title: [Cardiac abnormalities in patients with myotonic dystrophy--preliminary results].
abstract: BACKGROUND
  Myotonic dystrophy (DM) is an inherited multisystem disorder associated with myotonia, progressive skeletal muscle weakness and atrophy, involvement of peripheral and central nervous system and sudden death likely due to atrioventricular block and/or ventricular arrhythmia.
  
  
  OBJECTIVE
  to assess the type and degree of cardiac and neurological involvement in patients (pts) with DM.
  
  
  METHODS
  10 pts (6 male), in mean age of 35 +/- 13 years, treated for DM type I (DM1)--7 pts and type II (DM2)--3 pts. All pts underwent a neurological examination including muscle strength assessment as well as cardiac diagnostics including: standard and 48-hour ambulatory electrocardiogram, echocardiographic examination, magnetic resonance imaging (MRI) of the heart and late potentials assessment.
  
  
  RESULTS
  Muscle strength was moderately diminished (46-48 points in MRC sub score) in 3 pts with DM1 and mildly diminished (56-58 points in MRC sub score) in 2 pts with DM2. These patients showed clinical symptoms of myopathy. Cardiovascular examinations revealed: QRS duration above 110 ms in 5 pts, clinically significant supraventricular arrhythmia or atrioventricular block in 3 pts, focal myocardial fibrosis in 3 pts, asymmetric hypertrophy of inter-ventricular septum in 1 patient, presence of late potentials in 5 pts. We have not observed correlation between impaired muscle strength and cardiac abnormalities. However, most pronounced cardiac abnormalities were observed in 2 male DM1 patients with clinical symptoms of myopathy and lowest MRC score. At a mean follow up of 3.2 +/- 1.4 years none of the pts died.
  
  
  CONCLUSIONS
  Cardiac involvement in pts with myotonic dystrophy is frequent and is characterized by phenotypic heterogeneity. Detection of cardiac abnormalities may require extensive diagnostics. The most important is the assessment of ECG. Cardiac and neurological abnormalities vary in intensity between patients without close relationship to each other.
authors.forename: Paweł
authors.initials: P
authors.lastname: Derejko
authors.forename: Marta
authors.initials: M
authors.lastname: Banach
authors.forename: Andrzej
authors.initials: A
authors.lastname: Hasiec
authors.forename: Jakub
authors.initials: J
authors.lastname: Antczak
authors.forename: Rafał
authors.initials: R
authors.lastname: Rola
authors.forename: Radosław
authors.initials: R
authors.lastname: Sierpiński
authors.forename: Jolanta
authors.initials: J
authors.lastname: Miśko
authors.forename: Anna
authors.initials: A
authors.lastname: Wójcik
authors.forename: Roman
authors.initials: R
authors.lastname: Kępski
authors.forename: Lukasz
authors.initials: L
authors.lastname: Szumowski
mesh_terms: D000328:Adult; D009202:Cardiomyopathies / Q000175:diagnosis* / Q000209:etiology*; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength; D009223:Myotonic Dystrophy / Q000150:complications* / Q000175:diagnosis