title: Repeatability and reproducibility of measurements obtained via two-dimensional speckle tracking echocardiography of the left atrium and time-left atrial area curve analysis in healthy dogs.
abstract: OBJECTIVE
  To evaluate left atrial phasic function in healthy dogs by means of 2-D speckle tracking echocardiography with time-left atrial area curve analysis and to assess repeatability and reproducibility of obtained measurements.
  
  
  METHODS
  6 healthy Beagles.
  
  
  METHODS
  Each dog underwent echocardiography twice on different days (3 nonconsecutive examinations/d). Images were analyzed with offline software; area of the left atrium was automatically calculated in each frame throughout the cardiac cycle to derive time-left atrial area curves. Variables used to assess left atrial phasic function (total, passive, and active emptying area and emptying fractions and mean active and total emptying rates) were calculated. Agreement between variables measured via speckle tracking echocardiography and a manual tracing method was assessed with modified Bland-Altman analysis. Within-day and between-day coefficients of variation were determined.
  
  
  RESULTS
  Mean ± SD total, passive, and active emptying fractions of the left atrium were 49.8 ± 3.5%, 277 ± 4.0%, and 30.5 ± 4.3%, respectively. Mean ± SD total and active emptying rates were 16.0 ± 2.5 cm(2)/s and 25.1 ± 4.9 cm(2)/s, respectively. Within-day and between-day coefficients of variation were < 20% (range, 0.41% to 16.4%) for all variables except mean active emptying rate (between-day coefficient of variation, 29.2%). Agreement between variables measured via speckle tracking echocardiography and the manual tracing method was good, and differences between methods were nonsignificant.
  
  
  CONCLUSIONS
  Evaluation of left atrial phasic function via speckle tracking echocardiography was feasible; repeatability and reproducibility of measurements were adequate in healthy dogs. Studies are needed to determine clinical applicability in canine patients.
authors.affiliation: Laboratory of Veterinary Internal Medicine, Department of Veterinary Clinical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan.
authors.forename: Tatsuyuki
authors.initials: T
authors.lastname: Osuga
authors.forename: Kensuke
authors.initials: K
authors.lastname: Nakamura
authors.forename: Sue Yee
authors.initials: SY
authors.lastname: Lim
authors.forename: Yu
authors.initials: Y
authors.lastname: Tamura
authors.forename: Wickramasekara Rajapakshage Bandula
authors.initials: WR
authors.lastname: Kumara
authors.forename: Masahiro
authors.initials: M
authors.lastname: Murakami
authors.forename: Noboru
authors.initials: N
authors.lastname: Sasaki
authors.forename: Keitaro
authors.initials: K
authors.lastname: Morishita
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ohta
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yamasaki
authors.forename: Mitsuyoshi
authors.initials: M
authors.lastname: Takiguchi
mesh_terms: D000818:Animals; D016279:Atrial Function, Left / Q000502:physiology*; D004285:Dogs / Q000033:anatomy & histology* / Q000502:physiology*; D004452:Echocardiography / Q000379:methods / Q000662:veterinary*; D005260:Female; D006325:Heart Atria / Q000033:anatomy & histology*; D008297:Male; D015203:Reproducibility of Results