title: Quantification of myocardial deformation in children by cardiovascular magnetic resonance feature tracking: determination of reference values for left ventricular strain and strain rate.
abstract: BACKGROUND
  The objective assessment of global and regional cardiac function in children has shown to be clinically relevant but is challenging to conduct. Cardiovascular magnetic resonance (CMR) has emerged as a valuable diagnostic modality especially in patients with cardiomyopathy or congenital heart disease. However, data on the normal cardiac deformation in children assessed by CMR is lacking at present. Thus, the aim of this study was to provide reference values for cardiac strain and strain rate in children and adolescents derived from CMR feature tracking (FT) measurements.
  
  
  METHODS
  In this binational study, eighty children and adolescents (age 0.4-18.0 years, 41 male, 39 female) free from cardiac diseases from two centers underwent CMR in 1.5 T whole-body scanners in supine position. Global peak radial, circumferential and longitudinal systolic strains as well as the corresponding early peak diastolic strain rates were assessed applying FT on short axis as well as 3- and 4-chamber views of standard cine steady-state free precession images.
  
  
  RESULTS
  The difference between genders yielded no significance for all assessed strains. Yet, all strains showed a significant parabolic relation to age and an even stronger one to body surface area (BSA). Therefore, BSA-specific reference values were determined using a polynomial regression model. The apical cardiac segments featured significant higher peak circumferential but lower peak radial systolic strains than the midventricular and basal segments (all p < 0.001).
  
  
  CONCLUSIONS
  The assessment of cardiac deformation by CMR-FT is feasible in children. This is the first CMR study providing specific reference values for FT-derived strain and strain rate in the pediatric age range.
authors.affiliation: Department of Cardiology, Angiology and Pneumology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: André
authors.affiliation: Department of Pediatrics, Division of Pediatric Cardiology and Department of Radiology, Erasmus MC-Sophia Children's Hospital, Rotterdam, The Netherlands.
authors.forename: Daniëlle
authors.initials: D
authors.lastname: Robbers-Visser
authors.affiliation: Department of General Pediatrics, University of Heidelberg, Heidelberg, Germany.
authors.forename: Astrid
authors.initials: A
authors.lastname: Helling-Bakki
authors.affiliation: Department of General Pediatrics, University of Heidelberg, Heidelberg, Germany.
authors.forename: Angela
authors.initials: A
authors.lastname: Föll
authors.affiliation: Institute of Psychology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Voss
authors.affiliation: Department of Cardiology, Angiology and Pneumology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Hugo A
authors.initials: HA
authors.lastname: Katus
authors.affiliation: Department of Pediatrics, Division of Pediatric Cardiology and Department of Radiology, Erasmus MC-Sophia Children's Hospital, Rotterdam, The Netherlands.
authors.forename: Willem A
authors.initials: WA
authors.lastname: Helbing
authors.affiliation: Department of Cardiology, Angiology and Pneumology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Sebastian J
authors.initials: SJ
authors.lastname: Buss
authors.affiliation: Klinikum Leverkusen, Children's Hospital, Am Gesundheitspark 11, 51375, Leverkusen, Germany. joachim.eichhorn@klinikum-lev.de.
authors.forename: Joachim G
authors.initials: JG
authors.lastname: Eichhorn
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001696:Biomechanical Phenomena; D002648:Child; D002675:Child, Preschool; D005260:Female; D005858:Germany; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D007223:Infant; D019028:Magnetic Resonance Imaging, Cine / Q000592:standards*; D008297:Male; D009200:Myocardial Contraction; D009426:Netherlands; D015588:Observer Variation; D056888:Patient Positioning; D011237:Predictive Value of Tests; D012015:Reference Standards; D015203:Reproducibility of Results; D013314:Stress, Mechanical; D016683:Supine Position; D016277:Ventricular Function, Left; D051598:Whole Body Imaging
keywords: Cardiovascular magnetic resonance; Feature tracking; Pediatrics; Physiology; Reference values; Strain