title: Syncope and hyperCKemia as minimal manifestations of short CTG repeat expansions in myotonic dystrophy type 1.
abstract: BACKGROUND
  Syncope and palpitations as the only initial manifestations of myotonic dystrophy type 1 (MD1) due to a CTG expansion of 50-100 repeats have not been reported.
  
  
  METHODS
  In a 55-year-old female with a family history of MD1 and a personal history of a single syncope, palpitations, and hyperCKemia, 70 CTG repeats were detected in the DMPK gene. Her brother had presented atypical clinical, electromyographic, and muscle biopsy features since the age of 35 but had been diagnosed with MD1 after he later developed typical distal myotonia. He died suddenly during an episode of syncope at the age of 53. A sister with clinical myotonia died suddenly during sleep at the age of 45 and a second sister with quadriparesis died from complications of intestinal rupture at age 52. A third sister committed suicide at age 40 after developing recurrent syncopes, while a fourth sister had hyperCKemia and foot-extensor weakness. The mother of these five affected children died suddenly from myocardial rupture.
  
  
  CONCLUSIONS
  MD1 with <100 CTG repeats may exclusively manifest cardiologically. Family screening for MD1 is important even in asymptomatic patients. MD1 may initially manifest without typical features, while muscle biopsy may be misleading and indicate glycogenosis. Close cardiac follow-up is important if MD1 manifests cardiologically to prevent syncope or sudden cardiac death.
authors.affiliation: Kar Vienna, Vienna, Austria. Electronic address: fifigs1@yahoo.de.
authors.forename: Josef
authors.initials: J
authors.lastname: Finsterer
authors.affiliation: Kar Vienna, Vienna, Austria.
authors.forename: Claudia
authors.initials: C
authors.lastname: Stöllberger
authors.affiliation: Kar Vienna, Vienna, Austria.
authors.forename: Martin
authors.initials: M
authors.lastname: Gencik
authors.affiliation: Kar Vienna, Vienna, Austria.
authors.forename: Romana
authors.initials: R
authors.lastname: Höftberger
authors.affiliation: Kar Vienna, Vienna, Austria.
authors.forename: Jasmin
authors.initials: J
authors.lastname: Rahimi
authors.affiliation: Kar Vienna, Vienna, Austria.
authors.forename: Johannes
authors.initials: J
authors.lastname: Mokocki
mesh_terms: D003402:Creatine Kinase / Q000097:blood*; D005260:Female; D006801:Humans; D008875:Middle Aged; D009223:Myotonic Dystrophy / Q000097:blood / Q000150:complications* / Q000235:genetics*; D010375:Pedigree; D013575:Syncope / Q000097:blood / Q000209:etiology*
chemical_list: D003402:Creatine Kinase
keywords: Arritmias ventriculares; Cardiac involvement; Curschman-Steinert disease; Distrofia miotónica; Doença de Curshman-Steinert; Envolvimento cardíaco; Myotonic dystrophy; Perturbação trinucleotide; Trinucleotide disorder; Ventricular arrhythmias