Left ventricular hypertrabeculation in myotonic dystrophy Type 1

Background: Left ventricular hypertrabeculation (LVHT) has not been describ ed in myotonic dystrophy Type I (MD1) before. Case Report: A 42-year-old man developed typical features of MD1 since 1992 Creatinekinase was slightly, but recurrently elevated. Needle electromyogr ams were myogenic and showed extensive spontaneous activity. Muscle biopsy was compatible with MDI. DNA analysis revealed a heterozygous 300 CTG-repea t expansion in the myotonic-dystrophy proteinkinase gene on chromosome 19q1 3-3 Cardiac history and clinical cardiologic examination were normal. On EG G, ST elevation and atrial flutter were found. The AECG was normal except f or atrial flutter. Surprisingly, transthoracic echocardiography revealed LV HT, previously described only in Becker's muscular dystrophy, mitochondriop athies, and Earth syndrome. Conclusion: A ra re cardiac manifestation of MD1 may be LVHT which alone ha s no therapeutic implication.