The role of non-invasive imaging in patient selection.

Cardiac resynchronization therapy (CRT) is an established therapy for patients with advanced heart failure, depressed left ventricular (LV) function and wide QRS complex. A substantial amount of patients do not respond to CRT. Recent studies suggest that assessment of mechanical dyssynchrony may allow identification of potential CRT responders. In addition, presence of scar tissue and venous anatomy may play a role in the selection of candidates. This article summarizes the role of non-invasive cardiac imaging modalities addressing these issues in the selection of CRT candidates.