1. The Heart Institute, Cincinnati Children's Hospital Medical Center; Cincinnati OH USA
2. The Cardiac Center at the Children's Hospital of Philadelphia; Philadelphia PA USA
3. Department of Cardiology; Boston Children's Hospital; Boston MA USA
4. The Congenital Heart Center at C.S. Mott Children's Hospital; Ann Arbor MI USA
5. Labatt Family Heart Center, The Hospital for Sick Children; Toronto ON Canada
6. Department of Biostatistics, Mailman School of Public Health; Columbia University; New York NY USA
7. Division of Cardiology, Department of Pediatrics; Columbia University Medical Center; New York NY USA