From the Research
To raise a superiorly-based rectus muscle flap after internal mammary artery (IMA) harvest for cardiac surgery, careful dissection and preservation of the superior epigastric artery is essential, as supported by the study published in 2001 1. This technique is crucial in maintaining the viability of the flap despite the sacrifice of the IMA. The key steps involve:
- Identifying the remaining superior epigastric vessels, which are the continuation of the internal mammary vessels below the costal margin
- Making a longitudinal incision through the anterior rectus sheath, preserving the superior vascular pedicle
- Carefully dissecting the rectus muscle from its posterior sheath while maintaining its superior attachment and blood supply
- Mobilizing the muscle inferiorly by dividing it at the desired level, typically at or below the umbilicus
- Ligate any perforating vessels during the dissection to prevent bleeding
The superior epigastric vessels should be handled delicately to avoid injury, as they are the primary blood supply to the flap after IMA harvest. This technique allows for a viable muscle flap despite the sacrifice of the IMA, as collateral circulation from the deep epigastric system and intercostal vessels can maintain adequate perfusion to the rectus muscle, as noted in the study published in 2001 1 and further supported by the concept of muscle perforator flaps 2. The flap can then be rotated to cover defects in the anterior chest wall, providing well-vascularized tissue coverage for sternal wounds or other thoracic defects. It is also worth noting that recent studies have explored alternative approaches, such as the use of intercostal artery-based pedicled vertical rectus abdominis muscle flaps 3, but the fundamental principle of preserving the superior epigastric artery remains crucial. Additionally, advancements in endoscopic IMA harvest 4 may influence the approach to raising a superiorly-based rectus muscle flap, but the core technique remains focused on careful dissection and preservation of the superior epigastric artery.