Use of Composite Arterial and Venous Grafts in Microsurgical Breast Reconstruction: Technical Challenges and Lessons Learned

Multi-Flap Microsurgical Autologous Breast Reconstruction

Microsurgical autologous breast reconstruction (MABR) remains the gold standard technique of breast reconstruction, providing a durable, natural, and aesthetically pleasing result. However, some patients may not be candidates for a traditional deep inferior epigastric perforator (DIEP) flap, either due to abdominal tissue paucity, the need for higher-volume reconstruction, or prior surgical procedures. In these patients, alternative flaps must be considered to achieve the optimal result. Such configurations include the conjoined (or double pedicle) DIEP flap, and alternative flaps such as the lumbar artery perforator (LAP) and profunda artery perforator (PAP) flaps, which can be combined in a stacked fashion. By combining multiple flaps in a conjoined or stacked fashion, breast reconstruction can be optimized to fulfill the three critical components of breast reconstruction in restoring the skin envelope, breast footprint, and conus shape. When harvesting multiple flaps, the surgical sequence of events must be meticulously planned to ensure an efficient and successful operation. Preoperative imaging can aid the surgeon in identifying the ideal perforator, assess for side branches for possible intra-flap anastomoses, expedite the operative time, and decrease intraoperative complications. Reconstructive surgeons should be familiar with the variety of configurations with conjoined and/or stacked flaps to address patient-specific reconstructive needs.

A Systematic Review of Microsurgical Pedicle Lengthening in Free Tissue Transfer

INTRODUCTION

Traumatic injuries that require free tissue flaps for reconstruction may require vascular pedicle extension between the flap and recipient vessels to form a clear anastomosis. Currently, a variety of techniques are used, each with their own potential benefits and harms. In addition, reports in the literature conflict on the reliability of pedicle extensions of vessels in free flap (FF) surgery. The objective of this study is to systematically assess the available literature about outcomes of pedicle extensions in FF reconstruction.

METHODS

A comprehensive search was performed for relevant studies published up to January 2020. Study quality was assessed using the Cochrane Collaboration risk of bias assessment tool and a set of predetermined parameters was extracted by 2 investigators independently for further analysis. The literature review yielded 49 studies investigating pedicled extension of FF. Studies meeting inclusion criteria underwent data extraction focusing on demographics, conduit type, microsurgical technique, and postoperative outcomes.

RESULTS

The search yielded 22 retrospective studies totaling 855 procedures from 2007 to 2018 in which 159 complications (17.1%) were reported in patients aged between 39 and 78 years. Overall heterogeneity of articles included in this study was high. Free flap failure and thrombosis were the 2 most prevalent major complications noted: vein graft extension technique had the highest rate of flap failure (11%) in comparison with the arterial graft (9%) and arteriovenous loops (8%). Arteriovenous loops had a rate of thrombosis of 5% versus 6% in arterial grafts and 8% in venous grafts. Bone flaps maintained the highest overall complication rates per tissue type at 21%. The overall success rate of pedicle extensions in FFs was 91%. Arteriovenous loop extension resulted in a 63% decrease in the odds of vascular thrombosis and a 27% decrease in the odds of FF failure when compared with venous graft extensions (P < 0.05). Arterial graft extension resulted in a 25% decrease in the odds of venous thrombosis and a 19% decrease in the odds of FF failure when compared with venous graft extensions (P < 0.05).

CONCLUSIONS

This systematic review strongly suggests that pedicle extensions of the FF in a high-risk complex setting are a practical and effective option. There may be a benefit to using arterial versus venous conduits, although further examination is warranted given the small number of reconstructions reported in the literature.

Modern Approaches to Alternative Flap-Based Breast Reconstruction: Stacked Flaps

Total breast reconstruction following mastectomy requires multiple components to achieve an aesthetic result. In some situations, significant skin is required to provide the needed surface area to allow breast projection and breast ptosis. Additionally, ample volume is required to reconstruct all breast quadrants and provide sufficient projection. All aspects of the breast base must be filled to achieve total breast reconstruction. In very specific circumstances, multiple flaps are employed to accomplish this level of uncompromised aesthetic breast reconstruction. The abdomen, thigh, lumbar region, and buttock can all be used in some combination, as needed, to perform both unilateral and bilateral breast reconstruction. The ultimate goal is to provide superior aesthetic results in both the recipient breast and the donor site while maintaining a very low level of long-term morbidity.

