1. Department of Cardiology, Oslo University Hospital, Rikshospitalet, Norway
2. Center for Cardiological Innovation, Oslo University Hospital, Rikshospitalet, Norway
3. Institute for Surgical Research, Oslo University Hospital, Rikshospitalet, Norway
4. Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
5. Department of Paediatric Medicine, Oslo University Hospital, Rikshospitalet, Norway
6. University of Oslo, Norway