Internal thoracic artery side branch ligation for post coronary surgery ischemia.

Two cases of internal thoracic artery side-branch ligation in patients with recurrent angina after coronary bypass are reported with long-term follow-up. Ligation was performed with clips via a left thoracotomy. Treadmill stress testing after 3 and 4 years did not provoke any myocardial ischemia. These findings suggest that an unligated side-branch can produce a steal phenomenon.