Examination of patients includes routine testing like electrocardiogram (ECG), sequential ECGs, exercise testing, invasive electrophysiological stimulation, cardiac magnetic resonance imaging, intravenous drug challenge for identification/exclusion of eg Brugada syndrome. Examples are patients with Long QT Syndrome, Short QT Syndrome, Brugada Syndrome, familial atrial fibrillation, WPW-syndrome, arrhythmias due to familial hypertrophic cardiomyopathy or arrhythmogenic right ventricular dysplasia. Blood samples are taken for further molecular genetic screening.