Drug-refractory Heart Failure in Female Carrier of Duchenne Muscular Dystrophy: A Case of X-linked Dilated Cardiomyopathy

A 56-year-old woman was referred to our hospital for the further evaluation of drug-refractory heart failure with a reduced ejection fraction. A family history interview revealed that men in her family had died of Duchenne muscular dystrophy (DMD), whereas she had no skeletal muscle disorder. Myocardial histopathology revealed a reduced dystrophin expression in the cardiomyocyte membrane, and a dystrophin (DMD) gene analysis identified a duplication in exon 8-9 on Xp21, suggesting that she had a cardiac-specific phenotype of dystrophinopathy, i.e. X-linked dilated cardiomyopathy (XLDCM). In conclusion, careful family history interviews and an investigation of dystrophinopathy are required to detect XLDCM in women.

Automated summary

A 56-year-old woman with drug-refractory heart failure was found to have a family history of Duchenne muscular dystrophy (DMD). Despite not having skeletal muscle disorder, she exhibited reduced dystrophin expression in cardiac myocytes. Genetic analysis revealed a duplication in exon 8-9 on Xp21, indicating X-linked dilated cardiomyopathy (XLDCM) as a cardiac-specific phenotype of dystrophinopathy. Family history interviews and dystrophinopathy investigation are necessary for detecting XLDCM in women.