1. From the Departments of Internal Medicine (J.G.T., E.O.K., J.L.C.V., J.R.C.), Radiology (J.J.C., R.S., D.R.C.), and Public Health Sciences (J.J.C., G.W.E., M.A.E., J.R.C.), and the Division of Vascular Ultrasound Research (R.T., M.F.M.), Wake Forest University School of Medicine, Winston-Salem, NC; and Novartis Pharmaceuticals Corporation (M.F.M.), East Hanover, NJ.