title: Myocardial Rotation and Torsion in Child Growth.
abstract: BACKGROUND
  The speckle tracking echocardiography can benefit to assess the regional myocardial deformations. Although, previous reports suggested no significant change in left ventricular (LV) torsion with aging, there are certain differences in LV rotation at the base and apex. The purpose of this study was to evaluate the change and relationship of LV rotation for torsion with aging in children.
  
  
  METHODS
  Forty healthy children were recruited and divided into two groups of twenty based on whether the children were preschool-age (2-6 years of age) or school-age (7-12 years of age). After obtaining conventional echocardiographic data, apical and basal short axis rotation were assessed with speckle tracking echocardiography. LV rotation in the basal and apical short axis planes was determined using six myocardial segments along the central axis.
  
  
  RESULTS
  Apical and basal LV rotation did not show the statistical difference with increased age between preschool- and school-age children. Apical radial strain showed significant higher values in preschool-age children, especially at the anterior (52.8 ± 17.4% vs. 34.7 ± 23.2%,p< 0.02), lateral (55.8 ± 20.4% vs. 36.1 ± 22.7%,p< 0.02), and posterior segments (57.1 ± 17.6% vs. 38.5 ± 21.7%,p< 0.01). The torsion values did not demonstrate the statistical difference between two groups.
  
  
  CONCLUSIONS
  This study revealed the tendency of higher rotation values in preschool-age children than in school-age children. The lesser values of rotation and torsion with increased age during childhood warrant further investigation.
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Chang Sin
authors.initials: CS
authors.lastname: Kim
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sora
authors.initials: S
authors.lastname: Park
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Lucy Youngmin
authors.initials: LY
authors.lastname: Eun
keywords: Age difference; Children; Left ventricular rotation; Left ventricular torsion