title: Outcome of children with fetal, neonatal or childhood diagnosis of isolated congenital atrioventricular block. A single institution's experience of 30 years.
abstract: OBJECTIVE
  We reviewed our institution's experience with isolated (congenital) third-degree atrioventricular block (CAVB) to identify pre- and post-natal predictors of mortality and the requirement for pacemakers in infancy and childhood.
  
  
  BACKGROUND
  Because of the relative rarity of the disease, there is a paucity of data concerning the outcome of fetuses and children with isolated CAVB.
  
  
  METHODS
  The medical records of all cases of CAVB encountered at our institution from January 1965 to December 1998 were analyzed.
  
  
  RESULTS
  Of 102 cases identified, 29 were diagnosed in utero (F) at 26.1 +/- 5.6 weeks gestation, 33 as neonates (N; < or = 28 days), and 40 as children (C) at 5.7 +/- 4.8 years of age. Anti-Ro and/or anti-La were present in 95% of F and 90% of N, but only in 5% of C mothers tested (p < 0.0001). Patients with CAVB having F, N and C diagnosis had a mortality of 43%, 6% and 0%, respectively, in the first two decades of life. Increased mortality risk was associated with a fetal diagnosis of CAVB (13/15 deaths; p < 0.05), fetal hydrops (6/6 cases; p < 0.0001), endocardial fibroelastosis (5/5 cases; p < 0.0001) and delivery at < or = 32 weeks (4/6 cases; p < 0.05). Timing of pacemaker implantation differed significantly among F versus N (p < 0.05) and N versus C (p < 0.001) cases. At 20 years of age only 11% and 12% of CAVB patients with N and C diagnosis, respectively, were not paced.
  
  
  CONCLUSIONS
  Pre-natal diagnosis of CAVB is associated with high fetal and neonatal mortality. Among survivors, whether the diagnosis is made before or after birth, most undergo pacemaker implantation by adulthood, with earlier intervention and a significantly greater need for reintervention among those diagnosed in utero.
authors.affiliation: Division of Cardiology, The Hospital for Sick Children, University of Toronto, Canada.
authors.forename: Edgar T
authors.initials: ET
authors.lastname: Jaeggi
authors.forename: Robert M
authors.initials: RM
authors.lastname: Hamilton
authors.forename: Earl D
authors.initials: ED
authors.lastname: Silverman
authors.forename: Samuel A
authors.initials: SA
authors.lastname: Zamora
authors.forename: Lisa K
authors.initials: LK
authors.lastname: Hornberger
mesh_terms: D000367:Age Factors; D002648:Child; D005260:Female; D005315:Fetal Diseases / Q000000981:diagnostic imaging; D006327:Heart Block / Q000175:diagnosis / Q000401:mortality* / Q000628:therapy; D006801:Humans; D015160:Hydrops Fetalis / Q000150:complications; D008297:Male; D010138:Pacemaker, Artificial; D011296:Prenatal Diagnosis; D012307:Risk Factors; D016019:Survival Analysis; D014463:Ultrasonography