Patient oriented model of atrioventricular reentrant tachycardia and of its termination by overdrive on-circuit pacing

A computer model is used to reproduce atrioventricular (AV) reentrant tachycardia in order evaluate the possibility of its termination by overdrive `on-circuit´ pacing. The model simulates activation waves radiating along a one-dimensional circular pathway composed of 289 elements. Experiments examined the capability of overdrive on-circuit pacing to terminate the tachycardia and its dependence on various factors. The results suggest the following: (A) the general impression of a regular recovery wave and of a regular excitable window moving uniformly along the macroreentrant circular path is incorrect; (B) the use of overdrive bursts of several stimuli with a short coupling interval has unpredictable effects; and (C) the use of bursts with coupling interval only slightly shorter than the tachycardia cycle length is more safe (with respect to tachycardia reinitiation) and for certain combinations of the coupling interval and cycle length, prolonged bursts do not reinitiate the tachycardia