1. From the Cardiovascular Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, Mass (M.A.C., J.A.B.); Cardiology, CardioVascular Center, University Hospital and Cardiovascular Research, Institute of Physiology, University Zürich, Switzerland (T.F.L., F.C.); and Cardiology, II Faculty of Medicine, University “La Sapienza”, Rome & IRCCS Neuromed, Pozzilli, Italy (F.C.).