1. Valve Science Center (A.O., K.R.T., E.W.-K., L.I.S., M.R.B., H.K., C.W., A.P., J.R.L., P.S., V.N.B.), Minneapolis Heart Institute Foundation, MN.
2. Cardiovascular Imaging Research Center and Core Lab (M.F., J.L.C.), Minneapolis Heart Institute Foundation, MN.
3. Michael E. DeBakey VA Medical Center, Baylor College of Medicine, Houston, TX (S.Z.).
4. Minneapolis Heart Institute at Abbott Northwestern Hospital, MN (J.R.L., J.L.C., P.S., V.N.B.).