1. From the Sections of Cardiology (S.S., C.J.A., K.S., M.A.Q., W.L.W., W.A.Z.) and Cardiovascular Sciences (N.G.F.), Department of Medicine, and the Department of Surgery (R.E., G.V.L., G.M.L., M.J.R.), Baylor College of Medicine and the DeBakey Heart Center, Houston, Tex.