title: Usefulness of echocardiographically guided left ventricular lead placement for cardiac resynchronization therapy in patients with intermediate QRS width and non-left bundle branch block morphology.
abstract: The current guidelines most strongly support cardiac resynchronization therapy (CRT) for patients with heart failure with a QRS width of ≥150 ms and left bundle branch block (LBBB). Our objective was to assess the potential benefit of echocardiographically guided left ventricular (LV) lead positioning for patients with a QRS width <150 ms or non-LBBB as a substudy of the Speckle Tracking Assisted Resynchronization Therapy for Electrode Region (STARTER) prospective, randomized controlled trial. The STARTER trial randomized 187 patients with heart failure, a QRS of ≥120 ms, and ejection fraction of ≤35% to LV lead guided to the site of latest mechanical activation by speckle tracking radial strain versus routine implantation. The predefined primary end point was heart failure hospitalization or death within 2 years. This substudy included 151 CRT patients with matching echocardiographic and LV lead position data and complete follow-up data. Patients with a QRS width of 120 to 149 ms or non-LBBB and LV lead concordant or adjacent to the site of latest mechanical activation had favorable outcomes after CRT similar to those with LBBB or a QRS width of ≥150 ms. In contrast, patients with a QRS of 120 to 149 ms or non-LBBB and remote LV leads had unfavorable outcomes (hazard ratio 5.45, 95% confidence interval 2.36 to 12.6, p <0.001, and hazard ratio 4.92, 95% confidence interval 2.12 to 11.39, p <0.001, respectively, with significant interaction after adjusting for baseline variables, p = 0.038 and p = 0.008). In conclusion, LV lead positioning with respect to the echocardiographic site of latest activation was significantly associated with more favorable clinical outcomes in patients with a QRS duration <150 ms and/or non-LBBB. Additional prospective study is warranted.
authors.affiliation: Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
authors.forename: Josef J
authors.initials: JJ
authors.lastname: Marek
authors.affiliation: Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
authors.forename: Samir
authors.initials: S
authors.lastname: Saba
authors.affiliation: Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
authors.forename: Tetsuari
authors.initials: T
authors.lastname: Onishi
authors.affiliation: Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
authors.forename: Keiko
authors.initials: K
authors.lastname: Ryo
authors.affiliation: Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
authors.forename: David
authors.initials: D
authors.lastname: Schwartzman
authors.affiliation: Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
authors.forename: Evan C
authors.initials: EC
authors.lastname: Adelstein
authors.affiliation: Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania. Electronic address: gorcsanj@upmc.edu.
authors.forename: John
authors.initials: J
authors.lastname: Gorcsan
mesh_terms: D000368:Aged; D002037:Bundle-Branch Block / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D058406:Cardiac Resynchronization Therapy / Q000379:methods*; D004311:Double-Blind Method; D004452:Echocardiography / Q000379:methods*; D004562:Electrocardiography; D004567:Electrodes, Implanted; D005260:Female; D005500:Follow-Up Studies; D006352:Heart Ventricles; D006801:Humans; D008297:Male; D011446:Prospective Studies; D025321:Surgery, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome