Cardiac and pulmonary investigations in Bethlem myopathy.
BACKGROUND
Bethlem myopathy is considered a relatively mild neuromuscular disorder without significant cardiac and respiratory involvement.


OBJECTIVE
To investigate cardiac and respiratory involvement in Bethlem myopathy.


METHODS
Cross-sectional study.


METHODS
University hospitals. Patients Fifty patients with Bethlem myopathy from 26 families.


METHODS
Cardiac examinations, including electrocardiography and echocardiography (n = 37) and pulmonary investigations (n = 43). Holter monitoring was performed in 16 patients.


METHODS
Cardiac and respiratory abnormalities.


RESULTS
Several cardiac abnormalities were found that were considered unrelated to the muscular disorder. Seven (16%) of 43 patients had a forced vital capacity less than 70% of the predicted value. One of 2 patients with a forced vital capacity less than 50% was also receiving respiratory support. All patients with compromised respiratory function were still ambulatory, and we found no significant correlation between the severity of arm weakness and the severity of respiratory muscle involvement.


CONCLUSIONS
There is no evidence of cardiac involvement in Bethlem myopathy. Respiratory failure is part of the clinical spectrum and can occur in ambulatory patients.
van der Kooi
Anneke J
AJ
Department of Neurology, Academic Medical Centre, University of Amsterdam, Amsterdam, the Netherlands. a.j.kooi@amc.uva.nl
de Voogt
Willem G
WG
Bertini
Enrico
E
Merlini
Luciano
L
Talim
F Beril
FB
Ben Yaou
Rabah
R
Urtziberea
Andoni
A
de Visser
Marianne
M
D000328:Adult; D000368:Aged; D009202:Cardiomyopathies / Q000209:etiology* / Q000473:pathology; D003430:Cross-Sectional Studies; D004452:Echocardiography / Q000379:methods; D004562:Electrocardiography / Q000379:methods; D005192:Family Health; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009136:Muscular Dystrophies / Q000150:complications* / Q000473:pathology; D012129:Respiratory Function Tests; D012132:Respiratory Muscles / Q000473:pathology / Q000503:physiopathology*