1. Department of Cardiology, Asklepios Clinic St. Georg, 20099 Hamburg, Germany
2. Department of Cardiology and Cardiac Surgery, Kerckhoff Heart Center, 61231 Bad Nauheim, Germany
3. Department of Cardiothoracic Surgery, University of Regensburg Heart Center, 93053 Regensburg, Germany
4. Department of Cardiothoracic Surgery and Vascular Surgery, Clinic of Braunschweig, 38120 Braunschweig, Germany
5. Department of Cardiovascular Surgery, MediClin Herzzentrum Lahr/Baden, 77933 Lahr, Germany
6. Department of Cardiology and Angiology, Faculty of Medicine, Medical Center—University Heart Freiburg, University of Freiburg, 79189 Bad Krozingen, Germany
7. Department of Cardiology and Intensive Care Medicine, Klinikum Würzburg Mitte, 97070 Würzburg, Germany
8. Department of Cardiothoracic Surgery, Asklepios Clinic St. Georg, 20099 Hamburg, Germany