Reappraisal of Luo-Rudy dynamic cell model

The cardiac myocyte is unique in that it is responsible for the coupling of electrical impulse to mechanical function, a process with so-called "excitation-contraction coupling". There are several ions, ion channels, and regulatory pathways participating in the generation of action potential (AP), and it is a complex process. In the cardiac myocyte, dynamic change of ionic concentrations, membrane voltage following time sequence and various regulatory pathways determine the ionic channel kinetics, which can be expressed as mathematical formalisms. The properties make it feasible to use the computational approach to analyze and elucidate the underlying mechanisms of the whole cardiac cell. Over the past decades, there have been several attempts to construct the cardiac cell models based on the approach. Among them, the Luo-Rudy dynamic (LRd) model has been one of the most famous models since it was first published by Luo and Rudy in 1991. In this paper, the theory of LRd cell model and its ability for investigating several cellular arrhythmogenic pathologies in cardiac cells will be reviewed. In conclusion, the LRd cell model based on mathematical approach is a powerful method which can help recognize and investigate the interactions between individual components of the cell and study their unique role underlying the whole-cell behavior.