories: (1) absence of any atherosclerotic plaque, or (2) presence of > or =1 arterial plaques. Coronary stenosis assessed by coronary angiography was considered to correspond to a > or =50% reduction of coronary lumen diameter. Forty-three patients (57%) displayed coronary lesions; most (38; 88%) had carotid plaque. Multivariate analysis showed that the presence of carotid plaque was significantly associated with coronary stenosis (odds ratio 15.2; confidence interval 5.0 to 54.5). In subgroups characterized by high frequency of false-positive exercise electrocardiographic tests (women and patients with a 10-year predicted risk of coronary artery disease [CAD] <15%), none of the patients without carotid plaque exhibited coronary lesions. Echographic evaluation of carotid plaque (plaque vs no plaque) significantly improved the diagnostic specificity of exercise electrocardiography. We conclude that the combination of clinical, electrical, and echographic data facilitates cost-effective noninvasive detection of CAD in asymptomatic hypercholesterolemic patients.  相似文献   

2.
The aim of this study was to compare coronary artery plaque burden, composition, distribution, and the degree of coronary artery stenosis in diabetic and nondiabetic patients with known or suspected coronary artery disease (CAD). The study group consisted of 594 patients with known or suspected CAD, including 122 diabetics, who underwent multidetector computed tomographic coronary angiography and traditional invasive coronary artery angiography. Coronary artery calcium scores were compared in different age subgroups. Noncalcified plaque, calcified plaque, and mixed plaque were analyzed by coronary segment on computed tomographic coronary angiography, as well as the degree of coronary stenosis on coronary artery angiography. Obstructive vessels were compared between the 2 groups. Total coronary artery calcium score was higher in patients with diabetes compared to those without (378.4 ± 613.0 vs 226.0 ± 408.4, p = 0.003). The percentage of patients with coronary artery calcium scores >400 among diabetics (22.1%) was higher than among nondiabetics (14.2%) (p = 0.032). Diabetics had a higher percentage of coronary segments with noncalcified plaque, calcified plaque, and mixed plaque than nondiabetics (35.3% vs 26.2%, p <0.001; 17.5% vs 11.6%, p = 0.017; and 9.8% vs 7.9%, p = 0.008). More diabetics had multivessel obstructive disease compared to nondiabetics (p <0.05). With longer duration of diabetes mellitus, the stenosed segments of coronary arteries increased accordingly. In conclusion, diabetics have more atherosclerotic plaque burden and more severe coronary atherosclerosis than nondiabetics. Most obstructive lesions were caused by mixed plaques in diabetics and nondiabetics.  相似文献   

3.
冠心病是严重影响人类健康的一种常见的重大疾病。在临床症状出现之前及早诊断冠状动脉疾病有着重要的意义。尽管常规冠状动脉造影术仍然是诊断冠心病的“金标准” ,但一些其它非介入技术的应用具有代替常规冠脉造影术的潜在可能性。这样 ,冠状动脉疾病的非介入诊断成为当今医学关心的问题。新一代的多层螺旋CT具有高的分辨率 ,可以对心脏及冠状动脉进行显像评价。它不仅可以直接检测冠脉管腔狭窄 ,而且可以检测冠脉粥样硬化斑块。虽然由于冠脉运动尤其是右冠和回旋支中、远段造成的伪影 ,限制了MSCT的应用 ,但在获得足够的冠脉显像质量的情况下 ,多层螺旋CT冠脉管腔显像诊断明确狭窄的敏感性及特异性达 90 %左右。近几年来 ,CT技术的进步和显像质量的提高为冠脉显像诊断提供了日益增加的临床价值。另一方面 ,多层螺旋CT通过对冠脉钙化的评价 ,进行冠脉斑块负荷的测量 ,可评价、预测心血管病的危险性。通过钙化斑块负荷和造影剂管腔显像结合可增加诊断的准确性。总之 ,MSCT作为评价冠状动脉疾病的非介入方法正在快速发展 ,将来可能成为一种有前途的诊断方法。  相似文献   

