Author + information
- Received December 29, 2018
- Revision received February 17, 2019
- Accepted April 2, 2019
- Published online June 17, 2019.
- Hiro Kawata, MD, PhDa,b,∗ (, )
- Haikun Bao, PhDc,
- Jeptha P. Curtis, MDc,d,
- Karl E. Minges, PhD, MPHc,d,
- Teferi Mitiku, MDa,
- Ulrika Birgersdotter-Green, MDe,
- Gregory K. Feld, MDe and
- Jonathan C. Hsu, MD, MASe
- aDepartment of Cardiology, University of California, Irvine, Orange, CaliforniaDepartment of Cardiology, University of California, Irvine, Orange, California
- bOregon Heart and Vascular Institute, Springfield, OregonOregon Heart and Vascular Institute, Springfield, Oregon
- cCenter for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, ConnecticutCenter for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, Connecticut
- dSection of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, ConnecticutSection of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut
- eCardiac Electrophysiology Section, Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla, CaliforniaCardiac Electrophysiology Section, Division of Cardiology, Department of Medicine, University of California, San Diego, La Jolla, California
- ↵∗Address for correspondence:
Dr. Hiro Kawata, Oregon Heart and Vascular Institute, Peacehealth Sacred Heart Medical Center, 3311 Riverbend Drive, Springfield, Oregon 97477.
Background The benefits of cardiac resynchronization therapy (CRT) in patients with non-left bundle branch block (LBBB) conduction abnormality have not been fully explored.
Objectives This study sought to evaluate clinical outcomes among Medicare-aged patients with nonspecific intraventricular conduction delay (NICD) versus right bundle branch block (RBBB) in patients eligible for implantation with a CRT with defibrillator (CRT-D).
Methods Using the National Cardiovascular Data Registry implantable cardioverter-defibrillator (ICD) registry data between 2010 and 2013, the authors compared outcomes in CRT-eligible patients implanted with CRT-D versus ICD-only therapy among patients with NICD and RBBB. Also, among all CRT-D–implanted patients, the authors compared outcomes in those with NICD versus RBBB. Survival curves and multivariable adjusted hazard ratios (HRs) were used to assess outcomes including hospitalization and death.
Results In 11,505 non-LBBB CRT-eligible patients, after multivariable adjustment, among patients with RBBB, CRT-D was not associated with better outcomes, compared with ICD alone, regardless of QRS duration. Among patients with NICD and a QRS ≥150 ms, CRT-D was associated with decreased mortality at 3 years compared with ICD alone (HR: 0.602; 95% confidence interval [CI]: 0.416 to 0.871; p = 0.0071). Among 5,954 CRT-D–implanted patients, after multivariable adjustment NICD compared with RBBB was associated with lower mortality at 3 years in those with a QRS duration of ≥150 ms (HR: 0.757; 95% CI: 0.625 to 0.917; p = 0.0044).
Conclusions Among non-LBBB CRT-D–eligible patients, CRT-D implantation was associated with better outcomes compared with ICD alone specifically in NICD patients with a QRS duration of ≥150 ms. Careful patient selection should be considered for CRT-D implantation in patients with non-LBBB conduction.
- cardiac resynchronization therapy defibrillator
- National Cardiovascular Data Registry
- non-left bundle branch block
- nonspecific interventricular conduction delay
- right bundle branch block
This research was supported by the American College of Cardiology Foundation’s National Cardiovascular Data Registry (NCDR). Dr. Curtis has received financial support from the American College of Cardiology and the Centers for Medicare & Medicaid Services. Dr. Minges has received salary support to perform analyses on behalf of the ACC NCDR. The views expressed in this paper represent those of the authors, and do not necessarily represent the official views of the NCDR or its associated professional societies identified at www.ncdr.com. The NCDR ICD Registry is an initiative of the American College of Cardiology Foundation with partnering support from the Heart Rhythm Society. Dr. Curtis holds equity interest in Medtronic. Dr. Mitiku has received honoraria from Abbott. Dr. Birgersdotter-Green has received honoraria for consulting from Medtronic, Abbott, and Biotronik. Dr. Feld has received EP Fellowship Training Program stipends from Medtronic, Abbott/St. Jude Medical, Biotronik, Boston Scientific, and Biosense Webster; holds stock options in Medwaves, Acutus, Perminova, and toSense; has served on Scientific Advisory Boards for Medwaves and Acutus; is cofounder of Perminova; and has received research support from Circa Scientific. Dr. Hsu has received honoraria from Medtronic, Abbott, Boston Scientific, Biotronik, Bristol-Myers Squibb, and Janssen Pharmaceuticals; and has received research grants from Biosense Webster and Biotronik. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
Listen to this manuscript's audio summary by Editor-in-Chief Dr. Valentin Fuster on JACC.org.
- Received December 29, 2018.
- Revision received February 17, 2019.
- Accepted April 2, 2019.
- 2019 American College of Cardiology Foundation
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