2nd Department of Cardiology, Attikon Hospital, National and Kapodistrian University of Athens, 1 Rimini Str., Chaidari, Attiki, Athens, Greece. Clinic for Cardiology and Electrophysiology, Evangelisches Krankenhaus Hagen-Haspe, Hagen, Germany. General Hospital of Athens "G.Gennimatas", Athens, Greece. Humanitas Clinical and Research Center IRCCS, Rozzano-Milan, Italy. Department of Biomedical Sciences, Humanitas University, Pieve Emanuele-Milan, Italy. Humanitas Research Hospital IRCCS, Rozzano-Milan, Italy. Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA. 2nd Department of Cardiology, Attikon Hospital, National and Kapodistrian University of Athens, 1 Rimini Str., Chaidari, Attiki, Athens, Greece. spdeftereos@gmail.com.