title: Assessment of left ventricular global and regional longitudinal peak systolic strain, strain rate and velocity with feature tracking in healthy fetuses.
abstract: OBJECTIVE
  The aim of this study was to evaluate the correlation of feature-tracking-derived measurements of the left ventricular myocardium in healthy fetuses with gestational age.
  
  
  METHODS
  The global and segmental longitudinal peak systolic strain, strain rate and velocity values of the left ventricular myocardium for each gestational age were assessed by a novel feature tracking technique in 150 healthy fetuses (gestational age range 13 - 39 weeks of gestation). The interobserver and intraobserver variability was analyzed.
  
  
  RESULTS
  The global longitudinal peak systolic velocity exhibited a segmental base to apex gradient (p < 0.001). From 13 to 39 weeks of gestation, the global and segmental longitudinal peak systolic velocities increased significantly throughout gestation (p < 0.001), while the global longitudinal peak systolic strain remained constant (p = 0.34) and the strain rate exhibited only a tendency to decrease (p = 0.045). The interobserver and intraobserver variability of the global LV peak systolic strain, strain rate and velocity was acceptable. The standard deviations of measurement error between the two observers were 2.5 %, 0.7 s (-1) and 0.5 cm/sec, respectively.
  
  
  CONCLUSIONS
  The global myocardial peak systolic velocities of the left ventricle increase with gestational age, while the global myocardial peak systolic strain and strain rate remained nearly constant throughout gestation. This novel angle-independent, noninvasive technique offers a new objective approach to quantify global and segmental fetal myocardial performance throughout gestation.
authors.affiliation: Department of Obstetrics and Prenatal Medicine, University of Bonn, Germany.
authors.forename: A M
authors.initials: AM
authors.lastname: Willruth
authors.forename: A
authors.initials: A
authors.lastname: Geipel
authors.forename: C
authors.initials: C
authors.lastname: Berg
authors.forename: R
authors.initials: R
authors.lastname: Fimmers
authors.forename: U
authors.initials: U
authors.lastname: Gembruch
mesh_terms: D001783:Blood Flow Velocity / Q000502:physiology*; D015150:Echocardiography, Doppler / Q000379:methods*; D005260:Female; D005318:Fetal Heart / Q000000981:diagnostic imaging*; D005865:Gestational Age; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007231:Infant, Newborn; D008297:Male; D009200:Myocardial Contraction / Q000502:physiology*; D011247:Pregnancy; D059285:Pregnancy, Twin; D011446:Prospective Studies; D012016:Reference Values; D013223:Statistics as Topic; D013599:Systole / Q000502:physiology*; D016216:Ultrasonography, Prenatal