1. The Division of Cardiology, Children's Hospital of Philadelphia, The Cardiovascular Division, University of Pennsylvania Health System, and The Cardiology Division, Philadelphia Veterans Administration Medical Center, Philadelphia, PA.
2. The Division of Cardiology, Children's Hospital of Philadelphia, The Cardiovascular Division, University of Pennsylvania Health System, and The Cardiology Division, Philadelphia Veterans Administration Medical Center, Philadelphia, PA.
3. The Division of Cardiology, Children's Hospital of Philadelphia, The Cardiovascular Division, University of Pennsylvania Health System, and The Cardiology Division, Philadelphia Veterans Administration Medical Center, Philadelphia, PA.