Dilated cardiomyopathy (DCM) is a severe disease of the heart muscle characterised by reduced pumping function and dilatation of the left ventricle without any obvious cause like hypertension, ischemic heart disease or heart valve disease. The patients often complain about shortness of breath, oedemas, and fatigability. The first sign of the disease can be a severe heart rhythm disorder without any preceding symptoms and DCM is not a rare cause of suddenly unexpected death. DCM is a frequent reason for heart transplantation and the prognosis is severe though improved over the last decades with the implementation of modern heart failure treatment.