A family with inherited congestive cardiomyopathy is presented. The diagnosis is based on clinical, morphological and laboratory evaluations. The first observed sign of the disease is arrhythmia and/or conduction defects. The onset of symptoms of pump failure is in adult life, and affected persons die within several years. Three persons have died suddenly. Septal hypertrophy was present in two affected persons. The mode of transmission is probably autosomal dominant. The recognition of arrhythmia as an early sign of the disease offers the opportunity of an early diagnosis.