1. Division of Cardiology, Department of Medicine, Duke University School of Medicine, Durham, NC. (H.J.W., R.J.M.)
2. Duke Clinical Research Institute, Durham, NC (H.J.W., R.J.M.).
3. Department of Internal Medicine, Section on Cardiovascular Medicine, Wake Forest School of Medicine, Winston-Salem, NC. (D.W.K., M.B.N., B.U.)
4. Department of Medicine, Thomas Jefferson University, Philadelphia, PA (D.J.W., G.R.R.).
5. Department of Neurology, Wake Forest School of Medicine, Winston-Salem, NC. (P.W.D.)
6. Departments of Medicine and Orthopaedic Surgery, Duke University School of Medicine, Durham, NC. (A.M.P.)