title: Prevalence and inter-relationship of different Doppler measures of dyssynchrony in patients with heart failure and prolonged QRS: a report from CARE-HF.
abstract: BACKGROUND
  Cardiac resynchronisation therapy (CRT) improves mortality and morbidity in heart failure patients with wide QRS. Observational studies suggest that patients having more left ventricular dyssynchrony pre-implantation obtain greater benefit on ventricular function and symptoms with CRT.
  
  
  OBJECTIVE
  To provide an analysis of the prevalence and type of dyssynchrony in patients included in the CARE-HF trial.
  
  
  METHODS
  100 patients 67 (58 to 71) years were examined with echocardiography including tissue doppler imaging before receiving a CRT-pacemaker. Atrio-ventricular dyssynchrony (LVFT/RR) was defined as left ventricular filling time <40% of the RR-interval. Inter-ventricular mechanical delay (IVMD) was measured as the difference in onset of Doppler-flow in the pulmonary and aortic outflow tracts >40 ms. Intra-ventricular (regional) dyssynchrony in a 16-segment model was expressed either as a delayed longitudinal contraction (DLC) during the postsystolic phase or by tissue synchronisation imaging (TSI) with a predefined time-difference in systolic maximal velocities >85 ms.
  
  
  RESULTS
  LVFT/RR was present in 34% and IVMD in 60% of patients while intra-ventricular dyssynchrony was present in 85% (DLC) and 86% (TSI) with a high agreement between the measures (Kappascore 0.86-1.00), indicating the methods being interchangeable. Patients with cardiomyopathy (53%) were more likely to have LVFT/RR <40% (45% vs. 21% (p= 0.02)) and more segments affected by intra-ventricular dyssynchrony 4(3, 5) vs. 3(1, 4), p = 0.002, compared to patients with ischemic heart disease.
  
  
  CONCLUSIONS
  The prevalence of intra-ventricular dyssynchrony is high in patients with heart failure, wide QRS and depressed systolic function. Most important, TSI appears to be a fast and reliable method to identify patients with intra-ventricular dyssynchrony likely to benefit from CRT.
authors.affiliation: Karolinska Institutet, Department of Clinical Sciences, Danderyd Hospital, Stockholm, Sweden. magnus.edner@ds.se
authors.forename: Magnus
authors.initials: M
authors.lastname: Edner
authors.forename: Yong
authors.initials: Y
authors.lastname: Kim
authors.forename: Knud Norregaard
authors.initials: KN
authors.lastname: Hansen
authors.forename: Henrik
authors.initials: H
authors.lastname: Nissen
authors.forename: Geert
authors.initials: G
authors.lastname: Espersen
authors.forename: Karl
authors.initials: K
authors.lastname: La Rosee
authors.forename: Fikru
authors.initials: F
authors.lastname: Maru
authors.forename: Nick
authors.initials: N
authors.lastname: Freemantle
authors.forename: John
authors.initials: J
authors.lastname: Cleland
authors.forename: Peter
authors.initials: P
authors.lastname: Sogaard
mesh_terms: D000368:Aged; D015897:Comorbidity; D004452:Echocardiography / Q000379:methods* / Q000706:statistics & numerical data*; D005260:Female; D006333:Heart Failure / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009518:New York / Q000453:epidemiology; D015995:Prevalence; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000453:epidemiology*