Activation signatures for identifying critical isthmi of ventricular tachyarrhythmias

Abstract

Mapping scar-mediated ventricular tachycardia (VT) is a serious concern in ischemic cardiomyopathy due to the precarious hemodynamic situation. The target of such a procedure is mainly to identify the isthmus whose existence is critical to the perpetuation of the reentry. The goal of mapping is, thus, to identify the isthmus for ablation, to break the loop of electrical reactivation and will remain the reference standard as defined by Mark Josephson. 1 However, the hemodynamic compromise and subsequent renal dysfunction, lead most centers now to consider a substrate based approach. Substrate approaches that have been proposed to identify VT ablation targets include isochronal crowding, 2 pacing approaches such as DEEP, 3 reentry vulnerability index, 4 wall thickness maps, 5 and computer simulations. 6 Factors which complicate the analysis in patients