Marek A. Deja, MD, PhD is a Professor in the Department of Cardiac Surgery at the Medical University of Silesia. He received a Doctor of Medicine degree from the Medical University of Silesia. His research interests are Cardiac Surgery, Cardiology, Coronary Artery Bypass, Heart Valve Diseases, Heart Failure, Mitral Valve, Off-Pump Coronary Artery Bypass, Cardiothoracic Surgery.