异位起搏引发异常心律的计算机数值实验

Numerical Experiment on Abnormal Heartbeat Rhythms Induced by Ectopic Pacemakers

目的 :对位于心室的异位起搏点 (E)在本位起搏点 (S)强弱不同的两种重置作用进行计算机数值实验 ,研究心脏在S与E共同驱动下的节律运动。方法 :应用Ikeda相位重置模型 ,分别建立一维映象模型。结果 :参数平面上大部分的区域锁定周期性的运动模式 ,在某些参数下 ,存在着正常与异常心搏模式共存的情形 ,观察到临床上出现的二联律、三联律等异常心搏节律。结论 :较健康的心脏也可能有异常节律的心搏 。

Objective: Two heartbeat models which corresponded to two coupling styles of the sinus (S) and ectopic (E) pacemakers were used to study heartbeat. Methods: Numerical experiments were based on modified Ikeda phase resetting model. Results: Most of the heartbeat modes were periodic, which exhibited 'Arnold's tongue' structure in parameter plane of perturbing frequency and strength. Conclusion: The abnormal heartbeat rhythms of bigeminy and trigeminy in clinic have been observed when coupling strength is weaker in odd resetting or refractory time is longer in even resetting.