Effective anatomic reconstruction of the middle hepatic vein in modified right lobe graft living donor liver transplantation

Technical Refinement to Prevent Hepatic Outflow Disturbance in Right Lobe Living Donor Liver Transplantation: The New Simplified One-Orifice Venoplasty Technique

Middle hepatic vein (MHV) reconstruction is often essential to avoid hepatic congestion and serious graft dysfunction in living donor liver transplantation (LDLT). This article introduces the evolution of our MHV reconstruction technique and the excellent outcomes of a new simplified one-orifice venoplasty. We compared clinical outcomes among 3 types of one-orifice techniques through a retrospective review of 378 recipients who underwent LDLT using a modified right lobe graft at our institution from January 2008 to December 2018; group I (n = 34) received separate outflow reconstruction, group II (n = 166) received the one-orifice technique to create a wider single outflow with patchwork, and group III (n = 178) received the more simplified one-orifice technique in which neo-MHV was reconstructed into the right hepatic vein without patch venoplasty. Patient demographic characteristics did not differ significantly among the 3 groups, but cold ischemic time and operative time in groups II and III were significantly shorter than those in group I. Moreover, the early patency rates of MHV in groups II and III were higher than those in group I. In particular, group I received an MHV or right hepatic vein stenting more frequently than group II or III during the early posttransplant period. In conclusion, this new simplified one-orifice technique could be an effective method to overcome technical difficulties and the outflow disturbance during right lobe LDLT without complex benchwork to create a large outflow.

Middle hepatic vein reconstruction in adult living donor liver transplantation: a randomized clinical trial

BACKGROUND

In adult right lobe living donor liver transplantation (LDLT), venous drainage of the anterior sector is usually reconstructed on the bench to form a neo-middle hepatic vein (MHV). Reconstruction of the MHV for drainage of the anterior sector is crucial for optimal graft function. The conduits used for reconstruction include cryopreserved allografts, synthetic grafts, or the recipient portal vein. However, the ideal choice remains a matter of debate. This study compares the efficacy of the native recipient portal vein (RPV) with PTFE grafts for reconstruction of the neo-MHV.

METHODS

Patients in this equivalence-controlled, parallel-group trial were randomized to either RPV (62 patients) or PTFE (60 patients) for use in the reconstruction of the neo-MHV. Primary endpoint was neo-MHV patency at 14 days and 90 days. Secondary outcomes included 90-day mortality and post-transplant parameters as scored by predefined scoring systems.

RESULTS

There was no statistically significant difference in the incidence of neo-MHV thrombosis at 14 days (RPV 6.5 per cent versus PTFE 10 per cent; P = 0.701) and 90 days (RPV 14.5 per cent versus PTFE 18.3 per cent; P = 0.745) between the two groups. Irrespective of the type of graft used for reconstruction, 90-day all-cause and sepsis-specific mortality was significantly higher among patients who developed neo-MHV thrombosis. Neo-MHV thrombosis and sepsis were identified as risk factors for mortality on Cox proportional hazards analysis. No harms or unintended side effects were observed in either group.

CONCLUSION

In adult LDLT using modified right lobe graft, use of either PTFE or RPV for neo-MHV reconstruction resulted in similar early patency rates. Irrespective of the type of conduit used for reconstruction, neo-MHV thrombosis is a significant risk factor for mortality.

REGISTRATION NUMBER

CTRI/2018/11/016315 (www.ctri.nic.in).

Strategy for Selective Middle Hepatic Vein Reconstruction in Living Donor Liver Transplantation Using Right Lobe Graft: A Retrospective Observational Study

BACKGROUND

The aim of this study was to verify the safety and feasibility of our selection criteria for middle hepatic vein (MHV) reconstruction in living donor liver transplantation (LDLT) using right lobe grafts.

METHODS

A total of 153 LDLTs were performed using right lobe grafts in a tertiary hospital from 2006 to 2016. Among them, 52 cases without MHV reconstruction were compared with 101 recipients who underwent LDLT using right lobe graft with MHV reconstruction. Both groups were compared regarding indications for reconstruction, short-term and long-term complications, operative details, and outcomes.

