A space-fractional framework for cardiac electrophysiology modeling

Description

Microscopic structural features of cardiac tissue play a fundamental role in determining complex spatio-temporal excitation dynamics at the macroscopic level. When studying electrical propagation in cardiac tissue, microscopic structural heterogeneity is often neglected in modeling electrical propagation at the macroscopic scale, thus hindering the investigation and characterization of cardiac conduction modulation due to the composite tissue microstructure. Recent efforts have been devoted to the development of mathematical models accounting for non-local spatio-temporal coupling able to capture these complex dynamics without the need of resolving tissue heterogeneities down to the micro-scale. In this talk, a novel mathematical formulation will be presented for cardiac electrophysiology modeling and simulation, that incorporates spatially non-local couplings within a physiological reaction–diffusion scenario. First, the coupling of structural anisotropy and tissue heterogeneity via a nonlocal modification of the classical Monodomain model, obtained by a fractional power of its diffusive term, will be discussed from both the modeling and computational aspect. The resulting nonlocal model describes different levels of tissue heterogeneity as the fractional exponent is varied. Then, its generalization to a space-fractional Bidomain framework will be presented. Numerical studies for one dimensional excitation patterns demonstrate that (i) symmetric properties occur in the conductivity parameters' space, (ii) the degree of non-local coupling affects the onset and evolution of discordant alternans dynamics, and (iii) the theoretical framework fully recovers classical formulations and is amenable for parametric tuning relying on experimental conduction velocity and action potential morphology.

Period	20 Apr 2023
Event title	2nd SFB International Workshop 2023 - "Taming Complexity in Partial Differential Systems"
Event type	Conference
Location	AustriaShow on map