title: Right atrial indexed volume in healthy adult population: reference values for two-dimensional and three-dimensional echocardiographic measurements.
abstract: BACKGROUND
  Current guidelines do not recommend routine assessment of right atrial volume due to the lack of standardized data. Three-dimensional wall-motion tracking (3D-WMT) is a new technology that allows us to calculate volumes without any geometric assumptions. The aim of this study was to define the indexed reference values for two-dimensional echocardiography (2D-echo) and 3D-WMT in adult healthy population and to assess the intermethod, intra- and interobserver agreement.
  
  
  METHODS
  Prospective study. Nonselected healthy subjects were enrolled. Every patient underwent a 2D-echo and a 3D-WMT examination. 2D-echo right atrial volume was obtained by using the area-length method (A-L) from four- and two-chamber view. 3D-echo volumes were assessed by 3D-WMT. Values were indexed by the patient's body surface area.
  
  
  RESULTS
  Sixty consecutive healthy subjects were enrolled. Mean age was 57 ± 12-years old and 27 patients (45%) were male. Average indexed right atrial volume obtained by 2D-echo and 3D-echo was 16.76 ± 8.15 mL/m(2) and 19.05 ± 6.87 mL/m(2) , respectively. Univariate linear regression analysis between 2D-echo and 3D-echo right atrial volumes shows a weak correlation between right atrial volume obtained with 2D-echo compared with 3D-WMT (r = 0.29, CI 95% 0.029-0.66, P = 0.033). The agreement analysis shows a similar result (intraclass correlation coefficient [ICC] = 0.28). The intra- and interobserver agreement analysis showed a better agreement when using 3D-WMT.
  
  
  CONCLUSIONS
  This is the first study that reports the reference indexed right atrial volume values by means of 2D-echo and 3D-echo in healthy population. 3D-WMT is a feasible and reproducible method to determine right atrial volume.
authors: Cardiovascular Imaging Unit, Hospital Carlos III Madrid, Madrid, Spain.
authors: Joel
authors: J
authors: Moreno
authors: Leopoldo
authors: L
authors: Pérez de Isla
authors: Nellys
authors: N
authors: Campos
authors: Juan
authors: J
authors: Guinea
authors: Laura
authors: L
authors: Domínguez-Perez
authors: Adriana
authors: A
authors: Saltijeral
authors: Vera
authors: V
authors: Lennie
authors: Maribel
authors: M
authors: Quezada
authors: Alberto
authors: A
authors: de Agustín
authors: Pedro
authors: P
authors: Marcos-Alberca
authors: Patricia
authors: P
authors: Mahía
authors: Miguel Ángel
authors: MÁ
authors: García-Fernández
authors: Carlos
authors: C
authors: Macaya
mesh_terms: D016275:Atrial Function / Q000502:physiology*; D019560:Echocardiography, Three-Dimensional / Q000592:standards* / Q000706:statistics & numerical data*; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D009929:Organ Size / Q000502:physiology*; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013030:Spain / Q000453:epidemiology
keywords: reference values; right atrium; three-dimensional echocardiography; three-dimensional-wall motion tracking