Author + information
- Received February 22, 2019
- Revision received June 10, 2019
- Accepted June 10, 2019
- Published online July 31, 2019.
- Dominique de Waard, BSca,
- Jaimie Manlucu, MDb,
- Anne M. Gillis, MDc,
- John Sapp, MDd,
- Jordan Bernick, MSe,
- Steve Doucette, MSf,
- Anthony Tang, MDb,
- George Wells, PhDe and
- Ratika Parkash, MD, MSd,∗ ()
- aFaculty of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada
- bLondon Health Sciences Center, University of Western Ontario, London, Ontario, Canada
- cLibin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada
- dQueen Elizabeth II Health Sciences Center, Halifax, Nova Scotia, Canada
- eOttawa Cardiovascular Research Methods Center, Ottawa, Ontario, Canada
- fResearch Methods Unit, Halifax, Nova Scotia, Canada
- ↵∗Address for correspondence:
Dr. Ratika Parkash, Department of Medicine, Queen Elizabeth II Heath Centre, Halifax Infirmary, 1796 Summer Street, Room 2501-D, Halifax, Nova Scotia B3H 3A7, Canada.
Objectives This study sought to evaluate the effect of cardiac resynchronization therapy with defibrillator (CRT-D) as compared with implantable cardioverter-defibrillator (ICD) on mortality, heart failure (HF) hospitalization, and ventricular arrhythmia in women versus men.
Background CRT-D has demonstrated reduced mortality and HF hospitalizations with greater benefit observed in women compared with men. However, whether CRT-D prevented ventricular arrhythmias in women compared with men was unclear.
Methods The RAFT (Resynchronization-Defibrillation for Ambulatory Heart Failure Trial) study randomized 1,798 patients to an ICD or CRT-D. In this post hoc analysis, women and men were compared by randomized group. By using a multivariable model, the outcomes of death and HF hospitalization and incidence of ventricular arrhythmia were compared between men and women.
Results There were 1,490 (83%) men (732, ICD; 758, CRT-D) and 308 (17%) women (172, ICD; 136, CRT-D) included in the analysis. Women with CRT-D had a significantly reduced incidence of death and HF hospitalization compared with men with CRT-D (hazard ratio: 0.52; 95% confidence interval: 0.33 to 0.81; p < 0.001) on multivariable analysis. Women with a primary prevention indication and CRT-D had the lowest rate of ventricular arrhythmia compared with men (hazard ratio: 0.59; 95% confidence interval: 0.39 to 0.91; p = 0.016).
Conclusions Women have improved rates of death and HF hospitalization with CRT-D and were less likely to experience ventricular arrhythmia when compared with men, after adjusting for differences in baseline characteristics over a prolonged follow-up. Whether these improved outcomes reflect inherent sex differences in the underlying myocardial substrate resulting in an enhanced response to CRT-D requires further research.
- cardiac resynchronization therapy with defibrillator (CRT-D)
- clinical trial
- heart failure
- ventricular arrhythmia
This work was supported by the Cardiac Arrhythmia Network of Canada. Dr. Manlucu has reported advisory board membership and consulting for Medtronic. Dr. Gillis has received research grants from Medtronic. Dr. Sapp has received research grants from Abbott and Biosense Webster; and has been a consultant for Biosense Webster; and has received honoraria from Abbott and Medtronic. Dr. Tang has received research grants from Medtronic. Dr. Parkash has received research grants from Medtronic and Abbott. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
The authors attest they are in compliance with human studies committees and animal welfare regulations of the authors’ institutions and Food and Drug Administration guidelines, including patient consent where appropriate. For more information, visit the JACC: Clinical Electrophysiology author instructions page.
- Received February 22, 2019.
- Revision received June 10, 2019.
- Accepted June 10, 2019.
- 2019 American College of Cardiology Foundation
This article requires a subscription or purchase to view the full text. If you are a subscriber or member, click Login or the Subscribe link (top menu above) to access this article.