Theoretical research on the influence of defibrillator paddle position on the human ventricular myocardium

Considering the high importance of the electrical defibrillation therapy and also the fact that the phenomena behind it have not been rotally explained, research in this urea is vitally needed. This article shows the reaction of a human ventricular myocardium to electrical stimuli applied through electrodes positioned in different places near to the myocardium. . The reaction was obtained using c1 mathematical computer simulation. The study was done with a model representing a threedimensional ellipsoidal section of human ventricular myocardial tissue immersed in bath. A realistic fiber orientation and curvature was implemented along with electrophysiological hetemgeneity. For obtaining information rtrictly related to the influence of paddles positioning, the cardiac muscle to which the electrical stimulus is applied is initially resting. A feature of interest wus the observation of the regions from which rhe wave fronts started to propagate. Regions, which contained cell uncoupling were also implemented. The temporal evolution of the transmembrane voltage was registered for around 500 ms. ir was observed that the existence of a region with cell uncoupling induces a diflerenr reaction of the myocardium to an electrical shock. Even though it could be of immediate help in cardiac defibrillation, it may reinduce fibrillation.