1. Division of Clinical Biochemistry, Innsbruck Biocenter, and
2. Departments of Pediatrics, Clinical Division of Pediatric Cardiology, and Internal Medicine, Clinical Division of Cardiology, Innsbruck Medical University, Austria
3. Department of Pediatric Cardiology, Pediatric Center, Linz, Austria
4. Department of Clinical Laboratory and Blood Depot, Gynaecologic and Pediatric District Hospital, Linz, Austria