title: Intra-left ventricular electromechanical asynchrony. A new independent predictor of severe cardiac events in heart failure patients.
abstract: OBJECTIVE
  We sought to assess the electromechanical parameters, using tissue Doppler echocardiography, as potential independent predictors of heart failure (HF) worsening.
  
  
  BACKGROUND
  Ventricular conduction disorders worsen the prognosis for HF patients. However, the relationships between the QRS width and morphology, hemodynamic parameters, and presence and magnitude of intra-left ventricular (LV) and inter-ventricular (V) asynchrony have not been well clarified.
  
  
  METHODS
  A total of 104 patients with an LV ejection fraction (EF) </=45% and stabilized HF, without myocardial infarction (MI), underwent echocardiography coupled with tissue Doppler imaging and were followed for one year. The protocol analyzed the incidence of worsening HF (hospitalization for cardiac decompensation). Inter-V and regional electromechanical delays for the anterior, septal, inferior, and lateral LV walls were correlated with the QRS morphology and duration. The intra-LV and inter-V asynchrony values of these patients were compared with those of healthy subjects matched by gender and age criteria to determine the respective normal ranges.
  
  
  RESULTS
  The presence of intra-LV (but not inter-V) asynchrony was identified as an independent predictor of severe cardiac events (hazard ratio 3.39, p < 0.0001), independent of the LVEF and QRS width. Of patients with a QRS width <120 ms (55%; n = 57), 56% presented with major intra-LV asynchrony and 12% with inter-V asynchrony. Intra-LV asynchrony was observed in 84% of left bundle branch block patients, but also in 83% of right bundle branch block patients (p = NS). There was a poor correlation between the QRS width and intra-LV or inter-V asynchrony (r = 0.36, p = NS and r = 0.43, p = 0.05, respectively).
  
  
  CONCLUSIONS
  In HF patients without MI, patients with intra-LV asynchrony are those with a significantly higher risk of cardiac events, independent of the QRS width and LVEF. Accordingly, such patients should be more actively identified for early intensive treatment and survey.
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, University of Bordeaux, Pessac, France.
authors.forename: Hugues
authors.initials: H
authors.lastname: Bader
authors.forename: Stephane
authors.initials: S
authors.lastname: Garrigue
authors.forename: Stephane
authors.initials: S
authors.lastname: Lafitte
authors.forename: Sylvain
authors.initials: S
authors.lastname: Reuter
authors.forename: Pierre
authors.initials: P
authors.lastname: Jaïs
authors.forename: Michel
authors.initials: M
authors.lastname: Haïssaguerre
authors.forename: Jacques
authors.initials: J
authors.lastname: Bonnet
authors.forename: Jacques
authors.initials: J
authors.lastname: Clementy
authors.forename: Raymond
authors.initials: R
authors.lastname: Roudaut
mesh_terms: D000368:Aged; D003324:Coronary Artery Disease / Q000503:physiopathology; D015150:Echocardiography, Doppler / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology; D006333:Heart Failure / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology; D011237:Predictive Value of Tests; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000503:physiopathology