微观结构在易损斑块进展中的作用

急性冠状动脉综合征常常导致严重的心血管事件,而冠状动脉粥样硬化斑块破裂是绝大多数急性冠状动脉综合征发生的原因,因此检测高破裂风险的易损斑块,对筛选和干预急性冠状动脉综合征具有重要意义。随着研究的不断进展,易损斑块内的一些微观结构如斑块内新生血管、微小钙化、胆固醇结晶,在易损斑块的进展中起到重要的作用。因此,本文以易损斑块内最常见的3种微观结构为重点,综述斑块内微观结构在易损斑块进展中的作用。     

动脉粥样硬化蚀损斑块合并血栓形成研究进展

急性冠状动脉综合征和心脏缺血性猝死是严重影响人类健康的重大疾病,其病理基础包括易损斑块、易损心肌和易损血液。根据尸检结果,易损斑块的病理分型包括破裂斑块、蚀损斑块（又称糜烂斑块）（eroded plaque／plaqueerosion）和钙化结节等”。其中,破裂斑块最为常见,约占易损斑块70％,目前对其机制研究已广泛且深入”。但是,有关蚀损斑块机制的研究,目前国内未见。     

易损斑块的病理生理机制及其检测的研究进展

随着对急性冠状动脉综合征(ACS)病理生理机制的深入研究,目前对易损动脉粥样硬化斑块(简称:易损斑块)有了新的理解。认识易损斑块的内在特性和破裂机制,对于早期检测和处理易损斑块具有重要的临床意义。本文就易损斑块的概念、基本特征、病理生理机制及其检测作一论述。一、易损斑块的最新概念从病理生理角度来讲,ACS最主要的深层原因是易损斑块。易损斑块是指那些不稳定和有血栓形成倾向的斑块,主要包括破裂斑块、侵蚀性斑块和部分钙化结节性病变[1] 。大量的研究表明,约70 %～80 %的ACS是由于轻、中度狭窄的冠状动脉斑块的破裂、继发…     

急性冠状动脉综合征患者血清脂联素及高分子量脂联素浓度与罪犯病变虚拟组织学-血管内超声的特点

目的:探讨血清脂联素及高分子量脂联素浓度随冠状动脉(冠脉)粥样硬化性斑块构成变化而变化的现象,为进一步研究影响冠脉斑块易损性的机制提供依据。方法:选取急性冠脉综合征(ACS)患者60例,运用酶联免疫分析法(ELISA)检测血清脂联素及高分子量脂联素的浓度。结合ST段及T波发生改变的导联,室壁运动异常的节段,复杂病变的部位及斑块破裂与否来综合确定罪犯病变。研究ACS患者血清脂联素及高分子量脂联素浓度与罪犯病变罪犯病变虚拟组织学-血管内超声(VH-IVUS)特点的相关性。结果:ACS患者血清高分子量脂联素与罪犯病变纤维脂质体积绝对值呈中等程度相关(r=0.505,P0.01),与罪犯病变纤维组织体积绝对值亦呈正相关(r=0.499,P0.01),而ACS患者血清脂联素与罪犯病变4种VH-IVUS检测的成分间无相关性。结论:ACS患者罪犯病变斑块相对稳定的成分纤维组织和纤维脂质含量增加时,血清高分子量脂联素也增加。高分子量脂联素作为保护性的脂肪因子可能参与到影响冠脉斑块易损性的机制。     

冠状动脉易损斑块的影像学诊断进展

冠状动脉易损斑块的破裂是急性冠状动脉综合征的重要发病环节,早期发现、识别冠状动脉易损斑块对于降低恶性心血管事件的发生率,指导临床决策及改善预后都具有重要意义。近年来许多影像学技术应用于冠状动脉易损斑块的识别,现分析各种影像学技术在冠状动脉易损斑块诊断方面的成像特点、临床价值及发展现状。     

有关血管紧张素转换酶抑制剂的一些新老问题(续前)

2.8 稳定动脉斑块 血管紧张素Ⅱ(angiotensinⅡ,AngⅡ)可以刺激内皮素释放.内皮素是一种最强的冠状动脉收缩因子,在冠状动脉易损斑块存在的前提下,内皮素的释放可能会导致斑块破裂.低镁血症能引起冠状动脉血管反应性增加,促进斑块破裂.AngⅡ能够导致与镁缺乏相关的多种变化,包括诱导促氧化剂和促炎因子的生成.     