RESULTS

The two groups differed only in cold ischemic time (108.19 ± 49.81 minutes vs 146.37 ± 58.74 minutes) preoperatively. Short-term posttransplant outcomes, long-term overall survival, and long-term disease-free survival showed no significant differences between the 2 groups. After propensity score matching for both groups with and without MHV reconstruction to eliminate selection bias, the 2 groups were comparable.

CONCLUSIONS

We found that our selection criteria for performing MHV reconstruction in LDLT using right lobe graft were feasible and safe. A routine MHV reconstruction is not necessary if the right lobe graft graft-to-recipient weight ratio is ≥1.0, right hepatic vein draining territory volume is ≥0.8, and recipient Model for End-Stage Liver Disease score is <20.

Single Orifice Outflow Reconstruction: Refining the Venous Outflow in Modified Right Lobe Live Donor Liver Transplantation

BACKGROUND

MHV reconstruction is essential to avoid anterior sector congestion in adult live donor liver transplantation (LDLT) using a modified right lobe graft.

AIMS

The objective of this study is to evaluate the graft and patient outcomes with single orifice outflow reconstruction technique (SORT) (RHV + neo-MHV combined reconstruction on IVC) vs. dual outflow reconstruction technique (DORT) (RHV and neo-MHV separately reconstructed on IVC) in a modified right lobe LDLT.

METHODS

Prospectively collected data of consecutive patients undergoing LDLT from June 2011 to August 2018 were analyzed. The patients were divided into two groups: SORT (n = 207) and DORT (n = 108). The perioperative morbidity and mortality were compared between two groups.

RESULTS

The two groups were comparable in baseline preoperative characteristics. Intraoperatively, warm ischemia time (27 vs. 45 min, p < 0.001), anhepatic phase (132 vs. 159 min, p < 0.001), and operative time (680 vs. 840 min, p < 0.001) were significantly shorter in SORT group. SORT group also had significantly lower GRWR (0.92 vs. 1.06, p < 0.001) and higher portal flow (2.4 vs. 2.7 L/min, p = 0.02). Postoperatively, SORT group had lower peak AST (177 vs. 209 IU/L, p < 0.001), ALT (163 vs. 189 IU/L, p = 0.004), creatinine levels (0.98 vs. 1.10, p = 0.01), rate of severe sepsis (13.7% vs. 22.9%, p = 0.03), major morbidity (50.7% vs. 62.6%, p = 0.03), shorter ICU (9 vs. 14 days, p < 0.001), and hospital stay (21 vs. 26 days, p = 0.03). Overall survival rates were comparable.

CONCLUSION

A SORT leads to improved early graft function and perioperative morbidity in modified right lobe LDLT in spite of having lower GRWR and higher portal flow.

Inferior Vena Cava and Venous Outflow Reconstruction in Living Donor Liver Transplantation in Children: A Single-Center Retrospective Study and Literature Review

Background

In this report, we present technical problems and solutions used in the reconstruction of the inferior vena cava and graft venous outflow during living donor liver transplantation (LDLT) in children.

Material/Methods

In 65 grafts out of 379 liver transplantations from living donors, reconstruction of multiple hepatic venous branches and/or IVC was necessary. In 4 cases, cryopreserved deceased donor venous grafts were used for the reconstruction of the IVC and/or HV.

Results

Follow-up ranged from 2 months to 17.8 years (median 7.2 years). In 4 children, liver re-transplantation was required for a reason not related to venous outflow (biliary complications in 3 patients, graft insufficiency caused by small-for-size syndrome). Two patients died: 1 due to tumor recurrence and 1 due to multi-organ failure. Fifty-nine patients are alive with good liver function. One patient (1.5%) after deceased donor venous graft reconstruction showed symptoms of venous outflow obstruction, which was successfully treated with endovascular balloon angioplasty and stent placement. The remaining 59 transplanted patients do not show any signs of venous outflow obstruction.

Conclusions

In most cases, the reconstruction of multiple hepatic veins of living donor allografts can successfully be done with local venoplasty, while using cold-stored vein grafts may be helpful in selected cases of LDLT.

