title: Ultrasonographic diagnosis of delayed atrioventricular conduction during fetal life: a reliability study.
abstract: OBJECTIVE
  The objective of the study was to evaluate the reliability of the 2 most commonly used ultrasonographic approaches for monitoring fetal atrioventricular conduction time (AVCT): (1) superior vena cava/ascending aorta (SVC/AA), and (2) left ventricular inflow/outflow tract (LVI/O) Doppler recordings.
  
  
  METHODS
  Echographic studies from fetuses followed up for first-degree atrioventricular block (AVB-1) between 1998 and 2008 were reviewed. The ability to identify atrial contractions in the same fetuses by the SVC/AA and LVI/O approaches was analyzed.
  
  
  RESULTS
  Sixty-six studies of 13 fetuses with AVB-1 were available. Atrial contractions were visible in all SVC/AA studies. With the LVI/O approach, atrial contractions could not be identified in 26 studies (39%). AVCT delay was significantly greater in the nonidentifiable compared with the identifiable atrial contraction group (P < .001). Differences in heart rate and gestational age were not significant.
  
  
  CONCLUSIONS
  The LVI/O is unsuitable for prenatal screening of conduction system anomalies.
authors.affiliation: Cardiology Division, Fetal Cardiology Unit, Department of Pediatrics, Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Montreal, QC, Canada.
authors.forename: Yvan
authors.initials: Y
authors.lastname: Mivelaz
authors.forename: Marie Josée
authors.initials: MJ
authors.lastname: Raboisson
authors.forename: Sylvia
authors.initials: S
authors.lastname: Abadir
authors.forename: Georgia
authors.initials: G
authors.lastname: Sarquella-Brugada
authors.forename: Anne
authors.initials: A
authors.lastname: Fournier
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Fouron
mesh_terms: D001011:Aorta / Q000000981:diagnostic imaging; D054537:Atrioventricular Block / Q000000981:diagnostic imaging* / Q000196:embryology; D015331:Cohort Studies; D015150:Echocardiography, Doppler / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D005315:Fetal Diseases / Q000000981:diagnostic imaging*; D005323:Fetal Monitoring / Q000379:methods; D005865:Gestational Age; D006329:Heart Conduction System / Q000000981:diagnostic imaging / Q000196:embryology*; D006339:Heart Rate / Q000502:physiology; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006801:Humans; D009200:Myocardial Contraction / Q000502:physiology; D011247:Pregnancy; D015203:Reproducibility of Results; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal; D014683:Vena Cava, Superior / Q000000981:diagnostic imaging; D014694:Ventricular Outflow Obstruction / Q000000981:diagnostic imaging