1. From the Duke Clinical Research Institute, Durham, NC (J.P.P., A.F.H., D.D., K.L.T., E.D.P.); MetroHealth Medical Center, Cleveland, Ohio (W.R.L.); Baylor Heart and Vascular Institute, Dallas, Tex (C.W.Y.); and University of California Los Angeles Medical Center, Los Angeles (G.C.F.).