1. Comprehensive Heart Failure Center; University of Würzburg; Würzburg Germany
2. Hospital of Lithuanian University of Health Science; Kaunas Lithuania
3. University of Medicine and Pharmacy Carol Davila; University and Emergency Hospital; Bucharest Romania
4. Clinical Center of Serbia; Belgrade Serbia
5. University of Stavanger; Stavanger Norway
6. University Medical Center Göttingen; Germany
7. University of Athens; Athens Greece
8. Wroclaw Medical University; Wroclaw Poland
9. General Hospital Celje; Celje Slovenia