1. Department of Pediatrics, Division of Cardiology, University of Alberta and Stollery Children's HospitalEdmonton Canada
2. Department of Cardiology, Boston Children's HospitalBoston Massachusetts
3. Department of Pediatrics and Molecular Physiology & Biophysics, Baylor College of MedicineHouston Texas
4. Labatt Family Heart Centre, The Hospital for Sick ChildrenToronto Canada
5. Division of Pediatric Cardiology University of MichiganAnn Arbor Michigan
6. Children's Heart Centre, Motol University HospitalPrague Czech Republic
7. Division of Cardiology, Phoenix Children's HospitalPhoenix Arizona