Despite revascularization of the common femoral--profunda femoris system, many patients fail to obtain satisfactory relief from claudication or rest pain. Clinical observations were compared with objective physiological data in 54 technically successful aortoiliofemoral reconstructions for multilevel disease. Nine of 28 operations (32%) for claudication and five of 26 operations (19%) for ischemia at rest had poor results. While the average ankle pressure index (API = ankle blood pressure/arm blood pressure) rose from 0.52 +/- 0.03 (SEM) to 0.81 +/- 0.03 in limbs treated successfully for claudication, it changed insignificantly in those with an unsuccessful result (0.58 +/- 0.04 to 0.61 +/- 0.04). When ischemic symptoms were relieved, API rose from 0.23 +/- 0.04 to 0.55 +/- 0.03 but increased only from 0.22 +/- 0.09 to 0.40 +/- 0.02 in limbs with insufficient improvement. Preoperative thigh pressure index (TPI) in claudicating limbs with poor results (0.96 +/- 0.05) differed little from that in limbs with good results (0.92 +/- 0.05); nor was the TPI of ischemic limbs with poor results (0.83 +/- 0.13) significantly greater than that in limbs with good results (0.60 +/- 0.05). Neither the TPI nor the thigh to ankle pressure gradient was of value in predicting which extremities would respond poorly to aortoiliofemoral reconstruction.