title: Quantification of regional left and right ventricular radial and longitudinal function in healthy children using ultrasound-based strain rate and strain imaging.
abstract: BACKGROUND
  Noninvasive assessment of left (LV) and right (RV) ventricular function in children could benefit from a technique that would characterize local myocardial deformation. Color Doppler myocardial imaging (CDMI) allows the calculation of either local longitudinal or radial Strain Rate (SR) and Strain (epsilon). To determine the clinical feasibility and reproducibility of longitudinal and radial SR and epsilon, the following study was carried out.
  
  
  METHODS
  CDMI data were obtained from 33 healthy children (4-16 years). To quantify regional longitudinal and radial function SR and epsilon data were obtained from apical and parasternal views respectively. From the extracted SR curves, peak values for systole, early diastole, and late diastole were calculated. From the extracted epsilon curves the systolic, early and late diastolic epsilon values were calculated.
  
  
  RESULTS
  LV longitudinal deformation were homogeneous for LV basal, mid and apical segments (peak systolic SR: -1.9 +/- 0.7 s(-1), systolic epsilon -25% +/- 7%). Longitudinal SR and epsilon values were significantly higher and heterogeneous in the RV (compared with LV walls) and were maximal in the mid part of the RV free wall (peak systolic SR: -2.8 +/- 0.7 s(-1), systolic epsilon -45% +/- 13%). The RV inferior wall showed homogeneous but lower longitudinal SR and epsilon values. The LV systolic and diastolic SR and epsilon values were higher for deformation in the radial direction compared with the longitudinal direction (radial peak systolic SR: 3.7 +/- 0.9 s(-1), radial systolic epsilon 57% +/- 11%; P <.0001). The interobserver variability for radial systolic epsilon and SR was 10.3% and 13.1%, respectively.
  
  
  CONCLUSIONS
  Ultrasound-based Strain SR/epsilon imaging is a practical, reproducible clinical technique, which allows the calculation of regional longitudinal and radial deformation from both LV and RV segments. The combination of regional SR/epsilon indices and the timing of specific systolic or diastolic regional events may offer a new noninvasive approach to quantifying regional myocardial function in congenital and acquired heart disease in children.
authors.affiliation: Department of Cardiology, University Hospital Gasthuisberg, Leuven, Belgium.
authors.forename: Frank
authors.initials: F
authors.lastname: Weidemann
authors.forename: Benedicte
authors.initials: B
authors.lastname: Eyskens
authors.forename: Fadi
authors.initials: F
authors.lastname: Jamal
authors.forename: Luc
authors.initials: L
authors.lastname: Mertens
authors.forename: Miroslaw
authors.initials: M
authors.lastname: Kowalski
authors.forename: Jan
authors.initials: J
authors.lastname: D'Hooge
authors.forename: Bart
authors.initials: B
authors.lastname: Bijnens
authors.forename: Marc
authors.initials: M
authors.lastname: Gewillig
authors.forename: Frank
authors.initials: F
authors.lastname: Rademakers
authors.forename: Liv
authors.initials: L
authors.lastname: Hatle
authors.forename: George R
authors.initials: GR
authors.lastname: Sutherland
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002669:Child Welfare; D002675:Child, Preschool; D003971:Diastole / Q000502:physiology; D004452:Echocardiography; D006339:Heart Rate / Q000502:physiology; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D015588:Observer Variation; D012016:Reference Values; D015203:Reproducibility of Results; D013599:Systole / Q000502:physiology; D018615:Ultrasonography, Doppler, Color; D016276:Ventricular Function; D016277:Ventricular Function, Left / Q000502:physiology*; D016278:Ventricular Function, Right / Q000502:physiology*