1 Department of Cardiac Surgery and Transplantation, Medical University of Silesia in Katowice, School of Medicine with the Division of Dentistry in Zabrze, Silesian Center for Heart Diseases, Zabrze, Poland, Curie-Skłodowskiej 9, 41-800 Zabrze, Poland; Department of Heavy Cardiopulmonary Respiratory Failure and Mechanical Circulatory Support, Silesian Center for Heart Diseases, Zabrze, Poland, Curie-Skłodowskiej 9, 41-800 Zabrze, Poland. greg_kubiak@yahoo.com.