Comparison of flow rates in the antegrade and retrograde internal mammary vein for free flap breast reconstruction

Utilizing the Retrograde Flow of Internal Mammary Vessels as a Donor Pedicle

Introduction  The aim of this study is to assess the results of retrograde flow of internal mammary artery and vein (IMA/V) as a donor vessel for free flap microvascular anastomosis (MVA). This need arises with bipedicle deep inferior epigastric perforator (DIEP) flaps, when all four zones with extra fat need to be harvested for unilateral breast reconstruction coupled with poor midline crossover of circulation naturally or because of midline scar. Large anterolateral thigh flaps for chest wall cover, with multiple perforators from separate pedicles, also need supercharging. This needs an additional source of donor vessels, antegrade IMA/V being the first one.

Materials and Methods  Retrospective study of microvascular breast reconstruction using retrograde internal mammary donor vessels.

Results  Out of 35 cases, 20 cases had distal IMA/V, with retrograde flow, as donor vessel for second set of arterial and venous anastomosis. In two cases, retrograde IMA/V was used for the solitary set of MVA. In remaining 13 cases, either retrograde IMA or V was utilized either as a principal or accessory donor. No flap was lost. Venous and arterial insufficiency happened in one case each, both were salvaged. Two cases developed partial necrosis, needing debridement and suturing. One case developed marginal necrosis. Only one case developed fat necrosis with superadded infection on follow-up.

Conclusion  Distal end of IMA and IMV on retrograde flow is safe for MVA as an additional or sole pedicle. It is convenient to use being in the same field. It enables preservation of other including thoracodorsal pedicle and latissimus dorsi flap for use in case of a complication or recurrence.

Internal Mammary Vein Valves: A Histological Study

It is widely accepted that the internal mammary vein (IMV) is valveless. However, few anatomical studies are available on the presence or absence of IMV valves. To test the hypothesis that the IMV is valveless, we performed microscopic histological examination of the IMV. IMV samples were collected from 10 human fresh frozen cadavers. For a control, the small saphenous vein (SSV) was obtained. Histological stains were performed. Microscopic examination showed that a venous valve was found in 8 of 20 IMVs. The structure of the valve leaflet consisted of two parts. There was a “thick part” located near the wall of the vein that consisted of smooth muscle cells and fibers. There was also a “thin part” located near the center of the venous lumen that lacked smooth muscle cells. The size of the thick part of the IMV valve was smaller than the SSV valve, whereas there was no difference in the size of the thin part between the IMV and SSV. IMV valves exist. Our results that an IMV valve was present in less than half of IMVs and there was a small-sized valve leaflet suggest that the IMV valve may be rudimentary.

Interdisciplinary Treatment of Breast Cancer After Mastectomy With Autologous Breast Reconstruction Using Abdominal Free Flaps in a University Teaching Hospital-A Standardized and Safe Procedure

Background: Breast cancer is the most common malignancy in women. The interdisciplinary treatment is based on the histological tumor type, the TNM classification, and the patient's wishes. Following tumor resection and (neo-) adjuvant therapy strategies, breast reconstruction represents the final step in the individual interdisciplinary treatment plan. Although manifold flaps have been described, abdominal free flaps, such as the deep inferior epigastric artery perforator (DIEP) or the muscle-sparing transverse rectus abdominis myocutaneous (ms-TRAM) flap, are the current gold standard for autologous breast reconstruction. This retrospective study focuses on the safety of autologous breast reconstruction upon mastectomy using abdominal free flaps. Methods: From April 2012 until December 2018, 193 women received 217 abdominal free flaps for autologous breast reconstruction at the University Hospital of Erlangen. For perforator mapping, we performed computed tomography angiography (CTA). Venous anastomosis was standardized using a ring pin coupler system, and flap perfusion was assessed with fluorescence angiography. A retrospective analysis was performed based on medical records, the surgery report, and follow-up of outpatient course. Results: In most cases, autologous breast reconstruction was performed as a secondary reconstructive procedure after mastectomy and radiotherapy. In total, 132 ms1-TRAM, 23 ms2-TRAM, and 62 DIEP flaps were performed with 21 major complications (10%) during hospital stay including five free flap losses (2.3%). In all cases of free flap loss, we found an arterial thrombosis as the main cause. In 24 patients a bilateral breast reconstruction was performed without free flap loss. The majority of free flaps (96.7%) did not need additional supercharging or turbocharging to improve venous outflow. Median venous coupler size was 2.5 mm (range, 1.5-3.5 mm). Conclusion: Using CTA, intraoperative fluorescence angiography, titanized hernia meshes for rectus sheath reconstruction, and venous coupler systems, autologous breast reconstruction with DIEP or ms-TRAM free flaps is a safe and standardized procedure in high-volume microsurgery centers.

