SPIRAL TIP MOVEMENT: THE ROLE OF THE ACTION POTENTIAL WAVELENGTH IN POLYMORPHIC CARDIAC ARRHYTHMIAS
SPIRAL TIP MOVEMENT: THE ROLE OF THE ACTION POTENTIAL WAVELENGTH IN POLYMORPHIC CARDIAC ARRHYTHMIAS
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螺旋尖端运动：动作电位波长在多形性心律失常中的作用
DOI：
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发表时间：
1996
期刊：
影响因子：
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通讯作者：
J. Starobin
中科院分区：
文献类型：
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作者：
C. Starmer;J. Starobin
心源性猝死之前通常伴有折返性（螺旋波）快速性心律失常，与动作电位波长延长相关。钾通道阻滞、低钾血症和膜离子通道的遗传改变（例如长QT综合征）都可导致动作电位波长延长。在心肌细胞的实验中，我们发现钾通道阻断也可以促进膜电位的瞬时振荡，然后可以引发瞬时或持续的节律紊乱。使用一个简单的FitzHugh-Nagumo模型的可兴奋细胞，我们观察到，延长所需的时间为兴奋的细胞恢复到休息状态（相当于钾通道阻断或低钾血症）放大的螺旋尖端运动（蜿蜒）的区域。当弯曲区域相对于整个心肌表面较大时，QRS振幅和构型从一个折返周期到下一个折返周期变化，并类似于在心脏动脉中看到的模式。
Sudden cardiac death is often preceded by re-entrant (spiral wave) tachyarrhythmias associated with a prolongation of the action potential wavelength. Potassium channel blockade, hypokalemia and genetic alterations in membrane ion channels (e.g. long QT syndrome) can all lead to extension of the action potential wavelength. In experiments with cardiac cells, we have found that potassium channel blockade can also promote transient oscillation of the membrane potential which can then initiate transient or sustained rhythm disturbances. Using a simple FitzHugh–Nagumo model of an excitable cell, we observed that extending the time required for an excited cell to return to the rest state (equivalent to potassium channel blockade or hypokalemia) amplified the region of spiral tip movement (meandering). When the region of meandering was large relative to the total myocardial surface, the QRS amplitude and configuration varied from one re-entrant cycle to the next and resembled the patterns seen in the cardiac ar...