Interpositional Lateral Thoracic Vein Graft for DIEP Flap Salvage in Setting of Superficial Venous System Dominance.

Sir:

The deep inferior epigastric artery perforator free flap is the workhorse for perforator-based breast reconstruction due to decreased morbidity and overall hospital costs compared with other flaps.[1] The primary vascular drainage of the lower abdomen is through the superficial venous system, which is connected via perforating vessels to secondary deep inferior epigastric veins (DIEV) that are more commonly utilized during reconstruction. However, venous congestion requiring intraoperative salvage has been reported in 3–13% of cases, with up to 70% attributed to complete superficial venous system dominance.[2,3] For this reason, preemptive planning and preservation of at least 5–6 cm of superficial inferior epigastric vein (SIEV) is recommended.

Numerous operative strategies that incorporate the SIEV have been proposed to substitute or augment outflow, including supercharging to deep-system or alternative venous recipients (i.e., retrograde limb/branch of internal mammary, thoracodorsal, or extrathoracic veins). In cases where the SIEV has been inadequately preserved or has insufficient length to facilitate direct anastomosis, an interpositional vein graft may be required. Although several options exist, harvesting distant grafts necessitates additional consent, increased operative time, and donor-site morbidity. A convenient solution to these challenges often arises during immediate reconstruction after mastectomy with lymph node dissection. In this scenario, the exposed lateral thoracic vein (LTV) can be rapidly and safely harvested from the same operative field as the mastectomy for use as an interpositional graft to relieve venous congestion.[4]

The LTV, usually a branch of the axillary vein, can be found coursing along the pectoralis minor muscle, laterally, and pectoralis major, inferiorly.[5] This vessel is comparable in caliber with both the SIEV and DIEV (i.e., 1–3 mm diameter) and can provide up to 8 cm of additional length for grafting. In cases where the LTV has been injured or ablated during mastectomy, the thoracodorsal vein can be identified just posterior, along the anterolateral border of the latissimus dorsi, and serves as a viable alternative (i.e., 2–3 mm diameter, 8 cm length) for grafting.[5] Intraflap dissection of the SIEV for 1–2 cm may be required to lengthen the cuff available for graft anastomosis (Fig. 1). It is our preference to connect the SIEV–LTV graft end-to-end along the original DIEV–internal mammary vein axis to maintain laminar outflow and minimize flap tethering during inset. Distal interconnections between the DIEVs are often present and should be preserved to shunt additional outflow through the deep venous system (Fig. 2).[3]

Fig. 1.

A 45-year-old woman with left breast cancer underwent unilateral skin-sparing mastectomy and left axillary dissection, with immediate deep inferior epigastric artery perforator free flap reconstruction. Intraoperatively, global flap congestion was noted before pedicle ligation. The remnant SIEV was inadequately preserved to facilitate direct anastomosis. Exploration of the lateral breast pocket revealed an intact and exposed LTV. A 4-cm vein graft was harvested and interposed between the remnant SIEV and a proximal segment of the DIEV. Intraflap dissection provided an additional 2 cm cuff of SIEV for graft anastomosis. Immediate relief of congestion was noted in situ, and the SEIV–LTV–DIEV construct was connected in series to the internal mammary vein without complication.

Fig. 2.

Illustration demonstrating the orientation of the lateral thoracic interpositional vein graft, which is connected in series between the superficial inferior epigastric and the DIEVs. Distal interconnections between the 2 deep veins are preserved to maintain outflow from the deep venous system.

Challenges associated with LTV/thoracodorsal vein grafts include increased time of microvascular work and their preclusion in future reconstructions. Therefore, we prefer the LTV as our first-line option for interpositional vein grafting within the chest, as this preserves the latissimus dorsi as a potential salvage alternative in cases of total or partial flap loss. Advantageously, if any lymph node dissection has been performed, the LTV is likely exposed. Thus, this technique offers an optimal solution that minimizes dissection time and donor-site morbidity in cases where SIEV length is inadequate for direct anastomosis.