Virtual cell and tissue dynamics of ectopic activation of the ventricles
Virtual cell and tissue dynamics of ectopic activation of the ventricles
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DOI：
10.1063/1.2404634
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发表时间：
2007-03-01
期刊：
影响因子：
2.9
通讯作者：
Holden, Arun V.
中科院分区：
文献类型：
--
作者：
Benson, Alan P.;Halley, Graeme;Holden, Arun V.
正常情况下，心脏的心室细胞和组织是可兴奋的，并被在心脏特殊起搏区域启动的兴奋波的传播所激活。然而，孤立的或重复的活动可以在脑室的异常(异位)位置启动。要触发内源性异位搏动，必须有一个紧凑的焦点细胞具有改变的膜兴奋参数和动力学，这些细胞通过由传播活动触发的后去极化来启动活动，或者已经分叉成自律性。这种异位病灶需要足够大，并充分耦合，以驱动周围组织。我们研究了由后去极化和特定膜电导系统的上调/下调触发的人心室细胞计算模型中异位兴奋的启动，以及异位活动在同质或异质和各向同性、各向异性或正交性组织中的传播和演化。(C)2007年美国物理研究所。
Cardiac ventricular cells and tissues are normally excitable, and are activated by propagating waves of excitation that are initiated in the specialized pacemaking region of the heart. However, isolated or repetitive activity can be initiated at abnormal (ectopic) sites in the ventricles. To trigger an endogenous ectopic beat, there must be a compact focus of cells with changed membrane excitation parameters and kinetics, which initiate activity by after-depolarizations triggered by propagating activity, or that have bifurcated into autorhythmicity. This ectopic focus needs to be large enough, and adequately coupled, to drive the surrounding tissue. We investigate the initiation of ectopic excitation in computational models of human ventricular cells triggered by after-depolarizations and by up/down regulation of specific membrane conductance systems, and the propagation and evolution of ectopic activity in homogeneous or heterogeneous and isotropic, anisotropic, or orthotropic tissues. (c) 2007 American Institute of Physics.