1. Department of Cardiology, Leiden University Medical Center , Albinusdreef 2 , 2300 RC Leiden, The Netherlands
2. Department of Cardiology, Jessa Hospital , Stadsomvaart 11 , 3500 Hasselt, Belgium
3. Department of Cardiology, Universitair Ziekenhuis Brussel , Laarbeeklaan 101 , 1090 Brussels, Belgium
4. Department of Cardiology, Turku Heart Center, University of Turku and Turku University Hospital , Kiinamyllynkatu 4-8 , FI-20520 Turku, Finland