1. Department of Cardiac and Vascular Surgery, Rotenburg Heart and Vascular Centre, 36199 Rotenburg an der Fulda, Germany
2. Department of Cardiac and Vascular Surgery, Klinikum Karlsburg, Heart and Diabetes Center Mecklenburg-Western Pommerania, 17495 Carlsburg, Germany
3. Department of Cardiac Surgery, Marburg University Hospital, Philipps University of Marburg, Baldingerstrasse, 35043 Marburg, Germany
4. Department of Cardiology, Rotenburg Heart and Vascular Centre, 36199 Rotenburg an der Fulda, Germany
5. Department of Cardiology, Giessen University Hospital, 35392 Giessen, Germany