Cryopreserved iliac artery is indispensable interposition graft material for middle hepatic vein reconstruction of right liver grafts

Imaging Evaluation of the Living Liver Donor: A Systems-Based Approach

Liver transplant is the definitive treatment of end-stage liver disease and early hepatocellular carcinoma. The number of liver transplant surgeries done is highly affected by the number and availability of deceased donor organs. Living donor liver transplantation has emerged as an alternative source of donors, increasing the availability of organs for transplant. Many factors must be considered when choosing living donor candidates to maintain a high level of donor safety and organ survival. To that end, potential donors undergo a rigorous pre-donation workup.

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.

Successful use of venous graft from native liver with hepatocellular carcinoma during living donor liver transplantation with no impact on recurrence rate: A retrospective cohort study

Introduction

There are still debates regarding using portal vein (PV) from liver with hepatocellular carcinoma (HCC) for vascular reconstruction. This study aimed to assess the feasibility and patency of PV venous graft from an explanted liver with HCC for the reconstruction of the hepatic veins tributaries or PV in living donor liver transplantation (LDLT) and to see if it has any risk on recurrence of HCC.

Patient and methods

We conducted a retrospective study on 81 patients with HCC who underwent LDLT from April 2004 to July 2022.

Results

Venous graft from native liver PV was used for vascular reconstruction in 31 patients as follows; reconstruction of V5 in 7 patients, V8 in 4 patients, V6 in 3 patients, combined V5 and V8 in 4 patients, V6 with V5/V8 in 5 patients, and as Y shape venous graft for 2 PV reconstruction in 8 patients. The implantation of the new conduit PV graft after reconstruction of the anterior sector tributaries was direct to the IVC in 8 patients, and to the common orifice of the left and middle hepatic veins in 12 patients. The 1 month, 3 months, and 1-year overall patency of the venous graft was 93.5%, 90.3%, and 84%, respectively. Nine patients had recurrent HCC. In multivariate analysis, the independent risk factors for HCC recurrence were AFP >400 ng/mL (HR = 1.47, 95% CI: 1.69–2.31, P = 0.01), moderate/poor differentiated tumor (HR = 3.06, 95% CI: 2.58–6.29, P = 0.02), and microvascular invasion (HR = 2.51, 95% CI: 1.05–1.93, P = 0.01). Using a PV venous graft had no risk factor for HCC recurrence (P = 0.9).

Conclusion

The use of PV venous graft of native liver with HCC for venous reconstruction is a feasible and valuable option in LDLT with good patency rates and no risk of HCC recurrence.

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The use of PV venous graft of native liver with HCC for venous reconstruction is a feasible and valuable option in LDLT.

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It has good patency rates and no risk on HCC recurrence.

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The independent risk factors for HCC recurrence in our study were AFP >400 ng/mL, moderate/poor differentiated tumor, and microvascular invasion.

Partial Inferior Vena Cava Reconstruction with Cryopreserved Aortic Homograft Following Resection for Malignancy

Malignant invasion of the inferior vena cava (IVC) often necessitates complete tumor thrombectomy and IVC reconstruction. Bovine pericardial xenografts and prosthetic grafts are frequently used for partial or entire IVC reconstruction with adequate subsequent patency and freedom from thrombosis. Cryopreserved aortic homografts represent an alternative conduit for vena cava replacement with resistance to infection in contaminated fields or following extensive retroperitoneal dissection. Specific reports of aortic homograft use for IVC reconstruction are scarce. Described are 2 cases of cryopreserved aortoiliac artery allograft use for long segment cava patch repair while avoiding extensive caval reconstruction, mobilization and the need for renal vein and hepatic vein re-implantation.

Feasibility of modified endarterectomized aortic allograft for middle hepatic vein reconstruction in living donor liver transplantation: A retrospective cohort study

BACKGROUND

Cryopreserved allografts and artificial vascular grafts were introduced to meet the increasing demand for adequate vascular substitutes for middle hepatic vein (MHV) reconstruction during living donor liver transplantation (LDLT). This study evaluated patency outcomes after engraftment of a modified endarterectomized aortic allograft (MEAA) without any additional patches.

METHODS

This retrospective double-arm study was conducted in single tertiary referral center between January 2015 and July 2018. Of 1,047 adult patients who underwent single-graft LDLT with a modified right lobe (MRL), 111 patients who received grafts with MHV reconstruction using MEAA were selected. The control group comprised 434 patients who underwent MHV reconstruction using iliac vein allografts. The main outcome measure was the short-term patency of the MEAA. The secondary outcome was the incidence of graft-associated complications.

RESULTS

Clinically significant MHV stenoses requiring stenting occurred in 3 patients (2.7%) in the MEAA group and in 17 patients (3.9%) in the iliac vein group (P = 0.778). Three-month and one-year patency rates on Doppler ultrasonography and computed tomography were 88.5% and 54.0%, respectively, in the MEAA group and 84.0% and 42.2%, respectively, in the iliac vein group, indicating the superior patency outcomes with MEAA (P = 0.017).

CONCLUSIONS

MHV reconstruction using MEAA during LDLT of a MRL graft is technically simple, achieves clinical outcomes comparable to iliac vein grafts, and is effective in expanding the allograft vessel pool for LDLT.

Imaging Evaluation of Living Liver Donor Candidates: Techniques, Protocols, and Anatomy

The need for liver transplants is increasing because the prevalence of liver diseases and the indications for transplants are growing. In response to the shortage of grafts from deceased donors, more transplants are being performed worldwide with grafts from living donors. Radiologic evaluation is an integral component in the assessment of donor candidates to ensure their eligibility and to choose the most appropriate surgical approach. MRI is the preferred modality for evaluation of the liver parenchyma and biliary tree. In most centers, a combination of MRI and CT is used to take advantage of the higher spatial resolution of CT for evaluation of arteries. However, MRI-only assessment is feasible. In addition to assessment of the liver parenchyma for abnormalities such as steatosis, a detailed evaluation of the hepatic vascular and biliary system for pertinent anatomic variants is crucial, because these variants can affect surgical techniques and outcomes in both recipients and donors. In this pictorial article, after a brief review of the most common surgical techniques and postsurgical liver anatomy, the biliary and vascular anatomy are discussed, with specific attention paid to the variants that are pertinent to this surgical procedure. The roles of liver segmentation and volumetric assessment and current imaging techniques and protocols are also discussed. Online supplemental material is available for this article. ©RSNA, 2021.

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.

