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Timothy syndrome

Disease definition

A rare, multiple congenital anomalies syndrome with cardiac involvement as a major feature characterized by QT prolongation, congenital heart defects, syndactyly, facial dysmorphism and neurodevelopmental features. There are three clinical phenotypes recognized, the classical types that present with a prolonged QT interval and either with (TS1) or without (TS2) cutaneous syndactyly of fingers and toes. The atypical form (ATS) causes multi-system health concerns but not necessarily with prolonged QT.


Classification level: Disorder
  • Synonym(s):
    • LQT8
    • Long QT syndrome type 8
    • Long QT syndrome-syndactyly syndrome
  • Prevalence: <1 / 1 000 000
  • Inheritance: Autosomal dominant 
  • Age of onset: Neonatal, Antenatal
  • ICD-10: I49.8
  • OMIM: 601005  618447
  • UMLS: C1832916
  • MeSH: C536962
  • GARD: 9294
  • MedDRA: -

Detailed information

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