Number:

Mech 170/97

Author(s):

VENDELIN, Marko.

Title:

Role of passive properties of tissue in cardiac impulse propagation through Purkinje-ventricular muscle junction. 16 p. + 6 p. fig.

Language:

English SUMMARY.The activation of the ventricular muscle is normally initiated through the Purkinje-ventricular muscle junctions. The propagation of the activation through the particular junction depends on the direction of the propagation and the frequency. This dependence may vary among the junctions. In this work the influence of the anatomical parameters, the junction density, conductivity and the coupling between the myocardium cells, to the activation propagation through the Purkinje-ventricular muscle junctions at the wide range of the activation frequencies is studied. The activation of the ventricular muscle is simulated by the bidomain model. According to the simulation results the parameters can be divided into two groups: (1) the junction density and (2) the junction conductance and the coupling between the myocardium cells. The variation of the junction density changes the amount of the current applied per cell in the tissue. It has been shown that the change of the activation pattern influenced by the variation of the density is negligible at most physiological states of the myocardium. The parameters from the second group, the coupling and the conductance, significantly influence the initialization of the activation. On the basis of this influence, the activation pattern of the ventricles may be changed due to the variation of the Purkinje-ventricular muscle junction conductance and the coupling between the myocardium cells. It is concluded that the possible local differences in the activation properties may be caused by the spatial variation in these anatomical parameters which mainly affect the initialisation of the activation.