冠状动脉粥样硬化斑块及其影像学评价

冠状动脉粥样硬化斑块易发生腐蚀和破裂，导致冠状动脉急性闭塞，引起急性心肌梗塞。有效评价斑块的结构特点，监测其演变过程，对选择治疗时机和治疗方案有重要价值。综述了冠状动脉粥样硬化斑块概念，病理特点和演变规律，评价各种影像技术包括血管内超声，多层CT和磁共振成像对其诊断的价值和限度。     

冠状动脉粥样硬化斑块及其影像学评价

冠状动脉粥样硬化斑块易发生腐蚀和破裂,导致冠状动脉急性闭塞,引起急性心肌梗塞.有效评价斑块的结构特点,监测其演变过程,对选择治疗时机和治疗方案有重要价值.综述了冠状动脉粥样硬化斑块概念,病理特点和演变规律,评价各种影像技术包括血管内超声,多层CT和磁共振成像对其诊断的价值和限度.     

磁共振评价冠状动脉粥样硬化斑块的研究进展

有研究表明,导致管腔狭窄程度小于50%的粥样硬化斑块由于重构效应,冠状动脉造影常难以发现,而这种粥样斑块可能为易损斑块。冠状动脉易损斑块破裂是造成急性冠脉事件的重要原因。目前,尚缺乏无创性影像学方法评价冠状动脉斑块成分。本文就磁共振成像评价冠状动脉粥样硬化斑块的研究进展进行综述。     

64层CT评价冠脉粥样斑块性质与狭窄程度的相关性

目的：探讨64层CT评价冠状动脉粥样硬化斑块性质与冠脉狭窄程度之间的相关性。方法：36例疑诊为冠心病患者行64层冠状动脉CT血管成像（CCTA）及冠状动脉血管造影（CAG）检查,以CAG为标准评价CCTA诊断冠脉狭窄程度的准确性,并诊断冠状动脉粥样硬化斑块性质,分析其与经CAG确诊的冠脉狭窄程度之间有无统计学意义。结果：36例患者中共检出105个斑块。冠脉轻度狭窄以钙化斑块引起为主,冠脉中度狭窄和重度狭窄以混合斑块引起为主。CCTA诊断冠状动脉钙化斑块与管腔轻度狭窄、混合斑块与中重度管腔狭窄存在相关性。结论：64层CCTA可在诊断冠脉狭窄的同时无创性评价斑块性质,可及时发现冠脉中脂质成分丰富的斑块,以便尽早及时给予临床干预,可降低急性冠脉综合征发生率。     

血管内超声对冠状动脉粥样硬化斑块性质的识别

冠状动脉粥样硬化斑块的破裂是急性冠脉综合征的始动环节,因此,对于斑块性质进行判断,如何识别易破裂斑块成为摆在我们面前的一大课题。本研究旨在探讨血管内超声（Intravascular ultrasound,IVUS）在识别冠状动脉粥样硬化斑块性质方面的应用价值。     

颈动脉粥样硬化与冠状动脉狭窄分级的关系

目的:探讨颈动脉粥样硬化与冠状动脉粥样硬化的关系。材料和方法:选取行颈动脉超声和冠状动脉造影检查的受检者367例,根据冠状动脉造影及颈动脉超声结果将受检者分为冠状动脉正常组、狭窄组和颈动脉无斑块组、单侧及双侧斑块组,分别测量冠状动脉狭窄程度和颈总动脉内—中膜厚度(IMT),并分析两者之间的关系。结果:随着冠状动脉粥样硬化病变支数的增加和狭窄程度的加重,颈动脉斑块检出率增加,IMT增厚;随着颈动脉斑块检出部位的增加冠状动脉狭窄的严重程度增加。结论:颈动脉粥样硬化的程度和累及部位的多少与冠状动脉病变支数及狭窄程度密切相关。     

