Formation of fistulous connection between internal mammary graft and pulmonary vasculature after coronary artery bypass graft (CABG) is a rare event, which can result in recurrence of symptoms ranging from stable angina to myocardial infarction related to coronary steal. We hereby report a case of a 56-year-old man who was detected to have such a fistulous communication leading to coronary steal as the cause of effort angina 3 years after CABG. Coronary angioplasty and stenting of left anterior descending artery resulted in resolution of symptoms. Native vessel percutaneous coronary intervention as a treatment strategy for internal mammary artery to pulmonary artery fistula has not been reported previously.