Summary:
The clinical picture of a number of hereditary familial neuromuscular diseases includes cardiac
affections. Depending on the type of muscular dystrophy the pathological changes may dominantly
affect the cardiac musculature or the specialized tissue of the cardiac conduction system. If the cardiac
chambers are affected cardiac disease is manifested as a cardiomyopathy, depending on the severity
of the disorder progressing to congestive heart failure. If the maximum of pathologi cal changes is
present in tissues of the cardiac conduction system, in the clinical picture dominate conduction
disorders and arrhythmias which may lead to sudden cardiac death. In some heredofamilial muscular
diseases we find a combination of both types of cardiac affection. Heredofamilial muscular diseases
which are characterized in addition to affection of skeletal muscles also by cardiac affection include
muscular dystrophies with defective synthesis of dystrophin and dystrophin associated glycoproteins,
myotonic dystrophies, Emery-Dreifuss muscular dystrophy and some mitochondrial diseases. In Eme-
ry-Dreifuss muscular dystrophy, myotonic dystrophy and some types of dystrophinopaties the cardiac
affection may be the first and/or dominant manifestation of the disease. In the first part of the review
the authors describe the affection of the heart in dystrophinopathies, where the cardiac disease is
a uniform part of all basic types of the disease. Dilating cardiomyopathy predominantes, the hypertro-
phic form and cardiac dysrhythmia are found less frequently. An exception are female carriers where the prevalence of hypertrophic cardiomyopathy is three times as frequent as the prevalence of the
dilating form. The incidence of preclinical and clinical cardiac affection progresses with the duration
of the disease and correlates indirectly with the functional demands on cardiac musculature which
depends on the severity of affection of the skeletal musculature. Therefore the prevalence of clinically
severe cardiomyopathies is higher in mobile patients (Becker’s form of dystrophino pathy) than in
patients confined to a wheelchair already in the early stages of the disease (Duchenne’s form). A special
form is X-linked dilating cardiomyopathy: it is mostly an isolated affection of the h eart with no or minor
affection of the skeletal muscles. The patients with all types of dystrophinopathiess should have regular
cardiological check-ups. Conversely examination for dystrophinopathies should be in young patients
of both sexes with idiopathic cardiopathies (dilatation and hypertrophy) a standard part of the
diagnostic algorithm.
Key words:
dystrophinopathy, dystrophin gene, cardiomyopathy, dysrhytmias
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