1 University Hospital of Larissa, University of Thessaly, Greece; School of Medicine, European University Cyprus, Cyprus, Greece.
2 Lankenau Institute for Medical Research, Wynnewood, Pennsylvania, USA.
3 Kaufman Center for Heart Failure Treatment and Recovery, Heart, Vascular, and Thoracic Institute, Cleveland Clinic, Cleveland, Ohio, USA. Electronic address: rcstarling@hotmail.com.