A case of Takayasu arteritis causing subclavian steal and presenting as syncope

The American Heart Association website defines syncope as "temporary loss of consciousness and posture." Syncope is a common presentation to the Emergency Department (ED). Although case reports of subclavian steal syndrome (SSS) from Takayasu arteritis (TA) and of TA causing syncope have been rarely reported in the literature, our MEDLINE search revealed no published description of the three entities of SSS, TA, and syncope presenting simultaneously. We then describe a case of a 48-year-old woman who presented to our ED with syncope and was found to have SSS. We describe the patient's hospital course leading to the diagnosis of TA, which is a rare form of vasculitis. Finally, we briefly discuss TA, explain the mechanism of SSS in TA, and outline the diagnostic criteria established by the American College of Rheumatology for TA.