Pacing for conduction disturbances in Steinert's disease: a new indication for biventricular ICD?

Cardiac involvement in classical Steinert muscular dystrophy (dystrophia myotonica, MD1) is characterised by atrial arrhythmias, AV conduction disturbance, ventricular arrhythmias and heart failure. In MD1 patients complaints of fatigue and reduced exercise tolerance are well explained by the muscular weakness, but the same symptoms can be attributed to arrhythmia, atrioventricular block and heart failure. As cardiac pathology is often encountered in MD1 patients, an ECG, echocardiogram and Holter registrations should be performed on a routine basis. We report on two patients with MD1 who developed Mobitz II block as initial presentation of cardiac disease.