1. Duke Clinical Research Institute, Durham, North Carolina
2. University of North Carolina, Chapel Hill
3. Canadian VIGOUR Centre, University of Alberta, Edmonton, Canada
4. The LifeCare Company, Menlo Park, California
5. Cardiology Division, Massachusetts General Hospital, Boston
6. Albert Einstein College of Medicine, Bronx, New York
7. Thomas Jefferson University, Philadelphia, Pennsylvania
8. Division of Cardiovascular Sciences, National Heart, Lung, and Blood Institute, Bethesda, Maryland
9. Duke Clinical Research Institute, Durham, North Carolina9Inova Heart and Vascular Center, Fairfax, Virginia