Multidirectional Stimulation in an Isolated Murine Heart: A Computational Model

Abstract

It is common to use very high electric fields (E) to defibrillate hearts, which can damage cardiomyocytes, showing the importance of developing methods that can decrease the E applied in defibrillation protocols. We used COMSOL Multiphysics software to model, simulate, and analyze the application of an E in an isolated heart with monodirectional and multidirectional stimuli, using 2 pairs of electrodes and the superposition principle as a way to decrease the E applied and reduce the required number of stimulation electrodes. When applying an E of 3 V/cm in the 0°, 30°, and 60° directions, individually in the stimulation chamber, E was equal to 3.2 V/cm and its phases were equal to 0°, 30°, and 60°, respectively, validating the superposition principle. We observed a reduction up to 31.8% in | E| when applying a multidirectional stimulus when comparing to the monodirectional stimulus, in order to stimulate the same area of the heart. For the same amount of stimuli directions, we obtained up to 11.7% reduction of | E|, just by modifying the directions of the applied stimuli. In the simulation developed in this work, the superposition principle was validated in a stimulation chamber. For the same stimulated area, the multidirectional E has been always lower than the monodirectional. We observed that, in order to decrease the intensity of E, both the number of applied stimuli and their directions were relevant issues.