Arrhythmogenic Transient Dynamics in Cardiac Myocytes
Arrhythmogenic Transient Dynamics in Cardiac Myocytes
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DOI：
10.1016/j.bpj.2013.12.050
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发表时间：
2014-03-18
影响因子：
3.4
通讯作者：
Sato, Daisuke
中科院分区：
文献类型：
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作者：
Xie, Yuanfang;Izu, Leighton T.;Sato, Daisuke
心脏动作电位交替和早期后除极（埃兹）与心律失常有关。健康状况下的周期性动作电位（周期1）分叉为其他状态，例如周期2或当交替或埃兹在病理状况下发生时的混乱。交替和埃兹的机制在稳态条件下已被广泛研究，但致命的心律失常往往发生在稳态之间的过渡。为什么心律失常倾向于在过渡期发展尚不清楚。我们使用低维数学模型来分析瞬时交替和埃兹的动力学机制。我们表明，根据从一个状态到另一个的路线，动作电位交替和埃兹可能会发生在两个周期性稳态之间的过渡。所采取的途径取决于外部扰动或内在信号传导的时间过程，例如β-肾上腺素能刺激，其以不同动力学调节心脏钙和钾电流。
Cardiac action potential alternans and early afterdepolarizations, (EADs) are linked to cardiac arrhythmias. Periodic action potentials (period 1) in healthy conditions bifurcate to other states such as period 2 or chaos when alternans or EADs occur in pathological conditions. The mechanisms of alternans and EADs have been extensively studied under steady-state conditions, but lethal arrhythmias often occur during the transition between steady states. Why arrhythmias tend to develop during the transition is unclear. We used low-dimensional mathematical models to analyze dynamical mechanisms of transient alternans and EADs. We show that depending on the route from one state to another, action potential alternans and EADs may occur during the transition between two periodic steady states. The route taken depends on the time course of external perturbations or intrinsic signaling, such as beta-adrenergic stimulation, which regulate cardiac calcium and potassium currents with differential kinetics.