1. Department of Pediatric Cardiology, University Hospital Aachen, 52074 Aachen, Germany
2. Department of Pediatric Cardiology, Centre Hospitalier Universitaire de Liège, 4000 Liège, Belgium
3. Department of Pediatric Cardiology, University Hospital Leuven, 3000 Leuven, Belgium
4. Department of Pediatric Cardiology, Children’s University Hospital Geneva, 1205 Geneva, Switzerland