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
- Fernandez-Armenta J et al. Substrate modification or ventricular tachycardia induction, mapping, and ablation as the first step? A randomized study. Heart Rhythm 2016;13:1589-1595.