A 52-year-old man had a cardiomyopathy for 22 years as had his brother. Both required pacemakers. For the past 12 years, he also suffered from increasing muscle weakness. His muscle fibres contained granulo-filamentous material as previously seen in muscle fibres of a French family with myopathy and cardiomyopathy. It was rich in desmin, alpha-B crystallin, and dystrophin, the connotation, pathogenesis, and common denominator of which, however, remain unexplained.