title: Impact of acute biventricular pacing on left ventricular performance and volumes in patients with severe heart failure. A tissue doppler and three-dimensional echocardiographic study.
abstract: OBJECTIVE
  We used tissue velocity imaging (TVI) and three-dimensional echocardiography to evaluate the effect of acute biventricular pacing on left ventricular (LV) performance and volumes in patients with severe heart failure and bundle branch block.
  
  
  BACKGROUND
  Biventricular pacing causes acute hemodynamic improvement in patients with severe heart failure, and QRS duration has been used as a predictor of improved resynchronization. Tissue velocity has the potential of demonstrating the degree of LV resynchronization and three-dimensional echocardiography enables accurate quantitation of LV volumes and function.
  
  
  METHODS
  TVI and three-dimensional echocardiography were performed during sinus rhythm and biventricular pacing in 25 consecutive patients with severe heart failure.
  
  
  RESULTS
  Biventricular pacing significantly improved the extent of contracting myocardium in synchrony by 15.4% and the duration of contraction synchrony by 17% (p < 0.05 for both). Furthermore, end-diastolic and end-systolic volumes decreased by 7 +/- 4.5% and 13 +/- 6% (p < 0.01) and ejection fraction increased by 22.8 +/- 9% (p < 0.01). Baseline duration of QRS and the preejection period as well as the extent of myocardium with asynchronous contraction measured by TVI predicted pacing efficacy. In multivariate analysis, only the extent of myocardium with asynchronous contraction at the LV base predicted biventricular pacing efficacy.
  
  
  CONCLUSIONS
  Biventricular pacing improves LV systolic performance and reduces LV volumes during short-term treatment. TVI provides important pathophysiological information on the degree of LV resynchronization and may contribute to improved patient selection.
authors.affiliation: Department of Cardiology, Skejby Hospital, Aarhus University, Denmark. psogaard@dadlnet.dk
authors.forename: P
authors.initials: P
authors.lastname: Søgaard
authors.forename: W Y
authors.initials: WY
authors.lastname: Kim
authors.forename: H K
authors.initials: HK
authors.lastname: Jensen
authors.forename: P
authors.initials: P
authors.lastname: Mortensen
authors.forename: A K
authors.initials: AK
authors.lastname: Pedersen
authors.forename: B Ø
authors.initials: BØ
authors.lastname: Kristensen
authors.forename: H
authors.initials: H
authors.lastname: Egeblad
mesh_terms: D002037:Bundle-Branch Block / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D002303:Cardiac Output, Low / Q000000981:diagnostic imaging / Q000628:therapy*; D002304:Cardiac Pacing, Artificial / Q000379:methods; D018618:Echocardiography, Doppler, Color; D019560:Echocardiography, Three-Dimensional; D005260:Female; D006333:Heart Failure / Q000000981:diagnostic imaging / Q000628:therapy*; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D018487:Ventricular Dysfunction, Left / Q000628:therapy*