4.
The understanding of concepts in coronary artery disease, such as the vulnerable or high-risk plaque, which accounts for many acute coronary events arising from non-flow-limiting coronary lesions, has advanced remarkably. Although coronary angiography is an established imaging technique for visualizing atherosclerotic disease, it is limited by its two-dimensional imaging aspect and a low sensitivity for identifying lesions in the presence of positive remodeling and diffuse disease. Moreover, coronary atherosclerotic plaques cannot be characterized. Although intravascular ultrasound is currently the most commonly employed adjunctive method to better define lesions, it is limited by low resolution. The development of new technologies for improved coronary plaque characterization has, thus, been desired. Optical coherence tomography is a developing technique that uses near-infrared light for the cross-sectional visualization of the vessel wall at the microscopic level. It enables excellent resolution of coronary architecture and precise characterization of plaque architecture. Quantification of macrophages within the plaque is also possible. These capabilities allow precise identification of the most common type of vulnerable plaque, the thin-cap fibroatheroma. Here, we discuss results from clinical studies which indicate that optical coherence tomography is a promising imaging technique for improved characterization of the coronary atherosclerotic plaque.  相似文献   

5.
目的探讨冠心病患者中肾动脉狭窄(ARAS)的患病率及其相关因素。方法228例冠脉造影患者同时行选择性双肾动脉造影检查,对临床资料和ARAS之间的关系进行单因素和多因素Logistic回归分析。结果228例患者中,ARAS患病率为19.7%;经冠脉造影证实的152例冠心病患者中,ARAS患病率为27.6%;51例冠心病合并颈动脉粥样斑块的患者中,ARAS患病率为49.0%。45例ARAS患者中,左肾动脉狭窄的患病率显著高于右肾动脉(P<0.05)。单因素分析表明,年龄、糖尿病、肾功能不全、颈动脉粥样斑块、冠心病是ARAS的预测因素。多元Logistic回归分析表明,仅年龄、颈动脉粥样斑块、冠脉三支病变是ARAS的独立预测因素。结论对于冠心病患者,尤其是年龄≥60岁及合并颈动脉粥样斑块的患者,冠脉造影后应常规行肾动脉造影,以便早期发现ARAS。  相似文献   

6.
Coronary computed tomographic angiography (CCTA) has emerged as a novel noninvasive method for the evaluation of not only coronary artery stenosis but also arterial wall and plaque features. Recent developments in CCTA technology enable the simultaneous assessment of coronary stenosis, atherosclerotic plaque characteristics, physiologic significance of lesion-specific ischemia, and cardiac function. Through these studies, the prognostic significance of individual coronary lesions and ventricular function can be determined and used to direct therapy. Future studies are needed to establish the totality of coronary artery plaque measures that improve clinical utility.  相似文献   

7.
ObjectivesThe aim of this study was to precisely phenotype culprit and nonculprit lesions in myocardial infarction (MI) and lesions in stable coronary artery disease (CAD) using coronary computed tomography angiography (CTA)-based radiomic analysis.BackgroundIt remains debated whether any single coronary atherosclerotic plaque within the vulnerable patient exhibits unique morphology conferring an increased risk of clinical events.MethodsA total of 60 patients with acute MI prospectively underwent coronary CTA before invasive angiography and were matched to 60 patients with stable CAD. For all coronary lesions, high-risk plaque (HRP) characteristics were qualitatively assessed, followed by semiautomated plaque quantification and extraction of 1,103 radiomic features. Machine learning models were built to examine the additive value of radiomic features for discriminating culprit lesions over and above HRP and plaque volumes.ResultsCulprit lesions had higher mean volumes of noncalcified plaque (NCP) and low-density noncalcified plaque (LDNCP) compared with the highest-grade stenosis nonculprits and highest-grade stenosis stable CAD lesions (NCP: 138.1 mm3 vs 110.7 mm3 vs 102.7 mm3; LDNCP: 14.2 mm3 vs 9.8 mm3 vs 8.4 mm3; both Ptrend < 0.01). In multivariable linear regression adjusted for NCP and LDNCP volumes, 14.9% (164 of 1,103) of radiomic features were associated with culprits and 9.7% (107 of 1,103) were associated with the highest-grade stenosis nonculprits (critical P < 0.0007) when compared with highest-grade stenosis stable CAD lesions as reference. Hierarchical clustering of significant radiomic features identified 9 unique data clusters (latent phenotypes): 5 contained radiomic features specific to culprits, 1 contained features specific to highest-grade stenosis nonculprits, and 3 contained features associated with either lesion type. Radiomic features provided incremental value for discriminating culprit lesions when added to a machine learning model containing HRP and plaque volumes (area under the receiver-operating characteristic curve 0.86 vs 0.76; P = 0.004).ConclusionsCulprit lesions and highest-grade stenosis nonculprit lesions in MI have distinct radiomic signatures compared with lesions in stable CAD. Within the vulnerable patient may exist individual vulnerable plaques identifiable by coronary CTA-based precision phenotyping.  相似文献   

