THE CARDIOMYOPATHY OF DUCHENNE BECKER CONSULTANTS

Clinical, electrocardiographic, echocardiographic and other instrumental examinations were performed on 233 persons primarily seeking genetic advice about the Duchenne/Becker gene in order to reveal the incidence of dystrophic cardiomyopathy in a population of females with a close relationship with patients suffering from Duchenne or Becker muscular dystrophy. Among these consultands, 210 were Duchenne and 23 Becker. Eighty-five (40.4%) Duchenne and 8 (34.8%) Becker consultands showed a normal cardiac status; 35 (16.6%) Duchenne and 6 (26.1%) Becker had clinically evident cardiomyopathy; 90 (43%) Duchenne and 9 (39.1%) Becker showed minor signs of myocardial involvement. The link between myocardial involvement and the Duchenne/Becker carrier condition was demonstrated through the observation that the percentage of cases showing pre-clinical or clinically evident cardiomyopathy was higher in the consultands with pathological values of serum creatine kinase activity (obligatory carriers) and/or an estimated genetic risk higher than 70% than in the consultands showing a normal value of serum creatine kinase activity (< 80 U/l) and/or a genetic risk lower than 70%.