CRT
Left ventricular electromechanical delay in patients with heart failure and normal QRS duration and in patients with right and left bundle branch block
1 Cardiology Unit, Echo-lab, Department of Cardiopulmonary Sciences, A.O. Santa Maria della Misericordia, P.le S Maria della Misericordia 15, 33100 Udine, Italy; 2 Department of Cardiology, Ospedale S. Maria Nuova, Reggio Emilia, Italy; 3 Department of Cardiology, Ospedale S Giovanni Calibita Fatebenefratelli, Rome, Italy; 4 Department of Cardiology, Ospedali del Tigullio, Lavagna, Italy; 5 Department of Cardiology, Hospital Clinic, Barcelona, Spain; 6 Department of Cardiology, Heraklion University Hospital of Crete, Greece; 7 St Anna Hospital, Como, Italy; 8 Department of Cardiology, Ospedale di Bentivoglio, Italy; 9 Department of Cardiology, Ospedale S Anna, Como, Italy; 10 Department of Cardiology, Ospedale S Giuseppe Moscati, Avellino Italy; 11 Medtronic Italia S.p.A. Italy
Aims We sought to define the reference values of intra-left ventricular (LV) electromechanical delay (EMD), and to assess the prevalence (and pattern) of intra-LV dyssynchrony in patients with heart failure (HF) and normal QRS and in patients with right and left bundle branch block.
Methods and results We used tissue Doppler imaging echocardiography and a six-LV wall model to study LV EMD in 103 patients [41 with HF and normal QRS, 22 with right bundle branch block (RBBB), and 40 with left bundle branch block (LBBB)], and in 59 controls. In controls, the median intra-LV EMD was 17 ms, (inter-quartile range 13–30); 95% of controls had a value 
41 ms. Patients showed a longer intra-LV EMD than controls: 33 ms (20–57) in patients with normal QRS, 32 ms (23–50) in RBBB patients, and 50 ms (30–94) in LBBB patients. Intra-LV dyssynchrony (defined as intra-LV EMD >41 ms) was present in 39, 36, and 60% of the patients, respectively. On average, HF patients showed the same pattern of activation as controls, from the septum to the posterior wall, but activation times were significantly prolonged. In RBBB patients the activation sequence was directed from inferior to anterior and in LBBB from anterior to inferior wall.
Conclusions Left ventricular dyssynchrony was present in several patients with HF and normal QRS, and in patients with RBBB; conversely, 40% of LBBB patients showed values of LV EMD within the normal range. Left ventricular activation sequence was different between groups. Assessment of LV synchronicity by means of imaging techniques may be more important than QRS duration or morphology in selecting patients for cardiac resynchronization treatment.
Key Words: Bundle branch block, Heart failure, Echocardiography, Electromechanical synchronicity, Left ventricular dyssynchrony, Tissue Doppler imaging
* Corresponding author. Tel: +39 0432 552444; fax: +39 0432 482353. E-mail address: lbadan{at}tin.it
CiteULike 
Connotea 
Del.icio.us What's this?
Related articles in Europace:
- Left ventricular electromechanical delay in patients with heart failure and normal QRS duration and in patients with right and left bundle branch block
- Luigi P. Badano, Oscar Gaddi, Carlo Peraldo, Gabriele Lupi, Marta Sitges, Frangisko Parthenakis, Santo Molteni, Maria Rosaria Pagliuca, Biagio Sassone, Paola Di Stefano, Tiziana De Santo, Carlo Menozzi, and Michele Brignole
Europace 2007 10.1093/europace/eum030.[Full Text]
This article has been cited by other articles:
|
|
 |
|
  M. Haghjoo, A. Bagherzadeh, M. M. Farahani, Z. O. Haghighi, and M. A. Sadr-Ameli Significance of QRS morphology in determining the prevalence of mechanical dyssynchrony in heart failure patients eligible for cardiac resynchronization: particular focus on patients with right bundle branch block with and without coexistent left-sided conduction defects Europace, May 1, 2008; 10(5): 566 - 571. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Brignole, D. Oddone, R. Maggi, G. Lupi, R. Bollini, S. Corallo, S. Robotti, A. Solano, P. Donateo, and F. Croci Resynchronization of the left ventricular contraction by tailored programming of right and left ventricular pacing Europace, April 1, 2008; 10(4): 489 - 495. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. de Teresa, J. J. Gomez-Doblas, G. Lamas, J. Alzueta, I. Fernandez-Lozano, E. Cobo, X. Navarro, F. Navarro-Lopez, and M. Stockburger Preventing ventricular dysfunction in pacemaker patients without advanced heart failure: rationale and design of the PREVENT-HF study Europace, June 1, 2007; 9(6): 442 - 446. [Abstract] [Full Text] [PDF]
|
|