动脉粥样硬化易损斑块的动物模型和检测技术

动脉粥样硬化易损斑块破裂、血栓形成是急性冠状动脉综合征的发病机制已成为共识。由于缺乏理想的易损斑块的动物模型,对斑块破裂前的血清学及影像学特征研究较少,尚缺乏能够早期识别易损斑块及预防斑块破裂的最佳方法。本实验室已成功构建家兔和Apo E-/-小鼠的易损斑块模型。易损斑块的检测技术主要包括非侵入性及侵入性的影像学检测及功能学检测技术。对易损斑块的早期准确识别以便及时干预具有十分重要的临床意义。     

冠状动脉CT成像与易损斑块

冠状动脉内斑块破裂或侵蚀所致的急性腔内血栓是急性冠状动脉综合征的主要原因。防止急性血栓形成成为了降低冠状动脉粥样硬化性心脏病病死率的唯一有效策略。斑块易破裂的冠状动脉病变与稳定斑块相比,存在不同的形态学改变。因此可以利用特殊的成像方法来识别这些易损斑块。亚毫米空间分辨率和图像质量优良的现代计算机断层扫描方法可以对冠状动脉斑块进行检测、分析和量化。斑块体积较大、低CT衰减、餐巾环征、正性重构以及点状钙化等与斑块容易破裂有密切关系。将冠状动脉斑块的形态学与功能特征等相结合,在未来有可能成为检测易损斑块的新方法。现将就多层螺旋CT与冠状动脉易损斑块的检测做一综述。     

易损斑块的诊断进展

急性冠状动脉综合征患者具有较高的发病率,预后较差,而冠状动脉内易损斑块破裂伴随血栓形成是其主要原因.因此早期正确诊断易损斑块,对于急性冠脉综合征的防治具有重大意义.现就易损斑块的诊断进展作一综述.     

多层螺旋CT评价血脂康治疗稳定冠状动脉易损斑块的价值

冠状动脉粥样硬化性心脏病(CHD)是目前危害人类健康的最主要疾病之一,研究结果表明,冠状动脉粥样硬化易损斑块破裂,引发血小板聚集、血栓形成及冠状动脉急性闭塞是急性冠状动脉综合征的发病机制.因此,稳定甚至消退易损斑块,成为防止急性冠状动脉事件发生的重要目标.血脂康是中药红曲提取物,包含有以洛伐他汀为主的多种他汀及不饱和脂肪酸、生物碱、甾醇类及少量黄酮类物质[1],已有研究结果表明血脂康能够降低冠心病患者相关事件的危险性[2],提示其可能具有稳定易损斑块的作用.     

Molecular imaging of plaques in coronary arteries with PET and SPECT

Coronary artery disease remains a major cause of mortality. Presence of atherosclerotic plaques in the coronary artery is responsible for lu-men stenosis which is often used as an indicator for determining the severity of coronary artery disease. However, the degree of coronary lumen stenosis is not often related to compromising myocardial blood flow, as most of the cardiac events that are caused by atherosclerotic plaques are the result of vulnerable plaques which are prone to rupture. Thus, identification of vulnerable plaques in coronary arteries has become increas-ingly important to assist identify patients with high cardiovascular risks. Molecular imaging with use of positron emission tomography （PET） and single photon emission computed tomography （SPECT） has fulfilled this goal by providing functional information about plaque activity which enables accurate assessment of plaque stability. This review article provides an overview of diagnostic applications of molecular imaging tech-niques in the detection of plaques in coronary arteries with PET and SPECT. New radiopharmaceuticals used in the molecular imaging of coro-nary plaques and diagnostic applications of integrated PET/CT and PET/MRI in coronary plaques are also discussed.     

