1. Duke Clinical Research Institute, Durham, NC (E.C.O., D.N.H., L.E.T., E.D.P., J.P.P.)
2. UCLA Division of Cardiology, Los Angeles, CA (G.C.F.)
3. University of Colorado Denver School of Medicine (L.A.A.)
4. Mayo Clinic, Rochester, MN (B.J.G.)
5. Jefferson Medical College, Wynnewood, PA (P.R.K., M.D.E.)
6. Harvard Medical School and Massachusetts General Hospital, Boston (D.E.S.)
7. Penn State Hershey Heart and Vascular Institute, Hershey (G.V.N.)
8. Hofstra North Shore/LIJ School of Medicine, Hempstead, NY (J.E.A.)
9. University of Missouri-Kansas City School of Medicine (P.S.C.)
10. Stanford University School of Medicine, CA (K.W.M.)
11. Kaiser Permanente, Oakland, CA (A.S.G.)
12. Yale School of Medicine, New Haven, CT (J.V.F.)
13. Columbia University, Division of Cardiology, New York, NY (J.A.R.)
14. Boston University School of Medicine, MA (E.M.H.).