Coronary Atherosclerotic Plaque Vascularization Assessed by Computed Tomography

通过计算机断层扫描评估冠状动脉粥样硬化斑块血管化

• 批准号: 8445222
• 负责人: Armin A. Zadeh
• 金额: $ 19.28万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-04-01 至 2014-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8445222
• 关键词: Acute; Anatomy; Animal Model; Arterial Fatty Streak; Cardiac; Carotid Artery Plaques; Characteristics; Clinical; Coronary; Coronary Angiography; Coronary Arteriosclerosis; Coronary artery; Data; Event; Family suidae; Healthcare Systems; Histopathology; Human; Image; Image Analysis; Investigation; Lead; Magnetic Resonance Imaging; Measures; Metabolic; Methods; Myocardial Infarction; Patients; Positioning Attribute; Research; Resolution; Resources; Risk; Risk Assessment; Roentgen Rays; Slice; Technology; Testing; Tissues; Vascularization; X-Ray Computed Tomography; attenuation; density; detector; diagnostic accuracy; hypercholesterolemia; in vivo; interest; neovascularization; novel; sudden cardiac death; tool; uptake

DESCRIPTION (provided by applicant): Adequate risk assessment for acute coronary events (myocardial infarction and sudden cardiac death) is important for efficiently allocating resources for preventative measures. Advances in multi- detector computed tomography (MDCT) technology have expanded its use from traditional radiologic imaging to cardiac applications that enabled non-invasive coronary angiography with high diagnostic accuracy for detecting obstructive coronary artery disease. In addition to mere anatomic characteristics of coronary artery disease, there is immense interest in exploring the metabolic activity of coronary atherosclerotic plaque as it may inform us which plaques are or are not prone to trigger acute coronary events. An established target for assessing atherosclerotic plaque metabolic activity is the presence and extent of neovascularization within plaques. Investigations using MRI demonstrated the feasibility of detecting neovascularization in human carotid artery plaques but no data for such assessment are available in the much smaller coronary artery plaques. MDCT has superior spatial resolution compared to MRI and thus appears better positioned for detailed coronary artery imaging. We hypothesized that highly metabolically active atherosclerotic plaques will be distinct from less active plaques due to enhanced contrast uptake in tissue with greater vascularization. To test this hypothesis, we propose to image coronary arteries in an animal model using MDCT with histopathologic comparison. Specifically, we will perform MDCT in 9 pigs with induced coronary atherosclerosis and neovascularization and analyze images using a novel, normalized analysis of tissue X-ray attenuation. In a second step, we will use micro CT for ex vivo imaging of coronary arteries. Micro CT has superior spatial resolution compared to conventional MDCT but it is not available for clinical use. Micro CT may confirm our hypothesis in case MDCT fails to detect an actual difference in tissue attenuation among coronary atherosclerotic plaques of greater or lesser vascularization. Finally, we will compare the presence and degree of vascularization as detected by MDCT and micro CT with the results of histopathology. The significance of this proposal lies in the possibility of identifying a novel method for detecting coronary atherosclerotic plaques that are more metabolically active and possibly vulnerable, i.e., associated with higher coronary event risk, using tools that are widely available. This proposal, therefore, may lead to a significant advancement in our ability to identify patients at increased risk from acute coronary events which may be immediately applicable to many patients.

描述（由申请人提供）： 对急性冠脉事件（心肌梗塞和心源性猝死）进行充分的风险评估对于有效分配预防措施的资源非常重要。多探测器计算机断层扫描 (MDCT) 技术的进步已将其用途从传统放射成像扩展到心脏应用，使非侵入性冠状动脉造影能够以高诊断精度检测阻塞性冠状动脉疾病。除了冠状动脉疾病的单纯解剖特征之外，人们对探索冠状动脉粥样硬化斑块的代谢活动也产生了极大的兴趣，因为它可以告诉我们哪些斑块容易或不易引发急性冠状动脉事件。评估动脉粥样硬化斑块代谢活性的既定目标是斑块内新生血管的存在和程度。使用 MRI 进行的研究证明了检测人类颈动脉斑块中新生血管形成的可行性，但在较小的冠状动脉斑块中没有此类评估的数据。与 MRI 相比，MDCT 具有更高的空间分辨率，因此更适合详细的冠状动脉成像。我们假设，由于血管化程度较高的组织中造影剂的摄取增强，因此代谢活跃的动脉粥样硬化斑块将与活性较低的斑块不同。为了检验这一假设，我们建议使用 MDCT 对动物模型中的冠状动脉进行成像并进行组织病理学比较。具体来说，我们将对 9 头诱发冠状动脉粥样硬化和新生血管形成的猪进行 MDCT，并使用组织 X 射线衰减的新型标准化分析来分析图像。第二步，我们将使用微型 CT 进行冠状动脉离体成像。与传统 MDCT 相比，Micro CT 具有更高的空间分辨率，但尚无法用于临床。如果 MDCT 未能检测到血管化较大或较小的冠状动脉粥样硬化斑块之间组织衰减的实际差异，则微 CT 可能会证实我们的假设。最后，我们将MDCT和显微CT检测到的血管化的存在和程度与组织病理学结果进行比较。该提案的意义在于有可能确定一种新方法，使用广泛可用的工具来检测代谢更活跃且可能更脆弱（即与更高的冠状动脉事件风险相关）的冠状动脉粥样硬化斑块。因此，这一提议可能会大大提高我们识别急性冠状动脉事件风险增加的患者的能力，这可能会立即适用于许多患者。