To the Editor.—The article by Quiñones-Baldrich and colleagues1 was brought to my attention, shortly after publication, by the sales representative of one of the companies distributing polytetrafluoroethylene grafts in our area. He was using this article as the basis for his rationale in trying to convince me to abandon my usual policy of using autogenous saphenous vein for femoropopliteal bypasses. "As shown here, PTFE grafts should be selected as the first choice arterial substitute" was his opening line. This article may be appealing at first glance, but careful evaluation discloses several significant deficiencies.
Over a period of four years, the authors performed 142 femoropopliteal revascularizations using polytetrafluoroethylene grafts. Only 63 of these patients were included in the study, they were not randomized, and their follow-up time periods clearly show that they were not consecutive cases either. The only explanation given for their selection was that the decision to