Vortex filament dynamics in computational models of ventricular fibrillation in the heart
Vortex filament dynamics in computational models of ventricular fibrillation in the heart
复制标题
DOI：
10.1063/1.3043805
复制
发表时间：
2008-12-01
期刊：
影响因子：
2.9
通讯作者：
Clayton, Richard H.
中科院分区：
文献类型：
--
作者：
Clayton, Richard H.
在三维心脏组织中，维持心室颤动的折返波围绕相位奇点线或涡丝旋转。本研究的目的是调查这些涡丝的行为是如何影响膜动力学，初始条件，和组织的几何形状在计算模型的兴奋组织。使用心脏组织的单域模型，动力学由三变量简化离子模型（3V-SIM）描述。使用了两种版本的3V-SIM，一种具有陡峭的动作电位持续时间恢复，另一种具有降低的兴奋性。然后在三种组织几何形状中模拟折返性纤颤：立方体、平板和兔心室的解剖学详细模型。使用基于相位的方法识别细丝，并且在每个模拟中跟踪细丝的数量、尺寸、起源和取向。这项研究的主要发现是，动力学，初始条件，几何形状，和各向异性都影响的数量，增殖和方向的涡丝在折返纤颤。本研究的一个重要发现是，代表心室壁部分的简化平板几何形状中的涡丝行为不一定能预测家兔心室解剖学详细模型中的行为。
In three-dimensional cardiac tissue, the re-entrant waves that sustain ventricular fibrillation rotate around a line of phase singularity or vortex filament. The aim of this study was to investigate how the behavior of these vortex filaments is influenced by membrane kinetics, initial conditions, and tissue geometry in computational models of excitable tissue. A monodomain model of cardiac tissue was used, with kinetics described by a three-variable simplified ionic model (3V-SIM). Two versions of 3V-SIM were used, one with steep action potential duration restitution, and one with reduced excitability. Re-entrant fibrillation was then simulated in three tissue geometries: a cube, a slab, and an anatomically detailed model of rabbit ventricles. Filaments were identified using a phase-based method, and the number, size, origin, and orientation of filaments was tracked throughout each simulation. The main finding of this study is that kinetics, initial conditions, geometry, and anisotropy all affected the number, proliferation, and orientation of vortex filaments in re-entrant fibrillation. An important finding of this study was that the behavior of vortex filaments in simplified slab geometry representing part of the ventricular wall did not necessarily predict behavior in an anatomically detailed model of the rabbit ventricles.