Becker myotonia congenita associated with Wolff-Parkinson-White syndrome.

Becker's disease is a congenital myotonia with an autosomal recessive pattern of inheritance. Unlike myotonic dystrophy, it is not associated with cardiopathy. We present a 32-year-old man with Becker's disease diagnosed at age 11. He suffered episodes of loss of consciousness preceded by palpitations when he performed strenuous physical exercise. The electrocardiogram reveals a Wolff-Parkinson-White syndrome. Review of the literature in MEDLINE using the search terms of congenital myotonia or Becker's disease and arrhythmia or heart disease only found 2 articles on Thomsen disease but none on Becker's disease. Becker's myotonia congenita may exceptionally be associated with cardiopathy, thus patients with this disorder should have a cardiac evaluation.