1. The Lillie Frank Abercrombie Section of CardiologyTexas Children's Hospital, Baylor College of Medicine Houston Texas
2. The Heart Institute, Cincinnati Children's Hospital Medical CenterUniversity of Cincinnati College of Medicine Cincinnati Ohio
3. The Cardiac Center at the Children's Hospital of PhiladelphiaUniversity of Pennsylvania School of Medicine Philadelphia Pennsylvania
4. Children's Healthcare of AtlantaEmory University School of Medicine Atlanta Georgia