Ventricular tachycardia: first manifestation of myotonic dystrophy.

Myotonic dystrophy type 1 (DM1) is the most frequent muscular dystrophy in adults. It is a multisystem disorder also affecting the heart with an increased incidence of sudden cardiac death. We present a young female patient with ventricular tachycardia (VT) who had no cardiac complaints previously. In this patient, the phenotypic characteristics implying DM1, neuromuscular testing and genetic analysis all confirmed the diagnosis of DM1 and because of the malignant nature of VT, she received an implantable cardioverter/defibrillator.