1. Department of Clinical Sciences Lund, Clinical Physiology and Skåne University Hospital Lund University Lund Sweden
2. Department of Health, Medicine and Caring Sciences, Unit of Health Care Analysis Linköping University Linköping Sweden
3. Actelion Pharmaceuticals Ltd. Allschwil Switzerland
4. Department of Clinical Sciences Lund, Cardiothoracic Surgery and Medicine Services University Trust Lund University Lund Sweden