1. Department of Adult and Pediatric Cardiovascular Surgery, University Hospital Giessens, Giessen, Germany
2. Department of Cardiovascular Surgery, Robert-Bosch-Hospital, Stuttgart, Germany
3. Department of Cardiac Surgery, Cardiovascular Center Bad Neustadt, Bad Neustadt a. d. Saale, Germany
4. Department of Cardiology and Angiology, University Hospital Giessen, Giessen, Germany
5. Department of Cardiothoracic and Vascular Surgery, University Hospital Tübingen, Tübingen, Germany
6. Division of Cardiology, Angiology and Intensive Medical Care, Department of Internal Medicine III, University Hospital Halle, Halle (Saale), Germany