1. From the Cardiac Ultrasound Lab, Massachusetts General Hospital, Harvard Medical School, Boston, MA (M.C.P.N., T.C.T., M.D.H., A.E.W., J.H.); School of Medicine, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil (M.C.P.N.); Division of Cardiology, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA (S.E., R.d.L., R.M., I.C.-G., I.I., I.F.P.); and Massachusetts General Hospital Biostatistics Center, Harvard Medical School, Boston, MA (H.Z.).