1. Department of Cardiology Policlinico Casilino of Rome Rome Italy
2. Pauley Heart Center Division of Cardiology Department of Internal Medicine Virginia Commonwealth University Richmond Virginia USA
3. Department of Cardiology Cardiocenter Third Faculty of Medicine Charles University University Hospital Kralovske Vinohrady Prague Czech Republic
4. 1st Department of Internal Medicine – Cardiology and Angiology University Hospital and Charles University Medical Faculty Hradec Kralove Czech Republic