title: Three-Dimensional Rotation, Twist and Torsion Analyses Using Real-Time 3D Speckle Tracking Imaging: Feasibility, Reproducibility, and Normal Ranges in Pediatric Population.
abstract: OBJECTIVE
  The specific aim of this study was to evaluate the feasibility, reproducibility and maturational changes of LV rotation, twist and torsion variables by real-time 3D speckle-tracking echocardiography (RT3DSTE) in children.
  
  
  METHODS
  A prospective study was conducted in 347 consecutive healthy subjects (181 males/156 females, mean age 7.12 ± 5.3 years, and range from birth to 18-years) using RT 3D echocardiography (3DE). The LV rotation, twist and torsion measurements were made off-line using TomTec software. Manual landmark selection and endocardial border editing were performed in 3 planes (apical "2"-, "4"-, and "3"- chamber views) and semi-automated tracking yielded LV rotation, twist and torsion measurements. LV rotation, twist and torsion analysis by RT 3DSTE were feasible in 307 out of 347 subjects (88.5%).
  
  
  RESULTS
  There was no correlation between rotation or twist and age, height, weight, BSA or heart rate, respectively. However, there was statistically significant, but very modest correlation between LV torsion and age (R2 = 0.036, P< 0.001). The normal ranges were defined for rotation and twist in this cohort, and for torsion for each age group. The intra-observer and inter-observer variabilities for apical and basal rotation, twist and torsion ranged from 7.3% ± 3.8% to 12.3% ± 8.8% and from 8.8% ± 4.6% to 15.7% ± 10.1%, respectively.
  
  
  CONCLUSIONS
  We conclude that analysis of LV rotation, twist and torsion by this new RT3D STE is feasible and reproducible in pediatric population. There is no maturational change in rotation and twist, but torsion decreases with age in this cohort. Further refinement is warranted to validate the utility of this new methodology in more sensitive and quantitative evaluation of congenital and acquired heart diseases in children.
authors.affiliation: Department of Ultrasound, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.|The Heart Center, St. Christopher's Hospital for Children/Drexel University College of Medicine, Philadelphia, PA, United States of America.
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Ultrasound, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Ultrasound, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Han
authors.affiliation: Department of Ultrasound, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.|Department of Ultrasound, Wuhan Women and Children Medical Center, Wuhan, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Gao
authors.affiliation: Department of Ultrasound, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Lin
authors.initials: L
authors.lastname: He
authors.affiliation: Department of Ultrasound, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Yali
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Epidemiology and Health Statistics, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Yin
authors.affiliation: Department of Ultrasound, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Mingxing
authors.initials: M
authors.lastname: Xie
authors.affiliation: The Heart Center, St. Christopher's Hospital for Children/Drexel University College of Medicine, Philadelphia, PA, United States of America.|Deborah Heart and Lung Center, Browns Mills, NJ 08015, United States of America.
authors.forename: Shuping
authors.initials: S
authors.lastname: Ge
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D007223:Infant; D008297:Male; D015588:Observer Variation; D011446:Prospective Studies; D015203:Reproducibility of Results