1. Section of Cardiovascular Medicine, Department of Medicine, Yale School of Medicine, New Haven, CT (K.F.F., J.P.C.).
2. Richard A. and Susan F. Smith Center for Outcomes Research in Cardiology, Division of Cardiovascular Medicine, Beth Israel Deaconess Medical Center, Boston, MA (K.F.F., H.T., J.B.S., C.S., E.A.S., C.M.G., R.W.Y.).
3. Baim Institute for Clinical Research, Boston, MA (Y.S., L.M., C.M.G., R.W.Y.).
4. Cardiology Division, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston (N.M.B., R.W.Y.).
5. Medtronic, Minneapolis, MN (L.M.).