1. Mayo Clinic, Rochester, Minnesota
2. Duke Clinical Research Institute, Durham, North Carolina
3. Brigham and Women’s Hospital, Boston, Massachusetts
4. Massachusetts General Hospital, Boston
5. Hennepin County Medical Center, Minneapolis, Minnesota
6. University of Utah, Salt Lake City
7. University of Vermont, Burlington
8. Tufts Medical Center, Boston, Massachusetts
9. University of Montreal and Montreal Heart Institute, Montreal, Canada
10. Cleveland Clinic, Cleveland, Ohio
11. Emory University, Atlanta, Georgia
12. Michael E. DeBakey VA Medical Center and Baylor College of Medicine, Houston, Texas
13. Duke University Medical Center and Duke Heart Center, Durham, North Carolina
14. Thomas Jefferson University, Philadelphia, Pennsylvania
15. University of Pennsylvania, Philadelphia
16. Morehouse School of Medicine, Atlanta, Georgia
17. Washington University School of Medicine, St Louis, Missouri
18. National Heart, Lung, and Blood Institute, Bethesda, Maryland