1. From the Department of Medical Sciences, Cardiology (S.K.J., B.L., L.W.) and Clinical Chemistry (A.S., M.S., P.V.), University of Uppsala, Uppsala, Sweden; the Department of Medicine (P.A.), University of Alberta, Edmonton, Canada; Centocor (E.S.B.), Malvern, Pa; Duke University Clinical Research Institute (R.C.), Durham, NC; Cleveland Clinic of Medicine, Case Western Reserve University (E.J.T.), Cleveland, Ohio; and the Thoraxcenter (M.L.S.), Erasmus Medical Center Rotterdam, the Netherlands.