Reoperative revascularization of a left internal mammary artery ostial stenosis.

A severe ostial stenosis of the left internal mammary artery graft was responsible for unstable angina in a patient with a previous coronary artery bypass graft. Successful revascularization of the lesion was achieved with a subclavian artery-to-left internal mammary artery bypass using a saphenous vein conduit. This procedure was performed through a left thoracotomy incision to avoid potential hazards of a redo median sternotomy.