1. From the Department of Cardiology, Children’s Hospital, Boston, Mass (A.L.K., J.E.L., S.B.P., D.B.M., K.G., M.J.L., K.J.J.); Department of Pediatrics, Children’s Hospital of Philadelphia, Philadelphia, Pa (J.J.R.); Department of Pediatrics, Columbia University College of Physicians and Surgeons, New York, NY (W.E.H.); and Department of Pediatrics, University of Illinois, Chicago (C.E.R.). Dr Perry is now at Stanford University Medical Center, Stanford, Calif. Dr Ruiz is now at the University of...