[Myotonic dystrophy and bundle-branch re-entrant tachycardia].

We report the case of a 37-year-old man diagnosed with myotonic dystrophy who presented atrial fibrillation with high ventricular rate. While being treated with amiodarone, he suffered cardiac arrest. The electrophysiological study disclosed bundle-branch reentrant ventricular tachycardia and ventricular fibrillation. Catheter ablation of the right bundle branch was performed and a bicameral defibrillator was implanted. The mechanisms and treatment of arrhythmias in these patients are discussed.