When do you consider epicardial mapping for ventricular tachycardia (VT)?
Mapping and ablation of ventricular tachycardia (VT) is usually done from the endocardial approach except in the following specific situations:
- VT in structural heart diseases with a propensity for an epicardial substrate like Chagas disease and arrhythmogenic right ventricular cardiomyopathy (ARVC/ARVD)
- Hyperenhancement seen in the epicardial region on contrast enhanced cardiac magnetic resonance (CMR) imaging
- Endocardial mapping fails to identify an endocardial scar
- Electrocardiographic features of clinical or induced VT indicating an epicardial focus
- Failed attempt at ablation by endocardial approach
- Fernández-Armenta J, Penela D, Acosta J, Andreu D, Evertz R, Cabrera M, Korshunov V, Vassanelli F, Martínez M, Guasch E, Arbelo E, María Tolosana J, Mont L, Berruezo A. Substrate modification or ventricular tachycardia induction, mapping, and ablation as the first step? A randomized study. Heart Rhythm 2016;13:1589-1595.