Model of unidirectional block formation leading to reentrant ventricular tachycardia in the infarct border zone of postinfarction canine hearts
Ventricular tachycardia is common after myocardial infarction and it is a serious health problem worldwide. The source of reentrant ventricular tachycardia is often located in the infarct border zone, the layer of thin surviving myocardium adjacent to the infarct. Although there is electrical activity occurring in the infarct border zone, the conduction velocity of the leading edge of the propagating wavefront is not constant. Where the infarct border zone dimension changes from thin-to-thick in the travel direction, very slow conduction or even functional block occur at locations where the wavefront becomes critically convex. In this study, the activation rate and IBZ geometric structure necessary for functional block to form during premature stimulation and during reentrant ventricular tachycardia, are determined.
unidirectional block ventricular tachycardia activation mapping isthmus wavefront curvature