DISTRIBUTION OF MYOCARDIAL STRESS AND ITS INFLUENCE ON CORONARY BLOOD-FLOW
DISTRIBUTION OF MYOCARDIAL STRESS AND ITS INFLUENCE ON CORONARY BLOOD-FLOW
复制标题
DOI：
10.1016/0021-9290(85)90478-6
复制
发表时间：
1985-01-01
影响因子：
2.4
通讯作者：
JAN, KM
中科院分区：
文献类型：
--
作者：
JAN, KM
通过生物力学模型结合实验结果分析心肌应力。压力-容积关系遵循肌纤维的应力-应变关系。从肌纤维的取向和肌节长度的分布出发，将心肌的应力分量（包括纤维应力、纵向应力、周向应力和径向应力）表示为壁厚分数的函数。冠状动脉血流受心肌径向应力的影响。使用血管瀑布理论，可以将理论上定义的应力分布与实验获得的应力分布相关联。心肌中径向应力的升高导致血管通畅性降低。在收缩期和舒张期，心外膜处的血管通畅性保持恒定。然而，在内径，血管通畅性经历了径向应力的收缩期和舒张期影响的节律性变化。生理学意义是在收缩期，内皮细胞遭受低血流量，这种短暂的缺血状态需要舒张灌注的代偿性补充。这种现象在心外膜处变得不那么明显。
The myocardial stress was analyzed by biomechanical modeling in correlation with experimental findings. The pressure-volume relationship follows the stress-strain relationship of muscle fibers. From the knowledged of fiber orientation and the distribution of sarcomere length, the myocardial stress components including fiber, longitudinal, circumferential and radial stresses were expressed as a function of fraction of wall thickness. The coronary blood flow is influenced by the myocardial radial stress. With the use of vascular waterfall theory, it is possible to correlate the theoretically defined stress distribution with experimentally obtained stress distribution. An elevation of radial stress in myocardium causes a reduction of vessel patency. During both systole and diastole, vessel patency remains constant at epicardium. At endocardium, however, vessel patency undergoes rhythmic changes following the systolic and diastolic influences of the radial stress. The physiological implication is that during systole, the endocardium suffers low blood flow and this transient ischemic state requires compensatory replenishment from diastolic perfusion. Such phenomena become less apparent toward the epicardium.