[A mathematical model of cardiac rhythm disorders in the presence of rapid auricular electrical activity]

The model is based on regularities of changes of the refractory period in the atrioventricular conductive system as well as changes of the delay of impulse conduction in this system during coupled electric stimulation of atria. With the aid of the model, the conditions of accurring heart-rate disturbances were considered (increase in the delay of the atrio-ventricular conduction, Wenkenbach's periodicity, fallin out of two, three or more successive excitations of the ventricles, etc.) on fast electric activity of the atria. Quantitative correlations were established between the parameters characterizing changes of the refractory period and the period of atrias excitations which produces a ventricles rhythm disturbance.