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

本研究的目的是在动物实验和临床研究中阐明心肌内电容血管在冠状动脉循环调节中的生理和病理生理学作用。在麻醉开胸犬，在冠脉灌流压力控制下，用光纤激光多普勒测速仪测量冠脉流入(动脉流量)和冠状动脉流出(冠脉流量)。另一方面，在心脏手术中使用80道20 MHz超声多普勒测速仪测量人体冠状动脉和静脉血流。心肌内电容血管的功能特征由两个因素组成：无应力体积(UV)和通常的顺应性。紫外线的特性适合于储存血液，其容量为5ml/100g LV。当紫外线充填血液时，冠状动脉流入阻力增加，而零流压没有明显变化。冠状静脉的时相血流主要由心肌内血管内储存的血液调节。血液的流变性不仅影响冠状动脉的流入阻力，而且还影响冠状动脉的零流压。应用20 MHz 80道超声多普勒测速仪对心脏手术中冠状动脉狭窄后的血流动力学进行了分析。阐明了压力超负荷性肥厚时冠状动脉血流的时相特征。我们研制了双芯光纤激光多普勒测速仪，用于测量远离光纤的血液流动和扰动流动。

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.