1. Department of Anesthesiology, Faculty of Medicine, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany
2. Department of Cardiothoracic Surgery, Heart Center Trier, Barmherzigen Brüder Hospital Trier, 54292 Trier, Germany
3. Department of Thoracic Surgery, Medical Faculty RWTH Aachen University, Pauwelsstrasse 30, 52074 Aachen, Germany
4. Abiomed Europe GmbH, 52074 Aachen, Germany
5. Department of Anesthesia, Critical Care and Pain Medicine, St. Johannes Hospital, 44137 Dortmund, Germany