Ultrasound and angiographic assessment of collateral circulation in bilateral steal syndrome

Abstract

Background. The purpose of this work was the assessment of haemodynamics of blood pressure in bilateral subclavian steal syndrome based on results of Doppler and angiographic examinations.
Material and methods. The examinations were performed in three symptomatic patients suffering from bilateral subclavian steal syndrome. Doppler examination, including extracranial artery flow measurement, was made with the use of a 5-9 MHz linear head. Examination of the basilar artery through the great foramen as well as of the posterior communicating arteries and the posterior cerebral arteries through the parietal window was made with the use of a 2.5 MHz sector head. Development of steal was assessed in 3-stage scale. Angiographic examinations were made using the Seldinger method, and providing contrast medium to the ascending aorta and the aortic arch branch.
Results. Significant haemodynamic disorders, along with a total flow reversal in the homonymous vertebral artery in the case of subclavian artery occlusion, and along with a bidirectional flow in the vertebral artery in the case of subclavian artery stenosis, were found respectively. Each time, well-developed collateral circulation from the external carotid arteries through the occipital arteries or through the superior thyroid arteries was observed. Moreover, the presence of tiny collateral vessels directly from the aorta was also found.
Conclusions. Doppler arterial examination is a valuable type of examination for diagnosing and assessing steal syndrome. In symptomatic patients, diagnostics must be indispensably accompanied by angiographic examinations.