[Heart muscle involvement in myopathies].

By means of a comprehensive cardiologic examination "definite" cardiac involvement was found in 71% of patients with myotonic dystrophy (MD). In 50% of patients with Becker's muscular dystrophy (BMD) and in 70% of patients with mitochondrial myopathy (MMP). "Equivocal" cardiac involvement was found in 21% of patients with MD, in 50% of patients with BMD and in 20% of patients with MMP. The correlation between cardiac involvement and the neurological deficit was weak.