Department of Physiology, University Hospital Aachen, Germany (1989-1995)
Heart Center Lahr, Germany (1996)
Clinic for Thoracic- and Cardiovascular Surgery, University Hospital Aachen, Germany (1997-2004)
Research Dept. of the Clinic for Cardiovasc. Surgery, University Hospital Zurich (1999-2000)
Helmholtz Institute Aachen, Germany (2000-2001)
Interdisciplinary Center for Clinical Research on Biomaterials (2001-2002)
Institut National de Chirurgie Cardiaque et de Cardiologie Interventionelle, Luxembourg (2005)
Helmholtz Institut for Biomedical Engineering-Head of Cardiovascular Tissue Engineering (since 2006)
Development of New Oxygenation Systems
Cardiovascular Tissue Engineering