Efthymia Rouska1, Nikolaos Charokopos2, Ioannis Paralikas3, Christodoulos Pliakos4. 1. First Department of Cardiology, Evangelismos General Hospital, Athens, Greece. 2. Department of Cardiac Surgery, Euroclinic-Athens Hospital, 30 Nikitara St., Vrilissia, Attiki, 15235, Athens, Greece. nc.63@hotmail.com. 3. Department of Cardiac Surgery, Hellenic Navy General Hospital, Athens, Greece. 4. Department of Cardiology, AHEPA University Hospital, Thessaloniki, Greece.