Parietal Peritoneum as a Novel Substitute for Middle Hepatic Vein Reconstruction During Living Donor Liver Transplantation

BACKGROUND

Although autologous, cryopreserved, or artificial vascular grafts can be used as interpositional vascular substitutes for middle hepatic vein (MHV) reconstruction during living donor liver transplantation (LDLT), they are not always available, are limited in size and length, and are associated with risks of infection. This study aimed to evaluate the parietal peritoneum as a novel substitute for MHV reconstruction during LDLT.

METHODS

Prospectively collected data of 15 patients who underwent LDLT using the right liver with reconstruction of MHV using the recipients' own parietal peritoneum graft were retrospectively reviewed.

RESULTS

The 1-, 2-, 3-, and 5-mo patency rates were 57.1%, 57.1%, 57.1%, and 28.6%, respectively. Among the 15 cases assessed, the most recent 6 cases showed patent graft flow until discharge with 1-, 2-, 3-, and 5-mo patency rates of 80.0%, 80.0%, 80.0%, and 20.0%, respectively. All patients survived with tolerable liver function tests. There were no significant congestion-related problems, except for 1 patient who experienced MHV thrombosis requiring aspiration thrombectomy and stent insertion. There were no infection-related complications. All patients survived to the final follow-up, with a minimum follow-up duration of 8 mo. When comparing the latter 6 cases of peritoneal grafts and the recent 28 cases of conventional polytetrafluorethylene graft, the overall patency rate of the polytetrafluorethylene group was higher (P = 0.002). There were no major differences other than long-term patency rate.

CONCLUSIONS

Parietal peritoneum may be a novel autologous substitute for MHV reconstruction during LDLT.

Feasibility of using the homologous parietal peritoneum as a vascular substitute for venous reconstruction during abdominal surgery: An animal model

BACKGROUND

The interest in vascular substitutes has recently increased. We evaluated the feasibility of using a homologous parietal peritoneum as a vascular substitute for venous reconstruction during abdominal surgery.

METHODS

The inferior vena cava was replaced with a homologous parietal peritoneum after cross-linking with glutaraldehyde in 36 rabbits. At 7, 14, and 28 days, the patency rate, outer and inner graft diameters, histology, and immunohistochemistry were evaluated.

RESULTS

Both the 7- and 14-day groups maintained vascular patency. Vascular patency was maintained in 3 rabbits in the 28-day group. The inner diameters of the anastomotic sites were 6.23 ± 0.18, 5.64 ± 0.16, and 2.34 ± 0.21 mm in the 7-day, 14-day, and 28-day groups, respectively. The midpoint inner diameters of the homologous parietal peritoneum grafts were 624 ± 0.46, 5.74 ± 0.26, and 2.14 ± 0.28 mm in each group, respectively. Endothelial cell proliferation on the homologous parietal peritoneum graft surfaces in all groups was based on the histological findings from the first group. Multiple neovascularizations of the homologous parietal peritoneum graft were found in the 14- and 28-day groups, indicating neo-media formation. Acute inflammation appeared to progress to the entire layer of the homologous parietal peritoneum graft without an intraluminal thrombus, but the graft was patent in the 14-day group. In the 28-day group, 6 rabbits showed near-total occlusion and a thrombus formed in the homologous parietal peritoneum graft at the anastomosis site with severe stricture; however, the rabbits were alive and had collateral vessel formation.

CONCLUSION

Using homologous parietal peritoneum is feasible for venous reconstruction in abdominal surgery.

Investigation of a method for long-term preservation of the vascular allograft

BACKGROUND/OBJECTIVE

During multiple organ procurement, blood vessels are routinely retrieved and stored in University of Wisconsin solution and then discarded after two weeks, if not used at organ transplantation owing to lack of a method for long-term preservation. Therefore, the aim of this study is to investigate a method for long-term preservation of vascular allografts in ethanol.

METHODS

Aorta and vena cava allografts were retrieved and stored in 75% ethanol solution for 12 months at 4°C. Four pigs were divided into two groups. A segment of aorta was excised and replaced by insertion of preserved aorta graft (Group A) or vena cava graft (Group V). The pigs were observed for six weeks. A laparotomy was performed and the vascular graft was harvested for histopathology followed by euthanasia at the end of study.

RESULTS

Three pigs recovered uneventfully, while one pig died from venous graft rupture in the third week after surgery. There was no aneurysmal formation or thrombosis in the grafts. Some calcification was seen over aorta allograft. On histopathology, the elastic pattern was almost normal, although the endothelial cells degenerated after preservation. After implantation, the formation of the endothelium cell-like layer was seen in both aorta and vena cava allografts.

CONCLUSION

Vascular allografts were functional after preservation for 12 months. The vena cava grafts had much less wall calcification than the aorta grafts. Further studies are necessary to investigate vascular graft remodelling with a longer observation period after implantation.

Patency of Hemashield grafts versus ringed Gore-Tex grafts in middle hepatic vein reconstruction for living donor liver transplantation

Backgrounds/Aims

Owing to the short supply of homologous vein allografts, we previously used ringed Gore-Tex vascular grafts for middle hepatic vein (MHV) reconstruction in living donor liver transplantation. When ringed Gore-Tex grafts became unavailable, we used Hemashield vascular grafts. This study aimed to compare the patency and complication rates of Hemashield and ringed Gore-Tex grafts.

Methods

This retrospective two-arm study compared the study group that received Hemashield grafts (n=157) and the propensity score-matched control group that received ringed Gore-Tex grafts (n=157).

Results

In the Hemashield and Gore-Tex groups, the recipient age was 54.7±9.4 and 53.3±6.3 years; Model for End-stage Liver Disease scores were 15.9±9.2 and 16.9±8.3; and graft-recipient weight ratios were 1.07±0.24 and 1.10±0.23, respectively. In the Hemashield group, V5 reconstruction was performed using single (n=113, 72.0%), double (n=39, 24.8%), and triple (n=3, 1.9%) anastomoses. The proportion of double and triple anastomoses for V5 and V8 was higher in the Hemashield group than in the Gore-Tex group. Two (1.3%) patients required MHV conduit stenting owing to early thrombosis of the Hemashield graft. There was no difference in conduit occlusion- free patient survival rates between groups (p=0.91). The incidence of accidental conduit migration in the Hemashield and Gore-Tex groups was 0 (0%) and 2 (1.3%), respectively.

Conclusions

Hemashield grafts used in MHV reconstruction demonstrated acceptably high short- and mid-term patency rates, no incidences of conduit migration, easy handling, and good flexibility for length adjustment. Therefore, we suggest that the Hemashield graft is the preferentially suitable prosthetic material for MHV reconstruction.

