title: Age- and gender-dependency of left ventricular geometry assessed with real-time three-dimensional transthoracic echocardiography.
abstract: BACKGROUND
  Aging and gender may affect left ventricular (LV) mechanics. The aim of this study was to determine the age and gender dependency of LV mechanical indices obtained from real-time three-dimensional echocardiography (RT3DE).
  
  
  METHODS
  RT3DE was performed in 280 healthy subjects (age range, 1-88 years; 137 men). From full-volume data sets, LV endocardial and epicardial borders were semiautomatically traced using quantitative software. LV volumes and corresponding long-axis diameter were measured throughout the cardiac cycle. Sphericity index was defined as the ratio of LV volume and spherical volume, calculated as 4/3 × π × (long-axis diameter/2)(3). LV mass was calculated as (LV epicardial volume - LV endocardial volume) × 1.05. The ratio of LV mass to LV volume was also calculated.
  
  
  RESULTS
  The mean value of LV ejection fraction did not change with age. However, LV volumes, mass, sphericity index, and LV mass/volume ratio were altered by age: (1) sphericity index was highest in the first decade of age and then declined until the fifth decade, (2) LV mass/volume ratio significantly increased in older age, and (3) LV mass/volume ratio was significantly higher in aged women compared with age-matched men.
  
  
  CONCLUSIONS
  Age has heterogeneous effects on LV shape and LV mass/volume ratio, potentially due to the growing process of myocardial fibers and the surrounding architecture in the younger population, as well as the aging process, with an increase in vascular stiffness and a loss of myocytes in older populations. Higher LV mass/volume ratios in older women might be a contributor to the preferential development of diastolic heart failure in this population.
authors.affiliation: University of Occupational and Environmental Health, School of Medicine, Kitakyushu, Japan.
authors.forename: Kyoko
authors.initials: K
authors.lastname: Kaku
authors.forename: Masaaki
authors.initials: M
authors.lastname: Takeuchi
authors.forename: Kyoko
authors.initials: K
authors.lastname: Otani
authors.forename: Lissa
authors.initials: L
authors.lastname: Sugeng
authors.forename: Hiromi
authors.initials: H
authors.lastname: Nakai
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Haruki
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Yoshitani
authors.forename: Nozomi
authors.initials: N
authors.lastname: Watanabe
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Yoshida
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Otsuji
authors.forename: Victor
authors.initials: V
authors.lastname: Mor-Avi
authors.forename: Roberto M
authors.initials: RM
authors.lastname: Lang
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D003199:Computer Systems; D019560:Echocardiography, Three-Dimensional / Q000295:instrumentation*; D005260:Female; D006352:Heart Ventricles / Q000033:anatomy & histology / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D013318:Stroke Volume; D016277:Ventricular Function, Left; D055815:Young Adult