1. First Department of Pulmonary Medicine, Sismanoglio Hospital, Sismanogliou 1, Marousi, Greece
2. First Department of Cardiology, Hippokration Hospital, University of Athens, Vasilissis Sofias 114, Athens, Greece
3. Department of Cardiology, Helena Venizelou Hospital, Helenas Venizelou 2 Square, Ampelokipi, Greece