Single Orifice Outflow Reconstruction in Various Tributaries of the Right Liver Graft Using Commercialized Polyethylene Terephthalate Y-graft: A technical Simplification of Venous Reconstruction in 3 Cases

BACKGROUND

Hepatic vein reconstruction is very important in living donor liver transplantation to prevent outflow obstruction and maintain the graft function. In right liver grafts, reconstruction of the tributary of the middle hepatic vein (MHV) or inferior hepatic vein (IHV) is mandatory, and several options are recommended. Recently, it has been reported that a single, wide orifice is an important perquisite for adequate outflow in liver transplantation. This can be achieved by various venoplasty techniques in back table procedures using the recipient's saphenous vein, a cryopreserved vascular graft, or a synthetic vascular graft.

METHODS

Due to the insufficiency of an actual graft, we used a simple back table technique with the polyethylene terephthalate Y-graft in 3 cases of right liver grafting between October 2015 and September 2019 in Gil Medical Center. We used both arms of the Y-graft for anastomosis of the 2 largest branches of both tributaries. The main trunk of the Y-graft was then joined to the right hepatic vein (RHV). We analyzed these patients' outcomes retrospectively and the study was approved by institutional review board in Gachon University Gil Medical Center. This study strictly complies with the Helsinki Congress and the Istanbul Declaration regarding donor source and informed consent was obtained from all patients.

RESULTS

All 3 patients had good tributary patency and allograft function at discharge. The patency of the graft was maintained over a period ranging from 2 months to 2 years, without any anticoagulant administration. Regardless of the tributary patency, all patients survived with good outflow of the grafts.

CONCLUSIONS

Although we had little prior experience in synthetic venous grafts, these cases indicate some interesting findings, with a simple and intuitive procedure. We believe our technique is a practical method for manipulating various venous tributaries in a right liver graft.

Vascular complications after adult living donor liver transplantation: Evaluation with ultrasonography

Living donor liver transplantation (LDLT) has been widely used to treat end-stage liver disease with improvement in surgical technology and the application of new immunosuppressants. Vascular complications after liver transplantation remain a major threat to the survival of recipients. LDLT recipients are more likely to develop vascular complications because of their complex vascular reconstruction and the slender vessels. Early diagnosis and treatment are critical for the survival of graft and recipients. As a non-invasive, cost-effective and non-radioactive method with bedside availability, conventional gray-scale and Doppler ultrasonography play important roles in identifying vascular complications in the early postoperative period and during the follow-up. Recently, with the detailed vascular tracing and perfusion visualization, contrast-enhanced ultrasound (CEUS) has significantly improved the diagnosis of postoperative vascular complications. This review focuses on the role of conventional gray-scale ultrasound, Doppler ultrasound and CEUS for early diagnosis of vascular complications after adult LDLT.

Adult right living-donor liver transplantation with special reference to reconstruction of the middle hepatic vein

Two hundred fifty-three consecutive living-donor liver transplant recipients with a right liver graft (RLG) were divided into three groups: an extended right liver graft (ERLG) group (n = 47) in which the middle hepatic vein (MHV) trunk was included in the graft, a modified right liver graft (MRLG) group (n = 114) in which the MHV tributaries were reconstructed with cryopreserved homologous veins and a simple RLG group (n = 92) in which the MHV tributaries were sacrificed. The volume of the anterior sector was significantly impaired in the RLG group compared to the other two groups, whereas the volume of the posterior sector was significantly improved in the RLG group, indicating that the impaired anterior sector regeneration by MHV deprivation was compensated by the posterior sector regeneration. The regeneration rate of the anterior sector was highest in the ERLG group (92%), moderate in the MRLG group (71%) and lowest in the RLG group (52%). The whole graft regeneration rate of the ERLG group was significantly higher than that of the other two groups. Poor regeneration, however, was not correlated with delayed functional recovery or long-term outcome. Short-term, the patency of reconstructed MHV tributaries was over 90%, but occlusion occurred frequently over the long-term, especially in V5.

Reconstructing middle hepatic vein tributaries in right-lobe living donor liver transplantation

AIMS

To investigate the effectiveness of our technique and policy in reconstructing middle hepatic vein (MHV) tributaries of patients undergoing right-lobe living donor liver transplantation (LDLT).

