1. Division of Cardiology, Hospital of the University of Pennsylvania, Philadelphia, PA
2. Division of Cardiology, Department of Medicine, University of California Los Angeles, Los Angeles, CA
3. Department of Biostatistics and Bioinformatics, Duke University, Durham, NC
4. Duke Clinical Research Institute, Duke University Medical Center, Durham, NC
5. Veterans Affairs Health System, Palo Alto, CA
6. Division of Cardiovascular Medicine and Cardiovascular Institute, Stanford University, Stanford, CA
7. Division of Cardiology, Northwestern University, Chicago, IL
8. Brigham and Women's Hospital Heart and Vascular Center and Harvard Medical School, Boston, MA