Department of Cardiology, National and Kapodistrian University of Athens, Hippokration Hospital, Athens, Greece; Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland. Electronic address: mikevavuranakis@gmail.com. Department of Cardiology, National and Kapodistrian University of Athens, Hippokration Hospital, Athens, Greece. Onassis Cardiac Surgery Center, Kallithea, Greece. Department of Cardiology, National and Kapodistrian University of Athens, Hippokration Hospital, Athens, Greece; Department of Cardiology, National and Kapodistrian University of Athens, Sotiria Hospital, Athens, Greece. Department of Cardiology, National and Kapodistrian University of Athens, Sotiria Hospital, Athens, Greece. Agios Savvas - Anticancer Hospital, Athens, Greece. Aiginiteio University Hospital, Athens, Greece. General Hospital of Athens "G. Gennimatas", Athens, Greece. Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland.