1. Faculty of Medicine, University of Nis
2. Institute for Treatment and Rehabilitation Niska Banja
3. Department for Cardiovascular Diseases, Clinical Center Nis, Nis, Serbia
4. Cardiology Department, University of Medicine Rostock, Rostock
5. Clinic for Internal Diseases Intermedica, Singidunum University Nis, Jovana Ristica, Nis, Serbia
6. Veterans Affair Medical Centre, Washington DC, USA