1. Medical Clinic/Cardiology, Asklepios Klinik Barmbek, Ruebenkamp 220, 22291 Hamburg, Germany
2. Department of Cardiac Surgery, Asklepios Klinik St. Georg, Lohmuehlenstraße 5, 20099 Hamburg, Germany
3. Medical Clinic/Cardiology, Asklepios Klinik Altona, Paul-Ehrlich-Straße 1, 22763 Hamburg, Germany