Successful free flap salvage upon venous congestion in bilateral breast reconstruction using a venous cross-over bypass: A case report

Abdominal free flaps such as the muscle sparing transverse rectus abdominis myocutaneous (ms-TRAM) or deep inferior epigastric artery perforator (DIEP) flap represent the gold standard in autologous breast reconstruction. We describe a salvage procedure during bilateral free flap breast reconstruction due to insufficient venous drainage using a venous cross-over bypass. A 54-year-old woman with a thrombosis of the left subclavian port-system in the medical history was elected for simultaneous bilateral breast reconstruction with ms-TRAM and DIEP flaps. Intraoperatively, a venous congestion of the DIEP flap, which was connected to the left cranial internal mammary vessels, appeared. In the absence of sufficient ipsilateral venous recipient vessels, we performed a salvage procedure requiring a 15 cm small saphenous vein graft and presternal subcutaneous tunneling. The flap vein was anastomosed end-to-end with the contralateral caudal internal mammary vein using a coupler system. The postoperative course was uneventful and both flaps survived. We describe the cross-over venous emergency bypass as a useful tool in unexpected venous thrombosis during bilateral free flap breast reconstruction.

Nipple-sparing mastectomy and breast reconstruction with a deep inferior epigastric perforator flap using thoracodorsal recipient vessels and a low lateral incision

BACKGROUND

Nipple-sparing mastectomy poses challenges in providing esthetically-pleasing immediate autologous breast reconstruction. This study was to investigate the outcomes of nipple-sparing mastectomy with breast reconstruction using free abdominal flaps between two different recipient sites.

METHODS

Between 2010 and 2016, 79 patients who underwent nipple-sparing mastectomy with autologous breast reconstruction using thoracodorsal (TD) vessels in 30 cases or internal mammary (IM) vessels in 49 cases were investigated. Demographics, intraoperative findings, complications, and quality of life using Breast-Q questionnaire were compared between two groups.

RESULTS

All flap survived. There was no statistical difference in age, BMI, ischemia time, and flap-used percentage. The TD artery had a statistically smaller diameter 1.8 ± 0.4 mm than the IM artery 2.7 ± 0.43 mm (p = 0.02). At a mean follow-up of 44.4 ± 35.2 months, there was no statistical difference in total complication rates between TD and IM groups (23.3% and 36.7%, respectively, p > 0.05). The "psychosocial well-being" of Breast-Q in TD group 83.9 ± 14.6 was statistically greater than IM group 72.8 ± 17.6 (p = 0.04).

CONCLUSIONS

Nipple-sparing mastectomy with immediate breast reconstruction using TD vessels with a low lateral scar is a safe procedure that provides an inconspicuous scar with better cosmesis and minimal complication rate.

Automatic Early-Onset Free Flap Failure Detection for Implantable Biomedical Devices

OBJECTIVE

Up to 10% of free flap cases are compromised, and without prompt intervention, amputation and even death can occur. Hourly monitoring improves salvage rates, but the gold standard for monitoring requires experienced personnel to operate and suffers from high false-positive rates as high as 31% that result in costly and unnecessary surgeries. In this paper, we investigate free flap patency monitoring using automatic hardware-only classification systems that eliminate the need for experienced personnel. The expected flow ranges of the antegrade and retrograde veins for breast reconstruction are studied using a syringe pump to create the laminar flow seen in veins.

