1. Fourth Department of Internal Medicine, Medical School, National and Kapodistrian University of Athens, Attikon University Hospital, Athens, Greece
2. Third Department of Pediatrics, Medical School, National and Kapodistrian University of Athens, Attikon University Hospital, Athens, Greece
3. First Department of Cardiology, Medical School, National and Kapodistrian University of Athens, Hippokration Hospital, Athens, Greece
4. First Department of Cardiology, Korgialenio-Benakio General Hospital, Athens, Greece
5. Department of Pediatric Surgery, Medical School, National and Kapodistrian University of Athens, Attikon University Hospital, Athens, Greece