Refining cardiac resynchronization therapy selection in borderline QRS duration patients
Date
2026-01-01
Journal Title
Journal ISSN
Volume Title
Citation Stats
Attention Stats
Abstract
Background Cardiac resynchronization therapy (CRT) improves outcomes in heart failure patients with left bundle branch block (LBBB) and QRS of ≥150 ms, but benefits with borderline QRS (120–149 ms) remain uncertain. Electrical (ED) and mechanical dyssynchrony (MD) may refine patient selection, although reliable predictors are lacking. Objective To examine clinical predictors of dyssynchrony in patients with borderline QRS duration (QRSd) undergoing CRT. Methods We retrospectively studied 336 CRT recipients (2006–2015). Vectorcardiograms quantified QRS area (QRSa), with ED defined as QRSa of ≥95 μVs. MD was assessed via speckle-tracking echocardiography. Logistic regression identified predictors of dyssynchrony. QRSa indexed to left ventricular end-diastolic volume (QRSa/LVEDV) was evaluated in logistic and Cox models, stratified by a QRSd of 150 ms threshold. Results ED and MD were present in 53.0% and 74.4% of patients. Shorter height was independently associated with ED, while female sex predicted MD. Among patients with QRSd of <150 ms, ED and MD were less prevalent, and height was the sole independent predictor of ED. Over a median follow-up of 28.3 months, 241 patients (71.7%) experienced a composite endpoint, with similar event rates between QRS subgroups. QRSa/LVEDV was the strongest predictor of MD (odds ratio: 26.83; P = .0004) and reduced risk of adverse outcomes (hazard ratio: 0.172; P = .0006) in the <150-ms subgroup, outperforming QRSd and sex. When MD was added, the QRSa/LVEDV association attenuated (hazard ratio: 0.35; P = .07). Conclusion Among LBBB patients with borderline QRSd, QRSa/LVEDV was more strongly associated with MD and outcomes than QRSd or other factors, supporting its potential role in refining patient selection.
Type
Department
Description
Provenance
Subjects
Citation
Permalink
Published Version (Please cite this version)
Publication Info
Jiang, H, Z Loring, N Varma, R Schaller, C Gilles, K Emerek, P Søgaard, C Polcwiartek, et al. (2026). Refining cardiac resynchronization therapy selection in borderline QRS duration patients. Heart Rhythm O2. 10.1016/j.hroo.2026.06.018 Retrieved from https://hdl.handle.net/10161/35613.
This is constructed from limited available data and may be imprecise. To cite this article, please review & use the official citation provided by the journal.
Collections
Endorsement
Review
Supplemented By
Referenced By
Scholars@Duke
Zak Loring
I am a cardiac electrophysiologist specializing in the treatment of heart rhythm disorders and management of cardiac implantable electronic devices (CIEDs). My research utilizes signal processing of electrocardiographic data and novel analytic techniques to better phenotype patients and identify those for whom interventional electrophysiology procedures may be most beneficial. This includes predicting which patients with left bundle branch block may benefit from early cardiac resynchronization therapy or conduction system pacing. I also analyze population level data to identify patients at high risk for adverse sequelae of rhythm disorders who may benefit from early intervention.
Marat Fudim
Joseph Andrew Kisslo
Dr. Kisslo's research has centered around the development and initial application of new ultrasound imaging devices. Focussed principally on morphologic diagnosis in the early years, the work has become progressively more physiologic in it's orientation.
After more than two decades there are now 300 original research papers, several textbooks and other materials. Dr. Kisslo has distinguished himself as the first to use phased array ultrasound imaging in the human body and, accordingly, was the first to describe most of the disease for which the technique is now commonplace. He was very early into the applications of Doppler color flow imaging and transesophageal imaging with ultrasound. He has served as an officer or on the Board of a variety of national and international bodies. He was one of the first President's of the American Society of Echocardiography. He reviews in all aspects of cardiac imaging, but principally echocardiography.
Over the past 15 years he has also had a keen interest in medical economics and has served on various professional and governmental boards in describing medical costs and dealing with medical economics. More recently, he has taken interest in adult re-education through remote learning means (telemedicine) and has become the Clinical Director of Telemedicine at Duke. He is Executive Producer of the world's largest telemedicine program (Echo in Context) which has run for the past 14 years. This was the first educational event to circumnavigate the globe live.
He is a frequent scientific and motivational lecturer to scientific organizations and industry. He serves as advisor to several governmental and industrial organizations.
Key words: Echocardiography, cardiac imaging, medical reimbursement, telemedicine, adult re-education.
Daniel Friedman
My research areas of interest include improving the safety and efficacy of complex ablation and optimal use of pacemakers in patients with heart failure, including cardiac resynchronization therapy and conduction system pacing. I am also interested in non-pharmacologic management of atrial fibrillation, including catheter ablation and left atrial appendage occlusion, and understanding optimal use of novel and emerging technologies.
Unless otherwise indicated, scholarly articles published by Duke faculty members are made available here with a CC-BY-NC (Creative Commons Attribution Non-Commercial) license, as enabled by the Duke Open Access Policy. If you wish to use the materials in ways not already permitted under CC-BY-NC, please consult the copyright owner. Other materials are made available here through the author’s grant of a non-exclusive license to make their work openly accessible.