Characteristics and outcomes of primary interposition vascular grafts in free flap breast reconstruction.

[INTRODUCTION] There is paucity of data on primary interposition vascular grafts (IVG) use in microsurgery. Our study examines the characteristics, indications and outcomes of IVG in free flap breast reconstruction.

[METHODS] All cases of breast reconstruction with free flaps between January 2013 and June 2018 were examined and cases with primary IVG were included. Data were collected on patient, flap and graft characteristics, indications and outcomes.

[RESULTS] A total of 76 IVG, specifically 65 vein grafts and 11 arterial grafts, were used for 49 (of 1547) flaps in 48 (of 1346) cases. Of these, 52 grafts were primarily used to lengthen the pedicle and aid flap inset and 24 grafts to augment venous flow; 49 grafts were harvested from the flap harvest site, 7 from the anastomosis recipient site and 20 from a separate site. Of the total, 16.7% (8/49 flaps) required salvage procedures - seven cases for venous congestion and one for ischaemic compromise - in comparison to 4.3% in cases without IVG (65/1498) (p<0.0001). Out of 49 IVG flaps, three (6.1%) failed in comparison to 1.7% (26/1498), where IVG flaps were not used (p<0.05). Two were transverse upper gracilis flaps with vessel calibre mismatch, and one lumbar artery perforator (LAP) flap with past infected implant and failed deep inferior epigastric artery (DIEP).

[CONCLUSION] We present the largest number of primary vascular grafts for free flap breast reconstruction in the literature. Primary IVG were used for at-risk flaps and had a success rate of 93.9%. This shows that IVG are a viable option to prevent venous congestion and lengthen the pedicle to aid inset and shaping; they are associated with higher complication rates bearing in mind the high-risk profile of the flaps these are used for.