The prognostic value of the noninvasive vascular laboratory in autologous vein bypasses of the lower extremities.

A retrospective study of 34 patients with 29 autologous vein femoropopliteal and 8 femorotibial bypasses was conducted, examining the correlation of angiographic runoff and non-invasive flow determinants as prognostic indicators of early graft occlusion of lower limb bypass grafts. The followup period was 3-27 months, with a mean of 5.8 months. Graft patency and improvement in presenting symptoms were unrelated to preoperative ankle systolic pressure indices. Preoperative and postoperative flow measurements were similar in patients with patent grafts (greater than 12 months) and in those with early graft occlusion (0-6 months, p greater than .05). Preoperative pressure indices did not correlate with calf vessel runoff (p. greater than 05). The data suggest: (1) the noninvasive flow studies are not reliable predictors of future graft patency, (2) vessel runoff is not a reliable predictor of limb flow, and (3) bypass procedures in the lower extremities should not be excluded on the basis of noninvasive flow studies when indicated by other clinical parameters.