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Using the Retrograde Internal Mammary System for Stacked Perforator Flap Breast Reconstruction: 71 Breast Reconstructions in 53 Consecutive Patients.

BACKGROUND
Abdominal tissue is the preferred donor source for autologous breast reconstruction, but in select patients with inadequate tissue, additional volume must be recruited to achieve optimal outcomes. Stacked flaps are an effective approach in these cases, but can be limited by the need for adequate recipient vessels. This study reports outcomes for the use of the retrograde internal mammary system for stacked flap breast reconstruction in a large number of consecutive patients.


METHODS
Fifty-three patients underwent stacked autologous tissue breast reconstruction with a total of 142 free flaps. Thirty patients underwent unilateral stacked DIEP reconstruction, 5 had unilateral stacked PAP reconstruction, 1 had bilateral stacked DIEP/SGAP reconstruction, and 17 underwent bilateral stacked DIEP/PAP reconstruction. In all cases the antegrade and retrograde internal mammary vessels were used for anastomoses. In situ manometry studies were also conducted comparing the retrograde internal mammary (RIM) arteries in 10 patients to the corresponding systemic pressures.


RESULTS
There were 3 total flap losses (97.9 percent flap survival rate), 2 partial flap losses, 4 re-explorations for venous congestion, and 3 patients had operable fat necrosis. The mean weight of the stacked flaps for each reconstructed breast was 622.8 grams. The RIM mean arterial pressures (MAP) were on average 76.6 percent of the systemic MAP.


CONCLUSION
The results demonstrate that the RIM system is capable of independently supporting free tissue transfer. These vessels provide for convenient dissection and improved efficiency of these cases with successful post-surgical outcomes.