1. Methodist DeBakey Heart and Vascular Center, Center for Outcomes Research, Houston Methodist Research Institute, TX (S.F.N., M.A.C.-p., K.C.E.t., J.X.).
2. Department of Medicine, University of Massachusetts Medical School, Worcester (G.P.A., S.R.S.).
3. Division of Cardiology, University of California at San Francisco (T.P.A., A.B.).
4. Department of Cardiology, Leiden University Medical Center, the Netherlands (J.J.B., V.D., G. Dolci).
5. University of Medicine and Pharmacy “Carol Davila,” Euroecolab, Institute of Cardiovascular Diseases, Bucharest, Romania (C.B., B.A.P.).
6. Physiology Department, DHU Ageing-Thorax-Vessel-Blood, Henri Mondor Hospital, Assistance Publique Hôpitaux de Paris, Créteil, France (G. Derumeaux, L.E., M.P.).
7. Service de Cardiologie et Maladies Vasculaires, LTSI INSERM 1099, Universite Rennes-1, CHU Rennes, France (E.D., A.H.).
8. University of Oslo, Norway (T.E., O.A.S.).
9. Department of Advanced Biomedical Sciences, Federico II University Hospital, Naples, Italy (R.E., M.G.).
10. Department of Medical Sciences, Uppsala University, Clinical Physiology and Cardiology, Uppsala, Sweden (F.A.F.).
11. Cleveland Clinic, OH (J.G., S.C.H., A.L.K.).
12. Department of Cardiology, MedStar Heart and Vascular Institute, Washington, DC (S.A.G., R.Z.M.).
13. Division of Cardiology, Corrigan Minehan Heart Center, Massachusetts General Hospital, Harvard Medical School, Boston (J.H.).
14. University of Liège Hospital, Belgium (P.L.).
15. Universita Piemonte Orientale, Novara, Italy (P.M.).