PURPOSE: The deep inferior epigastric perforator (DIEP) flap has become the most commonly performed method of autologous breast reconstruction in the United States. However, occasionally poor perforator anatomy or quality in the deep system can lead to inadequate perfusion, ultimately resulting in fat necrosis and an unsatisfactory reconstruction. In this setting, the superficial inferior epigastric artery (SIEA) flap can be an attractive alternative due to speed of harvest and ability to avoid the abdominal morbidity of harvesting muscle, but vessel mismatch and fat necrosis can be common complications. In aims to reduce these complications and to avoid muscle harvest, we present a novel algorithm in which 2 modifications were utilized involving the SIEA system in the setting of poor DIEP flap perforator anatomy. These include (1) a “dual-plane” flap by turbocharging the SIEA with intraflap anastomoses to cranial extent or branch of the DIE pedicle and (2) the use of the DIEA and vein as a composite interposition graft to increase pedicle length and size mismatch between the SIEA/V and the recipient chest vessels.
METHODS: Retrospective review of a prospectively maintained, 866 free flap database was performed for patients undergoing breast reconstruction at one institution with 2 surgeons from 2010 to 2017. Standard SIEA flaps were performed until 2015 in the setting of poor deep system perforators. From 2016 to 2017, a novel algorithm was utilized. If there were poor DIEP perforators and superficial vessels were present, the SIE pedicle was anastomosed to the terminal branch or superior extension of the DIE pedicle. The DIE pedicle was then anastomosed to the antegrade internal mammary vessels. If no DIEA perforators were found and the SIEA was adequate, a flap based on those vessels was performed and the DIEA/V was utilized as a composite arterial/venous interposition graft to the chest vessels. Outcomes of fat necrosis and flap loss were recorded for all flaps, and comparative statistics were conducted with 2-tailed Fisher’s exact test.
RESULTS: There were 30 standard SIEA flaps, 14 “dual-plane” flaps with a turbocharged SIEA system, 11 SIEA flaps with an interposition composite graft from the DIE pedicle, and 409 standard single pedicle hemi-abdominal DIEP flaps included in analysis. Fifteen standard SIEA flaps (50%) had fat necrosis which was significantly higher than the 59 standard DIEP flaps (14.4%) with fat necrosis (P = 0.0001). After utilization of the proposed algorithm, 2 modified SIEA flaps (8%) had fat necrosis, the reduction of which was statically significant (P = 0.001). Flap loss rates were not different between each cohort.
CONCLUSION: This retrospective cohort study suggests that utilization of a novel algorithm with 2 modifications of the superficial inferior epigastric system allowed a significant reduction in fat necrosis rates when compared to standard SIEA flaps from the same 2 surgeons. These results show that future patients, for whom we would have previously indicated for standard SIEA flaps, may have equal fat necrosis rates as standard DIEP flaps if this algorithm is utilized.