Examples of substrate modification in patients with VTs after previous myocardial infarction. Panels A to C show LV voltage maps in the right anterior oblique view in a patient with an extensive anteroseptal scar. Panels D to F depict LV voltage maps in posterior view in a patient after inferolateral myocardial infarction. Note the elimination of local voltage within the ablated zone after either core scar isolation (panel B) or substrate homogenization (panel E).