Measurements of common femoral artery flow velocity in the evaluation of aortoiliac atherosclerosis. Comparisons between pulsatility index, pressures measurements and pulse-volume recordings.

Blood flow velocity in the common femoral artery was measured in 52 limbs of 45 patients with radiologic signs of aortoiliac atherosclerosis. Group A limbs had significant obstruction of the aortoilac segment; group B had not. 'Significant' implied a transobstruction pressure gradient of greater than or equal to 10 mmHg at rest or greater than or equal to 20 mmHg after intra-arterial injection of papaverine. Pulse-volume recording (PVR) and non-invasive measurement of the common femoral artery pressure (FAP) were also performed. Pulsatility index (PI) less than 3.9 and PVR amplitude less than 13 mm indicated significant obstruction, whereas PI greater than 5.4 and PVR amplitude greater than 20 mm were observed only in limbs without significant pressure gradient across the aortoiliac segment. PI 3.9-5.4 and PVR amplitude 13-20 mm were found in both groups. FAP and flow velocity during reactive hyperemia did not adequately distinguish the two groups, because of value overlap. In assessing the hemodynamic significance of aortoiliac obstruction, PI and PVR in the common femoral artery may be useful supplements to clinical examination, but measurement of the pressure gradient across the aortoiliac obstruction before and after vasodilation probably is most reliable.