1. First Cardiology Department, Onassis Cardiac Surgery Center, Athens, Greece
2. Internal Medicine Department, General Hospital of Kimi, Kimi, Greece
3. Department of Nursing, Technical School of Education, Athens, Greece
4. Medical School, University of Athens, Athens, Greece)
5. “Atticon” General Hospital, Athens, Greece (GK)
6. Department of Clinical Biochemistry (Vascular Prevention Clinics), Royal Free Hospital campus, University College Medical School, University College London, London, United Kingdom.