1. Division of Cardiovascular Surgery, Hospital of the University of Pennsylvania, Philadelphia (N.D.D., J.E.B.).
2. Penn Cardiovascular Outcomes, Quality, and Evaluative Research Center, Leonard Davis Institute of Health Economics, Philadelphia, PA (N.D.D., J.E.B.).
3. Duke Clinical Research Institute, Duke University, Durham, NC (S.M.O., S.V., P.M.).
4. St Francis Hospital, Roslyn, NY (D.J.C.).
5. Cardiovascular Research Foundation, New York (D.J.C.).
6. Division of Cardiology, Department of Medicine, University of Colorado School of Medicine, Aurora (J.C.).
7. Department of Cardiovascular Medicine, Saint Luke’s Mid America Heart Institute, Kansas City, MO (S.V.A.).
8. Section of Cardiovascular Medicine, Yale School of Medicine, New Haven, CT (J.K.F.).
9. Department of Surgery, Piedmont Hospital, Atlanta, GA (V.H.T.).
10. Department of Medicine, Columbia University, New York (A.J.K.).
11. Division of Cardiology, Henry Ford Hospital, Detroit, MI (B.O.).
12. Division of Cardiac Surgery and Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston (D.M.S.).
13. Department of Cardiovascular and Thoracic Surgery, West Virginia University, Morgantown (V.B.).