Veteĭkis R
Institute for Biomedical Research, Kaunas, Lithuania.
Biofizika. 1997 Nov-Dec;42(6):1286-91.
The work was centered on theoretical investigation of the spread of electrotonic potential in the cardiac tissue during the delivery of long-term rectangular pre-threshold current impulses to the tissue. A mathematical model of two-dimensional anisotropic medium, with a circumference-shaped current source, has been developed. In accordance with the superposition principle well-known in electrostatics, the source of current was approximated by point sources placed on the perimeter of the current source in two ways: 1) by regular division of the perimeter of the current source in metric coordinate system, 2) by regular division of the perimeter of current source in the normalized coordinate system. Computerized programs have been developed for the computation of the distribution of electrotonic potential in the two-dimensional anisotropic medium. Families of curves were established evaluating the dependence of half-time (time during which electrotonic potential reaches half the stationary amplitude) on the size of the current source, anisotropy, the distance between the center of the current source and the point of registration (calculation) of electrotonic potential. Near the current source the dependence of half-time on the distance declines from linear.
这项工作主要围绕在向心脏组织施加长期矩形阈前电流脉冲期间,对心脏组织中电紧张电位传播的理论研究展开。已开发出一个具有圆周形电流源的二维各向异性介质数学模型。根据静电学中熟知的叠加原理,电流源通过以下两种方式由置于电流源周边的点源近似表示:1)在度量坐标系中对电流源周边进行规则划分;2)在归一化坐标系中对电流源周边进行规则划分。已开发出用于计算二维各向异性介质中电紧张电位分布的计算机程序。建立了一系列曲线,用于评估半衰期(电紧张电位达到稳定振幅一半所需的时间)与电流源大小、各向异性、电流源中心与电紧张电位记录(计算)点之间距离的关系。在电流源附近,半衰期与距离的关系从线性下降。