8.
The treatment of coronary artery disease (CAD), which is defined by stable anatomical atherosclerotic and functional alterations of epicardial vessels or microcirculation, focuses on managing intermittent angina symptoms and preventing major adverse cardiovascular events with optimal medical therapy. When patients with known CAD present with angina and no acute coronary syndrome, they have historically been evaluated with a variety of noninvasive stress tests that utilize electrocardiography, radionuclide scintigraphy, echocardiography, or magnetic resonance imaging for determining the presence and extent of inducible myocardial ischemia. Patient event-free survival, however, is largely driven by the coronary atherosclerotic disease burden, which is not directly assessed by functional testing. Direct evaluation of coronary atherosclerotic disease by coronary computed tomography angiography (coronary CTA) has emerged as the first line noninvasive imaging modality as it improves diagnostic accuracy and positively influences clinical management. Compared to functional assessment of CAD, coronary CTA-guided management results in improved patient outcomes by facilitating prevention of myocardial infarction. Other strengths of coronary CTA include detailed atherosclerotic plaque characterization and the ability to assess functional significance of specific lesions, which may further improve risk assessment and prognosis and lead to more appropriate referrals for additional testing, such as invasive coronary angiography.  相似文献   

9.
Atherosclerosis develops simultaneously in multiple arterial beds, that creates opportunity to diagnose of coronary artery disease. Aim of the study was the evaluation of association between atherosclerotic involvement of peripheral arteries assessed by ultrasound and significant coronary artery disease revealed by angiography. Study included 410 patients, (73% males), mean age 56.0 +/- 9.5 year scheduled for coronary angiography. During ultrasound examination of common carotid and common femoral arteries arterial wall intima-media (IMT) thickness and atherosclerotic plaques presence were assessed. Significant coronary artery disease (CAD) was diagnosed with coronary angiography as diameter stenosis > 50%. Intimo-media thickness (IMT) of common carotid arteries did not differ between groups with and without significant coronary artery disease (right 6.6 vs 6.4 mm, p = ns, left 6.9 vs 6.6 mm, p = ns) but in common femoral arterial was greater in patients with coronary artery disease (right 8.2 vs 7.1 mm, p < 0.005, left 7.9 vs 7.1 mm, p = 0.03). Atherosclerotic plaques in carotid and femoral arteries was detected more often in CAD patients (90.1% vs 34.6%, p < 0.0001). Positive predictive value for CAD diagnosis with detection of plaque in carotid or femoral artery was 93% and negative prognostic value for exclusion CAD after plaque exclusion in all arteries was 61%. Search for atherosclerotic plaques in ultrasound examination of peripheral arteries may facilitate CAD diagnosis in selected patients groups.  相似文献   

