High-Resolution Whole Heart Quantitative CMR Perfusion Imaging in Ischemic Heart Disease

7.项目摘要 超过800万美国人因阻塞性冠状动脉疾病（CAD）或 微血管疾病（MVD），两者均与不良心血管疾病风险增加相关。 事件，准确无创评估阻塞性CAD的存在和功能意义， MVD的评估具有重要的临床意义。虽然CAD和MVD的特征在于 冠状动脉血流储备（CFR）异常，仅此参数不足以区分这两者 有不同的管理策略。高分辨率全心定量腺苷 负荷心脏磁共振（CMR）有可能提供一种新的工具，以区分 这些实体基于其量化心内膜和心外膜灌注之间差异的能力。 然而，3D定量腺苷应激CMR仍然受到许多重要限制，包括 有限的空间覆盖范围、低平面内空间分辨率、长时间采集窗口以及对 心脏和呼吸运动。我们一直在开发高效的高分辨率2D螺旋CMR灌注 脉冲序列，以克服这些限制，同时提供全心脏覆盖。 该项目的广泛长期目标是开发强大的高分辨率定量CMR灌注 全心脏覆盖技术，以了解动物灌注异常的发展 微血管疾病和阻塞性CAD模型，并利用这些CMR技术来改善 CAD和MVD患者的无创诊断和风险分层。改进诊断技术 用于评估CAD和MVD中的心肌灌注可以显著减少对侵入性冠状动脉造影的需求。 正在评估心绞痛患者的血管造影。 本课题的具体目标是：（1）开发一种高效的高分辨率二维螺旋灌注成像系统 用于心肌灌注和内皮素的稳健、运动不敏感和精确测量的技术 与心外膜（endo：ep）灌注比。(2)检验CMR准确测量endo：epi的假设 与猪模型中的MVD相比，在阻塞性CAD中检测到更低的endo：epi比率。 (3)开发一种算法，使用CMR导出的MPR和Endo：Epi灌注比区分CAD和 心绞痛和已知或疑似CAD患者的MVD。 该项目的成功完成将导致一个高效，强大，以及验证技术的高， 能够准确检测Endo：EPI灌注的心肌灌注的分辨率全心脏量化 梯度，量化MPR和心肌缺血负荷，并区分梗阻性CAD与MVD。的 非常短的时间足迹和运动不敏感的重建将使鲁棒的灌注量化， 心率增加和无法屏气的患者，扩展了CMR的适用性。

7. Project Summary As greater than 8 million Americans suffer from angina due to obstructive coronary artery disease (CAD) or microvascular disease (MVD), which are both associated with an increased risk for adverse cardiovascular events, accurate non-invasive assessment of the presence and functional significance of obstructive CAD and evaluation of MVD is of substantial clinical importance. While both CAD and MVD are characterized by abnormal coronary flow reserve (CFR), this parameter alone is insufficient to distinguish between these two conditions which have different management strategies. High-resolution whole-heart quantitative adenosine stress cardiac magnetic resonance (CMR) has the potential to provide a new tool to differentiate between these entities based on its ability to quantify differences between endocardial and epicardial perfusion. However, 3D quantitative adenosine stress CMR still suffers from a number of important limitations including limited spatial coverage, low in-plane spatial resolution, long temporal acquisition windows, and sensitivity to cardiac and respiratory motion. We have been developing efficient high-resolution 2D spiral CMR perfusion pulse sequences to overcome these limitations while providing whole-heart coverage. The broad long-term objective of this project is to develop robust high-resolution quantitative CMR perfusion techniques with whole-heart coverage to understand the development of perfusion abnormalities in animal models of microvascular disease and obstructive CAD, and to utilize these CMR techniques to improve the non-invasive diagnosis and risk stratification of patients with CAD and MVD. Improved diagnostic techniques for assessing myocardial perfusion in CAD and MVD could significantly reduce the need for invasive coronary angiography among patients being evaluated for angina. The specific aims for this project are: (1) To develop an efficient high-resolution 2D spiral-based perfusion technique for robust, motion-insensitive and accurate measurements of myocardial perfusion and endocardial to epicardial (endo:ep) perfusion ratio. (2) To test the hypothesis that CMR accurately measures endo:epi perfusion ratios and detects a lower endo:epi ratio in obstructive CAD as compared to MVD in a porcine model. (3) To develop an algorithm using CMR derived MPR and endo:epi perfusion ratios to differentiate CAD from MVD in patients presenting with angina and known or suspected CAD. Successful completion of this project will result in an efficient, robust, and well-validated technique for high- resolution whole-heart quantification of myocardial perfusion able to accurately detect endo:epi perfusion gradients, quantify MPR and myocardial ischemic burden, and differentiate obstructive CAD from MVD. The very short temporal footprint and motion-insensitive reconstruction will enable robust perfusion quantification in patients with increased heart rates and inability to perform breath-holding extending the applicability of CMR.