An unusual cause of recurrent angina two years after coronary artery bypass grafting: fistula between internal mammary artery graft to pulmonary vasculature.

A 55-year-old man developed recurrent angina pectoris 2 years after coronary artery bypass grafting. Cardiac catheterization demonstrated that the venous grafts were patent, but selective left internal mammary angiogram showed multiple fistulous connections between the internal mammary artery and the pulmonary vasculature of the left upper lobe. After surgical correction of the fistula, the angina resolved. Only three previous cases of acquired internal mammary artery graft fistulas draining to the pulmonary vasculature have been described. The etiology, clinical presentation, and management of an internal mammary artery fistula to the pulmonary vasculature are discussed.