Subclavian Steal Syndrome with or without Arterial Stenosis: A Review

The subclavian-vertebral artery steal syndrome (SSS) is the hemodynamic phenomenon of blood flow reversal in the vertebral artery due to significant stenosis or occlusion of the proximal subclavian artery or the innominate artery. Occasionally, SSS is diagnosed in patients not harboring arterial stenosis. With the exception of arterial congenital malformations, the limited case reports of SSS with intact subclavian artery are attributed to dialysis arteriovenous fistulas (AVFs). Interestingly, these cases are more frequently symptomatic than those with the classical atherosclerotic SSS forms. On the other hand, the disclosure of SSS due to subclavian/innominate artery atherosclerotic stenosis, even in the absence of accompanying symptoms, should prompt a thorough cardiovascular work-up for the early detection of coexisting coronary, carotid, or peripheral artery disease. Herein, we review the incidence, clinical presentation, sonographic findings, and therapeutic interventions related to SSS with and without subclavian/innominate artery stenosis. We also review the currently available data in the literature regarding the association of SSS and dialysis AVF. In addition, we present a patient with bilateral symptomatic SSS as the result of an arteriovenous graft (AVG) that was introduced after the preexisting AVF in the contralateral arm became nonfunctional. SSS due to subclavian or innominate artery stenosis/occlusion is rarely symptomatic warranting interventional treatment. In contrast, when it is attributed to AVF, surgical correction is frequently necessary.