Venous outflow reconstruction using a polytetrafluoroethylene (PTFE) graft in right lobe living donor liver transplantation: A single center study

BACKGROUND

Venous outflow reconstruction is very important especially in right lobe living donor liver transplantation without middle hepatic vein. Various interposition (venous or synthetic) grafts have been recommended for reconstruction of anterior sector tributaries.

METHODS

We aimed to describe our surgical technique and analyze anterior sector venous reconstruction using expanded polytetrafluroethylene graft. Retrospective analysis of prospectively collected data for 760 primary right lobe living donor liver transplantations performed at our institute between December 2011 and June 2018. Reconstruction of anterior sector: expanded polytetrafluroethylene (group A, n = 705) and autologous vein (group B, n = 55).

RESULTS

Pretransplant characteristics were comparable among both groups. Group A has significantly lower cold ischemia time (68.7 ± .3.5 minutes vs 127.8 ± 7.2 minutes; P < .001) and anhepatic time (116.3 ± 5.5 minutes vs 190.81 ± 9.35 minutes; P < .001) compared with group B. There was no difference in recovery pattern of liver functions, morbidity, and mortality between the 2 groups. One- and 6-month patency rates of interposition grafts were 97.6% and 84.4% (group A) and 96.4% and 78.1% (group B), respectively.

CONCLUSION

In centers with limited access to homologous or autologous vascular grafts, use of expanded polytetrafluroethylene graft for anterior sector venous outflow reconstruction in right lobe living donor liver transplantation is a viable option with excellent patency and patient outcomes.

Complications of polytetrafluoroethylene graft use in middle hepatic vein reconstruction in living donor liver transplantation: a retrospective, single-centre, long-term, real-world experience

In living donor liver transplantation (LDLT) of the right lobe, polytetrafluoroethylene (PTFE) grafts may be used for anterior drainage. This study aimed to determine the risk factors of PTFE graft-associated complications. Data from patients who underwent LDLT of the right lobe with middle hepatic vein reconstruction using PTFE grafts between January 2005 and December 2012 were retrospectively reviewed. Among 360 patients, PTFE graft-associated complications occurred in 17 patients (group B) (4.7%); recipients without these complications comprised group A (95.3%). The 1-, 6- and 12-month patency rates were significantly lower in group B (P < 0.001, P = 0.002 and P = 0.007). In group B, eight patients (47.1%) required surgical intervention, three patients (17.6%) suffered from infectious complications, and 14 patients (82.4%) experienced PTFE graft migration into the adjacent organs, namely the common bile duct (n = 3, 17.6%), stomach (n = 1, 5.9%), duodenum (n = 5, 29.4%) and jejunum (n = 5, 29.4%). The proportion of recipients who underwent hepaticojejunostomy, had abdominal adhesions and received interventions in/around the liver after LDLT was higher in group B (P < 0.001). Although the incidence of PTFE graft-associated complication is low, close long-term follow-up is needed, especially in patients with risk factors.

Modified Dual Hepatic Vein Anastomosis in Pediatric Living-Donor Liver Transplantation Using Left Lateral Segment Grafts With Two Wide Orifices

Background: The anatomic variation of hepatic vein in the left lateral segment (LLS) increases the risk of outflow complication in pediatric living liver transplantation (LDLT). Here, we share a modified method for dual hepatic vein reconstruction in pediatric LDLT using LLS with two wide orifices. Methods: From Sep 2018 to Dec 2019, 434 pediatric LDLTs using LLS were performed in our center. Hepatic veins of grafts were classified into three types with emphasis on the number, size, and location of orifices at the cut surface: a single opening (type I, n = 341, 78.57%); two adjacent orifices (type II, n = 66, 15.21%); two wide orifices with orifices distances <20 mm (type IIIa, n = 15, 3.46%); and two wide orifices with orifices distances >20 mm (type IIIb, n = 12, 2.76%). Rv was defined as the ratio of diameter of V2 and V3 (refer to hepatic vein drained segments II and III). We developed a modified dual hepatic vein anastomosis to reconstruct outflow for type IIIb grafts with Rv ≤1. Briefly, the hepatic vein of segment II was anastomosed to the common stump of middle hepatic vein (MHV) and left hepatic vein (LHV), followed by unification of V3 and the longitudinal incision orifice in inferior venous cave (IVC). Results: During median follow-up of 15.6 months (7.5-22.9 months), no hepatic vein complications occurred. Conclusion: This novel modified dual hepatic vein anastomosis could serve as a feasible surgical option for type IIIb LLS grafts with Rv ≤1 in pediatric LDLT.

Refined surgical techniques to improve the patency of cryopreserved iliac artery homografts for middle hepatic vein reconstruction during living donor liver transplantation

Purpose

A cryopreserved iliac artery homograft (IAH) has not been considered suitable for middle hepatic vein (MHV) reconstruction during living donor liver transplantation (LDLT), primarily due to the low patency from its small diameter. We revised our surgical techniques for MHV reconstruction using an IAH to improve its patency.

Methods

This study analyzed the causes of early conduit occlusion and developed revised techniques to address this that had clinical application.

Results

The potential risk factors for early conduit occlusion were the small IAH size, small graft in the segment V vein (V5) and segment VIII vein (V8) opening, and small recipient MHV-left hepatic vein stump. These factors were reflected to our revised surgical methods which included endarterectomy of the atherosclerotic plaque, unification of the internal and external iliac artery branches for large V5, and branch-patch arterioplasty for large V8. IAH endarterectomy, branch unification technique, and branch-patch arterioplasty were applied to 8, 5, and 5 patients, respectively and resulted in 1-month occlusion rates of 37.5%, 20.0%, and 40.0%, respectively. The overall patency rates of the IAH-MHV conduits in our 18 patients were 66.7% at 1 month, 38.9% at 3 months, and 33.3% at 1 year.

Conclusion

Our refined MHV reconstruction using an IAH improved short-term MHV conduit patency, but did not effectively prevent early conduit occlusion, particularly with a small- or medium-sized IAH. Individualized reconstruction designs during LDLT operation are needed when an IAH is used for a modified right liver graft.

Small-for-size graft, small-for-size syndrome and inflow modulation in living donor liver transplantation

The extended application of living donor liver transplantation (LDLT) has revealed the problem of graft size mismatching called "small-for-size syndrome (SFSS)." The initial trials to resolve this problem involved increasing the procured graft size, from left to right, and even extending to include a right lobe graft. Clinical cases of living right lobe donations have been reported since then, drawing attention to the risks of increasing the liver volume procured from a living donor. However, not only other modes of increasing graft volume (GV) such as auxiliary or dual liver transplantation, but also control of the increased portal pressure caused by a small-for-size graft (SFSG), such as a porto-systemic shunt or splenectomy and optimal outflow reconstruction, have been trialed with some positive results. To establish an effective strategy for transplanting SFSG and preventing SFSS, it is essential to have precise knowledge and tactics to evaluate graft quality and GV, when performing these LDLTs with portal pressure control and good venous outflow. Thus, we reviewed the updated literature on the pathogenesis of and strategies for using SFSG.

