1. Division of Pediatric Cardiology, Department of Pediatrics and Child Health (N.A.S., T.F.S., T.A., J.L., G.C., R.D.D., L.S., A.J., L.J.Z.).
2. Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, United Kingdom (J.E., B.D.K.).
3. Department of Medicine, Cape Heart Institute (T.F.S., G.S., L.J.Z.).
4. Chris Barnard Division of Cardiothoracic Surgery, Department of Medicine, Faculty of Health Sciences (P.H., A.B.).
5. Cardiovascular Genetics Laboratory, Hatter Institute for Cardiovascular Research in Africa (M.V., G.S.).
6. Division of Pediatric Cardiology, Department of Pediatrics and Child Health, University of Stellenbosch, Cape Town, South Africa (J.L., B.F.).
7. Division of Cardiology, Department of Medicine, Groote Schuur Hospital, Faculty of Health Sciences (B.C., L.J.Z.).
8. MRC Genomic & Precision Medicine Research Unit, Division of Human Genetics, Dept of Pathology, Institute for Infectious Diseases and Molecular Medicine, University of Cape Town, Cape Town, South Africa (R.R.).
9. South African Medical Research Council, Cape Town (L.J.Z.).