METHODS

From January 2001 to December 2010, 186 adult patients underwent right-lobe LDLT without the MHV. Patients were divided into two groups: group A (n = 71) and group B (n = 115) without or with the MHV tributaries reconstruction. We evaluated the serum liver function markers after transplantation and monitored vascular flow in the graft and interpositional vein by Doppler ultrasonography.

RESULTS

The cumulative 1-, 3-, 5-year graft and patient survival rates were not significant between group A and group B (p = 0.287 and p = 0.258). Biliary complications appeared to be more frequent in group A than in group B (16.9 vs. 5.2%, p = 0.009). Liver function impairment was found in patients without MHV reconstruction and those with occluded interpositional vessels early after transplantation. The cumulative 1-, 3-, 6- and 12-month patency rate of the interpositional veins was 81.51, 79.60, 74.69 and 72.68%, respectively.

CONCLUSION

The reconstruction technique based on our policy ensures excellent outflow drainage and favorable recipient outcome, while better criteria for MHV reconstruction should be established.

[Specific considerations in living-donor liver transplantation]

INTRODUCTION

Due to the limited number of cadaver donors, adult living liver donor transplantation became an alternative for liver transplantation. During living liver donor transplantation, the safety and uncomplicated recovery of the donor are as important as the appropriate volume and weight of the donated graft. The middle hepatic vein causes a significant dilemma, due to the special anatomical position. The reconstruction of the middle hepatic vein branches supplying S5, S8 is suggested when the anatomically right liver lobe is transplanted.

AIM

The aim of the present study was to investigate the requirements of the reconstruction of middle hepatic vein and to give an accurate description about the discrepancy between the portal vein in- and outflow.

METHOD

The authors analyzed the liver anatomic characteristics of 130 donors undergoing living liver donor transplantation with the use of MeVis software. The so-called porto-hepatic disparity index (shift) was introduced.

RESULTS

The right hepatic vein was dominant in 64.6% of all cases, while the left hepatic vein was never observed to be dominant. The territories of V5 and V8 were responsible for the 33.2±8.9% of the right hepatic lobe area. The correlation between portal venous territory and vein dominancy were as follows: R2 = 0.7811 in the left liver lobe; R² = 0.5463 in the area of middle hepatic vein and R² = 0.5843 in the case of the right hepatic vein. The average value of the shift was 28.2%.

CONCLUSIONS

The differences among the pattern of portal in- and hepatic outflow is an important issue that should be taken into consideration when deciding the necessity for reconstruction of the middle hepatic vein.

Obstruction at middle hepatic venous tributaries in modified right lobe grafts after living-donor liver Transplantation: diagnosis with contrast-enhanced US

PURPOSE

To investigate the ability of contrast material-enhanced ultrasonography (US) to help diagnose obstruction of middle hepatic venous (MHV) tributaries soon after living-donor liver transplantation with modified right lobe grafts.

MATERIALS AND METHODS

The institutional review board approved the study and waived requirement for informed consent. Sixty-five consecutive patients (48 men, 17 women; mean age, 52.8 years; range, 33-69 years) who underwent living-donor liver transplantation with modified right lobe grafts between February and May 2009 were included. All patients underwent contrast-enhanced US and Doppler US on postoperative day 1 and underwent computed tomography (CT) within 7 days after US. At contrast-enhanced US, parenchymal enhancement patterns in the territory of each MHV tributary during arterial and portal venous phases were evaluated. With use of most frequent enhancement patterns in patients with obstruction at MHV tributaries as a criterion, diagnostic performance of contrast-enhanced US was compared with that of Doppler US for diagnosis of obstruction at MHV tributaries; CT was the reference standard. Generalized estimating equations were used to adjust for data clustering.

RESULTS

Of 148 MHV tributaries in 65 patients, 36 (24.3%) in 31 patients were diagnosed as obstructed at CT. With arterial high echogenicity or portal low echogenicity used as a criterion for hepatic venous obstruction, contrast-enhanced US had sensitivity, specificity, and accuracy of 91% (33 of 36), 97% (109 of 112), and 95% (142 of 148), respectively, whereas Doppler US had values of 83% (30 of 36), 86% (97 of 112), and 85% (127 of 148), respectively. Contrast-enhanced US was significantly more specific and accurate than Doppler US for diagnosis of obstruction at MHV tributaries (P=.024 and .01, respectively). Arterial high echogenicity was noted only in the hepatic venous obstruction group.

