Guaranteed Defibrillation on a Cardiomyocyte Model

On the model of cardiomyocyte under the influence of simulated fibrillation, the dependences of the threshold energy of guaranteed defibrillation on the duration of the defibrillation pulse of a half-sine and rectangular waveform are studied. Guaranteed defibrillation is achieved when a defibrillation pulse causes an extension of the current refractory period of cardiomyocytes to a pulse repetition period of fibrillation or more. In this case, the propagation of the fibrillation wave through the myocardium becomes impossible. The obtained dependences of the threshold energy of guaranteed defibrillation on the duration of the defibrillation pulse correspond to the Hoorweg-WeissLapicque law on a limited range of relative values of the pulse duration. For a rectangular pulse, this range is much wider than for a half-sine pulse. The obtained dependence of the threshold energy of guaranteed defibrillation on the duration of a half-sine defibrillation pulse is close to the results of animal experiments. Therefore, the guaranteed defibrillation mechanism can be used to compare the energy efficiency of external defibrillation pulses.