Author + information
- Received June 27, 2012
- Revision received October 11, 2012
- Accepted November 8, 2012
- Published online March 5, 2013.
- Valentina Kutyifa, MD*,†,* (, )
- Axel Kloppe, MD‡,
- Wojciech Zareba, MD, PhD*,
- Scott D. Solomon, MD§,
- Scott McNitt, MS*,
- Slava Polonsky, MS*,
- Alon Barsheshet, MD*,
- Bela Merkely, MD, PhD†,
- Bernd Lemke, MD‡,
- Vivien Klaudia Nagy, MD†,
- Arthur J. Moss, MD* and
- Ilan Goldenberg, MD*
- ↵*Reprint requests and correspondence:
Dr. Valentina Kutyifa, Heart Research Follow-up Program, Cardiology Division, University of Rochester Medical Center, 265 Crittenden Boulevard, Box 653, Rochester, New York 14642
Objectives The goal of this study was to evaluate the influence of left ventricular (LV) lead position on the risk of ventricular tachyarrhythmia in patients undergoing cardiac resynchronization therapy (CRT).
Background Left ventricular ejection fraction (LVEF) is a surrogate marker of heart failure (HF) status and associated risk. Data on the effectiveness of cardiac resynchronization therapy with defibrillator (CRT-D) in patients with mild HF and better LVEF are limited.
Methods In the MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy) study, the echocardiography core laboratory assessed baseline LVEF independent of the enrolling centers and identified a range of LVEFs, including those >30% (i.e., beyond the eligibility criteria). Echocardiographic response with CRT, defined as percent change in left ventricular end-diastolic volume (LVEDV), was analyzed in 3 prespecified LVEF groups: >30%, 26% to 30%, and ≤25%. The primary endpoint was HF or death. Secondary endpoint included all-cause mortality.
Results LVEF was evaluated in 1,809 study patients. There were 696 (38%) patients with LVEF >30% (in the range of 30.1% to 45.3%); 914 patients (50.5%) with LVEF 26% to 30%; and 199 patients with LVEF ≤25% (11%). The mean reduction in LVEDV with CRT-D therapy at the 1-year follow-up was directly related to increasing LVEF (LVEF >30%: 22.3%; LVEF 26% to 30%: 20.1%; and LVEF ≤25%: 18.7% reduction, respectively [p = 0.001]). CRT-D treatment similarly reduced the risk of HF/death in patients with LVEF >30% (hazard ratio [HR]: = 0.56 [95% confidence interval (CI): 0.39 to 0.82], p = 0.003), LVEF 26% to 30% (HR: 0.67: [95% CI: 0.50 to 0.90], p = 0.007), and LVEF ≤25% (HR: 0.57 [95% CI: 0.35 to 0.95], p = 0.03; all p values for LVEF-by-treatment interactions >0.1).
Conclusions In MADIT-CRT, the clinical benefit of CRT was evident regardless of baseline LVEF, including those with LVEF >30%, whereas the echocardiographic response was increased with increasing LVEF, indicating that CRT might benefit patients with better LVEF. (Multicenter Automatic Defibrillator Implantation With Cardiac Resynchronization Therapy [MADIT-CRT]; NCT00180271)
- cardiac resynchronization therapy
- heart failure
- implantable cardioverter-defibrillator
- left ventricular ejection fraction
The MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy) study was supported by a research grant from Boston Scientific to the University of Rochester School of Medicine and Dentistry. Dr. Kutyifa has received honoraria from Servier and research support from Boston Scientific. Dr. Merkely is a member of the speaker's bureau for Boehringer-Ingelheim; and has received honoraria/consultant fees from Biotronik, Medtronic, and St. Jude Medical. Drs. Zareba and Solomon have received research grants from Boston Scientific. Drs. Moss and Goldenberg have received research grants. All others authors have reported that they have no relationships relevant to the contents of this paper to disclose. The first 2 authors contributed equally to the original concept and to authorship of this investigation.
- Received June 27, 2012.
- Revision received October 11, 2012.
- Accepted November 8, 2012.
- American College of Cardiology Foundation