1. From the Division of Cardiology (D.O.W.), Rhode Island Hospital, Brown University, Providence, RI; the Department of Epidemiology (R.H., W.Y., S.F.K., H.A.V., K.M.D.), University of Pittsburgh, Pittsburgh; Lankenau Hospital (P.C.), Philadelphia, Pa; Montreal Heart Institute (M.G.B.), Montreal, Quebec, Canada; Cardiovascular Medical Associates (M.A-B.), Houston, Tex; Providence/St. Vincent Hospitals (P.C.B.), Portland, Ore; University of Pittsburgh Medical Center (H.C.), Pittsburgh, Pa; Medical...