Rectus abdominis muscle flaps used successfully for median sternotomy wounds after ipsilateral internal mammary artery ligation.

Use of the rectus abdominis muscle for reconstruction based on its superior blood supply has been said by some to be contraindicated if the ipsilateral internal mammary artery (IMA) has been divided for reasons such as coronary artery bypass grafting. The authors describe 5 patients in whom either both IMAs were used for coronary revascularization or in whom there was a contralateral subcostal incision, and they were thus compelled to perform sternal reconstruction using at least one rectus abdominis muscle ipsilateral to prior IMA ligation. In all patients the muscle flap was used to reconstruct an open median sternotomy wound successfully. An injection study as well as a fresh cadaveric dissection revealed rich collateral circulation to the superior epigastric vascular pedicle through the musculophrenic artery as well as through the lower intercostal arteries. This case report and the series of 5 patients indicate that if elevation of the rectus muscle and division of the lateral segmental vessels is done only up to the costal margin, one can reliably maintain a viable rectus muscle flap, even in the face of prior ipsilateral IMA ligation. This enables useful reconstruction to the lower half of a sternal wound using the rectus abdominis muscle, requiring a pectoralis major muscle flap for the superior part of the wound.