Retrospective studies have documented an improved response rate to CRT when the LV lead is placed in a myocardial region with late electrical activation and without scar tissue (8,9). Furthermore, lack of electrical resynchronization after CRT illustrated by unchanged or prolonged QRS duration is associated with poor clinical outcome (10) and programming the interventricular (VV) delay to obtain the narrowest QRS-complex has been suggested to increase CRT response rate (11,12).