1. From the Cardiology Division of the Brigham and Women's Hospital (P.L.), Harvard Medical School, Boston
2. Laboratory Clinical Chemistry, Division LAB, University Medical Center Utrecht, The Netherlands (G.P.)
3. Department of Cardiovascular and Thoracic Sciences, F. Policlinico Gemelli – IRCCS, Università Cattolica del Sacro Cuore, Roma, Italy (F.C.).
4. Massachusetts General Hospital (I.-K.J.), Harvard Medical School, Boston