Hepatic vein in living donor liver transplantation

Right lobe living donor liver transplantation (LDLT) is a major development in adult LDLT that has significantly increased the donor pool by providing larger graft size and by decreasing risk of small-for-size graft syndrome. However, right lobe anatomy is complex, not only from the inflow but also from the outflow perspective. Outflow reconstruction is one of the key requirements of a successful LDLT and venous drainage of the liver graft is just as important as hepatic inflow for the integrity of graft function. Outflow complications may cause acute graft failure which is not always easy to diagnose. The right lobe graft consists of two sections and three hepatic venous routes for drainage that require reconstruction. In order to obtain a congestion free graft, several types of vascular conduits and postoperative interventions are needed to assure an adequate venous allograft drainage. This review described the anatomy, functional basis and the evolution of outflow reconstruction in right lobe LDLT.

Technical refinement of prosthetic vascular graft anastomosis to recipient inferior vena cava for secure middle hepatic vein reconstruction in living donor liver transplantation

Backgrounds/Aims

Hemashield vascular grafts has been used for middle hepatic vein (MHV) reconstruction during living donor liver transplantation (LDLT). We occasionally encounter outflow disturbance of MHV conduit at the anastomotic stump of the middle-left hepatic vein (MLHV) trunk. To mitigate the disturbance, we carried out a series of studies regarding hemodynamics-compliant MHV reconstruction.

Methods

This study comprised of three parts: Part 1: Determining the causes of outflow disturbance; Part 2: Computational simulative analysis; and, Part 3: Clinical application of our refined technique. The types of Hemashield conduit-MLHV stump reconstruction were end-to-end anastomosis (type 1), side-to- end anastomosis (type 2), and oblique cutting of the conduit end and patch plasty (type 3).

Results

In Part 1 study, the reconstruction types were type 1 in 23, type 2 in 25, and type 3 in 2. Significant anastomotic stenosis was identified in 7 (30.4%) in type 1, 6 (24.0%) in type 2, and none (0%) in type 3. The size of MLHV stump was the most important factor for anastomotic stenosis. Through Part 2 study, technical knacks were developed as follows: the conduit end was cut in a dumb-bell shape and a vessel patch attached; and then sutured bidirectionally from the 9 o’clock direction. In Part 3 study, these knacks were applied to 5 patients and none of them experienced noticeable anastomotic stenosis.

Conclusions

Our refined technique to perform conduit-MLHV stump anastomosis appears to reduce the risk of anastomotic outflow disturbance for relatively small MLHV stump.

Living-donor liver transplantation with inferior vena cava replacement in an infant recipient with advanced hepatoblastoma

Replacement of the inferior vena cava (IVC) after concurrent resection of hepatoblastoma-containing liver and retrohepatic IVC is regarded as a feasible option for pediatric living-donor liver transplantation (LDLT). This technique makes the extent of resection of LDLT comparable to that of deceased-donor liver transplantation (DDLT). We present one case of pediatric LDLT with IVC homograft replacement for advanced hepatoblastoma. The patient was a 10-kg 18-month-old girl suffering from large multiple hepatoblastomas, which were partially regressed by neoadjuvant chemotherapy. Because the tumors had invaded the retrohepatic IVC, there was a high risk of residual tumor cells at the IVC if it was preserved. Thus, we decided to replace the IVC during the LDLT operation. After a cold-stored fresh iliac vein homograft was prepared, we performed LDLT using her mother's left lateral section liver graft. A 4-cm-long common iliac vein homograft was attached to the liver graft at the back table. The left lateral-section graft with IVC attachment was implanted using the standard procedures like those of DDLT. We also did portal vein graft interposition. The patient recovered uneventfully and has been undergoing scheduled adjuvant chemotherapy to date. This is our second case of IVC homograft replacement for pediatric LDLT. In pediatric recipients, various vein homografts, such as iliac vein, IVC, and other large veins, can be used depending on the body size of the recipient and availability of vein homografts.

Impact of the Reconstruction Material on the Patency of Middle Hepatic Vein in Living Donor Liver Transplantation Using the Right Liver

BACKGROUND

A right liver graft with middle hepatic vein (MHV) reconstruction is the standard graft for adult-to-adult living donor liver transplantation (LDLT). The patency of reconstructed MHV affects the recovery and regeneration of graft. The aim of the study is to evaluate the patency rate of reconstructed MHV according to the reconstruction material in LDLT using the right liver.

METHODS

The data was collected retrospectively on 521 patients who underwent LDLT with right liver graft form August 2003 to December 2012 at the Seoul St. Mary's Hospital in Seoul. Two serial comparisons were performed. At first, patients were divided into 2 groups: biologic graft group (n = 252) and synthetic graft group (n = 177). Second, patients were divided into 6 groups: No MHV reconstruction (n = 92); MHV was reconstructed by greater saphenous vein (GSV) (n = 20); recipient's portal vein (PV) (n = 219); cryopreserved iliac artery (CIA) (n = 2); cryopreserved iliac vein (CIV) (n = 11); polytetrafluoroethylene (PTFE) graft (n = 105); and polyethylene terephthalate (PETE) graft (n = 72). We compared the patency of reconstructed MHV among these groups by computed tomography angiography at 7 days, 20 days, 90 days, and 1 year.

RESULTS

At the first comparison, the patency rate of the biologic graft group on the seventh postoperative day was 61.9%, and the synthetic graft group was 72.4% (P = .029). At postoperative 1 year, the patency rate of the biologic graft group was 42.9%, and the synthetic graft group was 24.1% (P = .001). At the second comparison, the MHV patency of GSV, PV, CIA, CIV, PTFE, and PETE was 65.0%, 62.5%, 50%, 63.6%, 75%, 72% on the seventh postoperative days (P = .318); 60%, 57.1%, 50%, 54.5%, 69%, 55.6% on the 20th postoperative days (P = .444); 40%, 48.8%, 50%, 27.3%, 47%, 34.1% on the 90th postoperative days (P = .294); and 30%, 45.2%, 50%, 27.3%, 27%, 26.4% at 1 postoperative year (P = .008).

CONCLUSION

Although there was no statistical difference in comparison of each material, there were significant differences in MHV patency rates between the biologic and the synthetic group. Therefore, the synthetic graft could be considered in living donor liver transplantation with MHV reconstruction.

