Model-based control of cardiac dynamics in a ring geometry
Cardiac tissue is an excitable medium which supports propagation of nonlinear excitation waves of cellular polarization (action potential) and ionic fluxes. In certain parameter regimes, regular wavetrains characteristic of normal (sinus) heart rhythm destabilize in favor of an arrhythmic behavior. Cardiac arrhythmias such as alternans (a beat-to-beat variation of the action potential duration) are known precursors to the ventricular fibrillation, a behavior similar to fluid turbulence, which is lethal unless immediately treated. This connection motivated intensive experimental and theoretical studies of arrhythmias in recent years.
In this talk we present our results on suppression, using different
feedback control schemes, of arrhythmia in the Fenton-Karma model of cardiac tissue. Specifically, we compare non-model-based control (e.g., time-delay autosynchronization) with model-based control approaches in a one-dimensional ring geometry. In both cases, arrhythimic behavior can be eliminated by an appropriate current injected locally (e.g., through a microelectrode) into the tissue. However, model-based control achieves this goal faster and with a lower risk of tissue damage due to a much weaker control current.