1. Department of Cardiology, Tzaneio General Hospital of Piraeus, 185 36 Piraeus, Greece
2. Echocardiography Training Center of Tzaneio ‘D. Beldekos’, 185 36 Piraeus, Greece
3. Department of Pediatric Cardiology and Adult Congenital Heart Disease, “Onassis” Cardiac Surgery Center, 176 74 Athens, Greece
4. First Department of Cardiology, AHEPA University Hospital, Aristotle University of Thessaloniki, 546 36 Thessaloniki, Greece