Author + information
- Received June 2, 2011
- Revision received July 25, 2011
- Accepted July 27, 2011
- Published online October 1, 2011.
- Erberto Carluccio, MD,
- Paolo Biagioli, MD,
- Gianfranco Alunni, MD,
- Adriano Murrone, MD,
- Paola Pantano, MD,
- Emilia Biscottini, MD,
- Cinzia Zuchi, MD,
- Gianluca Zingarini, MD,
- Claudio Cavallini, MD and
- Giuseppe Ambrosio, MD, PhD⁎ ()
- ↵⁎Reprint requests and correspondence:
Dr. Giuseppe Ambrosio, Cardiologia e Fisiopatologia Cardiovascolare, Ospedale S.M. della Misericordia, S. Andrea delle Fratte, 06131 Perugia, Italy
Objectives The aim of this study was to evaluate whether, in patients with evidence of both electrical and mechanical left ventricular (LV) dyssynchrony, extensive LV dilation would affect response to cardiac resynchronization therapy (CRT).
Background Cardiac resynchronization therapy is effective in heart failure patients with LV dysfunction and wide QRS complex. However, many patients still fail to respond. We hypothesized that presence of extensive LV dilation might prevent response to CRT, despite LV mechanical dyssynchrony.
Methods We studied 78 heart failure patients (68 ± 9 years of age, 77% men) with both electrical (QRS width >120 ms) and mechanical intraventricular dyssynchrony (by tissue Doppler imaging and/or left lateral wall post-systolic contraction). Echocardiographic evaluation was performed at baseline and 6 to 8 months after CRT. As an indication of LV remodeling, end-diastolic volume index and end-systolic volume index (ESVI) and sphericity index were measured. Long-term (40 ± 23 months) clinical follow-up (events: cardiac death and hospital admission for heart failure) was also obtained.
Results At follow-up after CRT, in the overall population, ejection fraction increased from 26 ± 6% to 35 ± 11% (p < 0.0001), whereas end-diastolic volume index (from 144 ± 43 ml/m2 to 119 ± 55 ml/m2), ESVI (from 108 ± 37 ml/m2 to 82 ± 49 ml/m2, p < 0.0001 for both), and sphericity index (from 0.60 ± 0.22 to 0.53 ± 0.15, p = 0.0036) all significantly decreased. By multiple linear regression analysis, after controlling for confounding factors, change in LV ejection fraction at follow-up resulted independently and negatively associated with baseline ESVI (p = 0.001), with much lower improvement after implant in the highest tertile of baseline ESVI. During follow-up, 31 patients (39.7%) had a cardiac event. By Cox regression model, baseline ESVI was the most powerful predictor of events, with event-rate/year increasing with increasing tertiles of ESVI (6.3%, 10.1%, and 23.8%, respectively, p < 0.05).
Conclusions In this nonrandomized, open-label clinical study, despite intraventricular electrical and mechanical dyssynchrony, extensive LV remodeling at baseline negatively impacted CRT results in terms of LV function improvement and incidence of cardiac events at follow-up.
Dr. Ambrosio serves on the Advisory committee and Speakers' Bureau for Menarini International and Schering Plough. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
Presented in part at the European Society of Cardiology Congress, Barcelona, August 2009.
- Received June 2, 2011.
- Revision received July 25, 2011.
- Accepted July 27, 2011.
- American College of Cardiology Foundation