CONCLUSION

Contrast-enhanced US can help accurately assess hepatic venous obstruction at MHV tributaries after living-donor liver transplantation with a modified right lobe graft. Contrast-enhanced US was significantly more specific than Doppler US, with arterial hyperenhancement in the affected area being specific to hepatic venous obstruction.

Clinical significance of right hepatectomy along the main portal fissure on donors in living donor liver transplantation

There might be discordance between inter-lobar borders of the main portal fissure (MPF) using the middle hepatic vein (MHV) and of the portal segmentation. Forty-five living donors who underwent right hepatectomy for the adult recipients from 2007 to 2011 in a tertiary hospital were retrospectively analyzed. The donors were classified into conventional right hepatectomy along the MPF (cRL group, n = 26) and modified right hepatectomy along right-side shifted transection plane from the MPF (mRL group, n = 19). The cRL donors had higher postoperative peak level of INR (1.84 vs. 1.62; P = 0.022), and bilirubin (3.37 mg/dl vs. 2.74 mg/dl; P = 0.065) than the mRL donors. cRL donors experienced greater depression of platelet count (144 per nL vs. 168 per nL; P = 0.042) and enlargement of splenic volume (52% vs. 37%; P = 0.025) than mRL donors for 7 days after hepatectomy. The regeneration of the left lateral sector was more accelerated in the cRL donors than the mRL donors for postoperative 3 months (148% vs. 84%; P = 0.015). There were no differences in the post-transplant graft function, incidence of complications, and graft survival rates between the two groups of recipients (P > 0.05). This study suggests that the conventional right hepatectomy along the MHV might increase donor risk by reducing parenchymal liver volume of the segment IV.

Volumetry-based selection of right posterior sector grafts for adult living donor liver transplantation

To determine the feasibility of volumetric criteria without anatomic exclusion for the selection of right posterior sector (RPS) grafts for adult-to-adult living donor liver transplantation (LDLT), we reviewed and compared our transplant data for RPS grafts and right lobe (RL) grafts. Between January 2008 and September 2010, adult-to-adult LDLT was performed 65 times at our institute; 13 of the procedures (20%) were performed with RPS grafts [the posterior sector (PS) group], and 39 (60%) were performed with RL grafts (the RL group). The volumetry of the 13 RPS donor livers showed that the RPS volume was 39.8% ± 7.6% of the total liver volume. Ten of the 13 donors had to donate RPS grafts because the left liver volume was inadequate. All donor procedures were performed successfully, and all donors recovered from hepatectomy. However, longer operative times were required for the procurement of RPS grafts versus RL grafts (418 ± 40 versus 345 ± 48 minutes, P < 0.001). The postoperative recovery of liver function was smoother for the donors of the PS group versus the donors of the RL group. The RPS grafts had significantly smaller hepatic artery and bile duct openings than the RL grafts. All recipients with RPS grafts survived LDLT. No recipients experienced vascular graft complications or small-for-size graft dysfunction. There were no significant differences in the incidence of posttransplant complications between the donors and recipients of the PS and RL groups. The 3-year graft survival rates were favorable in both groups (100% in the PS group versus 91% in the RL group). In conclusion, the selection of RPS grafts by volume criteria is a feasible strategy for an adult-to-adult LDLT program.

Emergent right lobe adult-to-adult living-donor liver transplantation for high model for end-stage liver disease score severe hepatitis

The aim of this study was to explore the feasibility of emergency right lobe adult-to-adult living-donor liver transplantation (LDLT) for high model for end-stage liver disease (MELD) score severe hepatitis. Consecutive 10 high MELD score severe hepatitis patients underwent emergency right lobe adult-to-adult LDLT in our hospital from April to December 2007. The MELD score was 34.50 +/- 2.088. The outcomes of these recipients were retrospectively analyzed. Among them, eight cases of ABO blood group were identical and two cases compatible, one case was Rh negative. Two recipients died and the rest of the recipients and all donors are safe; perioperative and 2-year survival rate was 80%. The mean graft-recipient weight ratio (GRWR) was 1.27% +/- 0.25%, and graft volume to recipient standard liver volume ratio (GV/ESLVR) was 56.7% +/- 6.75%. Of the 10 patients, three received right lobe grafts with middle hepatic vein (MHV), four without MHV, three without MHV but followed by V and VIII hepatic vein outflow reconstruction. An encouraging outcome was achieved in this group: elevated serum creatinine, serum endotoxin, decreased serum prothrombin activity, and Tbil returned to normal on postoperative days 3, 7, 14, and 28, respectively. One-year survival rate was 80%. Outcomes of emergency right lobe adult-to-adult LDLT for high MELD score severe hepatitis were fairly encouraging and acceptable. Emergency right lobe adult-to-adult LDLT is an effective and life-saving modality for high MELD score acute liver failure patients following severe hepatitis.