Hemashield Vascular Graft Is a Preferable Prosthetic Graft for Middle Hepatic Vein Reconstruction in Living Donor Liver Transplantation

Background

Because of the supply shortage for homologous vein allografts, we previously used ringed Gore-Tex vascular grafts for middle hepatic vein (MHV) reconstruction in living donor liver transplantation. However, owing to the subsequent unavailability of ringed Gore-Tex grafts, we replaced them with Hemashield vascular grafts. This study aimed to compare the patency of Hemashield grafts with that of ringed Gore-Tex grafts.

Material/Methods

This was a retrospective double-arm study between the study group that used Hemashield grafts (n=63) and the historical control group that used ringed Gore-Tex grafts (n=126).

Results

In the Gore-Tex and Hemashield groups, mean age was 53.1±6.2 and 54.3±10.4 years; model for end-stage liver disease score was 16.5±8.3 and 17.5±9.9; and graft-recipient weight ratio was 1.11±0.23 and 1.12±0.25, respectively. In the Gore-Tex graft group, V5 reconstruction was done in single (n=107, 84.9%), double (n=17, 13.5%), and none (n=2, 1.6%). V8 reconstruction was done in single (n=95, 75.4%), double (n=1, 0.8%), and none (n=30, 23.8%). In the Hemashield group, V5 reconstruction was done in single (n=43, 68.3%), double (n=19, 30.2%), and triple (n=1, 1.6%). V8 reconstruction was done in single (n=45, 71.4%), double (n=9, 14.3%), and none (n=9, 14.3%). One-year conduit patency rates in the Gore-Tex and Hemashield groups were 54.8% and 71.6%, respectively (p=0.048).

Conclusions

MHV reconstruction using Hemashield vascular grafts demonstrated higher short-term patency rates than those associated with ringed Gore-Tex vascular grafts. We suggest that the Hemashield vascular graft is one of the best prosthetic materials for MHV reconstruction.

Reconstruction of Middle Hepatic Vein Tributaries With Artificial Vascular Grafts in Living Donor Liver Transplant Using Right Lobe Grafts: A Case Series

BACKGROUND

Congestion of the anterior section of the grafted liver might be a problem when performing living donor liver transplant using a right lobe graft without middle hepatic vein (MHV). This can be prevented by MHV tributary reconstruction. We report our procedure and results of reconstructing MHV tributaries using artificial vascular grafts (AVGs).

METHODS

We consider venous reconstruction when the estimated territory of each MHV tributary of the transplanted liver is more than 100 mL. For tributaries distant from the stump of the right hepatic vein of the graft, we use heparin-bonded AVGs made of expanded polytetrafluoroethylene with circular rings as the interposition graft between the MHV tributary and the inferior vena cava. During donor surgery, the suturing margin of the MHV tributary is secured before cutting, and it is anastomosed to the AVG during back-bench surgery. After restoration of portal flow in the recipient, we anastomose the AVG at a new position on the inferior vena cava.

RESULTS

The above procedure was performed for 4 cases. The estimated drainage territory of the vein that was reconstructed using the AVG ranged from 104 to 180 mL. The AVG patency was achieved for about 2 months in all cases. In terms of morbidity, biloma and pancreatic fistula were observed in 2 cases, although removal of the AVG was not required postoperatively in any of the cases.

CONCLUSION

The heparin-bonded expanded polytetrafluoroethylene AVG with circular rings is a feasible option for MHV tributary reconstruction in living donor liver transplant using right liver lobe grafts without MHVs.

Comparison of Patients With and Without Anterior Sector Venous Drainage in Right Lobe Liver Transplantation From Live Donors in Terms of Complications, Rejections, and Graft Survival: Single-Center Experience

AIM

The issue of performing an anastomosis of the anterior sector veins to the vena cava in living donor liver transplantation is still controversial. We aimed to research whether there was any difference in terms of complications, rejections, and graft survival between patients with and without anterior sector venous drainage to the vena cava.

PATIENTS AND METHODS

Patients were retrospectively investigated for demographic data and ratio of graft needed to available graft weight. Donors had volumetric calculations and middle hepatic vein anterior sector drainage documented in detail.

RESULTS

Seventy-three donors with middle hepatic vein drainage were included. Thirty-five had anterior sector venous drainage performed and 38 patients did not have drainage procedures performed. The incidence of general complications was higher in the group without anterior sector drainage (78.3% and P = .002). Biloma linked to bile leaks were observed in 8 patients without drainage (72.8%) and 3 patients with drainage (27.2%). Late acute rejection occurring during follow up after transplantation was identified in 28 patients (11.6%). Of these, 1 (14.3%) had anterior sector drainage and 6 (85.7%) were in the patient group without drainage (P = .067).

CONCLUSION

As a result of this study, for patients with grafts at the volume limit (graft weight to receiver weight ratio <0.8) and with congestion observed in the anterior sector after liver implantation and for patients with outflow problems identified on Doppler ultrasonography, anterior sector veins >5 mm should definitely be drained into the vena cava. Hence, both complication and rejection rates will reduce, and we can lengthen the graft, and thus patient, survival.

In Situ Split Liver Transplantation for 2 Adult Recipients: A Single-Center Experience

Background Material and Methods Results Conclusions.

Immunohistochemical evaluation for outflow reconstruction using opened round ligament in living donor right posterior sector graft liver transplantation: A case report

Utilizing the opened round ligament as venous grafts during liver transplantation is useful but controversial, and there are no pathological analyses of this procedure. Herein, we describe the first reported case of a pathological analysis of an opened round ligament used as a venous patch graft in a living donor liver transplantation (LDLT). A 13-year-old female patient with biliary atresia underwent LDLT using a posterior segment graft from her mother. The graft had two hepatic veins (HVs), which included the right HV (RHV; 15 mm) and the inferior RHV (IRHV; 20 mm). The graft RHV and IRHV were formed into a single orifice using the donor’s opened round ligament (60 mm × 20 mm) as a patch graft during bench surgery; it was then anastomosed end-to-side with the recipient inferior vena cava. The recipient had no post-transplant complications involving the HVs, but she died of septic shock with persistent cholangitis and jaundice 86 d after LDLT. The HV anastomotic site had no stenosis or thrombus on autopsy. On pathology, there was adequate patency and continuity between the recipient’s HV and the donor’s opened round ligament. In addition, the stains for CD31 and CD34 on the inner membrane of the opened round ligament were positive. Hepatic venous reconstruction using the opened round ligament as a venous patch graft is effective in LDLT, as observed on pathology.