冠状动脉粥样硬化斑块的影像学诊断进展

冠心病诊断的“金标准”冠状动脉造影只能判断冠状动脉管腔的狭窄程度，而冠状动脉发生狭窄以前冠状动脉壁的粥样硬化斑块病变已存在很长一段时间，这时病人可能已经表现有冠心病的症状，并且可能发生心肌梗塞和心脏性猝死等急性临床综合征。检测冠状动脉壁的粥样硬化斑块病变具有重要意义。     

冠状动脉粥样硬化斑块稳定性评价的影像学进展

急性冠状动脉综合征(acute coronary syndromes,ACS)包括不稳定心绞痛、急性心肌梗死和心源性猝死,是导致冠心病患者死亡的主要因素.目前认为,60%～70 %的ACS患者发病前冠状动脉病变并不严重,其发生原因主要是由于冠状动脉粥样硬化斑块破裂或裂隙形成,导致血栓形成和血管收缩[1].因此,对斑块稳定性的显像研究成为目前倍受关注的热点,以求早期采取必要的措施控制动脉粥样硬化的进一步发展,从而提高患者的生存质量.笔者综述各种影像技术在冠状动脉斑块诊断中的优势和不足,尤其是评估斑块稳定性的敏感检查方法及各种影响因素.     

Characteristics of Atheromatous Plaque in Coronary Artery in Angina Patients with Diabetes Using 64 Slice Spiral CT Angiography

目的 利用MSCT血管造影探讨合并糖尿病的心绞痛患者冠状动脉粥样硬化斑块特点. 资料与方法 以接受64排螺旋CT冠状动脉造影检查的心绞痛患者60例为研究对象,其中合并糖尿病者30例,无糖尿病者30例.观察并比较两组患者的冠状动脉粥样硬化斑块的分布特点与类型特点.结果 与非糖尿病组相比,糖尿病组具有更多的混合斑块.经年龄和性别调整后,糖尿病是混合斑块的独立危险因素.结论 MSCT冠状动脉造影能够准确反映动脉粥样硬化斑块在糖尿病和非糖尿病患者之间的差异,合并糖尿病的心绞痛患者由于混合斑块的增加而处于易发心血管事件的高危状态.     

256排螺旋CT在冠状动脉粥样硬化病变中的诊断价值

冠状动脉粥样硬化是造成冠状动脉粥样硬化性心脏病(冠心病)的最常见病因,是指由于脂质代谢不正常,血液中的脂质沉着在原本光滑的动脉内膜上,在动脉内膜一些类似粥样的脂类物质堆积而成白色斑块,称为动脉粥样硬化病变[1].这些斑块渐渐增多造成动脉腔狭窄,使血流受阻,导致心脏缺血,从而引发心绞痛.但动脉粥样硬化的病因尚未完全阐明,主要危险因素为高血压、高血脂和吸烟.其他危险因素有年龄、性别、不平衡膳食、糖尿病、肥胖、缺少运动和精神压力.由于慢性内皮损伤和各种危险因素造成血管壁对脂质和单核巨噬细胞通透性增加以及平滑肌细胞增生从而产生粥样硬化斑块.     

多层螺旋CT在评价冠状动脉斑块中的临床应用

目的：探讨多层螺旋CT在评价冠状动脉粥样斑块的价值.方法：对 72例患者进行多层螺旋CT冠状动脉造影,对强化扫描获得的轴位图像利用后处理软件进行VR、MIP、CPR、薄层VR重建,评价冠脉斑块,并对冠脉有否狭窄及狭窄程度进行诊断.结果 ：MSCT冠状动脉检查诊断硬斑块、中间斑块和软斑块分别56支、10支和20支,同时可对冠脉主干的狭窄程度进行评判,本组病例冠状动脉各主干轻度狭窄、中度狭窄和重度狭窄分别为38支、20支及28 支.结论：MSCT冠脉造影检查是一种微创的冠脉检查方法,它不但可以发现粥样斑块,而且能鉴别冠脉斑块的性质,并能显示冠状动脉的狭窄及狭窄程度,是冠状动脉检查的一种比较可靠的检查方法.     

