Retrograde internal mammary artery flow and resistant angina pectoris: Clues to the coronary‐subclavian steal syndrome

A 68‐year‐old woman with persistent angina immediately following coronary bypass surgery using a left internal mammary artery graft was diagnosed as having “coronarysubclavian steal syndrome” 13 years after operation. We outline clinical and angiographic clues that will aid in the identification and diagnosis of this syndrome, which may become more common with the increased use of the mammary artery as a coronary bypass conduit.