1. Department of Cardiovascular Disease, Mayo Clinic, Rochester, MN, USA
2. Valve Science Research Center Minneapolis Heart Institute, 100 3rd Ave S, Minneapolis, MN 55401, USA
3. Division of Cardiology, Cardiocentro Ticino Institute, Ente Ospedaliero Cantonale, Lugano, Switzerland
4. Department of Biomedical Sciences, Università della Svizzera Italiana, Lugano, Switzerland
5. Department of Cardiac Surgery, HerzZentrum Hirslanden, Zurich, Switzerland
6. Department of Cardiac Surgery, University of Zurich, Zurich, Switzerland
7. Division of Cardiology, Azienda Sanitaria Locale Torino 4, Ciriè, Italy
8. Department of Cardiology, University of Campus Biomedico, Rome, Italy
9. Department of Cardiology, Amiens University Hospital, Amiens, France
10. Division of Cardiology, Cliniques Universitaires Saint-Luc, Brussels, Belgium
11. Service of Clinical Epidemiology and Biometry, Policlinico San Matteo, Pavia, Italy