Rate dependence of early afterdepolarizations in the His-Purkinje system: A simulation study

Zihui Geng; Lian Jin; Yanqi Huang; Xiaomei Wu

doi:10.1016/j.cmpb.2022.106665

Rate dependence of early afterdepolarizations in the His-Purkinje system: A simulation study

Comput Methods Programs Biomed. 2022 Apr:217:106665. doi: 10.1016/j.cmpb.2022.106665. Epub 2022 Jan 29.

Authors

Zihui Geng¹, Lian Jin², Yanqi Huang³, Xiaomei Wu⁴

Affiliations

¹ Academy for Engineering and Technology, Fudan University, 220 Handan Road, Shanghai, 200433, China. Electronic address: zhgeng19@fudan.edu.cn.
² Center for Biomedical Engineering, School of information Science and Technology, Fudan University, 220 Handan Road, Shanghai, 200433, China. Electronic address: ljin16@fudan.edu.cn.
³ Center for Biomedical Engineering, School of information Science and Technology, Fudan University, 220 Handan Road, Shanghai, 200433, China. Electronic address: yanqihuang17@fudan.edu.cn.
⁴ Center for Biomedical Engineering, School of information Science and Technology, Fudan University, Shanghai Engineering Research Center of Assistive Devices, Yiwu Research Institute of Fudan University, 322000, Chengbei Road, Yiwu City, 322000 Zhejiang, China; Key Laboratory of Medical Imaging Computing and Computer Assisted Intervention (MICCAI) of Shanghai, 220 Handan Road, Shanghai, 200433, China. Electronic address: xiaomeiwu@fudan.edu.cn.

PMID: 35172249
DOI: 10.1016/j.cmpb.2022.106665

Abstract

Background and objective: Early afterdepolarizations (EADs) are associated with a variety of arrhythmias and have the property of rate dependence. EADs can occur in Purkinje cells while the effect of rate dependence of EADs in the His-Purkinje system has not been fully investigated. In order to reveal the rate dependence of EADs in the His-Purkinje system and its effect on ventricular electrical activities, the simulation research was carried out in this manuscript.

Methods: This manuscript first studied the relationship between the occurrence of EADs and stimulation cycle length on the DiFranNoble cell model. Then, the relationship between the rate dependence of EADs and the conduction block of the His-Purkinje system at slow heart rates was studied on the rabbit whole ventricular model including the His-Purkinje system, and its mechanism was analyzed from multiple angles.

Results: ① The rate dependence of EADs is related to the inconsistency of EADs occurrence in the His-Purkinje system. When the stimulation cycle length is long or short enough, EADs either occur or not occur stably in the His-Purkinje system, while in a certain stimulation cycle length window, the chaotic state of EADs will be observed. ② The key subcellular factors x-gate is an important mechanism involved to the rate dependence of EADs in the His-Purkinje system. ③ The discrete distribution of x-gate values and the "source-sink" mechanism lead to the inconsistency of EADs in the His-Purkinje system. The prolonged action potential duration caused by EADs can lead to conduction block at slow heart rates.

Conclusion: The rate dependence of EADs in Purkinje system can lead to disordered ventricular electrical activity.

Keywords: Action potential; Cardiac electrophysiology simulation; Early afterdepolarizations; His-Purkinje system; Rate dependence.

MeSH terms

Action Potentials
Animals
Arrhythmias, Cardiac*
Computer Simulation
Rabbits