The Value of BMI for Breast Reconstructions with the SIEA Flaps: Predicting the Ideal Intercostal Plane for the End-to-End Microvascular Anastomosis and the Possibility of Utilizing the TDA as a Salvage Recipient Choice

BACKGROUND

The superficial inferior epigastric artery (SIEA) diameter and the matching degree between the donor and the recipient arteries in terms of diameter are key factors affecting the outcome of the procedure in breast reconstructions with the SIEA flaps. A diameter of the SIEA ≥ 1.5 mm and a matching degree ≥ 1:2 (50%) of the diameters of the donor and the recipient arteries are recognized standards for the SIEA and the internal mammary artery (IMA) to achieve an end-to-end anastomosis. However, further refinements of the population characteristics and the ideal microscopic anastomosis intercostal planes are currently lacking for the criteria.

METHODS

In this study, based on 20 sides of hemiabdomen with computed tomography angiography (CTA) data suggesting the presence of the SIEA, we analysed the diameters of the donor and the recipient arteries as well as their matching degrees. The correlations between the parameters above and body mass index (BMI) were assessed. Based on the lower bounds of the 95% confidence intervals of the matching degrees and the two critical nodes of 50% and 67%, we theoretically evaluated the possibility of an end-to-end anastomosis of the SIEA and the IMA at different levels of BMIs and intercostal spaces, and predicted the possible intraoperative management measures for the SIEA.

RESULTS

The SIEA diameter, the thoracodorsal artery (TDA) diameter, and the diameters of the IMA at the 2nd to the 5th intercostal levels were positively correlated with the BMI (p < 0.05). A value of BMI ≥ 24 kg/m² could indirectly reflect the application premise of the diameter of the SIEA ≥ 1.5 mm. The matching degrees of the SIEA with the TDA or the IMA at the 2nd to the 5th intercostal level were linearly and positively correlated with the BMI (p < 0.001). Based on the confidence interval analysis, we predicted different management techniques that might be needed intraoperatively for the SIEA at different BMI levels, when the SIEA and the IMA or the TDA were to be anastomosed in an end-to-end way.

CONCLUSION

For patients with preoperative CTA data suggesting the presence of the SIEA in the second-stage breast reconstructions, when a value of BMI ≥ 24 kg/m² is met, the SIEA and the IMA can theoretically achieve an end-to-end anastomosis at the 3rd to the 5th intercostal level, and when 24 kg/m²≤ BMI ≤ 25 kg/m², due to the large difference in diameters, the SIEA and the IMA at the 2nd intercostal level might need to adopt an end-to-side anastomosis or switch to the TDA recipient site. Based on this study's findings and aesthetic effect considerations, we think that the 3rd and the 4th intercostal planes are ideal choices for the end-to-end anastomosis. As a salvage recipient option, the TDA can theoretically achieve an end-to-end anastomosis with the SIEA at a value of BMI ≥ 24 g/m².

LEVEL OF EVIDENCE IV

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Bipedicled SIEA Flap with Deep Inferior Epigastric Artery and Vein Grafts for Breast Reconstruction

