Conjoined unification venoplasty for graft double portal vein branches as a modification of autologous Y-graft interposition

Single-Center Experience in Managing Right Liver Grafts From Trifurcation or Independent Right Posterior Portal Vein in Adult Living Donor Liver Transplantation

BACKGROUND

The right liver graft has sometimes been from the trifurcation portal vein (TPV) or independent right posterior portal vein (IRPPV). Managing these PV anatomies to increase the recipient's survival rate remains challenging. Many published techniques could overcome this problem, such as simple unification venoplasty (SUV), autologous portal Y-graft interposition, conjoined unification venoplasty (CUV) with a baseball-like conduit, and SUV plus circumferential fence-like vein extension. This study reviewed our strategy for managing the right liver grafts from TPV or IRPPV in adult living donor liver transplantation (aLDLT).

METHODS

We enrolled the study population who underwent aLDLT using the grafts with TPV or IRPPV at our institute from October 2004 to October 2022. We analyzed the reconstruction methods for these grafts and postoperative PV complications in donors and recipients.

RESULTS

During the study period, of 528 aLDLT recipients, we identified 26 donors with TPV (n = 10) or IRPPV (n = 16). Eight grafts from TPV had a single PV orifice. The other 18 grafts had dual right PVs that underwent initial PV management, including SUV (n = 13), recipient's right and left portal veins to graft's dual PVs (n = 2), Y-graft interposition (n = 1), CUV (n = 1) and SUV with fence-like vein extension (n = 1). One SUV graft changed to fence venoplasty due to significant tension for PV anastomosis. The acute right posterior PV thrombus and anterior PV stenosis happened in 2 cases with Y-graft interposition and native PVs direct anastomosis. One donor with TPV had portal vein thrombosis and needed thrombectomy with vein patch repair.

CONCLUSIONS

The graft from TPV should be carefully planned. A single PV orifice may be feasible but not always possible. An SUV could cover most IRPPVs, but if the distance between the right anterior and posterior PVs is a problem, CUV would be an alternative method. In addition, SUVs with fence venoplasty could relieve PV anastomosis tension.

Long-term results of conjoined unification venoplasty for multiple portal vein branches of the right liver graft in living donor liver transplantations

Background

Autologous portal vein Y-graft (PYG) interposition has been the standard procedure for reconstruction of double portal vein (PV) orifices of right liver grafts during living donor liver transplantations. However, it has the disadvantage of being vulnerable to anastomotic stenosis. A refined technique of conjoined unification venoplasty (CUV) was developed to secure PV reconstruction.

Methods

We reviewed the surgical outcomes in PV reconstructions using CUVs in 21 cases which were followed up for >3 years.

Results

The mean age of recipients was 51.7±4.9 years. The model for end-stage liver disease score was 15.3±6.4. The graft-recipient weight ratio was 1.12±0.21. Recipient PYGs were harvested in all cases. All living donors were blood relatives or relatives through marriage with type III PV anomalies. The number of right liver graft PV orifices was two in 19 cases and three in two cases. For the central intervening vein patch, a PV segment was used in six cases, and an autologous greater saphenous vein patch was used in the remaining 15 cases. The 21 patient cohort displayed a 100% 4-year patient survival rate. None of them underwent any PV interventions including interventional stenting. Serial follow-up computed tomography scans revealed that the reconstructed PV showed early reshaping with a stable streamlined configuration for over 3 years.

Conclusions

PV reconstruction using the CUV technique appears to be significantly more effective in preventing PV complications. We believe that CUV is a useful technique to reconstruct right liver grafts with multiple PV orifices.

