Cardiac Abnormalities in Congenital and Childhood Myotonic Muscular Dystrophy Type 1

Myotonic dystrophy often presents with cardiac abnormalities, particularly conduction defects, that factor into an increased risk of sudden cardiac death. Myotonic dystrophy has two forms, myotonic dystrophy type 1 (DM1) and DM2, and is a multisystemic disorder that presents in a wide, clinical spectrum and age range. A distinguishing feature of DM1 is the existence of a congenital form. Though research on cardiac involvement has been conducted on patients with the adult form of myotonic dystrophy, there have been few studies focused on cardiac involvement in pediatric patients with congenital myotonic dystrophy type 1 (CDM1). In this study, a survey was conducted to determine the prevalence and variations of cardiac abnormalities in pediatric patients with CDM1. This preliminary study found a prevalence of 25.8% CDM1 pediatric patients with cardiac abnormalities in a sample size of 31 patients.