1. Department of Cardiac Surgery, Universitätsklinikum Bonn, Bonn, Nordrhein-Westfalen, Germany
2. Department of Cardiovascular Surgery, Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Mainz, Rheinland-Pfalz, Germany
3. Department of Anesthesiology and Intensive Care Medicine, Universitätsklinikum Bonn, Bonn, Nordrhein-Westfalen, Germany