Short QT syndrome manifesting with neonatal atrial fibrillation and bradycardia

Cardiology. 2014;128(3):236-40. doi: 10.1159/000360758. Epub 2014 May 9.

Abstract

Objectives: 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.

Publication types

  • Case Reports
  • Review

MeSH terms

  • Arrhythmias, Cardiac / complications
  • Arrhythmias, Cardiac / genetics
  • Atrial Fibrillation / complications
  • Atrial Fibrillation / genetics*
  • Bradycardia / complications
  • Bradycardia / genetics*
  • Child
  • Electrocardiography
  • Female
  • Heterozygote
  • Humans
  • KCNQ1 Potassium Channel / genetics*
  • Male
  • Mutation / genetics*

Substances

  • KCNQ1 Potassium Channel
  • KCNQ1 protein, human

Supplementary concepts

  • Short Qt Syndrome