Effects of deformation on transmural dispersion of repolarization using in silico models of human left ventricular wedge
Effects of deformation on transmural dispersion of repolarization using in silico models of human left ventricular wedge
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DOI：
10.1002/cnm.2570
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发表时间：
2013-12-01
影响因子：
2.1
通讯作者：
Weber dos Santos, R.
中科院分区：
文献类型：
--
作者：
de Oliveira, B. L.;Rocha, B. M.;Weber dos Santos, R.
机械变形通过多个反馈回路影响心脏的电活动。本工作的目的是研究变形对跨壁复极离散度和表面电图的影响。为了实现这一目的，我们开发了一个强耦合的机电细胞模型耦合的人左心室电生理模型和主动收缩模型重新参数化的人类细胞。然后，该模型嵌入到组织模拟的基础上bidomain方程和非线性固体力学。耦合模型用于评估机械变形对复极和电描记图重要特征的影响。我们的研究结果表明，增加的T-波振幅的表面电描记图的模拟，占心脏变形的影响。这种T波振幅的增加可以通过相邻肌细胞之间耦合的变化来解释，也称为电紧张效应。复极过程中心室壁增厚有助于细胞在跨壁方向上的解耦，增强动作电位的异质性，并增加跨壁复极离散度和表面电图的T波振幅。模拟表明，相当大比例的T波振幅（15%）可能与心脏变形有关。版权所有（c）2013约翰威利父子有限公司
Mechanical deformation affects the electrical activity of the heart through multiple feedback loops. The purpose of this work is to study the effect of deformation on transmural dispersion of repolarization and on surface electrograms using an in silico human ventricular wedge. To achieve this purpose, we developed a strongly coupled electromechanical cell model by coupling a human left ventricle electrophysiology model and an active contraction model reparameterized for human cells. This model was then embedded in tissue simulations on the basis of bidomain equations and nonlinear solid mechanics. The coupled model was used to evaluate effects of mechanical deformation on important features of repolarization and electrograms. Our results indicate an increase in the T-wave amplitude of the surface electrograms in simulations that account for the effects of cardiac deformation. This increased T-wave amplitude can be explained by changes to the coupling between neighboring myocytes, also known as electrotonic effect. The thickening of the ventricular wall during repolarization contributes to the decoupling of cells in the transmural direction, enhancing action potential heterogeneity and increasing both transmural repolarization dispersion and T-wave amplitude of surface electrograms. The simulations suggest that a considerable percentage of the T-wave amplitude (15%) may be related to cardiac deformation. Copyright (c) 2013 John Wiley & Sons, Ltd.