MRI of cardiac function and myocardial tissue properties

心脏功能和心肌组织特性的 MRI

• 批准号: 6967052
• 负责人: HAN WEN
• 金额: --
• 依托单位: NATIONAL HEART, LUNG, AND BLOOD INSTITUTE
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6967052
• 关键词: bioimaging /biomedical imaging; heart circulation; heart contraction; heart function; heart imaging /visualization /scanning; heart motion; human subject; hypertension; magnetic resonance imaging; myocardial ischemia /hypoxia; myocardium; patient oriented research; perfusion; technology /technique development

The compliance of the cardiac muscle in diastole is important to normal filling of the heart prior to ejection. In many heart failure patients with normal systolic function, the "stiff heart syndrome" is likely caused by stiffened heart muscle. In the last year we have confirmed the accuracy of a non-invasive, MRI based measurement of heart muscle compliance, demonstrated its feasibility in humans, and showed the stiffening of the muscle following ischemic injury. We now have a protocol to look at patients with hypertension to see if muscle complaince is specifically responsible for their conditions. We also observed a unique feature of blood flow in the heart, the out-of-phase arterial and venous flow in small branches of the coronary tree due to of the squeezing effect of heart contraction. We measuremented tissue volume changes due to this effect, which give an independent estimate of perfusion of the heart wall, and points to a mechanism of very timely coupling of mechanical work and oxygen delivery in the heart.

舒张期心肌的顺应性对于心脏射血前的正常充盈非常重要。在许多收缩功能正常的心力衰竭患者中，“心脏僵硬综合征”很可能是由心肌僵硬引起的。在过去的一年里，我们证实了一种基于MRI的非侵入性心肌顺应性测量的准确性，证明了其在人类中的可行性，并显示了缺血损伤后肌肉的僵硬。我们现在有一个方案来观察高血压患者，看看肌肉主诉是否对他们的病情有明确的责任。 我们还观察到心脏血流的一个独特特征，由于心脏收缩的挤压效应，冠状动脉树小分支中的动静脉异相流动。我们测量了由这种效应引起的组织体积变化，这给出了心壁灌注量的独立估计，并指出了心脏中机械功和氧气输送非常及时地耦合的机制。