Clinical and hemodynamic significance of innominate artery lesions evaluated by ultrasonography and digital angiography.

To determine the hemodynamic and clinical consequences of an atherosclerotic obstructive lesion of the innominate artery on the cerebral circulation, 20 patients with an innominate artery lesion underwent neurologic examination and ultrasonic duplex scanning before and after right arm exercise. The patients were divided into two groups: Group 1, 12 patients with 40-80% stenosis and Group 2, eight patients with 80-100% stenosis. A significant difference between the groups was noted in both the hemodynamic and clinical manifestations. All 12 Group 1 patients compensated for the increased demand for blood of the right arm through the innominate artery itself, and only one showed symptoms of vertebrobasilar insufficiency associated with right arm exercise. In all eight Group 2 patients, compensation through the innominate artery failed; six (75%) showed symptoms of vertebrobasilar insufficiency after exercise. Dynamic duplex scanning is well suited to investigate stenotic lesions of the innominate artery, the effects of arm exercise on the development of cerebral symptoms, and the source of blood flow to the arm. Dynamic duplex scanning proved to be useful in selecting patients who may be candidates for direct arterial surgery.