10.
Coronary arterial remodeling: From bench to bedside   总被引:1,自引:0,他引:1  
Coronary arterial remodeling describes changes of vessel size at the site of atherosclerotic lesions. Positive remodeling (expansion) of early lesions maintains lumen size despite plaque accumulation. In contrast, negative remodeling (shrinkage) contributes to luminal stenosis independent of plaque accumulation. Because of these adaptive changes, plaque progression/regression is not closely reflected in luminal size. Histologic studies have demonstrated that the pathophysiologic role of arterial remodeling is more complex than a mere compensatory process. Surprisingly, there is a consistent association between positive arterial remodeling, local inflammatory response, and plaque vulnerability. In vivo tomographic imaging techniques, in particular intravascular ultrasound, and potentially computed tomography and magnetic resonance imaging, allow the observation of remodeling in clinical settings. The integration of basic knowledge about arterial remodeling with clinical observations from in vivo imaging could lead to a better understanding of plaque progression, regression, and vulnerability and may eventually have implications for disease prevention.  相似文献   

11.
目的探讨64层螺旋CT冠状动脉成像及冠状动脉彩色编码技术在冠心病诊断的临床应用。方法对74例临床拟诊冠心病的患者进行64层螺旋CT冠状动脉成像检查。重建冠状动脉图像,显示冠状动脉分支血管,测量冠状动脉狭窄程度、长度;对检出的86段粥样硬化斑块采用彩色编码技术进行标记和测算。结果64层螺旋CT冠状动脉成像受心率影响较大,在控制心率≤70次/min时,冠状动脉1-13段血管97.4%(823/845)图像质量为1级,粥样硬化斑块及冠状动脉狭窄清晰显示。彩色编码技术检出不稳定斑块27块,其中19个斑块导致冠状动脉26%~50%狭窄,5个斑块导致冠状动脉51%-75%狭窄。结论64层螺旋CT冠状动脉成像及冠状动脉彩色编码技术可以非创伤性地显示冠状动脉狭窄程度及导致冠状动脉狭窄的斑块中各成分形态、分布及比例,可作为对冠心病患者进行筛查及初步预后评估的首选方法。  相似文献   

12.
BACKGROUND: The presence of atherosclerotic lesions in the thoracic aorta by transesophageal echocardiography (TEE) appears to be a marker for the presence of significant coronary artery disease (CAD) in the general population. HYPOTHESIS: We investigated whether atherosclerotic lesions in the thoracic aorta, by multiplane TEE, could be a marker for CAD in elderly patients. METHODS: In all, 127 patients (67 men, 60 women, aged 68 +/- 13 years), underwent a TEE study with imaging of the thoracic aorta and cardiac catheterization with coronary angiography. The presence of a distinct, linear, or focal, highly echogenic mass protruding into the vessel lumen was the criterion for the diagnosis of atherosclerotic plaque. RESULTS: Atherosclerotic lesions were found in 30 of 36 patients (83.3%) with and in 20 of 91 (22%) without CAD. Of the 41 patients > or = 70 years, atherosclerotic lesions were detected in 14 of 17 (82.3%) with and in 13 of 24 patients (54%) without CAD. The sensitivity, specificity, and positive and negative predictive values in this group were 82.3, 46, 52, and 78.6%, respectively. Multivariate logistic regression analysis revealed that in patients aged > or = 70 years only advanced atherosclerotic lesions were independent predictors of significant CAD. However, the high negative predictive value of the method indicates that the absence of aortic plaque is a strong predictor of the absence of CAD. CONCLUSIONS: The presence of atherosclerotic lesions in the thoracic aorta is a strong predictor of CAD only in patients < 70 years old. However, the negative predictive value of the method is high for all patients regardless of age.  相似文献   

