Anomalous origin of the left thyrocervical trunk as a cause of residual pain after myocardial revascularization with internal mammary artery.

A patient with successful implantation of an internal mammary artery graft in the left anterior descending coronary artery complained of residual but different anginal pain after operation. Ischemia was demonstrated during a manual stress test. Angiography revealed anomalous origin of the thyrocervical trunk from the internal mammary artery. Angina and ischemia disappeared after the trunk was ligated.