[Dilated cardiomyopathy: role of clinical and instrumental evaluation of the neuromuscular system].

There are a number of cardiomyopathies secondary to a more widespread striated muscle involvement. While in some conditions the heart is affected as part of a severe myopathy (such as the dilated cardiomyopathy found in Duchenne and Becker muscular dystrophies), there are examples in which the skeletal muscle involvement is subtle. From a classification point of view, some of these cardiomyopathies are secondary to muscular dystrophies, or to metabolic disorders, or to other myopathies. From a practical diagnostic point of view, metabolic conditions predominate in infancy, whereas the dystrophic forms are more frequently found from the third decade onwards. Useful clinical clues to suggest a skeletal muscle involvement are muscle hypertrophy or wasting and contractures, in addition to weakness. Serum creatine kinase should always be studied when suspecting a form secondary to a muscular dystrophy, although a normal serum creatine kinase does not exclude a muscular dystrophy. Electromyography and muscle imaging are additional useful investigations in these patients. This article is focused on practical clinical suggestions on when to suspect and how to investigate patients with a cardiomyopathy secondary to neuromuscular disorders.