13.
目的 探讨人冠状动脉粥样硬化病变中CD68-阳性巨噬细胞的分布以及与冠状动脉粥样硬化病变类型、管腔狭窄之间的关系及其意义.方法 选用53例尸检病例的312块冠状动脉组织标本,光镜下诊断弥漫性内膜增厚和冠状动脉粥样硬化病变及其类型,用免疫组织化学计数冠状动脉粥样硬化病变中CD68-阳性巨噬细胞,用Scion图像软件系统检测和计算冠状动脉标本中管腔狭窄程度、脂质坏死核心和钙化基质面积.结果 在冠状动脉粥样病变中, 40% (124/312)为弥漫性内膜增厚, 5% (16/312)为Ⅰ型, 10% (31/312)为Ⅱ型, 21% (66/312)为Ⅲ型, 4% (14/312)为Ⅳ型, 18% (55/312)为Ⅴ型和2% (6/312)为Ⅵ型.脂质坏死核心面积在高胆固醇组明显大于正常胆固醇组(P<0.05),而钙化基质面积在早期病变(Ⅰ~Ⅲ型)和进展期病变(Ⅳ~Ⅵ型)之间有显著性差异(P<0.05);冠状动脉粥样硬化病变CD68-阳性巨噬细胞随着冠状动脉粥样硬化病变进展和管腔狭窄程度的加重而增多,分别呈正相关(P<0.01),且不同病变类型、管腔狭窄程度之间以及正常胆固醇组与高胆固醇组之间有显著性差异(P<0.05).结论 CD68-阳性巨噬细胞随着人冠状动脉粥样硬化病变进展和管腔狭窄程度的加重而增多,表明巨噬细胞浸润始终始发和加重冠状动脉粥样硬化病变,大量巨噬细胞主要在斑块肩部区浸润和脂质坏死核心的增大与冠状动脉粥样硬化病变进展、不稳定性斑块破裂及并发症的发生有关.  相似文献   

14.
腺苷负荷心肌灌注显像在老年冠心病患者诊断中的价值   总被引:1,自引:0,他引:1  
目的评价腺苷负荷心肌灌注显像试验对老年人冠心病的诊断价值以及对病变血管部位、血管支数、狭窄程度所作的评估。方法选择116例可疑冠心病的老年患者,行腺苷负荷心肌灌注显像。腺苷注射液按140μg/(kg.min)在6min内匀速静脉泵入。当腺苷泵入3min时经三通管快速静推99m锝-2-甲氧基异丁基异腈(99mTc-MIBI);1.5h后进行心肌灌注断层显像。若显像异常,次日行静息心肌显像。所有患者腺苷负荷心肌灌注显像后行冠状动脉造影。结果在116例患者中,73例冠状动脉造影显示明显的冠状动脉狭窄病变,其中单支病变22例,两支病变32例,三支病变19例。腺苷负荷心肌灌注显像试验诊断冠心病的敏感度、特异度和准确度分别为87.7%、72.1%和65.5%。诊断单支、两支和三支冠状动脉病变患者的敏感度分别为59.1%、84.4%和89.5%(P0.05)。对管径狭窄为50%~75%组的敏感度为57.1%,管径狭窄≥75%组的敏感度为89.4%,两组间比较有统计学意义(P0.05)。无论是单支病变、两支病变还是三支病变,累及前降支血管病变的心肌核素的阳性率均高(P0.05)。行血管内超声检查的17例患者中,有7例病变斑块面积狭窄率50%或管腔面积4mm2,有偏心或不稳定性斑块,给予冠脉介入治疗,而此7例腺苷负荷心肌核素均为阳性。结论腺苷负荷心肌灌注断层显像诊断老年患者冠心病的敏感度与冠脉狭窄程度和病变支数相关。对重度狭窄和两支、三支病变的患者有较高的敏感度,但对轻中度狭窄和单支病变的患者敏感度较低。腺苷负荷心肌灌注断层显像预测左前降支病变的阳性符合率高于左回旋支和右冠状动脉,且对临界病变的预测有一定价值。  相似文献   

