Effect of microscopic and macroscopic discontinuities on the response of cardiac tissue to defibrillating (stimulating) currents

Abstract

What transmembrane potentials are produced in cardiac tissue in response to the application of defibrillating (or stimulating) currents? Such transmembrane potentials are found here by means of an idealised one-dimensional model of cardiac tissue that incorporates intracellular and extracellular current flow paths and allows variable (intracellular) junction resistance. Markedly different transmembrane potentials were computed near the ends (compared with the centre) of 30- and 60-cell strands. With high junction resistance, periodic positive and negative transmembrane potentials occurred within each cell near the centre of the strand. The results in the aggregate paint a picture quite different from that of uniform depolarisation. © 1986 IFMBE.