Role of Doppler ultrasonography in determining the hemodynamic significance of aortoiliac disease.

Doppler ultrasound recordings from the common femoral artery were quantified by calculation of the pulsatility index (a number of related to the maximum oscillatory energy of the wave). To demonstrate that the index permits detection of hemodynamically significant aortoiliac stenosis, studies were carried out that led to the following conclusions: (a) in patients with aortoiliac occlusive disease and normal distal vessels, the index correlates with the ankle pressure ratio (the ratio of systolic blood pressure at the ankle to brachial systolic blood pressure) (r = 0.70); (b) the index allows distinction of subjects with significant aortoiliac disease, demonstrated arteriographically, from normal subjects; and (c) in patients with pure aortoiliac occlusive disease (no evidence of distal disease on arteriography) there is a strong correlation between the index and the percentage improvement (i.e., increase) in the ankle pressure ratio following operation (r = 0.80). When the femoral pulsatility index was greater than 5, the ankle pressure ratio did not improve following operation, but when it was 4 or less, an objective improvement in ankle pressure ratio was demonstrated.