15.
The composition of the atherosclerotic lesion rather than the degree of stenosis is currently considered to be the most important determinant for acute clinical events. Modalities capable of characterizing the atherosclerotic lesion may be helpful in understanding its natural history and detecting lesions with high risk for acute events. Speaking grossly, three histologic features of the vulnerable plaque have been reported: size of the atheroma, thickness of the fibrous cap, and inflammation. Imaging techniques are currently being deployed and are under development to aid visualization of the vulnerable coronary plaque. Most of these diagnostic modalities have the potential to detect locally one or more of the three histologically defined features of vulnerable plaque. This review will focus on imaging techniques that have been developed to characterize the atherosclerotic lesion. Most catheter-based visualization techniques will provide insight into components of the local atherosclerotic plaque which may limit their predictive value for the occurrence of a clinical event. Therefore, the clinical relevance of these imaging tools will be discussed.  相似文献   

16.
Atherosclerotic lesions in the thoracic aorta detected by transesophageal echocardiography (TEE) have been correlated with coronary artery disease (CAD). We determined whether simple or complex aortic plaques seen on transesophageal echocardiogram correlated with extent, location, and severity of CAD. The study population consisted of 188 patients who underwent TEE and coronary angiography. Atherosclerotic plaques seen on transesophageal echocardiogram were defined as (1) complex plaques in the presence of protruding atheroma ≥4-mm thickness, mobile debris, or plaque ulceration or (2) simple plaques in the absence of findings consistent with complex plaques. Extent of CAD was grouped into 4 groups according to number of coronary vessels with ≥70% stenosis. Numbers of patients with CAD with 0-, 1-, 2-, and 3-vessel disease were 99, 31, 28, and 30 respectively. Compared to patients without CAD, patients with CAD (n = 89) had a significantly greater prevalence of aortic atherosclerotic plaques irrespective of degree of plaque complexity or location (p <0.05). Multivariate analysis found that hypertension (odds ratio 3.0, 95% confidence interval 1.3 to 7.0, p = 0.013), diabetes mellitus (odds ratio 2.4, 95% confidence interval 1.1 to 4.9, p = 0.022), and aortic plaque (odds ratio 3.8, 95% confidence interval 1.8 to 8.2, p = 0.001) were significantly associated with CAD. There was a significant relation between simple and complex aortic plaques with increasing severity of CAD (p <0.001). Multivariate logistic regression analysis showed that complex plaque in the descending aorta (odds ratio 5.4, 95% confidence interval 1.8 to 16.4, p = 0.003) was the strongest predictor of CAD. In conclusion, simple and complex thoracic atherosclerotic plaques detected by TEE are associated with increasing severity of CAD. Complex plaque in the descending aorta was the strongest association with presence of CAD.  相似文献   

17.
目的: 评估稳定型冠状动脉疾病(stable coronary artery disease, CAD)患者血清白细胞介素-6(IL-6)、可溶性IL-6受体(sIL-6R)和可溶性糖蛋白130(sgp130)浓度及与冠状动脉粥样硬化严重程度间的关系。方法:纳入2017年1月到2019年1月间于惠州市第六人民医院心内科具有动脉造影适应症疑似冠心病患者89例,根据冠状动脉造影结果将患者分成两组:存在冠状动脉粥样斑块CAD组,即粥样斑块组,共64例;不存在冠状动脉粥样斑块CAD组,即非粥样斑块组,共25例。采用ELISA法检测两组患者血清IL-6、sIL-6R和sgp130浓度,Spearman相关分析sgp130浓度与受累冠脉数目及Gensini评分的相关性,多因素logistic回归分析冠状动脉粥样硬化斑块病变的预测因子。结果: 粥样斑块组与非粥样斑块组在年龄、BMI、高血压、糖尿病、血脂参数上无统计学差异(P>0.05), 粥样斑块组患者男性吸烟者居多(P<0.05)。粥样斑块组血清sgp130浓度显著低于非粥样斑块组(314.97±84.39 VS 399.08±79.99 ng/ml, P<0.001),粥样斑块组血清IL-6浓度显著高于非粥样斑块组(P<0.05), 粥样斑块组血清sIL-6R浓度和C-反应蛋白浓度(CRP)与非粥样斑块组比较差异无统计学意义。多因素logistic回归分析示血清sgp130浓度是冠状动脉粥样硬化斑块病变存在的预测因子(P=0.018)。血清sgp130浓度与受累冠状动脉数目间呈负相关(r=-0.310,P=0.007),Gensini评分指数与血清sgp130浓度呈负相关(r=-0.410, P=0.001),稳定型CAD患者sgp130浓度是Gensini评分指数独立危险因素。结论:稳定型CAD患者血清sgp130浓度与冠状动脉损伤严重程度呈负相关,血清sgp130水平是冠状动脉粥样硬化严重程度血清标志物。  相似文献   