冠状动脉粥样硬化斑块温度异质性及其检测的研究进展

冠状动脉易损斑块的破裂与急性冠脉综合征密切相关,目前对易损斑块的检测有多种方法,包括有创性和无创性检测。研究发现动脉粥样硬化斑块表面的温度与正常血管壁的温度有差异,不同的动脉粥样硬化斑块依据其易损程度的不同其温度异质性也不同。冠状动脉内温度导丝测定仪利用该原理检测斑块表面温度异质性,间接判断动脉粥样硬化斑块的组成和易损程度。     

冠状动脉CT血管造影综合评估易损斑块的进展

急性冠状动脉综合征（ACS）是以冠状动脉粥样硬化斑块破裂或侵袭,继发完全或不完全闭塞性血栓形成为病理基础的一组临床综合征。与稳定斑块相比,容易破裂的斑块具有明显的影像学特征：大斑块体积,低衰减斑块,餐巾指环标志,正性重构和点状钙化,这为在导致临床事件之前运用非侵入性成像识别易损斑块提供了独特的机会。随着影像技术的发展,冠状动脉CT 血管造影（CCTA）无创性评价冠状动脉易损斑块的作用已成为国内外研究热点。笔者就CCTA在评估冠状动脉斑块易损性方面的临床应用现状与进展等方面作一综述。     

Evaluation of plaque morphology by coronary CT angiography

Coronary computed tomographic angiography (CTA) is a promising noninvasive tool that allows the visualization of plaque morphology. Plaques characterized by positive remodeling, low attenuation, and napkin ring circular enhancement on contrast-enhanced coronary CTA have been regarded as rupture-prone vulnerable plaques, which account for about 60% of all vulnerable lesions and may be precursors of plaque rupture. In this article, the authors discuss the various features related to plaque morphology that are essential to detect vulnerable plaques while performing coronary CTA.     

Recent advances in coronary angioscopy

Angioscopy enables macroscopic pathological diagnosis of cardiovascular diseases from the inside. This imaging modality has been intensively directed to characterizing vulnerable coronary plaques. Scoring of plaque color was developed, and based on prospective studies; dark yellow or glistening yellow plaques were proposed as vulnerable ones. Colorimetry apparatus was developed to assess the yellow color of the plaques quantitatively. The effects of lipid-lowering therapies on coronary plaques were confirmed by angioscopy. However, since observation is limited to surface color and morphology, pitfalls of this imaging technology became evident. Dye-staining angioscopy and near-infrared fluorescence angioscopy were developed for molecular imaging, and the latter method was successfully applied to patients. Color fluorescence angioscopy was also established for molecular and chemical basis characterization of vulnerable coronary plaques in both in vitro and in vivo. Drug-eluting stents (DES) reduce coronary restenosis significantly, however, late stent thrombosis (LST) occurs, which requires long-term antiplatelet therapy. Angioscopic grading of neointimal coverage of coronary stent struts was established, and it was revealed that neointimal formation is incomplete and prevalence of LST is higher in DES when compared to bare-metal stent. Many new stents were devised and they are now under experimental or clinical investigations to overcome the shortcomings of the stents that have been employed clinically. Endothelial cells are highly anti-thrombotic. Neoendothelial cell damage is considered to be caused by friction between the cells and stent struts due to the thin neointima between them that might act as a cushion. Therefore, development of a DES that causes an appropriate thickness (around 100 μm) of the neointima is a potential option with which to prevent neoendothelial cell damage and consequent LST while preventing restenosis.     

