The innominate steal.
D016122:Brachiocephalic Trunk / Q000000981:diagnostic imaging; D002339:Carotid Arteries / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D006801:Humans; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012039:Regional Blood Flow; D012212:Rheology; D013349:Subclavian Steal Syndrome / Q000175:diagnosis; D014652:Vascular Diseases / Q000000981:diagnostic imaging*; D014711:Vertebral Artery / Q000000981:diagnostic imaging