Duct-to-duct biliary reconstructions and complications in 100 living donor liver transplantations

OBJECTIVE

We evaluated the risk factors for biliary complications and surgical procedures for duct-to-duct reconstructions in adult living donor liver transplantation (LDLT).

PATIENTS AND METHODS

From February 2005 to March 2008, we performed 100 cases of adult LDLT with duct-to-duct biliary reconstruction, using 64 right lobe grafts, 33 left lobe grafts, and 3 right lateral grafts. We employed 4 types of duct-to-duct procedures: all interrupted 6-0 Prolene suture (group 1, n = 9); continuous posterior and interrupted anterior wall 6-0 Prolene suture (group 2, n = 49); all continuous 7-0 Prolene suture (group 3, n = 26); and all continuous 7-0 Prolene suture with external stent (group 4, n = 16). Biliary complications were defined as an anastomosis stricture or a leakage.

RESULTS

Thirty-four patients experienced biliary complications during the follow-up period (median, 27 months). The incidence of stricture was 27% and that of leakage, 8%. There were no perioperative, intraoperative, or anatomic risk factors for biliary complications, except the type of duct-to-duct procedure. Group 1 and 2 patients showed higher incidences of biliary strictures than groups 3 and 4 (43.1% vs 4.7%; P = .00). Group 3 patients experienced a higher incidence of bile leakage than the other groups (23.1% vs 2.7%; P = .004).

CONCLUSIONS

The type of biliary reconstruction is a factor affecting biliary complications following duct-to-duct anastomosis in LDLT. Duct-to-duct biliary anastomosis with 7-0 monofilament suture and a small external stent is a feasible procedure in LDLT that significantly reduces the incidence of biliary complications.

Sonographic evaluation of vessel grafts in living donor liver transplantation recipients of the right lobe

AIM

To evaluate the vessel grafts (VG) used to reconstruct the middle hepatic vein (MHV) tributaries with ultrasonography.

METHODS

Twenty-four patients undergone living donor liver transplantation were enrolled in our study. MHV tributaries larger than 5 mm in diameter were reconstructed with interposition VG. Blood flow of the graft and interposition VG was checked by Doppler ultrasonography daily in the first 2 postoperative weeks and monthly followed up after discharge. The sensitivity of VG detected by ultrasonography was assessed using surgical records as references. Student's t test was used to compare the velocity of VG and occluded VG in chronic patents (> 3 mo).

RESULTS

Thirty-one VG were used to reconstruct the MHV tributaries. Ultrasonography identified 96.7% (30/31) of large MHV tributaries and 90.3% (28/31) of VG. The diameter of VG was 5.6 +/- 0.8 mm and the velocity of VG was 19.7 +/- 8.1 cm/s. Two VG (2/31, 6.5%) were occluded on the first postoperative day in one patient who suffered from persistent ascites and had a prolonged recovery of liver function. Twenty-six VG (26/31, 83.9%) were patent 2 wk after operation. Six (6/31, 19.4%) VG were patent over 3 mo after operation. Intrahepatic venous collaterals were detected in 29.2% (7/24) patients. The velocity of VG and occluded VG was 30.1 +/- 5.6 cm/s, 16.5 +/- 5.8 cm/s, respectively, in chronic patents. The difference between two groups was statistically significant (P < 0.001).

CONCLUSION

Our results indicate that most VG are patent in the first postoperative week while only a small portion with a higher velocity remains patent after 3 mo. Intrahepatic venous collaterals can be observed in some patients after occlusion of VG.