Drs. Sebag and Martins share first authorship.
Reverse Electrical Remodeling by Cardiac Resynchronization Therapy: Prevalence and Clinical Impact
Article first published online: 14 JUN 2012
© 2012 Wiley Periodicals, Inc.
Journal of Cardiovascular Electrophysiology
Volume 23, Issue 11, pages 1219–1227, November 2012
How to Cite
SEBAG, F. A., MARTINS, R. P., DEFAYE, P., HIDDEN-LUCET, F., MABO, P., DAUBERT, J.-C. and LECLERCQ, C. (2012), Reverse Electrical Remodeling by Cardiac Resynchronization Therapy: Prevalence and Clinical Impact. Journal of Cardiovascular Electrophysiology, 23: 1219–1227. doi: 10.1111/j.1540-8167.2012.02376.x
Drs. Sebag and Martins report research grants from St. Jude Medical and Sorin Group. Dr. Daubert reports research grants from Medtronic and Medtronic Bakken Research Center; he is a consultant for Medtronic and St. Jude Medical. Dr. Leclercq reports research grants from Medtronic, St. Jude Medical, Biotronik, Sorin, and Boston Scientific; he is a consultant for Sorin, Medtronic, and St. Jude Medical. Other authors: No disclosures.
- Issue published online: 13 NOV 2012
- Article first published online: 14 JUN 2012
- Accepted manuscript online: 15 MAY 2012 12:30PM EST
- Manuscript received 25 March 2012; Revised manuscript received 23 April 2012; Accepted for publication 30 April 2012.
- bundle-branch block;
- cardiac resynchronization therapy;
- congestive heart failure;
- electrical remodeling;
- reverse remodeling
Intrinsic QRS Narrowing with CRT. Background: Cardiac resynchronization therapy (CRT) improves left ventricular ejection fraction (LVEF) in patients with congestive heart failure, LV systolic dysfunction, and a wide QRS complex. Previous reports suggest that CRT may also induce electrical remodeling but the impact on clinical outcome remains unknown.
Objective: We sought to determine (1) if chronic CRT induces a relevant shortening of the intrinsic QRS (iQRS), (2) whether changes in the native conduction system correlate with clinical or echocardiographic response to CRT, and (3) to identify predictors of iQRS width shortening.
Methods: We prospectively included 85 consecutive patients with left bundle-branch block who received a CRT device in 3 French centers. NYHA class, iQRS duration, LVEF, and left ventricular volumes were assessed before and 1 year after CRT implantation. Clinical and echocardiographic CRT responders were defined respectively as NYHA class improvement >1 class without heart failure hospitalization and an increase of LVEF by ≥10% and/or a decrease in LVESV by ≥15%. Electrocardiographic responders were defined as a decrease in iQRS duration by ≥20 ms.
Results: Baseline and 1-year follow-up mean iQRS durations were, respectively, 168.0 ± 19.7 ms and 149.6 ± 31.6 ms (P < 0.0001). Electrocardiographic response, observed in 43/85 patients (51%), was associated with a greater rate of clinical (P = 0.035) and echocardiographic (P = 0.023) response. Younger age, male gender, and longer baseline QRS width were independent predictors of electrocardiographic response.
Conclusion: CRT decreases iQRS duration. A reduction of at least 20 ms in iQRS duration is associated with better clinical and echocardiographic response. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1219–1227, November 2012)