title: Short QT syndrome manifesting with neonatal atrial fibrillation and bradycardia.
abstract: OBJECTIVE
  Atrial fibrillation (AF) is rare during childhood and usually associated with other cardiovascular pathology. In lone AF, the ventricular response rate is usually rapid. We sought to describe a subset of children who present with early-onset AF and a slow ventricular response rate who were found to have the short QT syndrome (SQTS).
  
  
  METHODS
  Using a MEDLINE/PubMed search, children with AF, a structurally normal heart and bradycardia were identified. Demographics, clinical presentation, electrocardiographic (ECG) findings, electrophysiologic testing, genetic analysis and follow-up assessment were collected on each child for analysis.
  
  
  RESULTS
  Four children were identified in the literature and combined with 2 other children followed by the authors. All had a short QT interval and those who were tested were found to have a gain-of-function mutation in the KCNQ1 gene.
  
  
  CONCLUSIONS
  We describe a subclass of children with SQTS who present with AF and a slow ventricular response. Medical therapy has not been effective in maintaining sinus rhythm. The long-term outcome remains unknown for these children. This condition may present in utero as persistent bradycardia with postnatal ECG showing a very short QT interval.
authors.affiliation: Department of Pediatrics (Cardiology), University of Kentucky, Lexington, Ky., USA.
authors.forename: Juan
authors.initials: J
authors.lastname: Villafañe
authors.forename: Peter
authors.initials: P
authors.lastname: Fischbach
authors.forename: Roman
authors.initials: R
authors.lastname: Gebauer
mesh_terms: D001145:Arrhythmias, Cardiac / Q000150:complications / Q000235:genetics; D001281:Atrial Fibrillation / Q000150:complications / Q000235:genetics*; D001919:Bradycardia / Q000150:complications / Q000235:genetics*; D002648:Child; D004562:Electrocardiography; D005260:Female; D006579:Heterozygote; D006801:Humans; D051657:KCNQ1 Potassium Channel / Q000235:genetics*; D008297:Male; D009154:Mutation / Q000235:genetics*
chemical_list: D051657:KCNQ1 Potassium Channel; C496909:KCNQ1 protein, human