1. Department of Cardiology and
2. Department of Pediatrics, Harvard Medical School, Harvard University, Boston, Massachusetts;
3. Department of Pediatrics, School of Medicine and Rady Children’s Hospital, University of California, San Diego, La Jolla, California; and
4. Department of Cardiology, Centre Hospitalier Universitaire Sainte-Justine, Montreal University, Montreal, Canada
5. Division of Immunology, Boston Children’s Hospital, Boston, Massachusetts;