Wedged-patch venoplasty of the left liver graft portal vein for size matching in pediatric living donor liver transplantation

Portal vein (PV) size matching between recipient and liver graft is important in preventing anastomotic stenosis in living donor liver transplantation (LDLT). In right liver grafts, the diameter of graft PV is usually >10 mm. Thus, PV size matching does not become critical in adult recipients. If the recipient PV is very large, funneling fence can be attached to graft PV. However, if the diameter of graft PV is <8 mm, it can induce anastomotic stenosis. We experienced a few cases of PV anastomotic stenosis due to small-sized graft PV in >5000 LDLT cases, but graft PV widening was not performed because graft PV is considered as being a no-touch area. In thinking out of the box, we performed wedged-patch venoplasty to exceptionally narrow graft PV. A 4 year-old female patient underwent second LDLT due to progressive deterioration of graft function after 3 years. At first LDLT operation for biliary stresia, an iliac vein conduit was interposed for PV reconstruction. At second LDLT operation, the diameter of interposed PV was 10 mm, but the left liver graft PV was only 6 mm-sized. Uniquely, the left PV was waist only at first-order PV. To resolve this PV waist, a longitudinal incision was made to release the waist. A cold-preserved fresh iliac vein patch was inserted to widen the PV orifice. The patch size was adjusted to match the size of the recipient PV. The patient recovered uneventfully. This wedged-patch venoplasty technique can be applied to small-sized graft PV, to cope with PV size mismatching in LDLT.

Conjoined unification venoplasty for triple portal vein branches of right liver graft: a case report and technical refinement

Anomalous portal vein (PV) branching of the donor liver is uncommon and usually makes two, or rarely, more separate PV branches at the right liver graft. Autologous PV Y-graft interposition has long been regarded as the standard procedure, but is currently replaced with the newly developed technique of conjoined unification venoplasty (CUV) due to its superior results. Herein, we presented a case of CUV application to three PV openings of a right liver graft. The recipient was a 32-year-old male patient with hepatitis B virus-associated liver cirrhosis. The living liver donor was his 33-year-old sister who had a type III PV anomaly, but the right posterior PV branch was bifurcated early into separate branches of the segments VI and VII, thus three right liver PV branches were cut separately. We used the CUV technique consisting of placement of a small vein unification patch between three PV orifices, followed by overlying coverage with a crotch-opened autologous portal Y-graft. The portal Y-graft was excised and its crotches were incised to make a wide common orifice. Three bidirectional running sutures were required to attach the crotch-opened autologous portal Y-graft. After portal reperfusion, the conjoined PV portion bulged like a tennis ball, providing a wide range of alignment tolerance. The patient recovered uneventfully from the liver transplantation operation. The CUV technique enabled uneventful reconstruction of triple donor PV orifices. Thus, CUV can be a useful and effective technical option for reconstruction of right liver grafts with various anomalous PVs.

Conjoined Unification Venoplasty for Double Portal Vein Branches of Right Liver Graft: 1-Year Experience at a High-Volume Living Donor Liver Transplantation Center

Autologous portal Y-graft (PYG) interposition has been regarded as the standard procedure for reconstruction of double portal vein (PV) orifices of right liver grafts during living donor liver transplantation, but it has the drawback of being vulnerable to functional PV stenosis. A refined technique of conjoined unification venoplasty (CUV) was developed to secure PV reconstruction. We reviewed the surgical experience on reconstruction of graft double PVs in 28 cases during a 1-year period of 2014. Computational simulation and modeling studies led us to develop CUV, which consists of placing a unification patch between two graft PV orifices and overlying the coverage with a crotch-opened autologous PYG, the shape of which provides a wide range of tolerance for alignment mismatching in PV anastomosis. During the 1-year study period, the numbers of patients using autologous PYG interposition, circumferential PV fencing with greater saphenous vein, homograft vein interposition, and CUV were 11, 3, 1, and 0, respectively, for 6 months before implementing CUV, and 5, 1, 1, and 6, respectively, for 6 months after implementing CUV. PV complications occurred in 2 of 16 patients with autologous PYG interposition, but no complications were observed in 12 patients operated on using other techniques including CUV. The drawback of conventional autologous PYG interposition can be overcome technically by CUV, which secures PV patency through hemodynamic-compliant offset of anatomical discrepancy and anastomotic alignment mismatching. We believe that CUV could be a useful and effective technical option for reconstruction of right liver grafts with two graft PVs.