Mechano-electric suppression of cardiac alternans

The annihilation of cardiac alternans is believed to be the first preventive action to halt the onset of ventricular fibrillation and sudden cardiac death. In this series of simulation studies, by means of boundary and spatially-distributed control, the alternans annihilation in a ID cable of cardiac cells is realized. The boundary control input is associated with a proportional perturbation feedback pacing-based controller input which is obtained by perturbation of basic pacing period through consecutive action potential duration (APD) measurements at the pacing site. The spatially-distributed actuation is associated with mechanically-based stimuli that modulate the internal calcium concentration of cells along the cable. Additionally, the amplitude of alternans nonlinear parabolic PDE with the full state feedback control associated with the ionic ID cardiac cell cable model is explored and analyzed. The alternans amplitude annihilation by a full state feedback in the nonlinear parabolic PDEs is in agreement with numerical results obtained from an ionic model of the ID cable of cardiac cells. Taken together, results from these simulation and analytical studies suggest a new mechano-electric based approach to the cardiac alternans annihilation.