A superficial inferior epigastric artery (SIEA) flap can be an alternative to a deep inferior epigastric artery perforator (DIEAP) flap in cases where SIEAs are relatively well developed. Although an SIEA flap is less invasive than a DIEAP flap, the pedicles of the former are anatomically shorter, making it more difficult to choose recipient vessels when bilateral SIEAs are necessary. A 45-year-old female diagnosed with cancer of the left breast underwent mastectomy (specimen weight: 750 g) and immediate two-stage breast reconstruction using a free abdominal flap with bilateral pedicles was planned. Preoperative computed tomographic angiography showed that the bilateral DIEAPs in the flap were less than one millimeter in diameter, whereas the bilateral SIEAs were well developed enough for us to opt for a double-pedicled stacked SIEA flap. After the double-pedicled SIEA flap was elevated, folded, and temporarily placed in the subcutaneous pocket, the pedicle length on one side was found to be insufficient. Therefore, portions of the right composite deep inferior epigastric artery (DIEA) and vein (DIEV) grafts (roughly 7 cm) were collected from a short fasciotomy and anastomosed to the peripheral ends of the right SIEA and SIEV, respectively. Following this, the left SIEA and SIEV were antegradely anastomosed to the internal mammary artery and vein (IMA/IMV), while the DIEA/DIEV grafts were retrogradely anastomosed to the IMA/IMV, respectively. We recommend the proactive use of this method, as pedicle extension using the DIEA/DIEV grafts enables a higher degree of freedom in unilateral breast reconstruction using bilateral SIEA flaps.

Usefulness of Interposition Arteriovenous Bundle Graft in Free Flap Surgery: A Case Series and Systematic Review

BACKGROUND

The paucity of reliable recipient vessels adjacent to defects poses a great challenge in free flap reconstruction. Although the use of interposition vein grafts to cover the vascular gap is common, its potential association with higher risks of flap compromise is often reported. Interposition arteriovenous bundle grafts have been introduced as an alternative. This study aimed to evaluate the outcomes of free tissue transfer using interposition arteriovenous bundle grafts and to conduct a systematic review of studies that reported the use of the technique.

METHODS

Patients who underwent free tissue transfer using the interposition arteriovenous bundle graft technique were assessed for flap perfusion-related complications. A systematic review of literature was performed using pooled analysis to calculate the rate of perfusion-related complications.

RESULTS

Overall, 14 cases of free flap reconstruction used the interposition arteriovenous bundle graft technique to cover vascular gaps in diverse regions. The most common donor vessel of this graft was the descending branch of the lateral circumflex femoral vessels (mean length, 6.9 cm). All flaps survived except for 1 case of partial flap loss, showing a flap compromise rate of 7.1%. A systematic review identified 13 studies that represented 78 cases using this technique. In the pooled analysis, including the current series, the overall flap survival rate was 95.7%, reporting 4 of 92 cases of flap compromise.

CONCLUSIONS

The interposition arteriovenous bundle graft technique may help overcome the challenges of pedicle shortage or lack of adjacent recipient vessels in free flap reconstruction.

Vein Grafts in Free Flap Reconstruction: Review of Indications and Institutional Pearls

SUMMARY

Vein grafts enable soft-tissue reconstruction in cases of insufficient pedicle length, a lack of nearby recipient vessels, and a wide zone of injury caused by trauma or radiation therapy. The purpose of this article is to provide a comprehensive review of vein grafts in free flap reconstruction focusing on the timing of arteriovenous loops, complications, and surgical technique. Vein graft indications, types of vein grafts, and location-specific considerations are also reviewed. Three reconstructive microsurgeons at high-volume centers were asked to offer institutional pearls on the order of anastomosis, selection of donor veins, and timing of arteriovenous loops. In terms of gap length, vessel gaps less than 10 cm may be reconstructed with an interposition or transposition vein graft. For longer gaps, surgeons should consider the use of arteriovenous loops, transposition arteriovenous loops, or flow-through flaps. Both one and two-stage arteriovenous loops are used, depending on patient comorbidities, potential exposure of critical structures, and surgeon preference. Although one-stage arteriovenous loops expedite the reconstructive process, two-stage arteriovenous loops require shorter operations and help identify patients at risk of flap failure. Although whether the use of vein grafts increases flap failure rates is controversial, complications are highest in lower extremity reconstruction, cases of a prolonged interval between stages in two-stage arteriovenous loops, and unplanned vein grafts.

Harvesting Composite Arterial and Vein Grafts from Deep Inferior Epigastric Artery and Vein: A Safe Five-Step Method of Preparation

BACKGROUND

As the use of stacked flaps and options for autologous breast reconstruction increase, the level of complexity in autologous breast reconstruction has risen. Frequently, these reconstruction types present technical challenges such as vessel mismatches and short pedicle length. In this study, the authors introduce their five steps of harvesting composite deep inferior epigastric artery (DIEA) and deep inferior epigastric vein (DIEV) grafts to overcome such challenges.

