1. Department of Pediatric Cardiology, University Hospital Tuebingen, Tuebingen, Germany
2. German Pediatric Heart Center, University of Bonn, Bonn, Germany
3. National Register for Congenital Heart Defects, Berlin, Germany
4. Division of Surgery for Congenital Heart Defects, Department of Cardiac Surgery, University of Hannover, Hannover, Germany
5. Clinic for Pediatric Cardiology and Congenital Heart Disease, Stuttgart, Germany
6. BQS Institute for Quality and Patient Safety, Hamburg, Germany
7. Division of Pediatric Cardiology and Pediatric Intensive Care, Ludwig Maximilian University of Munich, Munich, Germany
8. Clinic for Cardiac Surgery and Pediatric Cardiac Surgery Heart Center Duisburg, Duisburg, Germany