Standardized surgical techniques for adult living donor liver transplantation using a modified right lobe graft: a video presentation from bench to reperfusion

After having experienced more than 2,000 cases of adult living donor liver transplantation (LDLT), we established the concepts of right liver graft standardization. Right liver graft standardization intends to provide hemodynamics-based and regeneration-compliant reconstruction of vascular inflow and outflow. Right liver graft standardization consists of the following components: Right hepatic vein reconstruction includes a combination of caudal-side deep incision and patch venoplasty of the graft right hepatic vein to remove the acute angle between the graft right hepatic vein and the inferior vena cava; middle hepatic vein reconstruction includes interposition of a uniform-shaped conduit with large-sized homologous or prosthetic grafts; if the inferior right hepatic vein is present, its reconstruction includes funneling and unification venoplasty for multiple short hepatic veins; if donor portal vein anomaly is present, its reconstruction includes conjoined unification venoplasty for two or more portal vein orifices. This video clip that shows the surgical technique from bench to reperfusion was a case presentation of adult LDLT using a modified right liver graft from the patient's son. Our intention behind proposing the concept of right liver graft standardization is that it can be universally applicable and may guarantee nearly the same outcomes regardless of the surgeon's experience. We believe that this reconstruction model would be primarily applied to a majority of adult LDLT cases.

Usability of Cryopreserved Aortic Allografts for Middle Hepatic Vein Reconstruction During Living-Donor Liver Transplantation

Iliac vein allografts are suitable for middle hepatic vein (MHV) reconstruction during living-donor liver transplantation (LDLT), but their supply is often limited. Polytetrafluoroethylene (PTFE) grafts are easily available but have drawbacks of accidental gastric penetration and non-degradable foreign body. To replace the use of PTFE grafts, we started using cryopreserved aorta allografts (CAAs). This study presents the technical details and patency outcomes of using CAAs in MHV reconstruction. We reviewed the surgical techniques of CAA interposition and analyzed the patency rates in 74 patients who underwent LDLT during the 6-year study period. The two control groups received either cryopreserved iliac veins (n = 122) or PTFE grafts (n = 84). The surgical techniques for MHV reconstruction used to implant the CAA and PTFE grafts are very similar because the techniques developed for PTFE grafts were also applied to CAAs. We inserted an arterial patch at the liver cut surface because the CAA wall is too thick to perform direct anastomosis. Two patients (2.7 %) underwent MHV stenting during the first month. The 1-year patency rate was 69.7 % in the CAA group vs. 39.2 % in iliac vein group vs. 57.2 % in PTFE group (p = 0.000). The overall graft and patient survival rates did not differ depending on the MHV interposition vessel materials (p > 0.1). CAAs combined with small-artery patches demonstrated high patency rates that surpass other vessel grafts, and thus, we suggest that CAA can be reliably used for MHV reconstruction when CAA is available.

Duodenal Penetration by the Ringed Expanded Polytetrafluoroethylene Graft for Middle Hepatic Vein Reconstruction During Living-Donor Liver Transplant: A Case Report

Expanded polytetrafluoroethylene grafts are widely used for middle hepatic vein reconstruction during living-donor liver transplant because they have comparable patency to autologous or cryopreserved vessels. Mechanical complications like gastric or duodenal penetration by expanded polytetrafluoroethylene grafts have been infrequently reported. We recently experienced a case of duodenal penetration by the expanded polytetrafluoroethylene graft. The patient was a 57-year-old man who had undergone a living-donor liver transplant for cryptogenic liver cirrhosis. At an annual follow-up computed tomography scan performed 3 years after transplant, the expanded polytetrafluoroethylene graft appeared to have penetrated into the first to the second portion of the duodenum, and abnormal air shadow and partial thrombus were identified within the expanded polytetrafluoroethylene graft. The patient underwent exploratory laparotomy, the expanded polytetrafluoroethylene graft was removed, and the perforated duodenum was repaired. Pyloric exclusion with gastrojejunostomy and feeding jejunostomy was additionally performed because of a wide defect in the duodenum. Adjacent organ injuries such as duodenal or gastric penetration by the expanded polytetrafluoroethylene graft after living-donor liver transplant is rare but not uncommon. Because the use of expanded polytetrafluoroethylene grafts is essential when an adequate vessel allograft is unavailable, we can consider transposition of the omental flap between the expanded polytetrafluoroethylene graft and the stomach or duodenum to reduce this unexpected complication.

Venous outflow reconstruction in living donor liver transplantation: Dealing with venous anomalies

The reconstruction of the vascular outflow tract of partial liver grafts has received considerable attention in the past, especially in the setting of right liver grafts with undrained segments. Hepatic venous outflow reconstruction is an important factor for successful living donor liver transplantation outcome. However, in presence of undrained anterior sector and presence of multiple short hepatic veins that drain substantial portions of liver, outflow reconstruction without backtable venoplasty may lead to severe graft congestion and subsequent graft dysfunction. Various backtable venoplasty techniques in presence of multiple hepatic veins that can be used in either right- or left-lobe liver transplantation are devised to ensure a single, wide outflow channel. In this overview, various techniques to overcome the hepatic venous variations of liver allograft and outflow reconstruction are discussed.

Technical options for outflow reconstruction in domino liver transplantation: A single European center experience

Venous outflow is critical to the success of liver transplantation (LT). In domino liver transplantation (DLT), the venous cuffs should be shared between the donor and the recipient, and the length can be compromised. The aim of this study was to describe and compare the technical options for outflow reconstruction used at our institution. This was a retrospective analysis of 39 consecutive DLT recipients between January 1997 and May 2013. Twenty-seven men and 12 women (mean age, 61.8 ± 4.3 years) underwent LT and consented to receive a liver from a donor with familial amyloid polyneuropathy (FAP). The main indications were hepatocellular carcinoma and hepatitis C virus cirrhosis. All recipients underwent transplantation by a piggyback technique. Liver procurement in the FAP donors was performed with the classic technique in 22 patients and with the piggyback technique in the last 17. In these latter cases, for vascular outflow reconstruction, a cadaveric venous graft was interposed between the hepatic vein (HV) stump of the FAP liver and the recipient HV in 11 cases (28%). Since 2011, we have employed arterial grafts to be interposed between the vessels stumps: a tailored arterial graft in 5 patients and an aortic graft in 1 case. There was no postoperative mortality. Arterial and portal complications presented in 2 (5.1) and 4 patients (10.3), respectively. Postoperative outflow complications (post-LT subacute Budd-Chiari syndrome) occurred in 4 patients, and all of them had received a venous interposed graft for reconstruction. The incidence of outflow complications tended to be higher among patients with venous grafts than those with arterial graft interposition. Overall patient survival at 1, 3, 5, and 10 years was 97%, 79%, respectively. Arterial grafts constitute a feasible and safe option for vascular outflow reconstruction in DLT because they are associated with a relatively low incidence of complications. The recently proposed Bellvitge arterial graft technique should be added to the current range of available surgical modalities.

