Echocardiography-guided left ventricular lead placement for cardiac resynchronization therapy in ischemic vs nonischemic cardiomyopathy patients

Abstract

Background: Echocardiography-guided (EG) left ventricular (LV) lead placement at the site of latest mechanical activation improves outcome in heart failure (HF) patients receiving a cardiac resynchronization therapy (CRT)-defibrillator (CRT-D).

Objective: The purpose of this study was to examine the effect of a strategy of EG LV lead placement in each of ischemic (ICM) vs nonischemic (NICM) cardiomyopathy patients.

Methods: Patients enrolled in the Speckle Tracking Assisted Resynchronization Therapy for Electrode Region (STARTER) prospective, randomized trial who were treated with a CRT-D device (108 EG strategy and 75 routine strategy) were followed to the end-points of death, appropriate CRT-D therapy, or HF hospitalization.

Results: Of the patients enrolled in STARTER, 115 had ICM and 68 had NICM. Over mean follow-up of 3.7 ± 2.1 years, 62 patients died, 40 received appropriate CRT-D therapy, and 67 had HF hospitalizations. Compared to NICM patients, patients with ICM had worse survival (P = .0003), worse survival free from implantable cardioverter-defibrillator therapy (P = .004), and survival free from HF hospitalization (P = .0001). A strategy of EG LV lead placement improved the outcome of CRT-D therapy-free survival primarily in ICM patients and the outcome of HF hospitalization-free survival in both ICM and NICM patients. Achieving LV resynchronization was most critical in ICM patients in whom arrhythmic and HF outcomes improve with resynchronization to levels comparable to those of NICM patients.

Conclusion: A strategy of EG LV lead placement improves HF-free survival equally in ICM and NICM patients and CRT-D therapy-free survival more favorably in ICM patients to levels comparable to those of NICM patients.

Keywords: Cardiac resynchronization therapy; Cardiomyopathy; Death; Defibrillator therapy; Targeted lead placement.