Exit sites on the epicardium rarely subtend critical diastolic path of ischemic VT on the endocardium: Implications for noninvasive ablation.

The epicardial exit site and the mid-diastolic isthmus sites were spatially distant and discrepant. Surface electrocardiography (ECG)-derived strategy in identifying epicardial exit site to select noninvasive ablation targets is prone to identify epicardial exit sites and may not identify critical targets in ischemic scar VT.