1. Department of Cardiothoracic Surgery, Royal Brompton and Harefield NHS Foundation Trust, Harefield, Middlesex, London, United Kingdom
2. Department of Cardiac Surgery, Heart and Marfan Center – University of Heidelberg, Heidelberg, Germany
3. Department of Cardiovascular Surgery, Charité-Universitätsmedizin Berlin, Berlin, Germany
4. Department of Cardiothoracic Surgery, Heart Center, University of Cologne, Cologne, Germany