1. Heart Center, Massachusetts General Hospital, 55 Fruit Street, Yawkey 5B, Boston, MA, 02114, USA
2. Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, USA
3. Saint Luke's Hospital, 4401 Wornall Road, Kansas City, MO 64111, USA
4. Heart Center, Arnold Palmer Hospital for Children, 1222 South Orange Avenue, Orlando, FL 32806, USA
5. Ahmanson/UCLA Adult Congenital Heart Disease Center, 100 Medical Plaza, Los Angeles, CA 90095, USA