105 Investigation of the transmural action potential duration and repolarization properties of scar borderzone in patients undergoing ventricular tachycardia ablation

Background: Dispersion of action potential duration (APD) and repolarization are important factors in the genesis of ventricular arrhythmia, facilitating functional block and reentry. Present substrate mapping of VT not only fails to account for repolarization of the tissue, but assesses scar/voltage in a planar fashion. However, arrhythmias within the heart do not traverse a one-dimensional course. It is highly likely that the wavefront is heterogeneous, taking complex paths involving endocardium, mid-myocardium and epicardium. The transmural differences of action potential duration (APD), across scar borderzone,  are poorly defined in the intact human heart. Heterogeneity in APD and total repolarization time (RT) across the ventricular wall may play an important part in the generation and sustainment of three-dimensional ventricular tachycardia (VT) circuits. 
Source: Europace - Category: Cardiology Source Type: research