title: Normal left ventricular mechanical function and synchrony values by speckle-tracking echocardiography in the transplanted heart with normal ejection fraction.
abstract: BACKGROUND
  The purpose of this study was to describe the normal values for strain (S), systolic strain rate (SRs) and synchrony by speckle-tracking echocardiography (STE) in heart transplant (HTx) recipients who had normal left ventricular ejection fraction (LVEF) and no clinically significant complications.
  
  
  METHODS
  We evaluated S and SRs in 40 HTx patients at 1 year after transplant and 82 healthy controls with STE using velocity vector imaging.
  
  
  RESULTS
  Mean (SD) global longitudinal S and SRs, respectively, were lower in the transplant group compared with controls [-13.43% (2.39%) vs -17.28% (2.30%), p < 0.001; -0.83 (0.15) s(-1) vs -0.96 (0.13) s(-1), p < 0.001]. These variables were good for differentiating between groups: area under the curve was 0.88 for S and 0.73 for SRs. The differences remained significant after adjustment for other clinical variables. Global circumferential S and SRs were similar between groups. The standard deviation of the global longitudinal S time to peak of the 16 segments for HTx and control groups, respectively, was 41.67 (13.53) milliseconds vs 32.57 (12.81) milliseconds (p < 0.001). With 58.2 milliseconds as a cutoff value to define left ventricular synchrony, only 3 (8%) of the HTx patients and 4 (5%) of the control subjects were above that value (p = 0.6).
  
  
  CONCLUSIONS
  To our knowledge, this is the first study describing normal values for S and SRs and synchrony by STE in a HTx population with normal LVEF: longitudinal S and SRs were reduced; circumferential deformation indexes were normal; and left ventricular synchrony was preserved.
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota 55905, USA.
authors.forename: Haydar K
authors.initials: HK
authors.lastname: Saleh
authors.forename: Hector R
authors.initials: HR
authors.lastname: Villarraga
authors.forename: Garvan C
authors.initials: GC
authors.lastname: Kane
authors.forename: Naveen L
authors.initials: NL
authors.lastname: Pereira
authors.forename: Eugenia
authors.initials: E
authors.lastname: Raichlin
authors.forename: Yang
authors.initials: Y
authors.lastname: Yu
authors.forename: Yuki
authors.initials: Y
authors.lastname: Koshino
authors.forename: Sudhir S
authors.initials: SS
authors.lastname: Kushwaha
authors.forename: Fletcher A
authors.initials: FA
authors.lastname: Miller
authors.forename: Jae K
authors.initials: JK
authors.lastname: Oh
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Pellikka
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D015150:Echocardiography, Doppler / Q000379:methods; D005260:Female; D016027:Heart Transplantation / Q000000981:diagnostic imaging / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013318:Stroke Volume / Q000502:physiology*; D013599:Systole / Q000502:physiology; D016896:Treatment Outcome; D016277:Ventricular Function, Left / Q000502:physiology*