title: Pulmonary outflow tract obstruction in fetuses with complex congenital heart disease: predicting the need for neonatal intervention.
abstract: OBJECTIVE
  To identify prenatal echocardiographic markers that could predict the need for neonatal intervention in fetuses with right ventricular outflow tract obstruction.
  
  
  METHODS
  This was a retrospective study of 52 fetuses with right ventricular outflow tract obstruction. Echocardiograms were evaluated for fetuses with either two-ventricle anatomy with a large ventricular septal defect or single-ventricle anatomy. Fetuses with pulmonary atresia were excluded. Parameters were compared between groups that did and did not require an intervention at age < 30 days.
  
  
  RESULTS
  Fifty-two fetuses were studied; 20 (38%) underwent neonatal intervention and 32 (62%) did not. The most common diagnosis was tetralogy of Fallot (n = 32). Fetuses with two ventricles that required an intervention had lower pulmonary valve diameter Z-score (PV-Z-score) (-4.8 ± 2.1 vs. -2.6 ± 1.1; P = 0.0002) and lower pulmonary valve to aortic valve annular diameter ratio (PV/AoV) (0.53 ± 0.15 vs. 0.66 ± 0.1; P = 0.003). Using a PV/AoV ratio of < 0.6 or a PV-Z-score of < -3 at final echocardiographic examination was highly sensitive (92%) but poorly specific (50%), whereas classifying direction of flow in the ductus arteriosus as either normal (all pulmonary-to-aorta) or abnormal (aorta-to-pulmonary or bidirectional) was both highly sensitive (100%) and specific (95%) for predicting the need for a neonatal intervention. Parameters for the single-ventricle cohort did not reach statistical significance.
  
  
  CONCLUSIONS
  Analysis of the pulmonary outflow tract and ductus arteriosus flow in the fetus with complex congenital heart disease can aid in identifying those that will require a neonatal intervention to augment pulmonary blood flow. This has important implications for the planning of delivery strategies.
authors.affiliation: Fetal Heart Program at the Cardiac Center, The Children's Hospital of Philadelphia, Philadelphia, PA, USA. mquarter@wakehealth.edu
authors.forename: M D
authors.initials: MD
authors.lastname: Quartermain
authors.forename: A C
authors.initials: AC
authors.lastname: Glatz
authors.forename: D J
authors.initials: DJ
authors.lastname: Goldberg
authors.forename: M S
authors.initials: MS
authors.lastname: Cohen
authors.forename: M D
authors.initials: MD
authors.lastname: Elias
authors.forename: Z
authors.initials: Z
authors.lastname: Tian
authors.forename: J
authors.initials: J
authors.lastname: Rychik
mesh_terms: D015150:Echocardiography, Doppler / Q000379:methods*; D018619:Echocardiography, Doppler, Pulsed / Q000379:methods*; D005544:Forecasting; D005865:Gestational Age; D006345:Heart Septal Defects, Ventricular / Q000000981:diagnostic imaging* / Q000628:therapy; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D007231:Infant, Newborn; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013771:Tetralogy of Fallot / Q000000981:diagnostic imaging* / Q000628:therapy; D016216:Ultrasonography, Prenatal / Q000379:methods*; D014694:Ventricular Outflow Obstruction / Q000000981:diagnostic imaging* / Q000628:therapy