1. From the Department of Cardiology, the Heart Centre, Rigshospitalet and University of Copenhagen, Denmark (M.J.A., M.E., A.A., F.G., C.H., L.K.,S.B., J.E.M.); the Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Rochester, MN (B.A.B.); and the Department of Biostatistics, University of Copenhagen, Denmark (L.T.S.).