1. Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
2. Department of Cardiothoracic Surgery, Karolinska University Hospital, Stockholm, Sweden
3. Department of Cardiothoracic Surgery, Skåne University Hospital, Lund, Sweden
4. Section of Cardiac Surgery, Yale University School of Medicine, New Haven, CT, USA
5. Department of Surgery, Heart Center, Turku University Hospital, University of Turku, Turku, Finland
6. Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, Gothenburg, Sweden
7. Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
8. Department of Cardiothoracic Surgery, Heart Center Tampere University Hospital, Tampere, Finland
9. Department of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Skejby, Denmark
10. Department of Cardiothoracic and Vascular Surgery, Örebro University Hospital, Örebro, Sweden
11. Department of Cardiothoracic Surgery, Faculty of Medicine, Landspitali University Hospital, University of Iceland, Reykjavik, Iceland