Dilated Cardiomyopathy and Later Onset Limb-Girdle Muscular Dystrophy Associated With Fukutin and LaminA/C Mutations

Nonischemic dilated cardiomyopathy (DCM) can result from pathogenic variants in genes affecting myocardial structure and function. FKTN and LMNA mutations may involve both cardiac and skeletal muscle, consistent with limb-girdle muscular dystrophy (LGMD), with cardiac disease sometimes preceding neuromuscular symptoms.

We report on 2 adults presenting with advanced DCM requiring heart transplantation, who were later diagnosed with LGMD. A 22-year-old woman had biallelic FKTN variants, and a 37-year-old man carried a heterozygous LMNA pathogenic variant. Both had elevated creatine kinase prior to proximal muscle weakness. Muscle biopsy and genetic testing confirmed dystrophic processes.

These cases demonstrate that genetically mediated DCM may initially present as isolated cardiac disease. Early genetic testing can guide transplant planning, long-term care, and family counseling.