1. Division for Adult Congenital Heart Disease, Department of Cardiovascular Medicine University Hospital Centre Zagreb Zagreb Croatia
2. Adult Congenital Heart Centre and National Centre for Pulmonary Hypertension Royal Brompton Hospital London UK
3. ACHD Centre, Department of Cardiology and Angiology of Medical Faculty Slovak Medical University and National Institute of Cardiovascular Diseases Bratislava Slovakia
4. Faculty of Medicine University of Belgrade Belgrade Serbia
5. Adult Congenital Heart Centre University Medical Center Ljubljana Slovenia
6. Cardiovascular Centre University Hospital Motol Prague Czech Republic
7. Department of Cardiology Gottsegen György Hungarian Institute of Cardiology Budapest Hungary
8. Hatter Institute for Clinic of Cardiac and Vascular Diseases, Faculty of Medicine Vilnius University Vilnius Lithuania
9. Ukrainian Children's Cardiac Center Kyiv Ukraine
10. Department of Cardiac and Vascular Diseases Institute of Cardiology, Jagiellonian University Medical College, John Paul II Hospital Kraków Poland
11. Department of Cardiology University Hospital St. Ekaterina Sofia Bulgaria
12. Clinic of Cardiology, Clinical Center Banja Luka, School of Medicine University of Banja Luka Banja Luka Bosnia and Herzegovina
13. Department of Cardiac surgery Tartu University Hospital Tartu Estonia
14. Pauls Stradins Clinical University hospital, Latvian Center of Cardiology, Riga University of Latvia Riga Latvia
15. University of Medicine and Pharmacy “Carol Davila”, Institute of Cardiovascular Diseases “Prof Dr C.C. Iliescu” Bucharest Romania
16. Erasmus Medical Center Rotterdam The Netherlands
17. Division of Adult Congenital and Valvular Heart Disease, Department of Cardiovascular Medicine University Hospital Muenster Muenster Germany