Anatomical and Functional Assessment of Coronary Artery Disease Using Whole-Heart Dynamic Computed Tomography

项目总结/摘要 冠状动脉疾病（CAD）是全球发病率和死亡率的主要原因。幸运的是， 当使用计算的风险分层时， 断层扫描血管造影术（CTA）和适当的药物治疗或血运重建治疗。 不幸的是，CTA的局限性在于病变严重程度仅基于病变形态;因此， 侧支化、钙化和伪影经常混淆诊断结果。CAD视觉分级 还具有高的观察者内和观察者间变异性，并且通常与心肌缺血的相关性差， 特别是对于中等严重程度的局灶性疾病（30-70%管腔狭窄）、弥漫性疾病，以及 微血管疾病因此，单独使用CTA无法完全表征CAD的真实严重程度， 功能评估技术，如动态计算机断层扫描灌注（CTP）， 需要与CTA联合使用，以更客观地指示CAD的意义。不幸的是， 这种动态CTP技术系统地低估了灌注， 每次CAD检查的辐射剂量，阻碍了其广泛的临床应用。 鉴于CTA和动态CTP的局限性，该提案旨在验证准确、低剂量、 基于首过分析的CTA与动态CTP融合技术 CAD的解剖和功能评估。核心假设是同时习得 使用全心脏CT扫描仪、两次容积扫描和一次 造影剂注射将使得能够进行精确的、低剂量的、血管特异性的心肌灌注测量。 具体来说，我的目标是确定是否可以准确地测量血管特异性心肌灌注， 15头猪通过回顾性实施FPA CTAP技术。我还想确定 在15只以上的猪中，通过低剂量 FPA CTAP技术的预期实施。 通过验证这种CAD评估的组合方法，本研究可能最终减少 与CTA和动态CTP相关的造影剂和辐射剂量，同时改善测量 准确性，使CAD的解剖和功能评估更容易获得，更有效， 病人需要。

PROJECT SUMMARY/ABSTRACT Coronary artery disease (CAD) is the leading cause of morbidity and mortality worldwide. Fortunately, morbidity and mortality are significantly reduced when patients are risk stratified using computed tomography angiography (CTA) and treated appropriately with medical therapy or revascularization. Unfortunately, CTA is limited in that lesion severity is based solely on lesion morphology; hence, collateralization, calcification, and artifacts often confound diagnostic results. Visual grading of CAD also has high intra- and inter-observer variability, and often correlates poorly with myocardial ischemia, especially for intermediate severity focal disease (30-70% luminal narrowing), diffuse disease, and microvascular disease. Hence, CTA alone cannot fully characterize the true severity of CAD, and functional assessment techniques, such as dynamic computed tomography perfusion (CTP), are necessary, in conjunction with CTA, for more objective indication of CAD significance. Unfortunately, such dynamic CTP techniques systematically underestimate perfusion and deliver unacceptably high radiation doses per CAD exam, hampering their widespread clinical utility. Given the limitations of CTA and dynamic CTP, this proposal aims to validate an accurate, low-dose, CTA and dynamic CTP fusion technique based on first-pass analysis (FPA CTAP) for combined anatomical and functional assessment of CAD. The central hypothesis is that simultaneous acquisition of CTA and dynamic CTP data using a whole-heart CT scanner, two volume scans, and a single contrast injection will enable accurate, low-dose, vessel-specific myocardial perfusion measurement. Specifically, I aim to determine if vessel-specific myocardial perfusion can be accurately measured in 15 swine through retrospective implementation of the FPA CTAP technique. I also aim to determine if vessel-specific myocardial perfusion can be accurately measured in 15 more swine through low-dose prospective implementation of the FPA CTAP technique. By validating such a combined approach to CAD assessment, this research may ultimately reduce the contrast and radiation dose associated with CTA and dynamic CTP, while improving measurement accuracy, making anatomical and functional assessment of CAD more accessible and impactful to patients in need.