title: Reference Values for Real Time Three-Dimensional Echocardiography-Derived Left Ventricular Volumes and Ejection Fraction: Review and Meta-Analysis of Currently Available Studies.
abstract: BACKGROUND
  Current guidelines recommend three-dimensional echocardiography (3DE) as the reference technique to assess left ventricular (LV) volumes and ejection fraction (EF). We performed a meta-analysis to identify normative reference values by real time 3DE in healthy subjects.
  
  
  METHODS
  We searched MEDLINE and the Cochrane Library databases using the key search terms three-dimensional echocardiography, volumes, and healthy. Data were pooled using random-effects meta-analysis, and source of variation was investigated using meta-regression. After selection, 13 articles were included (2806 subjects). Four studies were conducted in children and young adolescents; one study provided data in an independent pediatric subgroup.
  
  
  RESULTS
  In adults, pooled mean value for LV EDV was 98.4 mL (95%CI, 87-110 mL), while LV ESV mean value was 37.0 mL (95%CI, 32-42 mL). LV EF mean value was 62.9% (95%CI 61.7-64.2%). Male subjects showed a significant increase in both LV EDV index (mean difference 5.3 mL/m(2) ; P < 0.001) and LV ESV index (mean difference 3.3 mL/m(2) ; P < 0.001). LV EF was significantly higher in female subjects (P = 0.003). In pediatric studies, LV EDV pooled mean value was 53.1 mL (95%CI, 38.1-68 mL), while for LV ESV, it was 19.8 mL (95%CI, 14.8-24.8 mL); LV EF mean value was 63.3% (95%CI, 61.6-65%). Significant heterogeneity and inconsistency were noted among studies. Age, systolic blood pressure, and heart rate were identified as a source of between-studies variation for LV volumes. Body surface area was a predictor of nonindexed LV volumes.
  
  
  CONCLUSIONS
  Data from available studies of normative values for 3DE were summarized. Our findings may increase the generalizability of LV normative data by 3DE.
authors.affiliation: Medical and Pediatric Sciences Department, University of Catania, Catania, Italy.
authors.forename: Sergio
authors.initials: S
authors.lastname: Buccheri
authors.affiliation: Medical and Pediatric Sciences Department, University of Catania, Catania, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Costanzo
authors.affiliation: Medical and Pediatric Sciences Department, University of Catania, Catania, Italy.
authors.forename: Corrado
authors.initials: C
authors.lastname: Tamburino
authors.affiliation: Medical and Pediatric Sciences Department, University of Catania, Catania, Italy.
authors.forename: Ines
authors.initials: I
authors.lastname: Monte
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D049628:Body Size / Q000502:physiology; D003199:Computer Systems; D019560:Echocardiography, Three-Dimensional / Q000592:standards* / Q000706:statistics & numerical data*; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000592:standards; D008297:Male; D008875:Middle Aged; D017410:Practice Guidelines as Topic; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012737:Sex Factors; D013318:Stroke Volume / Q000502:physiology*; D016277:Ventricular Function, Left / Q000502:physiology*; D055815:Young Adult
keywords: left ventricular volumes; three-dimensional echocardiography