1. Division of Cardiovascular Medicine; Vanderbilt Heart & Vascular Institute, Nashville, Tennessee
2. Division of Cardiology; Duke University Medical Center; Durham North Carolina
3. Division of Cardiology; Weill Cornell Medical College; New York New York
4. Penn Heart and Vascular Center; Perelman School of Medicine, University of Pennsylvania; Philadelphia Pennsylvania
5. Division of Cardiology; Wake Forest School of Medicine; Winstom-Salem North Carolonia
6. MedStar Washington Hospital Center; Washington DC
7. Penn State Hershey Heart and Vascular Institute; Hershey Pennsylvania
8. Emory University School of Medicine; Children's Healthcare of Atlanta; Atlanta Georgia
9. Knight Cardiovascular Institute, Department of Medicine; Oregon Health and Sciences University; Portland Oregon