Update on coronary angioscopy: review of a 20-year experience and potential application for detection of vulnerable plaque

Predicting the occurrence of future acute coronary syndromes remains an important challenge of contemporary cardiology. It is thought that detecting the individual vulnerable plaques in patients can be an important step to preventing myocardial infarction and sudden cardiac death. Coronary angioscopy can provide detailed information of the luminal surface of plaque, such as color, thrombus, or disruption, and is one of a few possibly useful imaging modalities for identifying vulnerable plaques. During its 20-year history, coronary angioscopy has been used as a diagnostic tool or to guide coronary angioplasty, and has contributed to our understanding of the pathophysiology of coronary artery disease. Yellow plaques seen during angioscopy seem to have many characteristics of high risk or vulnerable plaques, most consistent with the thin-cap fibroatheroma. Moreover, differences in yellow color have been reported to reflect differences in the structure or composition of plaques. Development of quantitative methods to assess plaque color and histopathologic correlations in conjunction with prospective natural history studies may lead to advances in vulnerable plaque detection by coronary angioscopy. Although current angioscopic devices are limited by the need to displace the column of blood in order to see the vessel wall, and by the lack of quantitative colorimetric methods, advances in technology may lead to new device versions that could be practical for expanded clinical use.     

The current and future role of percutaneous coronary intervention in patients with coronary artery disease

With increasing research on vulnerable plaques and uncertainty regarding which lesions require revascularization, the goal of this review is to clarify the indications for percutaneous coronary intervention and discuss which lesions do not warrant treatment by intervention. This paper also briefly reviews the potential advantages and limitations of technology that may enable detection of atherosclerotic plaques that are prone to rupture and discusses the future utility of these technologies in prevention of acute coronary syndromes. Providing an evidence-based understanding of lesion morphology and clinical variables that influence outcome enables the interventional cardiologist to determine which atherosclerotic plaques require PCI.     

中国人群脂蛋白a与冠状动脉易损斑块相关性的Meta分析

目的：系统评价脂蛋白a[Lipoprotein a, Lp （a）]对冠状动脉易损斑块的预测价值。方法：以脂蛋白a、易损斑块、不稳定斑块、冠状动脉、冠心病、Lipoprotein a、Lipoprotein (a)、vulnerable plaque、unstable plaque、coronary vessel、coronary artery、coronary heart disease、coronary disease等为检索词,检索PubMed,Embase,Cochrane Library,CNKI,CBM以及万方平台从建库到2020年7月的关于Lp （a）与冠脉易损斑块相关性的临床试验研究,。采用NOS质量评分量表对文献进行质量评价,应用RevMan 5.3软件及Stata 12.0软件对纳入的文献进行Meta分析。结果：经筛选后最终纳入文献11篇,1351名患者,易损斑块组717人,稳定斑块组634人。Meta分析结果显示：易损斑块组中患者血清Lp （a）水平较稳定斑块组明显升高（SMD=1.27,95%CI：0.77,1.77）。结论：人血清中Lp （a）可能是冠状动脉易损斑块形成的重要危险因素,其含量的升高可能具有预测急性心血管事件发生的能力。     

Imaging of the vulnerable plaque: noninvasive and invasive techniques

In a large proportion of previously asymptomatic individuals, sudden coronary death or acute myocardial infarction occurs as the first manifestation of coronary atherosclerosis. Imaging of coronary atheromatous plaques has traditionally centered on assessing the degree of luminal stenosis. The angiographic techniques that are routinely used to identify stenotic atherosclerotic lesions are unable to identify high-risk plaques; plaques prone to rupture and cause a cardiovascular event. This is partly due to the fact that the majority of culprit lesions that produce acute cardiovascular syndromes are not severely stenotic, possibly due to significant positive remodeling and reduced protective collateral circulation as well as because the risk of plaque rupture is more closely related to plaque content than plaque size. Recently, the focus of new imaging techniques is to identify the high risk plaques; the "vulnerable plaques." In this review, we will refer to the noninvasive and invasive techniques that can detect the vulnerable plaque.