1. Department for Cardiovascular Diseases, Clinical Center Nis, 18000 Nis, Serbia
2. Faculty of Medicine, University of Nis, 18000 Nis, Serbia
3. Clinic for Nephrology, University Clinical Center Nis, 18000 Nis, Serbia
4. Institute for Treatment and Rehabilitation Niska Banja, 18000 Nis, Serbia
5. University Hospital Medical Center Bezanijska Kosa, 11000 Belgrade, Serbia