The aim of this study is the identification of familial congenital arrhythmogenic disorders and their clinical follow-up.

Molecular genetic screening in patients with:

• supraventricular
• ventricular arrhythmia
• syncopes of unknown origin and/or suspicion of an arrhythmogenic origin
• family members of patients with sudden cardiac death and aborted sudden cardiac death

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.

Inclusion Criteria:

• Patients with a history of syncope, abnormal ECG and suspicion of an arrhythmogenic disease
• Patients with long QT syndrome
• Patients with short QT syndrome, shortened QT intervals, borderline shortened QT intervals
• Patients with Brugada syndrome
• Patients with hypertrophic cardiomyopathy
• Patients with arrhythmogenic right ventricular dysplasia

Exclusion Criteria:

• Inability to understand study protocol

Consecutive patient sampling with history of syncope, aborted SCD, familial sudden cardiac death, high suspicion of familial cardiac arrhythmias.