颈动脉超声在40岁以上飞行员体检中对冠心病的诊断价值

目的：提高对冠心病的认识,预防冠心病的发生,及早干预以确保飞行安全,延长飞行年限。方法对53例40岁以上的飞机驾驶员进行颈动脉超声的检查,针对超声诊断为动脉斑块形成的飞机驾驶员进行进一步检查,包括64排冠脉螺旋CT／冠脉造影,以初步筛查冠心病。结果53例中,颈动脉斑块形成的有3例,此3例中诊断为冠心病的有1例,诊断为冠状动脉肌桥形成的有1例。结论通过颈动脉超声检测颅外段颈动脉的斑块的形成、检测有无狭窄和阻塞对冠心病发生发展有着良好的预测价值。     

320-DVCT在评估多个血液因子与冠状动脉硬化相关性中的应用

目的 通过320排动态容积CT (320-DVCT)检查来评估高敏C反应蛋白(hs-CRP)、血清总胆红素(Tbil)和血尿酸(BUA)对检测冠状动脉粥样硬化程度的临床价值.方法 入选160例稳定型心绞痛患者,进行320-DVCT冠状动脉成像,根据CT值将病变血管处斑块分为软斑块、纤维斑块、钙化斑块,同时检测患者hs-CRP、血清Tbil和BUA浓度,明确3项指标对冠状动脉病变支数、斑块性质及狭窄程度的诊断意义.对照组为100例健康者.结果 冠心病患者随着hs-CRP、BUA浓度的升高,Tbil的浓度降低,冠状动脉病变支数及狭窄程度加重,且更容易形成软斑块.结论 通过320-DVCT检查证实了hs-CRP、血清Tbil和BUA能准确评判冠心病患者冠状动脉病变支数、斑块性质及狭窄程度,有利于对冠状动脉粥样硬化进行风险评估.     

Coronary plaque imaging by coronary computed tomography angiography

Coronary computed tomography angiography (CTA) has become the useful noninvasive imaging modality alternative to the invasive coronary angiography for detecting coronary artery stenoses in patients with suspected coronary artery disease (CAD). With the development of technical aspects of coronary CTA, clinical practice and research are increasingly shifting toward defining the clinical implication of plaque morphology and patients outcomes by coronary CTA. In this review we discuss the coronary plaque morphology estimated by CTA beyond coronary angiography including the comparison to the currently available other imaging modalities used to examine morphological characteristics of the atherosclerotic plaque. Furthermore, this review underlies the value of a combined assessment of coronary anatomy and myocardial perfusion in patients with CAD, and adds to an increasing body of evidence suggesting an added diagnostic value when combining both modalities. We hope that an integrated, multi-modality imaging approach will become the gold standard for noninvasive evaluation of coronary plaque morphology and outcome data in clinical practice.     

Computational fluid dynamics in coronary artery disease

Computational fluid dynamics (CFD) is a widely used method in mechanical engineering to solve complex problems by analysing fluid flow, heat transfer, and associated phenomena by using computer simulations. In recent years, CFD has been increasingly used in biomedical research of coronary artery disease because of its high performance hardware and software. CFD techniques have been applied to study cardiovascular haemodynamics through simulation tools to predict the behaviour of circulatory blood flow in the human body. CFD simulation based on 3D luminal reconstructions can be used to analyse the local flow fields and flow profiling due to changes of coronary artery geometry, thus, identifying risk factors for development and progression of coronary artery disease. This review aims to provide an overview of the CFD applications in coronary artery disease, including biomechanics of atherosclerotic plaques, plaque progression and rupture; regional haemodynamics relative to plaque location and composition. A critical appraisal is given to a more recently developed application, fractional flow reserve based on CFD computation with regard to its diagnostic accuracy in the detection of haemodynamically significant coronary artery disease.     

