Patterns stability in cardiac tissue under spatial electromagnetic radiation

Abstract

The electric activity in myocardial tissue is controlled by the target waves emitted from the sinoatrial node and then the Calcium flow is controlled to regulate the heartbeat. The occurrence of local defects can block the wave propagation in the cardiac tissue and then the heartbeat can be disturbed completely. During the electrophysiological activity including stochastic diffusion of intracellular ions and continuous exchange of extracellular ions along ion channel embedded in the cell membrane, electromagnetic induction occurs in the cardiac tissue and the involvement of external electromagnetic radiation can change the excitability and the neural activities. In this paper, based on a memristive cardiac tissue model by incorporating magnetic flux variable and induction current into the two-variable cardiac model for discerning cardiac excitation, spatial electromagnetic radiation is applied to investigate the stability and propagation of waves in the cardiac tissue. Wave propagation in the reaction-diffusion equations for cardiac tissue is approached by an equivalent diffusive neural network on square array after discretization. Local heterogeneity is produced by introducing diversity in initial value for inducing spiral seed, and stable spiral waves are developed as initial states, which represent tachycardia and arrhythmia in the cardiac tissue. It is found that symmetric spatial patterns can be controlled by the external electromagnetic radiation, in particular, nonlinear resonance is enhanced and specific spatial patterns are developed under noisy radiation.