Low-dimensional model of reentry in loop of cardiac cells

A low dimensional model (LD) using action potential duration (APD) and conduction time (ct) as functions of the diastolic interval (DIA) has been proposed to reproduce the dynamics of propagation in a loop of model cardiac cells (M. Courtemanche et al., 1966). For Beeler-Reuter type (BRT) ionic models, transition from regular to quasiperiodic (QP) propagation occurs at a critical length (L_crit). The authors show that the LD model predicts different forms of transition depending on the form of the APD(DIA) curve that they do not correspond to those observed in BRT ionic models. A modified LD model including the effect of neighbouring cells on the APD is shown to reproduce the dynamics of BRT ionic models