title: A novel method for indexing echocardiographic left ventricular mass in infants, children and adolescents: evaluation of obesity-induced left ventricular hypertrophy.
abstract: BACKGROUND
  Measurement of left ventricular mass (LVM) is important to the diagnosis of left ventricular hypertrophy in children with various cardiovascular diseases. The purpose of this study was to determine the most appropriate method for standardization of LVM and to evaluate obesity-induced left ventricular hypertrophy in children across the entire age range, from infancy through adolescence.
  
  
  METHODS
  We studied 928 children and adolescents (527 males, 401 females), aged 0-17 years, who were classified into two groups by degree of obesity. Left ventricular mass was calculated by M-mode echocardiography using the formula of Devereux et al. and was indexed using body size (body length, bodyweight or body surface area) raised to a non-integer power using logarithmic transformation of measurements in children without obesity.
  
  
  RESULTS
  The body length, bodyweight and body surface area exponents were 1.85, 0.88 and 1.15, respectively, in males, and 1.72, 0.82 and 1.08, respectively, in females. Whereas indexing of left ventricular mass by body length both in males and in females revealed significant differences between the two groups, indexing using bodyweight or body surface area exponents did not manifest left ventricular hypertrophy induced by obesity.
  
  
  CONCLUSIONS
  It is suggested that applying body length exponents 1.85 in males and 1.72 in females is an appropriate method for indexation of LVM in children and adolescents. This method is particularly useful for the evaluation of left ventricular hypertrophy in children.
authors.affiliation: Department of Pediatrics, Toyama Medical Pharmaceutical University, Japan.
authors.forename: I
authors.initials: I
authors.lastname: Hashimoto
authors.forename: F
authors.initials: F
authors.lastname: Ichida
authors.forename: S
authors.initials: S
authors.lastname: Tsubata
authors.forename: Y
authors.initials: Y
authors.lastname: Hamamichi
authors.forename: K
authors.initials: K
authors.lastname: Uese
authors.forename: A
authors.initials: A
authors.lastname: Miyazaki
authors.forename: T
authors.initials: T
authors.lastname: Miyawaki
mesh_terms: D000293:Adolescent; D001824:Body Constitution; D001835:Body Weight; D002648:Child; D002675:Child, Preschool; D004452:Echocardiography / Q000706:statistics & numerical data*; D005260:Female; D006352:Heart Ventricles / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000000981:diagnostic imaging* / Q000209:etiology; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009765:Obesity / Q000150:complications*; D012016:Reference Values