Use of Real Time MRI for Evaluation of Regional Myocardial Function

使用实时 MRI 评估局部心肌功能

• 批准号: 8891198
• 负责人: Francisco J Contijoch
• 金额: $ 0.34万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-01 至 2015-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8891198
• 关键词: Acceleration; Acute myocardial infarction; Address; Algorithms; Animals; Biochemistry; Cessation of life; Collagen; Data; Data Set; Development; Dobutamine; Error Sources; Evaluation; Family suidae; Frequencies; Goals; Gold; Health; Heart failure; Histology; Hospitals; Image; Imaging Techniques; Infarction; Infusion procedures; Magnetic Resonance Imaging; Measurement; Measures; Mechanics; Methods; Modeling; Modification; Morphologic artifacts; Motion; Myocardial; Nature; Noise; Patients; Performance; Physiologic intraventricular pressure; Physiological; Pilot Projects; Prevention therapy; Process; Property; Resolution; Risk; Sampling; Signal Transduction; Stem cells; Sturnus vulgaris; Techniques; Testing; Thick; Time; Validation; Ventricular; Ventricular Remodeling; Visit; Work; base; density; design; detector; heart motion; image reconstruction; improved; in vivo; men; mortality; novel; pressure; prevent; reconstruction; regional difference; success; temporal measurement

DESCRIPTION (provided by applicant): Heart failure is the cause of 270,000 deaths in the U.S. and 3.4 million annual hospital visits. The risk-adjusted 1-year mortality of heart failure ha remained essentially unchanged between 1999 (31.7%) and 2008 (29.6%), despite a significant decrease in mortality associated with acute myocardial infarction (10.7% per year for men). Recent attempts to prevent post-infarction heart failure through novel pharmacologic, stem cell, and mechanical therapies have shown promise in animal studies but subsequent studies in patients showed very limited success. This can be partly attributed to the lack of high spatial resolution methods to evaluate the consequences of infarction and subsequent therapy on regional contractile function and myocardial health. Current gold-standard approaches to determine contractile function include pressure-volume loops and strain measurement via MRI. Although MRI can image LV function and strain with high spatial resolution, it is a multi- shot, multiple heartbeat acquisition that is too slow to measure beat-to-beat changes in myocardial work. The goal of this project is to develop real-time MRI methods to measure regional myocardial work density and Frank-Starling relations during infarct development and validate these results with conventional MRI and biochemistry in a porcine model. To achieve this goal, (1) the rt-MRI approach will be improved and optimized. Compressed sensing will further improve the current sub-Nyquist image reconstruction algorithm we have implemented. In addition, modification of the k-space sampling trajectory will improve artifact incoherence and algorithm performance. Then, (2) validation of regional estimates of myocardial function will be performed. The proposed method tracks myocardial wall thickening and regional work density and Frank-Starling relations. SPAMM-tagged images and conventional CINE imaging of ventricular motion will be used to generate comparable values. Finally, (3) an initial serial infart swine study will be used to correlate observed rt-MRI based changes in function to histological testing. This will determine the spatial resolution and temporal accuracy of the proposed method. The proposal develops a method to allow for in-vivo and longitudinal evaluation of post-infarction ventricular remodeling. Such a method is necessary for advanced design and evaluation of novel therapies for prevention of infarct-induced heart failure.

描述（由申请人提供）：心力衰竭是美国270,000人死亡和340万例医院就诊的原因。在1999年（31.7％）和2008年（29.6％）之间，经过风险调整的1年心力衰竭死亡率仍然保持不变，尽管与急性心肌梗塞相关的死亡率显着降低（男性每年10.7％）。最近通过新型药物，干细胞和机械疗法预防障碍后心力衰竭的尝试在动物研究中表现出了希望，但随后对患者的研究表现出非常有限的成功。这可以部分归因于缺乏高空间分辨率方法来评估梗塞后果以及随后的治疗对区域收缩功能和心肌健康的后果。确定收缩功能的当前金标准方法包括通过MRI进行压力卷环和应变测量。尽管MRI可以以高空间分辨率为LV功能和应变，但它是一种多镜头，多次心跳的采集，它太慢，无法测量心肌作品的Beat-Beat变化。该项目的目的是开发实时MRI方法，以在梗死过程中测量梗死过程中区域心肌的密度和坦率的停滞关系，并在猪模型中使用常规MRI和生物化学验证这些结果。为了实现这一目标，（1）RT-MRI方法将得到改进和优化。压缩传感将进一步改善我们已经实施的当前的子nyquist图像重建算法。此外，修改K空间采样轨迹将改善伪影不连贯和算法性能。然后，（2）将对心肌功能的区域估计进行验证。所提出的方法跟踪心肌壁增厚和区域工作密度和坦率的宣传关系。垃圾邮件标记的图像和心室运动的常规Cine成像将用于产生可比的值。最后，（3）最初的串行猪研究将用于将基于RT-MRI的功能变化与组织学检测相关联。这将确定所提出方法的空间分辨率和时间准确性。该提案开发了一种允许对室内室内重塑后体内和纵向评估的方法。这种方法对于预防梗塞引起的心力衰竭的新型疗法的高级设计和评估是必需的。