1. Department of Cardiology; University Medical Center Groningen, University of Groningen; Groningen The Netherlands
2. Department of Heart Diseases; Wroclaw Medical University; Wroclaw Poland
3. Laboratory for Applied Research on the Cardiovascular System; Wroclaw Medical University; Wroclaw Poland
4. Center for Heart Diseases; Military Hospital; Wroclaw Poland
5. Heart Failure Program, Hospital del Mar; Universitat Autonoma de Barcelona; Barcelona Spain
6. Silesian Center for Heart Disease and Silesian Medical University; Zabrze Poland