1. University of Zurich, Zurich, Switzerland
2. University of Michigan, Ann Arbor, USA
3. Cardiology Centre, Zurich, Switzerland
4. Stadtspital Triemli, Zurich, Switzerland
5. Hôpital de La Tour, Geneva, Switzerland
6. CardioCentro Ticino, Lugano, Switzerland
7. Kantonsspital, St Gallen, Switzerland
8. Hôpital cantonal, Fribourg, Switzerland
9. Inselspital, Berne, Switzerland
10. Luzerner Kantonsspital, Lucerne, Switzerland