Cardiac involvement in female carriers of duchenne or becker muscular dystrophy

The significance of abnormal cardiac measures in asymptomatic females who harbor dystrophin gene mutations is controversial. Methods Echo‐measures of ventricular function were compared with published norms in a cross‐sectional study of 130 (age, 39 ± 15.7 years) “carriers” of Duchenne or Becker muscular dystrophy (DMD/BMD). Correlations between cardiomyopathy (CM) and mutation, creatine kinase (CK) levels, age, and muscle symptoms were investigated. Results Depending on definition, CM prevalence was 3–33%. Ejection fraction (Simpson method) was < 55% in 9 (13%) and < 40% in 2 (2.9%). Eleven (8.5%) had wall motion abnormalities. Left ventricular end‐systolic dimensions were increased in 7 (5.7%) and end‐diastolic in 17 (13.9%). CM did not correlate with mutation type, DMD or BMD phenotype, CK level, muscle symptoms, or age. Conclusions Occult CM can be found by screening in DMD/BMD carriers. Its lack of age‐correlation suggests that not all abnormalities progress. Optimum screening schedules require a better understanding of progressive CM. Muscle Nerve 55 : 810–818, 2017