Gloria Faerber1, Torsten Doenst2. 1. Department of Cardiothoracic Surgery, Jena University Hospital, Friedrich-Schiller-University of Jena, Jena, Germany. 2. Department of Cardiothoracic Surgery, Jena University Hospital, Friedrich-Schiller-University of Jena, Jena, Germany. Electronic address: doenst@med.uni-jena.de.