Cryopreserved arterial grafts as a conduit in outflow reconstruction in living donor liver transplantation

BACKGROUND

Few reports have addressed the use of cryopreserved arterial grafts (CAG) for anterior section drainage in right lobe living donor liver transplantation (RL LDLT), and the impact of atherosclerosis on patency rate (PR) is not well studied. Also, those reports have limited case numbers. The aim of the present study is to report the largest experience with CAG in outflow reconstruction in RL LDLT and the impact of atherosclerosis on its patency.

METHODS

During 2010 and 2011, 62 of 243 patients who underwent LDLT received outflow reconstruction with CAG for RL grafts. Atherosclerosis in CAG was classified into early, intermediate and advanced lesions according to the classification adopted by the American Heart Association: group 1 with grafts having no atherosclerosis or early lesions; and group 2 with grafts having intermediate and advanced lesions. Patency rates of CAG correlated with atherosclerotic change of CAG were retrospectively analyzed.

RESULTS

The study group comprised 65 CAGs with 1, 3 and 6 months PR of 86.2%, 84.6% and 75.2% respectively. Histopathological examination was successful in 53 CAGs. The 1, 3 and 6 months PR of group with no/early atherosclerosis were 86%, 83.7% and 76.7%, respectively, while for groups with intermediate/advanced lesions they were 90%. However, there was no significant difference between the two groups (P = 0.384).

CONCLUSIONS

Cryopreserved arterial grafts can be used for outflow reconstruction in RL LDLT with a good patency rate. Atherosclerosis appears to have minimal effect on CAG patency, yet further studies with larger cohorts are needed to support our results.

Outflow reconstruction with arterial patch in domino liver transplantation: a new technical option

Domino liver transplantation (LT), using livers from familial amyloidotic polyneuropathy (FAP) patients, is a well described technique useful to expand donor pool. One of the main difficulties of this type of LT arises from the necessity to share the vascular pedicles between the graft and the donor. The most important challenge resides in restoring a proper hepatic venous outflow in the FAP-liver recipient. This is specially challenging when using the piggy-back technique, because the hepatic stumps may be too short. To overcome this issue, surgeons explored several techniques using different types of venous grafts. We describe a new technical option by using an arterial graft from the deceased donor. By using both iliac arteries a long graft is created and sutured as needed to the hepatic vein stump. We describe herein this new technique employed in a domino liver recipient who underwent retransplantation for ischemic cholangitis. The procedure was performed using the piggy-back technique; the venous stump of the FAP liver was reconstructed with the arterial graft. The patient had uneventful postoperative and mid-term hepatic function, and anastomosis was patent 24 months after LT.

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.

Banking of cryopreserved iliac artery and vein homografts: clinical uses in transplantation

Iliac artery and vein homografts are critical for revascularization in living-donor liver transplantation. Since 2010, National Cardiovascular Homograft Bank and National University Hospital have collaborated in the pioneer endeavor of banking iliac vessel homografts for such surgeries in Singapore. This article aims to demonstrate that the processing, decontamination and cryopreservation techniques that our bank follow, help preserve iliac vessel homografts for a longer duration as compared to homografts preserved using short-term preservation techniques. This paper reports the first 4 years of post-operative outcome for recipients as a preliminary report for a longer-term outcome study. Criteria for donor assessment, techniques of iliac vessel homograft recovery, processing, decontamination, cryopreservation and storage according to the American Association of Tissue Banks standards are also described. From 2010 until 2013, we discovered of the iliac vessel homografts processed, 17 (94.4 %) were suitable for clinical use. Nine iliac artery grafts (64 %) and one iliac vein graft (14 %) were implanted. Irrespective of vessel type, homografts <90 mm in length were of little use. Of the nine current iliac vessel homograft recipients, eight patients (89 %) had living-donor liver transplantation and one patient (11 %) had reconstruction of the right internal carotid artery after resection of an aneurysm. Our preliminary results supports existing literatures that suggest cryopreserved iliac vessel homografts can be successfully used for revascularization in liver transplantation and reconstruction of carotid artery. Encouraging short-term post-operative patient outcomes have been achieved, with no report of adverse event attributed to implanted homografts. We believe that our processing, decontamination and cryopreservation techniques have helped preserve the homografts for longer duration as compared to homografts preserved using short-term preservation techniques.

Calcification of Cryopreserved Arterial Graft Causing Delayed Obstruction of Portal Vein Flow After Liver Transplant

In patients with biliary atresia, portal vein problems may cause challenges for liver transplant. Interposition grafts have been used for vascular anastomoses in transplant recipients with varied success. A cryopreserved iliac artery graft was used for the reconstruction of the portal vein in a 29-month-old infant with biliary atresia. At 17 months after transplant, she developed upper gastrointestinal bleeding that was caused by portal vein occlusion because of vascular calcifications in the graft. Upper gastrointestinal endoscopy showed esophageal varices with fresh bleeding, and the varices were band ligated. At 3 months after the bleeding episode, the patient was asymptomatic and biochemical tests were normal. In summary, liver transplant with cryopreserved iliac artery graft may be complicated by calcifications and portal vein occlusion, and caution is advised in using this graft material for portal vein anastomoses.

Outcomes of long storage times for cryopreserved vascular grafts in outflow reconstruction in living donor liver transplantation

The outflow reconstruction of the right anterior sector in a right liver graft (RLG) with cryopreserved vascular grafts (CVGs) is crucial for preventing graft congestion in living donor liver transplantation (LDLT). The impact of the duration of cryopreservation has not been evaluated so far. From 2006 to 2009, 250 LDLT were performed: 47 of these patients (group 1) received CVGs stored for ≦1 year, and 33 patients (group 2) received CVGs stored for >1 year. Single or multiple segment 8 hepatic veins were reconstructed. The number of anastomoses did not affect vascular graft patency (P = 0.21). The length of the cryopreservation time did not affect the histological findings for CVGs. The preoperative and postoperative liver graft volumes were 783.8 ± 129.7 and 1102 ± 194.7 cc, respectively, for group 1 and 753.7 ± 158.5 and 1097.2 ± 178.7 cc, respectively, for group 2. The regeneration indices for liver grafts in the whole patient group, group 1, and group 2 were 48.9%, 47.4%, and 51.05%, respectively. In conclusion, the storage duration has no impact on the patency of CVGs in outflow reconstruction or on the regeneration of RLGs in LDLT. CVGs stored for >1 year can be safely used for the outflow reconstruction of RLGs in LDLT.

