1. From the Section of Vascular Surgery, Dartmouth-Hitchcock Medical Center, Lebanon, NH (R.R.D.M., B.S.B., J.B.W., B.W.N., J.L.C., P.P.G.); University of Massachusetts Memorial Medical Center, Worcester (W.R., A.S.); and Yale School of Medicine, New Haven, CT (J.E.I.).