1. Department of Cardiovascular Diseases, University Hospitals Leuven , Herestraat 49, 3000 Leuven , Belgium
2. Department of Cardiology, Gazi University Faculty of Medicine , Ankara , Turkey
3. Department of Cardiology, University Medical Centre Ljubljana, Slovenia Faculty of Medicine, University of Ljubljana , Ljubljana , Slovenia
4. Department of Pulmonology, University Hospitals Leuven , Leuven , Belgium