Author + information
- Received January 14, 2011
- Revision received February 16, 2011
- Accepted February 24, 2011
- Published online July 1, 2011.
- Hsin-Yueh Liang, MD⁎,†,
- Alan Cheng, MD⁎,
- Kuan-Cheng Chang, MD†,
- Ronald D. Berger, MD⁎,
- Kunal Agarwal⁎,
- Patrick Eulitt⁎,
- Mary Corretti, MD⁎,
- Gordon Tomaselli, MD⁎,
- Hugh Calkins, MD⁎,
- David A. Kass, MD⁎ and
- Theodore P. Abraham, MD⁎,⁎ ()
- ↵⁎Reprint requests and correspondence:
Dr. Theodore P. Abraham, Johns Hopkins University, 600 North Wolfe Street, Carnegie 568, Baltimore, Maryland 21287
Objectives The aim of this study was to evaluate atrial and ventricular function in patients undergoing cardiac resynchronization therapy (CRT).
Background Right atrial pacing (AP) in CRT induces delays in electrical and mechanical activation of the left atrium. The influence of atrial sensing (AS) versus AP on ventricular performance in CRT and the mechanisms underlying the differences between AS and AP in CRT have not been fully elucidated.
Methods Fifty-five patients with heart failure undergoing CRT for 9 ± 12.5 months and 22 control subjects without heart failure were enrolled. Conventional and tissue Doppler echocardiography was performed to examine atrial and ventricular mechanics and hemodynamic status.
Results The optimal atrioventricular interval was shorter in AS compared with AP mode (126 ± 19 ms vs. 155 ± 20 ms, p < 0.0001). Left ventricular (LV) outflow tract time-velocity integral (22 ± 7 cm vs. 20 ± 7 cm, p < 0.001), diastolic filling period (468 ± 124 ms vs. 380 ± 93 ms, p < 0.001), and global strain (−32 ± 24% vs. −27 ± 22%, p = 0.001) were greater in AS compared with AP mode. Atrial strain was higher in AS compared with AP mode in the right atrium (−28.2 ± 8.6% vs. −22.6 ± 7.6%, p = 0.0007), interatrial septum (−17.1 ± 6.5% vs. −13.2 ± 5.4%, p = 0.002), and left atrium (−16.4 ± 11.0% vs. −13.6 ± 8.5%, p = 0.02). There was no difference in intraventricular dyssynchrony but significantly lower atrial dyssynchrony in AS compared with AP mode (31 ± 19 ms vs. 42 ± 24 ms, p = 0.0002).
Conclusions AS is associated with preserved atrial contractility and atrial synchrony, resulting in optimal LV diastolic filling, stroke volume, and LV systolic mechanics. This pacing mode maximizes LV performance and the hemodynamic benefit of CRT in patients with heart failure.
This work was supported in part by grant AG22554 from the National Institutes of Health. Dr. Abraham has received a research grant from GE Ultrasound. All other authors have reported that they have no relationships to disclose.
- Received January 14, 2011.
- Revision received February 16, 2011.
- Accepted February 24, 2011.
- American College of Cardiology Foundation