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: 8278878
• 负责人: Armin A. Zadeh
• 金额: $ 24.3万
• 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/8278878
• 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. PUBLIC HEALTH RELEVANCE: This research intends to develop a method for characterizing the biologic activity of plaque in heart arteries seen by computed tomography (CT). The methods proposed in this research may help identifying patients who are most likely to benefit from specific treatments for plaque build-up in their heart arteries and those who are not likely to benefit. Therefore, this research may help allocate resources more efficiently, reduce unnecessary treatment risks for patients, and decrease the financial burden on our health care system.

描述（由申请人提供）： 对急性冠状动脉事件（心肌梗死和心脏死亡）的充分风险评估对于有效分配资源以进行预防措施很重要。多检测器计算机断层扫描（MDCT）技术的进步已将其使用从传统的放射学成像到心脏应用，从而使非侵入性冠状动脉血管造影具有高诊断准确性，以检测阻塞性冠状动脉疾病。除了仅仅是冠状动脉疾病的解剖学特征外，还对探索冠状动脉粥样硬化斑块的代谢活性也引起了极大的兴趣，因为它可以告知我们哪些斑块是或不容易触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中新生血管的存在和程度。使用MRI的研究表明，在人类颈动脉斑块中检测新血管形成的可行性，但在较小的冠状动脉斑块中没有可用于此类评估的数据。与MRI相比，MDCT具有优越的空间分辨率，因此对于详细的冠状动脉成像，似乎可以更好地定位。我们假设高度代谢活跃的动脉粥样硬化斑块将与较不活跃的斑块不同，因为在组织中的对比度增强的摄取增强了较高的血管化。为了检验这一假设，我们建议使用MDCT和组织病理学比较的动物模型中对冠状动脉进行图像。具体而言，我们将在9头患有冠状动脉粥样硬化和新血管形成的猪中执行MDCT，并使用新型组织X射线衰减分析图像。在第二步中，我们将使用微CT进行冠状动脉的体内成像。与常规MDCT相比，微型CT具有优越的空间分辨率，但不可用于临床使用。如果MDCT无法检测到冠状动脉粥样硬化斑块之间或多或少的血管形成斑块之间的实际差异，则Micro CT可能会证实我们的假设。最后，我们将比较MDCT和Micro CT检测到的血管化的存在和程度与组织病理学的结果。该提案的重要性在于可能性可能确定一种新的方法来检测冠状动脉粥样硬化斑块，这些斑块具有更代谢活跃并且可能易受伤害的冠状动脉斑块，即与较高的冠状动脉事件风险相关，使用广泛可用的工具。因此，该提案可能会导致我们识别出可能立即适用于许多患者的急性冠状动脉事件风险增加的患者的能力，从而取得了重大进步。 公共卫生相关性： 这项研究旨在开发一种表征通过计算机断层扫描（CT）观察到的心动脉中斑块生物学活性的方法。这项研究中提出的方法可能有助于识别最有可能受益于心脏动脉中牙菌斑堆积的特定疗法的患者，以及那些不太可能受益的患者。因此，这项研究可能有助于更有效地分配资源，减少患者的不必要的治疗风险，并减轻我们的医疗保健系统的财务负担。