title: Development of left ventricular longitudinal speckle tracking echocardiography in very low birth weight infants with and without bronchopulmonary dysplasia during the neonatal period.
abstract: OBJECTIVE
  In preterm infants, postnatal myocardial adaptation may be complicated by bronchopulmonary dysplasia (BPD). We aimed to describe the development of left ventricular function by serial 2D, Doppler, and speckle tracking echocardiography (2D-STE) in infants with and without BPD during the neonatal period and compare these to anthropometric and conventional hemodynamic parameters.
  
  
  METHODS
  Prospective echocardiography on day of life (DOL) 1, 7, 14, and 28 in 119 preterm infants <1500 g birth weight of whom 36 developed BPD (need for oxygen supplementation at 36 weeks gestational age). Non-BPD and BPD infants differed significantly in median (IQR) gestational age (25.5(24-26.5) weeks vs. 29(27-30) weeks, p<0.001) and birth weight (661(552-871) g vs. 1100(890-1290) g, p<0.001).
  
  
  RESULTS
  The intra- and inter-observer variability of the 2D-STE parameters measured did not depend on time of measurement, although there were significant differences in the reproducibility of the parameters. Low intra- and inter-observer variability was seen for longitudinal systolic strain and strain rate mid septum with a median CV (coefficient of variation) of <4.6%. Much higher CVs (>10%) were seen for the apical segment. While anthropometric parameters show rapid development during the first 4 weeks of life, the speckle tracking parameters did not differ statistically significantly during the neonatal period. Infants with and without BPD differed significantly (p<0.001) in the development of anthropometric parameters, conventional hemodynamic parameters except for heart rate, and 2D-STE parameters: global longitudinal systolic strain rate (GLSSR) and longitudinal systolic strain for the mid left wall (LSSR). The largest differences were seen at DOL 1 and 7 in GLSSR (p<0.001) and in LSSR (p<0.01).
  
  
  CONCLUSIONS
  Reproducible 2D-STE measurements are possible in preterm infants <1500 g. Cardiac deformation reveals early (DOL 1 and 7) ventricular changes (GLSSR and LSSR) in very low birth weight infants who develop BPD.
authors.affiliation: Department of Neonatology, Charité University Medical Center, Berlin, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Czernik
authors.affiliation: Department of Pediatric Cardiology, Charité University Medical Center, Berlin, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Rhode
authors.affiliation: Department of Pediatric Cardiology, Charité University Medical Center, Berlin, Germany.
authors.forename: Sven
authors.initials: S
authors.lastname: Helfer
authors.affiliation: Department of Neonatology, Charité University Medical Center, Berlin, Germany.
authors.forename: Gerd
authors.initials: G
authors.lastname: Schmalisch
authors.affiliation: Department of Neonatology, Charité University Medical Center, Berlin, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Bührer
authors.affiliation: Department of Pediatric Cardiology, Charité University Medical Center, Berlin, Germany.
authors.forename: Lothar
authors.initials: L
authors.lastname: Schmitz
mesh_terms: D000886:Anthropometry; D001794:Blood Pressure; D001997:Bronchopulmonary Dysplasia / Q000175:diagnosis / Q000503:physiopathology*; D004452:Echocardiography; D005260:Female; D006339:Heart Rate; D006352:Heart Ventricles / Q000503:physiopathology*; D006439:Hemodynamics; D006801:Humans; D007223:Infant; D007230:Infant, Low Birth Weight / Q000502:physiology; D007231:Infant, Newborn; D008297:Male; D016277:Ventricular Function, Left