1. Friedrich-Ebert Hospital, Medical Clinic, Friesenstr. 11, D 24531 Neumünster, Germany
2. Ospedale Loreto Mare, Naples, Italy
3. Onassis Cardiac Center, Athens, Greece
4. Hopital Pitie-Salpetriere, Paris, France
5. St Jude Medical, Zaventem, Belgium
6. St Jude Medical, Eschborn, Germany
7. Department of Heart and Vessel, University of Florence Cliniche Gavazzeni, Bergamo, Italy