title: Normative Values of Aortic Arch Structures in Premature Infants.
abstract: BACKGROUND
  Aortic arch abnormalities represent 5% to 8% of all congenital heart disease. Measurements of the aortic arch dimensions on two-dimensional echocardiographic images remain of critical importance in the diagnosis of aortic arch pathology. To define aortic hypoplasia or coarctation, measured dimensions must be compared with normal values. Normal values have been described for children of all ages in earlier studies. However, normative data for premature infants are not yet available. Therefore, the aim of this study was to develop normative data in a cohort of premature infants, which could be used in the diagnosis of aortic arch abnormalities.
  
  
  METHODS
  A single-center study was conducted in a large population of premature infants with gestational ages of ≤32 weeks without hemodynamically important congenital heart disease, chromosomal abnormalities, and/or major cerebral congenital malformations. Two-dimensional echocardiographic measurements of four aortic arch structures were made on the second, fourth, and sixth days after birth.
  
  
  RESULTS
  Three hundred eighty-five preterm patients were included. No differences in dimensions were found among days 2, 4, and 6. The dimension of the isthmus showed no significant relation to the existence of a patent ductus arteriosus. Reference intervals with mean and SD were calculated across the range of birth weight. Regression analysis was performed with multiple determinants in different models. The best predictive value was found for birth weight in a cubic model.
  
  
  CONCLUSIONS
  This work provides regression equations for the calculation of Z scores and reference intervals for aortic arch dimensions in a cohort of preterm infants born at gestational ages of ≤32 weeks. The normative data can be used in diagnosis and decision making involving aortic arch pathology in premature infants.
authors.affiliation: Department of Pediatric Cardiology, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands. Electronic address: edijkema@umcutrecht.nl.
authors.forename: Elles J
authors.initials: EJ
authors.lastname: Dijkema
authors.affiliation: Department of Pediatric Cardiology, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Mirella C
authors.initials: MC
authors.lastname: Molenschot
authors.affiliation: Department of Pediatric Cardiology, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Johannes M P J
authors.initials: JM
authors.lastname: Breur
authors.affiliation: Department of Neonatology, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Willem B
authors.initials: WB
authors.lastname: de Vries
authors.affiliation: Department of Pediatric Cardiology, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Martijn G
authors.initials: MG
authors.lastname: Slieker
mesh_terms: D001013:Aorta, Thoracic / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D004452:Echocardiography / Q000592:standards* / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000592:standards*; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: Aortic arch; Echocardiography; Infants; Premature; Reference values; Regression analysis