1. From the Division of Cardiovascular Medicine (A.M.W., E.K., R.K.H., N.N., B.N., K.R.B., J.P.C.), Stanford University, Stanford, Calif; Ciphergen Biosystems Inc (X.-Y.M., F.Z., E.T.F.), Fremont, Calif; and Zena and Michael A Wiener Cardiovascular Institute (J.W.O.), Mount Sinai Medical Center, New York, NY.