1. Department of Cardiac Surgery, Vienna General Hospital, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
2. Division of Cardiovascular Surgery, University of Pennsylvania Medical Center, 3400 Spruce Street, Philadelphia, PA 19104, USA
3. Department of Dermatology, Vienna General Hospital, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria