Successful termination of ventricular arrhythmias with implantable cardioverter defibrillator in a patient with myotonic dystrophy

Myotonic dystrophy (DM) is one of the most frequent adulthood diseases of the skeletal muscles, which develops multisystemic features and shows autosomal dominant trait. In DM, tissue degeneration affects not only the skeletal, but the cardiac muscle, too. In one third of the patients, the cause of death is of cardiac origin. We report on our patient's case, who was diagnosed with DM at the age of 52, in whom episodes of critical bradycardia with first-degree atrioventricular block was detected, resulting in a pacemaker implantation. Invasive cardiac electrophysiological study was performed, during which ventricular fibrillation was registered. A shock electrode was added to the previously implanted pacemaker, enabling defibrillation in case of detection of a sustained ventricular arrhythmia. During the 1-year followup, 22 episodes of sustained ventricular tachycardia were identified, with the device successfully terminating the malignant arrhythmias. Our case shows that electrophysiological study and the succeeding implantation of an implantable cardiac defibrillator is highly important in identifying and terminating ventricular arrhythmias in high-risk DM patients.