1. From the Veterans Affairs Palo Alto Health Care System, CA (M.P.T., S.K.S., J.F., C.T.T.); Department of Medicine, Stanford University School of Medicine, CA (M.P.T.); Medtronic Cardiac Rhythm Disease Management, Mounds View, MN (P.D.Z.); San Francisco Veterans Affairs Medical Center, CA (E.K.K.); and Division of General Internal Medicine, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston (Y.C., D.E.S.).