Real-time simulations for resetting and annihilation of reentrant activity using hardware-implemented cardiac excitation modeling

In this paper, real-time simulations of reentrant excitation conduction of cardiac cells are realized by coupling 80 active circuits of the hardware-implemented cardiac excitation cell models in a one-dimensional loop. The hardware-implemented cardiac excitation model is designed by using analog circuits and a dsPIC microcontroller that could reproduce time-dependent and time-independent nonlinear current-voltage characteristics of six-type of ionic currents in Luo Rudy phase 1 (LR1) model. LR1 is a numerical model described with nonlinear ordinary differential equation (ODE) functions for generating the action potential (AP) wave in a mammalian cardiac ventricle. In the simulations of AP conduction using a one dimensional loop of the anatomical reentry in a cardiac tissue, quantitative correspondence between the hardware cable model and LR-I cable model was demonstrated with various conditions which are phase resetting by single impulsive stimulations and annihilations of the reentry by appropriately timed single stimulations.