Electrophysiological parameters in the electrical propagation during atrial fibrillation: A population of models study

Cardiac tissue conduction velocity (CV) is a relevant variable in the maintenance and stability of atrial fibrillation (AF). The main goal of this work is to investigate modulation of CV in human chronic AF by inter-subject variability in ionic channel properties, cellular environmental factors and tissue coupling, by using a population of mathematical models. A monodomain tissue model was developed on the basis of the Skibsbye human atrial cell model. In this model, nine parameters are varied leading to a total number of 500 tissue models (8×156 cells). Among these simulations, 126 models are found within the experimental physiological range of biomarkers obtained from 149 chronic AF patients. The resulting population of 126 tissue models covers the variability in the biomarkers observed in the experimental recordings. The specific balance between sodium current and diffusion coefficient modulates the CV, critical for arrhythmia inducibility. The developed population of tissue models establishes the basis for further research in ionic mechanisms that facilitate AF maintenance and in-silico evaluation of personalised drug treatments.