Recurrent Subclavian Steal Syndrome: A Novel Case of Vasculopathy.

Subclavian steal syndrome (SSS) refers to the phenomenon of retrograde flow in an ipsilateral branch of the subclavian artery due to hemodynamically significant stenosis or occlusion of the ipsilateral proximal subclavian artery. While SSS is usually asymptomatic, it can manifest as vertebrobasilar insufficiency (VBI), ischemia of the affected extremity, or cardiac angina when an internal mammary artery (IMA) is used as a bypass graft. The underlying etiology is most often atherosclerosis but can include Takayasu arteritis, thoracic outlet syndrome, cervical rib, and stenosis secondary to surgical repair of aortic coarctation or tetralogy of Fallot.