18.
Ischemic heart disease: value of MR techniques   总被引:5,自引:0,他引:5  
Background. The cardiovascular applications of magnetic resonance (MR) techniques in coronary artery disease have increased considerably in recent years. Technical advantages of MR imaging are the excellent spatial resolution, the characterization of myocardial tissue, and the potential for three-dimensional imaging. These characteristics allow the accurate assessment of left ventricular mass and volume, the differentiation of infarcted from normal tissue, and the determination of systolic wall thickening and regional wall motion abnormalities. Methods. In addition to the conventionally used spin-echo and cine-echo techniques, newer techniques such as myocardial tagging, ultrafast MR imaging and MR coronary angiography have been developed. These newer techniques allow a more accurate assessment of ventricular function (tagging), myocardial perfusion (ultrafast imaging), and evaluation of stenosis severity (MR coronary angiography). Particularly early detection and flow assessment of stenosed coronary arteries and bypasses by MR angiography would constitute a major breakthrough in cardiovascular MR imaging. Apart from the MR imaging techniques, cardiac metabolism may be well assessed using MR spectroscopy. This provides unique information on the metabolic behaviour of the myocardium under conditions stress-induced ischemia. However, the definite niche of cardiac MR spectroscopy has still to be settled. Conclusion. Currently, MR techniques allow the evaluation of anatomy and function (accepted use), perfusion and viability (development phase), and coronary angiography (experimental phase). A particular strength of MR imaging is that one single MR test may encompass cardiac anatomy, perfusion, function, metabolism and coronary angiography. The replacement of multiple diagnostic tests with one MR test may have major effects on cardiovascular healthcare economics and would outweigh the cost inherent to the MR angiography procedure.  相似文献   

19.
The study of atherosclerotic disease during its natural history and after therapeutic intervention will enhance our understanding of disease progression and regression and aid in selecting appropriate treatments. Several invasive and noninvasive imaging techniques are available to assess atherosclerotic vessels. Most of the standard techniques identify luminal diameter, stenosis, wall thickness, and plaque volume; however, none can characterize plaque composition and therefore identify the high-risk plaques. We will present the different imaging modalities that have been used for the direct assessment of the carotid, aortic, and coronary atherosclerotic plaques. We will review in detail the use of high-resolution, multicontrast magnetic resonance for the noninvasive imaging of vulnerable plaques and the characterization of plaques in terms of their various components (ie, lipid, fibrous, calcium, or thrombus).  相似文献   

20.
Coronary computed tomographic angiography (CCTA) employing CT scanners of 64-detector rows or greater represents a noninvasive method that enables accurate detection and exclusion of anatomically obstructive coronary artery disease (CAD), providing excellent diagnostic information when compared to invasive angiography. There are numerous potential advantages of CCTA beyond simply luminal stenosis assessment including quantification of atherosclerotic plaque volume as well as assessment of plaque composition, extent, location and distribution. In recent years, an array of studies has evaluated the prognostic utility of CCTA findings of CAD for the prediction of major adverse cardiac events, all-cause death and plaque instability. This prognostic information enhances risk stratification and, if properly acted upon, may improve medical therapy and/or behavioral changes that may enhance event-free survival. The goal of the present article is to summarize the current status of the prognostic utility of CCTA findings of CAD.  相似文献   

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