1. From the Departments of Cardiology (A.W.N., P.E.F.D., M.C., A.M.D., R.G.W.) and Anatomic Pathology (C.W.C.), Royal Children’s Hospital, Melbourne, Australia; Clinical Epidemiology and Biostatistics Unit, Murdoch Children’s Research Institute, Melbourne, Australia (P.C., J.B.C.); Departments of General Practice (P.C.) and Paediatrics (J.B.C.), University of Melbourne, Melbourne, Australia; and Department of Cardiology, Children’s Hospital Boston and Department of Pediatrics, Harvard Medical School,...