Neuromuscular changes in hypertrophic cardiomyopathy.

Clinical, electrophysiological and histological studies of skeletal muscle were performed in 12 patients with primary hypertrophic cardiomyopathy trying to add more information about the skeletal muscle affectation in this disease. Eight cases showed mild increase in serum enzymes. All of the patients showed slight abnormalities in the electrophysiologic studies: four had abnormal conduction velocities in peripheral nerve, another four a myopathic pattern in the EMG and four a mixed pattern. Histologically only 2 patients showed signs of a denervation atrophy. The most common alterations found were non-specific (isolated fibre atrophy, disorganization of the myofibrillar network and type II atrophy).