Cardiac involvement in the dystrophinopathies

The dystrophinopathies are a group of disorders that are characterized by absence or deficiency of functional dystrophin, a large cytoskeletal protein of striated muscle that is closely associated with transmembrane glycoprotein complexes. The most severe dystrophinopathy is Duchenne Muscular Dystrophy (DMD), a progressive disorder of all striated muscle that leads to death via cardiorespiratory failure in the second to third decades of life. Other dystrophinopathies include the similar but somewhat milder Becker Muscular Dystrophy (BMD) and X-linked dilated cardiomyopathy (XLDCM) where the cardiac manifestations predominate. While this review will focus specifically on the cardiac aspects of the dystrophinopathies, the principal elements of screening and monitoring cardiac status are applicable to patients with a broad range of myopathies and muscular dystrophies.