Technique for reoperative median sternotomy in the presence of a patent left internal mammary artery graft.

Damage to a patent left internal mammary artery (IMA) graft during reoperation can be catastrophic. An organized approach to reenter the mediastinum in the presence of a functioning left IMA graft is described. The sternum is opened using an oscillating saw to carefully divide the anterior and posterior tables. The right side is then dissected out first, exposing the aorta and right atrium. After placing pursestring sutures for cannulation, attention is turned to the left side. An IMA retractor is used to elevated the left edge of the sternum in incremental stages. The dissection is begun at the inferior end of the sternum, exposing the distal anastomosis first and then dissecting superiorly anterior to the IMA. A Doppler flow detector probe is used to assist in locating the artery in the adhesions.