1. Department of Cardiology, Leiden University Medical Center , Albinusdreef 2, 2300 RC Leiden , The Netherlands
2. Department of Cardiology, Jessa Hospital , 3500 Hasselt , Belgium
3. Department of Cardiology, Vrije Universiteit Brussel (VUB), Universitair Ziekenhuis Brussel (UZ Brussel) , 1090 Brussels , Belgium
4. Department of Cardiology, Turku Heart Center, University of Turku and Turku University Hospital , FI-20520 Turku , Finland