1. Cardiology Department, Larissa University Hospital, P.O. Box 1425, 41110 Larissa, Greece
2. Division of Cardiology, Emory University Hospital, Atlanta, GA 30322, USA
3. First Department of Internal Medicine, University of Athens Medical School, Athens, Greece
4. Department of General and Interventional Cardiology, University Heart Center Hamburg Eppendorf, Martinistraße 52, 20246 Hamburg, Germany