1. From the Division of Cardiovascular Diseases (T.D.W., G.W.B., P.C.S., R.T.T., M.E.-S., H.I.M.), Department of Radiology (T.F.), and Division of Cardiovascular Surgery (S.J.P.), Mayo Clinic, Rochester, MN, and Department of Cardiac Imaging, Hospital Vall d'Hebron, Barcelona, Spain (A.E.).