Idiopathic cardiomyopathy and skeletal muscle abnormality.

The skeletal muscle of three cases presenting with idiopathic congestive cardiomyopathy has been studied, histologically, histochemically, ultramicroscopically, and electromyographically. In all three there is clinical evidence of skeletal muscle weakness, and in all three, pathologic changes were found in the muscle. These changes were different in each case and varied from mitochondrial myopathy to spinal atrophy to vacuolar myopathy. Other reported cases of cardiomyopathy demonstrating skeletal muscle pathology are discussed.