The evaluation of asymptomatic arterial occlusive disease of the legs using an exercise test

The Doppler-derived ankle pressure index (API) is a useful indicator of the necessity for peripheral vascular reconstruction of the lower extremities. But the API at rest dose not reflect the functional capacity of leg circulation, especially in the early stage of disease. Therefore, an asymptomatic but hemodynamically significant lesion in one leg is sometimes missed by pressure measurement at rest when there is a severe lesion with symptoms in the other leg. In this study, the API not only at rest but also after exercise was measured in twenty normal subjects and thirty-two patients with angiographically proven arteriosclerosis obliterans. About 60% of the patients had unilateral symptoms, although they had significant disease bilaterally. The API after exercise proved to be more sensitive than the API at rest and may be useful in assessing asymptomatic legs of such patients and determining their surgical indication.