Measurement of tissue and hemodynamic wave phenomena in cardiac function

由于正常心脏功能的复杂性和难以获得足以对功能进行现实描述的高质量体内数据，从工程角度来看，心脏力学和血流的研究具有挑战性。毫不奇怪，我们的心脏如何工作的基本方面仍然没有被描述出来。在这个计划中，特别令人感兴趣的是“波”在心脏功能中的重要性，包括心肌中的机械波和血液中的压力波。波通常在血管中被观察到，例如，通常在手腕处测量脉搏，但波在心脏中的表现却不太清楚。我们提出，如果没有波的描述，心脏功能本身的基本方面就不能准确地描述，这将代表当前心脏生物力学描述的转变。高时间和高空间分辨率成像数据（来自磁共振成像）将被获取和处理，以评估心脏肌肉应变随时间和空间的模式，这是研究肌肉内波传播所必需的。对心脏血液池的类似测量将用于显示心脏的波动运动如何在血液中产生类似的波动模式，最终驱动我们身体所依赖的血液流动。这项工作的长期目标是开发研究心脏和血液运动的工具，并描述工作心脏的实际机械和流体动力学，这最终是了解许多心脏疾病的正常功能和异常功能所必需的。

The study of the cardiac mechanics and blood flow is challenging from an engineering perspective due to the complexity of normal heart function and the difficulty in acquiring high quality in-vivo data that is sufficient for realistic descriptions of function. Not surprisingly there remain fundamental aspects of how our heart works that are not described. Of particular interest in the proposed program is the importance of "waves" in heart function, both mechanical waves in the heart muscle and pressure waves that travel in the blood. Waves are commonly observed in the blood vessels, giving rise to the pulse commonly measured at ones wrist, for example, but the manifestation of waves in the heart is not well understood. We propose that fundamental aspects of heart function itself cannot be accurately described without a wave description, which would represent a shift in the current biomechanical descriptions of the heart. High temporal and high spatial resolution imaging data (from magnetic resonance imaging) will be acquired and processed to evaluate the patterns of muscle strain over time and space in the heart that are necessary to study the propagation of waves within the muscle. Similar measurements within the blood pool in the heart will be used to show how wave-like motion of the heart gives rise to comparable wave patterns in the blood which ultimately drive the blood flow that our bodies depend upon. The long term goals of this work are to develop tools to study heart and blood motion and to describe the realistic mechanical and fluid dynamics of the working heart, which ultimately are necessary to understand both normal function and abnormal function in the many diseases of the heart.