Could it be myotonic dystrophy? Myotonic dystrophy presenting with atrial flutter.

Myotonic dystrophy is a well recognised and well defined multisystem disorder which is inherited in an autosomal dominant fashion through a locus on chromosome 19. The disease itself is characterised by rigidity and degeneration of skeletal muscle, cataract formation, gonadal atrophy, frontal baldness and mental retardation. Like many inherited disorders there is a variable expression and so diverse clinical presentations can occur.