title: Validation of Left Atrial Volume Estimation by Left Atrial Diameter from the Parasternal Long-Axis View.
abstract: BACKGROUND
  Measurement of left atrial (LA) volume (LAV) is recommended for quantification of LA size. Only LA anteroposterior diameter (LAd) is available in a number of large cohorts, trials, or registries. The aim of this study was to evaluate whether LAV may be reasonably estimated from LAd.
  
  
  METHODS
  One hundred forty consecutive patients referred to our outpatient clinics were prospectively enrolled to measure LAd from the long-axis view on two-dimensional echocardiography. LA orthogonal dimensions were also taken from apical four- and two-chamber views. LAV was measured using the Simpson, area-length, and ellipsoid (LAVe) methods. The first 70 patients were the learning series and the last 70 the testing series (TeS). In the learning series, best-fitting regression analysis of LAV-LAd was run using all LAV methods, and the highest values of F were chosen among the regression equations. In the TeS, the best-fitting regressions were used to estimate LAV from LAd.
  
  
  RESULTS
  In the learning series, the best-fitting regression was linear for the Spearman method (r2= 0.62, F = 111.85, P = .0001) and area-length method (r2= 0.62, F = 112.24, P = .0001) and powered for the LAVemethod (r2= 0.81, F = 288.41, P = .0001). In the TeS, the r2value for LAV prediction was substantially better using the LAVemethod (r2= 0.89) than the Simpson (r2= 0.72) or area-length (r2= 0.70) method, as was the intraclass correlation (ρ = 0.96 vs ρ = 0.89 and ρ = 0.89, respectively). In the TeS, the sensitivity and specificity of LA dilatation by the estimated LAVemethod were 87% and 90%, respectively.
  
  
  CONCLUSIONS
  LAV can be estimated from LAd using a nonlinear equation with an elliptical model. The proposed method may be used in retrospective analysis of existing data sets in which determination of LAV was not programmed.
authors.affiliation: Hypertension Research Center, Federico II University Hospital, Naples, Italy.
authors.forename: Grazia
authors.initials: G
authors.lastname: Canciello
authors.affiliation: Hypertension Research Center, Federico II University Hospital, Naples, Italy. Electronic address: losi@unina.it.
authors.forename: Giovanni
authors.initials: G
authors.lastname: de Simone
authors.affiliation: Hypertension Research Center, Federico II University Hospital, Naples, Italy.
authors.forename: Raffaele
authors.initials: R
authors.lastname: Izzo
authors.affiliation: Hypertension Research Center, Federico II University Hospital, Naples, Italy; Department of Advanced Biomedical Sciences, Federico II University Hospital, Naples, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Giamundo
authors.affiliation: Hypertension Research Center, Federico II University Hospital, Naples, Italy; Department of Advanced Biomedical Sciences, Federico II University Hospital, Naples, Italy.
authors.forename: Filomena
authors.initials: F
authors.lastname: Pacelli
authors.affiliation: Hypertension Research Center, Federico II University Hospital, Naples, Italy.
authors.forename: Costantino
authors.initials: C
authors.lastname: Mancusi
authors.affiliation: Hypertension Research Center, Federico II University Hospital, Naples, Italy; Department of Advanced Biomedical Sciences, Federico II University Hospital, Naples, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Galderisi
authors.affiliation: Hypertension Research Center, Federico II University Hospital, Naples, Italy; Department of Advanced Biomedical Sciences, Federico II University Hospital, Naples, Italy.
authors.forename: Bruno
authors.initials: B
authors.lastname: Trimarco
authors.affiliation: Hypertension Research Center, Federico II University Hospital, Naples, Italy; Department of Advanced Biomedical Sciences, Federico II University Hospital, Naples, Italy.
authors.forename: Maria-Angela
authors.initials: MA
authors.lastname: Losi
mesh_terms: D000465:Algorithms; D004452:Echocardiography / Q000379:methods*; D005260:Female; D006325:Heart Atria / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D009929:Organ Size; D056888:Patient Positioning / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013249:Sternum / Q000000981:diagnostic imaging*
keywords: Echocardiography; Left atrial diameter; Left atrial size; Left atrial volume