1. Department of cardiology, Gentofte Hospital, Gentofte Hospitalsvej 1 , 2900 Hellerup , Denmark
2. Department of cardiology, The Heart Centre, Rigshospitalet , Blegdamsvej 9, 2100 Copenhagen , Denmark
3. Department of cardiology, Rigshospitalet – Glostrup , Valdemar Hansens Vej 1, 2600 Glostrup , Denmark