1. Ward Family Heart Center, Children's Mercy Kansas City Kansas City MO USA
2. Prenatal Cardiology Program, Children's National Hospital George Washington University School of Medicine Washington DC USA
3. The Fetal Heart Program at the Cardiac Center at The Children's Hospital of Philadelphia Philadelphia PA USA
4. Division of Pediatric Cardiology, Department of Pediatrics University of California San Francisco San Francisco CA USA
5. Division of Pediatric Cardiology, Ann and Robert H Lurie Children's Hospital of Chicago Northwestern University Feinberg School of Medicine Chicago IL USA