1. Department of Medicine, Massachusetts General Hospital, Boston
2. Brigham and Women’s Hospital Heart and Vascular Center, Harvard Medical School, Boston, Massachusetts
3. Department of Internal Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts
4. Division of Cardiology, Massachusetts General Hospital and Baim Institute for Clinical Research, Boston
5. Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland