[1] Harvard Univ, Sch Med, TIMI Study Grp, Boston, MA 02115 USA
[2] Harvard Univ, Sch Med, Div Cardiovasc, Boston, MA 02115 USA
[3] Harvard Univ, Beth Israel Deaconess Med Ctr, Sch Med, Dept Med, Boston, MA 02115 USA
[4] Harvard Univ, Brigham & Womens Hosp, Sch Med, Div Cardiovasc, Boston, MA 02115 USA