易损斑块的分子病理学研究进展

急性冠脉综合征是心血管内科常见重症，冠状动脉粥样硬化斑块的破裂伴继发血栓形成是其最常见病理学机制，这种易于破裂而导致不良心脏事件的斑块即为易损斑块，其形成及破裂并最终引起急性冠脉综合征的过程中有许多细胞和分子的参与，本文就易损斑块的形态学特征和斑块稳定性的分子病理学机制作一概述。     

易损斑块的血清炎症标志物的研究进展

急性冠状动脉综合征是严重威胁人类健康的一种常见病和多发病。急性冠状动脉综合征的病理基础是由于易损斑块的存在,且易损斑块的破裂是急性冠状动脉综合征发生的始动环节。现有临床检测方法仅能监测到急性冠脉事件发生的当时及事后血清学变化,而早期发现易损斑块,及时进行干预,对降低急性冠状动脉综合征的发病率和死亡率具有极其重要的临床意义。现主要就检测易损斑块的血清炎症标志物的研究进展作一综述。     

易损斑块与急性冠脉综合征

斑块稳定性是影响急性冠脉综合征发生与发展的主要决定性因素,临床上,易损斑块破裂并发血栓形成被视为急性冠脉综合征的病理学基础。     

急性冠脉综合征易损斑块的研究进展

易损斑块在急性冠脉综合征(ACS)的发病及进展过程中起到重要作用,其发病机制和早期诊断是研究的热点。本文阐述了易损斑块(vulnerable plaque)的病理学特征、致病机制及相关影响因素,并对目前有创和无创影像学技术对易损斑块的早期识别的最新进展、易损斑块的血清标记物研究及易损斑块的早期干预治疗进行了综述。     

光学相干断层成像对急性冠状动脉综合征患者易损斑块的新认识

血管斑块的稳定性是影响急性冠状动脉综合征发生发展的主要因素,具有超高空间分辨率的光学相干断层成像(OCT)技术在易损斑块识别方面有着独特的优势。本文就近年来OCT在急性冠状动脉综合征患者易损斑块识别方面的临床新进展进行综述。     

高危和易损冠脉斑块的命名

2003年6月17～18日在希腊召开会议，讨论高危／易损粥样斑块患者易发生急性冠脉综合征(ACS)。会议提出对改进诊断方法，识别易患患者的重要性，随着对冠脉血栓形成病理生理学认识的增加，对斑块需进行统一命名，如下。     

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。     

急性冠脉综合征易损斑块的发病机理与早期检测

急性冠状动脉综合征（Acute coronary syndrome,ACS）是临床常见的急性心血管病之一,具有很高的致死率和致残率,采取有效措施及早发现冠状动脉粥样硬化病变和识别易损斑块,并据此制定相应策略积极干预缺血前状态,已成为当前的研究热点.本文对冠状动脉易损斑块的发病机理及主要检测手段做一简要综述.     

急性冠状动脉综合征患者白细胞介素-18的变化及其临床意义

急性冠状动脉综合征的发生发展与动脉粥样硬化斑块的稳定性密切相关,易损斑块的破裂被认为是急性冠状动脉综合征的主要发病机制。目前研究认为动脉粥样硬化是慢性炎症疾病,越来越多的证据支持炎症反应在动脉粥样硬化的发生发展中起到重要作用。白细胞介素-18是近年来发现的一个促炎细胞因子,其在急性冠状动脉综合征粥样斑块易损性方面发挥了重要作用.并对急性冠状动脉综合征患者的早期诊断和冠状动脉病变的严重程度及对心血管终末事件的发生的预测有重要的临床意义。     

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…     

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。     

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。     

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。     

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.     

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.     

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.     

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.     

Current status of vulnerable plaque detection

Critical coronary stenoses have been shown to contribute to only a minority of acute coronary syndromes (ACS) and sudden cardiac death. Autopsy studies have identified a subgroup of high‐risk patients with disrupted vulnerable plaque and modest stenosis. Consequently, a clinical need exists to develop methods to identify these plaques prospectively before disruption and clinical expression of disease. Recent advances in invasive and noninvasive imaging techniques have shown the potential to identify these high‐risk plaques. The anatomical characteristics of the vulnerable plaque such as thin cap fibroatheroma and lipid pool can be identified with angioscopy, high frequency intravascular ultrasound, intravascular MRI, and optical coherence tomography. Efforts have also been made to recognize active inflammation in high‐risk plaques using intravascular thermography. Plaque chemical composition by measuring electromagnetic radiation using spectroscopy is also an emerging technology to detect vulnerable plaques. Noninvasive imaging with MRI, CT, and PET also holds the potential to differentiate between low and high‐risk plaques. However, at present none of these imaging modalities are able to detect vulnerable plaque neither has been shown to definitively predict outcome. Nevertheless in contrast, there has been a parallel development in the physiological assessment of advanced atherosclerotic coronary artery disease. Thus recent trials using fractional flow reserve in patients with modest non flow‐limiting stenoses have shown that deferral of PCI with optimal medical therapy in these patients is superior to coronary intervention. Further trials are needed to provide more information regarding the natural history of high‐risk but non flow‐limiting plaque to establish patient‐specific targeted therapy and to refine plaque stabilizing strategies in the future. © 2009 Wiley‐Liss, Inc.     

四项指标与冠心病冠脉病变和易损斑块的相关性及其应用价值

目的 探讨四项指标即脂蛋白相关磷脂酶 A2（Lp-PLA2）、D-二聚体(D-D)、纤维蛋白原(Fg)及D-D与Fg的比值（D/F）与冠心病冠脉病变程度和易损斑块的相关性。 方法 选取2018年1月～2020年8月廊坊市第四人民医院收治的因胸痛或胸闷入院的冠心病患者110例为研究对象。根据冠脉病变程度将冠心病患者分为轻度病变组(n=49)、中度病变组(n=32) 例和重度病变组(n=29),对照组为同期体检健康志愿者(n=50) 。根据血管内超声（IVUS）检查结果分为稳定斑块组(n=57)和易损斑块组(n=53)例。比较不同冠脉病变程度组的四项指标及稳定斑块组和易损斑块组特征性指标的差异。分别采用 Pearson 相关系数和ROC曲线评价四项指标与冠脉病变和易损斑块的相关性和预测效能。采用多变量Logistic 逐步回归分析冠脉病变和易损斑块的危险因素,并评价其应用价值。 结果 冠心病各亚组Lp-PLA2、D-D、Fg、D/F及Gensini 积分均显著高于对照组（P<0.05）,不同冠脉病变程度组以上指标比较,差异亦有统计学意义（P<0.05）。易损斑块组斑块负荷、血管重塑指数、偏心指数高于稳定斑块组（P<0.05）,纤维帽厚度低于稳定斑块组（P<0.05）。Pearson 相关分析显示,Lp-PLA2、D-D、Fg、D/F与冠脉Gensini 积分及斑块负荷、血管重塑指数、偏心指数呈正相关（P<0.05）,与纤维帽厚度呈负相关（P<0.05）。多变量Logistic逐步回归分析显示,Lp-PLA2、D-D、Fg、D/F为冠脉中重度病变和易损斑块的独立危险因素。ROC曲线显示,Lp-PLA2、D-D、Fg、D/F联合预测中重度病变和易损斑块的AUC大于各项指标单独检测的AUC（P<0.05）。 结论 冠心病患者Lp-PLA2、D-D、Fg、D/F与冠脉病变程度和斑块易损性密切相关,有可能成为预测冠脉病变和易损斑块的可靠标志物。