Revascularization of the Lower Extremity: A Non-invasive Hemodynamic Comparison of Aorto-Femoral and Femoral-Femoral Bypass

Abstract

Nine patients who underwent bilateral aorto-femoral bypass and seven patients who underwent femoral-femoral bypass were evaluated to determine the increase in ankle/ arm index (a/a index) in symptomatic extremities. All patients underwent pre- and postoperative noninvasive evaluation. There were 13 symptomatic extremities in the 9 patients undergoing aorto-femoral bypass. The mean pre-operative a/a index in the aorto-femoral group was 0.50±0.15. The mean post-operative value was 0.75±0.16 (p<0.0001). The mean pre-operative value in the femoral-femoral group was 0.39±0.30 and the mean post-operative value 0.74±0.24 (p<0.02). The increase in the postoperative a/a index was the same with femoral-femoral bypass as with aorto-femoral bypass. A decision as to whether aorto-femoral or femoral-femoral bypass should be performed should be determined by considerations other than the expected immediate hemodynamic effect. Extra-anatomic bypass has become an alternative to standard aorto-femoral bypass for lower extremity revascularization in selected patients. 1,2 There have been numerous reports which have demonstrated the clinical effectiveness of both of these procedures in relieving ischemia.3 The hemodynamic effects of aorto-femoral bypass have been extensively studied non-invasively by comparing pre- and post-operative values of the ankle/arm index (a/a index).4 We have retrospectively studied the results of both aorto-femoral and femoral-femoral bypass to determine the relative effect of each in increasing the a/a index and to determine whether aorto-femoral bypass raises the a/a index more than does the femoral-femoral bypass.