1. Department of Cardiac and Vascular Surgery, Klinikum Karlsburg, Heart and Diabetes Center Mecklenburg-Western Pommerania, Germany
2. Department of Cardiac Surgery, University Hospital Mainz, Germany
3. Department of Cardiothoracic and Vascular Surgery, Ulm University Hospital, Germany
4. Department of Cardiac Surgery, Schuechtermann-Klinik, Bad Rothenfelde, Germany
5. Department of Cardiac Surgery and Surgical Intensive Care Medicine, Kerckhoff Heart Center, Bad Nauheim, Germany
6. Campus Kerckhoff, Justus-Liebig University Giessen, Germany