Duchenne muscular dystrophy (DMD), an X-linked recessive myopathy with an incidence of
1 in 3500 male births, is caused by a mutation that results in the absence of the cytoskeletal
protein dystrophin. 1, 2 The lack of dystrophin causes mechanical weakening of the
sarcolemma, which results in loss of membrane integrity, an inappropriate influx of calcium,
and altered cell signaling leading to activation of degradative pathways. 3-5 Thus, the
dystrophin-deficient myocardium provides the biologic substrate for the ultimate …