Vascular reconstruction combined with liver resection for malignant tumours

BACKGROUND

The resectability criteria for malignant liver tumours have expanded during the past two decades. The use of vascular reconstruction after hepatectomy has been integral in this process. However, the majority of reports are anecdotal. This is a retrospective analysis of the techniques, morbidity, mortality and risk factors of liver resections with vascular reconstruction based on a large series from a single centre.

METHODS

Patients who underwent hepatic resection combined with vascular resection and reconstruction between 1997 and 2009 were included in this study. Indications for surgery, morbidity and 90-day mortality are reported along with factors predictive of operative mortality.

RESULTS

Eighty-four patients had liver resection with 97 vascular resections and reconstruction. There were 44 men and 40 women with a mean(s.d.) age of 56·9(12·1) years. Mean(s.d.) follow-up was 37·3(34·1) months. All patients had primary or metastatic liver tumours. The perioperative morbidity rate was 62 per cent (52 patients) and the operative mortality rate 14 per cent (12). Predictors of operative mortality were: bilirubin level exceeding 34 µmol/ml (P = 0·023), indocyanine green retention rate at 15 min over 10 per cent (P = 0·031), duration of ischaemia (P = 0·011), amount of blood transfused (P = 0·025) and combined major extrahepatic procedure (P = 0·042). Actuarial 3- and 5-year survival rates were 44 and 26 per cent respectively.

CONCLUSION

Liver resection with combined vascular resection and reconstruction can be performed in selected patients with acceptable morbidity and mortality. The lack of therapeutic alternatives and the poor outcome of non-operative management seem to justify this approach. The identification of risk factors should help improve patient selection and postoperative outcome as well as facilitate objective risk communication with surgical candidates.

Living-donor liver transplant using the right hepatic lobe without the right hepatic vein: solving the drainage problem

Although rare, major congenital defects of the hepatic veins are detectable at autopsy, advanced, noninvasive imaging techniques such as Doppler ultrasonography and multislice computed tomography can accurately define these anomalies. One of these anomalies is congenital absence of the main right hepatic vein. We present a 21-year-old woman living-liver donor candidate with congenital absence of the right hepatic vein who underwent an extended right donor hepatectomy. She was tested for transplant compatibility with her 45-year-old brother, who had chronic liver failure secondary to hepatitis B. Multislice computed tomography revealed an absence of the right hepatic vein, and the right hepatic lobe was drained by 4 inferior hepatic veins with diameters ranging from 4 to 8.4 mm. An extended right-donor hepatectomy was performed. A common-large opening drainage reconstruction model that included all of the inferior hepatic veins and middle hepatic vein was created using the saphenous vein and an aortic homograft. There were no postoperative complications related to hepatic venous drainage thanks to the common-large opening model. We demonstrate that a right donor hepatectomy is feasible in congenital absence of the right hepatic vein solving the drainage problem using common-large opening reconstruction technique.

Storage of allogeneic vascular grafts: experience from a high-volume liver transplant institute

Allogeneic vascular grafts are often required for vascular reconstruction during living donor liver transplantation. Such grafts are obtained prior to use, making storage conditions a critical issue for maintaining the integrity of the tissue to ensure a successful transplantation. This study describes an optimized storage protocol currently in use at a high-volume liver transplant center. Twenty-nine allogeneic vascular graft tissues obtained during cardiovascular surgery or from cadaveric donors were stored respectively in sterile 50 mL of Ringer lactate solution, without any preservation solutions or antimicrobials, at -22°C for a maximum of 3 months. Prior to use in vascular reconstruction, grafts were thawed in 0.9% NaCl solution at 37°C, and 1 × 0.5-cm(2) tissue samples were collected for microbial culturing and viral serology. ABO compatibility was not performed for any patients receiving vascular grafts. During this prospective study, all 29 allogeneic vascular grafts were used for back-table vascular reconstruction in living donor liver transplantation procedures. A total of 16 grafts were from the saphenous vein, 10 were from the iliac vein, and 3 were from the iliac artery. Bacterial growth was not detected in any tissue samples taken from the stored grafts. No vascular graft-related complications occurred during the 5 months of follow-up. The successful vascular reconstructions achieved with all 29 study grafts demonstrate that the simple, inexpensive storage method described herein is feasible and safe. Randomized, controlled studies should be carried out to further optimize and standardize the technique.

Diagnosis and management of abdominal vascular injuries

Intra-abdominal vascular trauma is an injury that continues to challenge the general surgeon and leads to high morbidity and mortality even at busy urban trauma centers. The majority of patients arrive in hemorrhagic shock; therefore, rapid evaluation, resuscitation, and transfer to the operating room are necessary to treat these patients. In the operating room, the surgeon must have a well-planned surgical approach to the variety of potential injuries encountered in the retroperitoneal space. This article reviews the incidence, diagnostic strategies, treatment principles, and expected outcomes when dealing with intra-abdominal vascular injury.

Usability of ringed polytetrafluoroethylene grafts for middle hepatic vein reconstruction during living donor liver transplantation

Large vein allografts are suitable for middle hepatic vein (MHV) reconstruction, but their supply is often limited. Although polytetrafluoroethylene (PTFE) grafts are unlimitedly available, their long-term patency is relatively poor. We intended to enhance the clinical usability of PTFE grafts for MHV reconstruction during living donor liver transplantation (LDLT). Two sequential studies were performed. First, PTFE grafts were implanted as inferior vena cava replacements into dogs. Second, in a 1-year prospective clinical trial of 262 adults undergoing LDLT with a modified right lobe, MHV reconstruction with PTFE grafts was compared with other types of reconstruction, and the outcomes were evaluated. In the animal study, PTFE grafts induced strong inflammatory reactions and luminal thrombus formation, but the endothelial lining was well developed. In the clinical study, the reconstruction techniques were revised to make a composite PTFE graft with an artery patch on the basis of the results of the animal study. MHVs were reconstructed with cryopreserved iliac veins (n = 122), iliac arteries (n = 43), aortas (n = 13), and PTFE (n = 84), and these reconstructions yielded 6-month patency rates of 75.3%, 35.2%, 92.3%, and 76.6%, respectively. The overall 6-month patency rates for the iliac vein and PTFE grafts were similar (P = 0.92), but the 6-month patency rates with vein segment 5 were 51.0% and 34.7%, respectively (P = 0.001). The overall graft and patient survival rates did not differ among these 4 groups. In conclusion, ringed PTFE grafts combined with small vessel patches showed high patency rates comparable to those of iliac vein grafts; thus, they can be used for MHV reconstruction when other sizable vessel allografts are not available.