Experimental and clinical analysis of functional characteristics of intramyocardial microvessls and its disorders

本研究旨在通过动物实验和临床研究阐明心内电容血管在调节冠状动脉循环中的生理和病理生理作用。在冠脉灌注压控制下，采用光纤激光多普勒测速仪测量麻醉开胸犬冠脉流入（动脉流量）和冠脉流出（冠脉静脉流量）。另一方面，在心脏手术期间，用80通道20 MHz超声多普勒测速仪测量人冠状动脉和静脉血流。心内电容血管的功能特征由无压力容量（UV）和正常顺应性两个因素组成。UV的特性适合于储血，其容量为5ml/100g LV。当UV充满血液时，冠状动脉流入阻力增加，但零流压无明显变化。冠状静脉的相位血流主要受心肌血管内储血量的调节。血液的流变特性不仅影响冠状动脉的流入阻力，而且影响冠状动脉的零流压。采用20MHz 80通道超声多普勒测速仪分析心脏手术过程中人狭窄后冠状动脉血流动力学。同时也阐明了压力过载时冠状动脉肥厚的期相特征。研制了双芯光纤激光多普勒测速仪，该测速仪可用于测量光纤外血流和扰动血流。

The purpose of this study was to clarify the physiological and pathophysiological role of intramyocardial capacitance vessels in the regulation of coronary circulation in animal experiment and clinical research. In anesthetized open-chest dogs coronary inflow(artery flow) coronary outflow(coronary vein flow) were measured by an optical fiber laser doppler velocimeter under control of coronary perfusion pressure. On the other hand, human coronary artery and vein flows were measured by an 80 channel 20 MHz ultrasound doppler velocimeter during cardiac surgery.Functional characteristics of intramyocardial capacitance vessels were composed of two factors: unstressed volumes(UV) and usual compliance. The characteristics of UV is fitted to store blood and its capacity is found to be 5ml/100g of LV. The coronary inflow resistance increased without significant changes of zero-flow pressure, when UV was filled with blood. The phasic coronary vein flow was mainly regulated by the blood stored within intramyocardial vessels. The rheological property of blood had effects on not only inflow resistance but also zero-flow pressure of the coronary artery. The fluid dynamics of the human poststenotic coronary artery folw was analyzed by 20MHz 80 Channel ultrasound Doppler velocimeter during cardiac surgery. the phasic characteristics of coronary artery folw in pressure overload human hypertrophy was also clarified. We developped dual-core optical fiber laser doppler velocimeter, which is useful for the measurement of blood flow away from the fiber and disturbed flow.