1. From the Cardiology Division, Massachusetts General Hospital, Harvard Medical School, Boston (G.D.L., M.J.S., R.M.); Cardiovascular Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA (M.M.G.); Duke Clinical Research Institute, Durham, NC (K.J.A., A.F.H.); Division of Cardiovascular Sciences, National Heart, Lung and Blood Institute, Bethesda, MD (M.R.S.); and Harvard Medical School, Boston, MA (E.B.).