Impact of myocardial viability and left ventricular lead location on clinical outcome in cardiac resynchronization therapy recipients with ischemic cardiomyopathy.

Introduction: Cardiac resynchronization therapy (CRT) recipients with ischemic cardiomyopathy (ICM) have scar segments that may limit ventricular resynchronization and clinical response. The impact of myocardial viability at the left ventricular (LV) pacing site on CRT response is poorly elucidated.

Methods And Results: A retrospective cohort of 160 ICM patients with single photon emission computed tomography-myocardial perfusion imaging before device implantation were included.

Usefulness of low-dose dobutamine echocardiography to predict response and outcome in patients undergoing cardiac resynchronization therapy.

A substantial proportion of patients who meet the current guidelines for cardiac resynchronization therapy (CRT) fail to respond to this pacing modality. Although appropriate patient selection and left ventricular (LV) lead location have been ascribed as determinants of CRT response, the interaction among contractile reserve, dynamics of dyssynchrony, and lead location is not well understood. The present study prospectively evaluated the effect of contractile reserve and dobutamine-induced changes in LV synchrony, in relation to the LV lead location, as predictors of the response to CRT.

Interlead distance and left ventricular lead electrical delay predict reverse remodeling during cardiac resynchronization therapy.

Background: Both anatomic interlead separation and left ventricle lead electrical delay (LVLED) have been associated with outcomes following cardiac resynchronization therapy (CRT). However, the relationship between interlead distance and electrical delay in predicting CRT outcomes has not been defined.

Methods: We studied 61 consecutive patients undergoing CRT for standard clinical indications.