METHODS

Feature data extracted from the Doppler blood flow signals are analyzed for sensitivity, specificity, and false-positive rates. Hardware is built to perform the classification automatically in real-time and output a decision at the end of the observation period.

RESULTS

Experimental results using the hardware-only classifier for a 50 ms window size show high sensitivity (96.75%), specificity (90.20%), and low false-positive rate (9.803%). The experimental and theoretical classification results show close agreement.

CONCLUSION

This work indicates that automatic hardware-only classifiers can eliminate the need for experienced personnel to monitor free flap patency.

SIGNIFICANCE

The hardware-only classification is amenable to a monolithic implementation and future studies should study a totally implantable wirelessly-powered blood flow classifier. The high classifier performance in a short window period indicates that duty-cycled powering can be used to extend the safe operational depth of an implant. This is particularly relevant for the difficult buried free flap applications.

Anastomosis of the Superficial Inferior Epigastric Vein to the Internal Mammary Vein to Augment Deep Inferior Artery Perforator Flaps

Use of the retrograde limb of the internal mammary vein has been described previously as a lifeboat for venous congestion but not prophylactically. Maximizing the length of the deep inferior artery perforator (DIEP) flap pedicle, identifying and dissecting the superficial inferior epigastric vein proximally in every patient, and taking advantage of the retrograde internal mammary vein are all technical details that facilitate the additional venous anastomosis and flap inset. Performing a second venous anastomosis routinely using the superficial inferior epigastric vein to the retrograde internal mammary vein helps with flap inset.

Salvage of a TRAM breast reconstruction flap using the retrograde internal mammary artery system

Background:

Free tissue transfer provides an optimal means for breast reconstruction in creating an aesthetically natural appearance that is durable over time. The choice of donor vessels vary from surgeon to surgeon, but the internal mammary axis is one of the most popular choices together with the thoracodorsal vessels.

Aims and Results:

We present the case of a salvaged free transverse rectus abdominis myocutaneous breast reconstruction in which end-to-end antegrade anastomosis to the internal mammary artery (IMA) was not possible due to frail vessel walls, but retrograde anastomosis to the IMA and antegrade anastomosis of internal mammary vessel resulted in a perfused and viable flap.

Conclusion:

We suggest the use of the retrograde internal mammary arterial system for microsurgical anastomosis when the anterograde flow is not adequate, the vessel wall is friable, and when other more common options are not available.

Cephalic Vein Transposition versus Vein Grafts for Venous Outflow in Free-flap Breast Reconstruction

Introduction:

When recipient veins for free-flap breast reconstruction are unavailable or inadequate, vein grafts or cephalic vein transposition (CVT) an option to provide alternate venous outflow. There are no comparative data to elucidate the indications and outcomes for each. We hypothesize that the CVT is as reliable as vein grafts when indicated.

Methods:

All consecutive cases where a CVT or venous vein grafts were used for free-flap breast reconstruction between 2000 and 2012 were reviewed. Patient demographics, operative notes, indications, and flap survival were compared between the 2 groups.

Results:

Ten patients underwent a CVT and 38 patients received a vein graft for insufficient venous outflow. There were no differences in average age, body mass index, or comorbid conditions between the groups. Similarly, there was no difference in previous radiotherapy, timing of reconstruction, or side of reconstruction. A CVT was used for salvage following venous thrombosis in 7 patients (70.0%) and for primary venous outflow in the remaining patients due to inability to use the internal mammary vein. Vein grafts were performed primarily in 31 patients, 22 for augmenting venous drainage (supercharge), 9 for the dominant venous outflow, and 7 for salvage of a thrombosis. One patient in each group suffered a complete loss of the free flap (cephalic: 10.0% vs vein graft: 14.3%, P = 0.36).

Conclusions:

The CVT is a reliable alternate venous outflow that can be used as a primary recipient vein or as a salvage option following venous thrombosis. Surgeons should consider a CVT when primary recipient veins are compromised or unavailable.