Cardiovascular magnetic resonance in cardiac resynchronization therapy

Cardiovascular magnetic resonance (CMR) can inform on the aetiology of heart failure, global cardiac function, and myocardial viability, all of which are essential in cardiac resynchronization therapy (CRT). Late gadolinium enhancement (LGE)-CMR allows quantification of myocardial scarring and characterization of the pattern of scar, both of which may be useful in risk stratification. In addition, the ability of CMR to localize myocardial scar and provide reliable measures of segmental motion and deformation is being applied to targeting left ventricular lead deployment. The development of CMR-compatible devices may permit the use of CMR in the optimization of CRT after implantation.