METHODS

The authors performed a retrospective review of patients who underwent microvascular reconstruction using DIEA/DIEV grafts from 2012 to 2020. The grafts were harvested using the five steps, as follows: step 1, a transverse, paramedian skin incision was made at the level of suprapubic crease; step 2, an oblique fasciotomy was made on the lateral rectus border; step 3, DIEA/DIEV vessels were identified and exposed past the confluence of two venae comitantes; step 4, DIEA/DIEV grafts were harvested while sparing motor nerves; and step 5, fascial closure was performed.

RESULTS

A total of 40 DIEA/DIEV grafts were used in 25 patients (lumbar artery perforator flaps, n = 25; lateral thigh flaps, n = 1; superficial inferior epigastric artery flaps, n = 12; and flap salvage, n = 2) for breast reconstruction. The average time of harvest was 28 minutes, and there were two flap losses.

CONCLUSIONS

In the authors' experience, DIEA/DIEV grafts can be safely harvested and used in flaps with short pedicles and small vessel size. Although the authors' experience was limited to breast reconstruction, the DIEA/DIEV grafts can be used for other types of reconstruction, especially for head and neck reconstruction.

Matching the perforating branch of the internal thoracic artery and the deep inferior epigastric artery for breast reconstruction using multi-detector row computed tomography

PURPOSE

Matching the diameter of the deep inferior epigastric artery (DIEA) and perforating branch (PB) of the internal thoracic artery (ITA) is important for arterial anastomosis during breast reconstruction using the DIEA flap. An anatomic investigation of these arteries was performed using multidetector row computed tomography (MDCT).

PATIENTS AND METHODS

Contrast-enhanced MDCT data of 50 women (aged 18-90 years) covering the neck to the groin were analyzed. The diameter of the PBs of the ITA at their origins from the first to the sixth intercostal space and of the DIEA 20 mm from the bifurcation of the external iliac artery were measured.

RESULTS

The mean diameters of the right and left DIEAs were 1.53 ± 0.263 mm and 1.53 ± 0.306 mm, respectively. The diameter of the PBs in the second and third intercoastal spaces was the same as the diameter of the DIEA, bilaterally.

CONCLUSION

It is suggested that anastomosis of the DIEA with PBs of the ITA in the second and third intercoastal spaces is optimal for DIEA flap grafting. Our results could contribute to making vascular anastomosis easier, thereby reducing the burden on both surgeons and patients.

Simultaneous Circumferential Body Lift and Four-Flap Breast Reconstruction Using Deep Inferior Epigastric Perforator and Lumbar Artery Perforator Flaps

SUMMARY

The ideal autologous breast reconstruction provides a long-lasting and aesthetically pleasing result. The deep inferior epigastric perforator (DIEP) flap remains the gold standard for breast reconstruction; however, in a subset of patients, this flap may not provide adequate soft tissue to achieve the patient's aesthetic goals. The lumbar artery perforator flap has emerged as a useful adjunct to the DIEP flap for four-flap breast reconstruction, and also provides the patient with circumferential body contouring. From April 1 to July 1, 2019, the authors performed two bilateral stacked DIEP and lumbar artery perforator flap breast reconstructions. The authors retrospectively reviewed patient charts for pertinent data. Patients were chosen for reconstruction based on their physical examination and computed tomographic angiography findings. The operative technique used was unchanged for both reconstructions. The average total length of surgery was 553 minutes. The average DIEP flap weight was 510 g and the average lumbar artery perforator flap weight was 680 g. The average ischemia time for each lumbar artery perforator flap was 62 minutes. Length of stay was 3 days for both patients. This article describes the authors' approach to total breast reconstruction with stacked lumbar artery perforator flaps and DIEP flaps while also effectively performing a circumferential lower body lift. Critical components for success include appropriate patient selection and using a team approach with appropriately experienced staff at all levels of care.