1. Division of Pediatric Cardiology, Department of Pediatrics, University of Arkansas for Medical Sciences and Arkansas Children’s Research Institute, Little Rock (S.T.D.).
2. Division of Pediatric Cardiology, Department of Pediatrics, Rady Children’s Hospital, University of California, San Diego, La Jolla (S.T.D., K.S., B.M.G., H.E.-S.).
3. Division of Pediatric Cardiology, University of Iowa Stead Family Children’s Hospital, Iowa City (K.S., O.A., B.M.N.).
4. Division of Pediatric Cardiology, Department of Pediatrics, Children’s Medical Center, University of Texas Southwestern Medical Center, Dallas (A.M., S.R.V.R.).