hs-CRP联合颈动脉斑块检测对冠心病的预测意义

目的探讨高敏C反应蛋白（hs-CRP）联合颈动脉斑块对冠心病的预测价值。方法将140例观察对象分为对照组30例、稳定型心绞痛组（SA组）40例、急性冠脉综合征（ACS）组70例[不稳定型心绞痛组（UA组）50例和急性心肌梗死组（AMI组）20例],所有患者均行体表颈动脉超声检查（包括颈动脉内膜中层厚度、斑块情况）、冠脉造影和血清高敏C反应蛋白（hs—CRP）,比较3组患者颈动脉斑块情况、冠状动脉病变情况及血清高敏C反应蛋白（hs—CRP）水平。结果与对照组相比,冠心病组患者颈动脉斑块发生率较高;ACS组hs—CRP水平明显高于SAP组和对照组。结论hs—CRP水平有助于冠状动脉内不稳定斑块的预测;颈动脉斑块有助于冠脉斑块的预测．颈动脉斑块联合hs—CRP对急性冠脉综合征有一定的预测意义。     

Quantitative assessment of atherosclerotic plaque,recent progress and current limitations

An important advantage of computed tomography coronary angiography (CCTA) is its ability to visualize the presence and severity of atherosclerotic plaque, rather than just assessing coronary artery stenoses. Until recently, assessment of plaque subtypes on CCTA relied on visual assessment of the extent of calcified/non-calcified plaque, or visually identifying high-risk plaque characteristics. Recent software developments facilitate the quantitative assessment of plaque volume or burden on CCTA, and the identification of subtypes of plaque based on their attenuation density. These techniques have shown promise in single and multicenter studies, demonstrating that the amount and type of plaque are associated with subsequent cardiac events. However, there are a number of limitations to the application of these techniques, including the limitations imposed by the spatial resolution of current CT scanners, challenges from variations between reconstruction algorithms, and the additional time to perform these assessments. At present, these are a valuable research technique, but not yet part of routine clinical practice. Future advances that improve CT resolution, standardize acquisition techniques and reconstruction algorithms and automate image analysis will improve the clinical utility of these techniques. This review will discuss the technical aspects of quantitative plaque analysis and present pro and con arguments for the routine use of quantitative plaque analysis on CCTA.     

Measuring Progression of Coronary Atherosclerosis with Computed Tomography: Searching for Clarity Among Shades of Gray

Computed tomography (CT) allows visualization of both calcified and noncalcified atherosclerotic plaque in the entire coronary tree. When assessing an individual patient's risk of cardiac events, direct visualization of coronary plaque has substantial advantages over assessment of surrogate markers or risk factors. Ideally, practitioners would be able to follow progression or regression of coronary disease via quantitative measurements of plaque volume and composition in individual patients. Once this is possible, CT could be used to: (1) make more informed decisions about whether and how aggressively to treat patients at risk for coronary artery disease, and (2) to follow the effects of treatment in patients with known coronary artery disease. At this point in time, coronary calcium scoring is more reproducible than CT angiography for quantifying plaque and also has a much larger body of evidence supporting its ability to predict cardiac events. In this paper we will review the current techniques for quantifying calcified and noncalcified coronary atherosclerosis with cardiac CT, the strengths and limitations of each approach and the data supporting the ability to quantify and follow progression or regression of plaque.     

冠心病治疗前后颈动脉硬化斑块及内中膜厚度的变化

目的探讨冠心病患者治疗前后,颈动脉硬化斑块及颈动脉内中膜厚度（IMT）的变化,了解冠心病与颈动脉硬化斑块间的相关性,为防治冠心病提供有关诊疗依据。方法选择经冠状动脉造影检查诊断患有冠心病,同时经颈动脉超声检查明确伴有颈动脉硬化斑块及IMT异常的冠心病患者240例为对象,按冠心病常规药物治疗,定期做颈动脉B超检查,对比治疗前后颈动脉硬化斑块及IMT的变化情况。结果治疗6、12个月,总胆固醇和低密度脂蛋白均较治疗前显著降低（P〈0.05或P〈0.01）,颈动脉IMT、颈动脉斑块数和斑块的总面积改善情况与治疗前比较,均有非常显著性差异（P〈0.01）。结论冠心病经治疗后,颈动脉硬化斑块及颈动脉IMT随之明显改善,冠状动脉硬化与颈动脉硬化的发病和治疗转归关系密切。