Author + information
- Xuping Li1,3,
- Mei Yang2,3,
- Dachun Yang3,
- Shenghua Zhou1,
- Jingjun Liang3,
- Gang Wu3,
- Paul A. Friedman2 and
- Yong-Mei Cha2
- 1From the *Department of Cardiovascular medicine, The Second Xiangya Hospital, Central South University, Changsha, China
- 2Department of Cardiology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- 3Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA
Cardiac resynchronization therapy (CRT) improves left ventricular remodeling and depressed systolic function. However, little is known whether ventricular conduction is a physiological marker of electrical reverse remodeling. To determine the relationship between CRT response and shortening the wide QRS duration.
A consecutive 114 patients who underwent CRT with a defibrillator (CRT-D) implantation between January 2002 and December 2012 and had subsequent generator replacement (GR) were included in the study. Patients had left ventricular ejection fraction (LVEF) ≥50% at the time of GR was defined as super-responders. Patients with LVEF change >5% and LVEF 36-49% at the GR was defined as moderate-responders and the rest patients as non-responders.
Of the 114 patients, there were 58 (50.9%) non-responders, 29 (25.4%) responders, and 27 (23.7%) super-responders. A significant QRS shortening at 3-month follow-up was observed in super-responders (from 175.4±21.4ms to 159.7±20.7ms, p=0.001) and moderate-responders (from 169.0±21.3ms to 157.7±17.6ms, p=0.008). At the time of GR, only super-responders (from 159.7±20.7ms to 146.3±19.2ms, p<0.0001) had a significant QRS shortening from 3-month follow-up. Late QRS change emerged as an independent predictors of super-response to CRT (HR=1.19 for every 5ms decrease, 95%CI: 1.04-1.37, p=0.013).
Continuous QRS shortening late after CRT implant predicts super-response.