1. Department of Medicine, Cardiovascular Division (M.C.Y., E.A.L., S.D.L., J.L.S., J.D.M., E.A.O., J.B.S.), Beth Israel Deaconess Medical Center, Boston, MA.
2. Department of Medicine, Cardiology Division, Tufts University Medical Center, Boston, MA (S.D.L).
3. Division of Cardiovascular Medicine, Richard A. and Susan F. Smith Center for Outcomes Research in Cardiology, (J.B.S.), Beth Israel Deaconess Medical Center, Boston, MA.