Simulation of Intra-Cardiac Complex Impedance Signals for Developing Simple Bio-impedance Models for Cardio-Dynamics

In this study computer models are used for simulating electrical impedance signals from intracardiac catheter inserted to the bottom of the left ventricle of the heart. 3D dynamic heart is composed of dynamic spline surfaces. Impedance signals from the catheter electrodes are calculated with finite difference method using complex tissue impedance values at frequencies 1 kHz and 1 MHz. The results of the FDM modeling were compared with a simple 3-element equivalent circuit model where also a parameter change has been introduced. The impedance results exhibited significantly similar details once plotted on Nyquist real-imaginary plot. From those similarities we conclude, that it is worthwhile to continue research in this area and aim to develop a few-element electrical circuit model for whole organ impedance