Orszulak, Michał, 1st Department of Cardiology; Medical University of Silesia, Katowice, Poland Orszulak, Michał, 1st Department of Cardiology, School of Medicine in Katowice, Medical University of Silesia, Upper-Silesian Medical Centre, Katowice, Poland (Poland) Orszulak, Michał Orszulak, Witold Orszulak-Michalak, Daria Ortega Marcos, Javier Ortenzi, Mariano, U.O.C. Diagnostica per Immagini, Ospedale Belcolle, Viterbo Orwat, Stefan, Department of Cardiology and Angiology, Adult Congenital and Valvular Heart Disease Centre, University Hospital of Muenster, Muenster, Germany Oryshchyn, Nelya Orzan, Marius Orzan, Rares-Ilie Orzałkiewicz, Mateusz Orzałkiewicz, Zbigniew Orzech, Jakub W Orzechowska, Agata Orzechowska, Anna Orzechowski, Piotr Orzeszko, Jacek Orłowska-Baranowska, Ewa, Institute of Cardiology, Warsaw Orłowska-Baranowska, Ewa Orłowska-Baranowska, Ewa (Poland) Orłowska−Baranowska, Ewa Orłowski, Tomasz, wojskowy Instytut Medyczny Osadnik, Sonia, Jagiellonian University Medical College Osadnik, Tadeusz, 3rd Chair and Department of Cardiology, Medical University of Silesia in Katowice, School of Medicine with the Division of Dentistry in Zabrze, Silesian Center for Heart Diseases, Poland