Collet A, Bragard J, Dauby P C
GIGA In silico medicine, Liège University, B-4000 Liège, Belgium.
Physics and Applied Math. Dept., Universidad de Navarra, Pamplona E-31080, Spain.
Chaos. 2017 Sep;27(9):093924. doi: 10.1063/1.5000710.
This article characterizes the cardiac autonomous electrical activity induced by the mechanical deformations in the cardiac tissue through the mechano-electric feedback. A simplified and qualitative model is used to describe the system and we also account for temperature effects. The analysis emphasizes a very rich dynamics for the system, with periodic solutions, alternans, chaotic behaviors, etc. The possibility of self-sustained oscillations is analyzed in detail, particularly in terms of the values of important parameters such as the dimension of the system and the importance of the stretch-activated currents. It is also shown that high temperatures notably increase the parameter ranges for which self-sustained oscillations are observed and that several attractors can appear, depending on the location of the initial excitation of the system. Finally, the instability mechanisms by which the periodic solutions are destabilized have been studied by a Floquet analysis, which has revealed period-doubling phenomena and transient intermittencies.
本文通过机械电反馈来描述心脏组织中机械变形所诱导的心脏自主电活动。使用一个简化的定性模型来描述该系统，并且我们还考虑了温度效应。分析强调了该系统具有非常丰富的动力学特性，包括周期解、交替变化、混沌行为等。详细分析了自持振荡的可能性，特别是根据诸如系统维度和牵张激活电流的重要性等重要参数的值。还表明高温显著增加了观察到自持振荡的参数范围，并且根据系统初始激发的位置可能会出现几个吸引子。最后，通过弗洛凯分析研究了周期解失稳的不稳定性机制，该分析揭示了倍周期现象和瞬态间歇性。
