Abstract
The internal thoracic artery has a patency rate of 85%-95% at 10-15 years post coronary artery bypass graft surgery. Development of total occlusion of the internal thoracic artery within a short period (< 6 months) after the surgery is exceedingly rare. However, competitive flow between the native vessel and the conduit internal thoracic artery, or competitive flow between the 2 conduit internal thoracic arteries in a multiple arterial grafting procedure can jeopardize 1 of the 2 conduit internal thoracic arteries. We report the cases of 2 patients who had bilateral internal thoracic artery grafts, with total occlusion of 1 of the 2 grafts within a short period (6 months) after successful coronary artery bypass graft surgery.