Meso-Rex bypass as an alternative technique for portal vein reconstruction at or after liver transplantation in children: review and perspectives

Effectiveness of Preoperative Intrahepatic Portal Venous Classification System in Guiding Preoperative Surgical Decisions and Predicting Hypotensive Effects After Meso-rex Bypass for Children With EHPVO

BACKGROUND

The categorization of intrahepatic portal venous system (IHPS) patterns using wedged hepatic venous portography (WHVP) has proven to be an effective tool in the preoperative evaluation of Rex recessus and in identifying pediatric patients with extrahepatic portal vein obstruction (EHPVO) who are suitable for meso-Rex bypass (MRB). Despite this classification system being proposed a decade ago, its clinical application remains underutilized.

METHODS

A single-center retrospective study of 182 children with EHPVO was conducted between October 2014 and July 2023 when MRB was attempted. Data on demographics, etiology, imaging examinations, procedures, and follow-up were collected for 161 patients included. Two interventional radiologists used deVille's method to classify patients into types A to E based on WHVP imaging, with interobserver agreement analyzed. Associations between IHPS patterns and surgical outcomes following MRB were investigated.

RESULTS

Two radiologists had a high level of agreement on identifying IHPS patterns and suitable patients for MRB. Of the 161 cases, 130 were type A, 10 were type B, 5 were type C, 7 were type D, and 9 were type E. One hundred and forty-five patients with types A, B and C underwent successful MRB, showing feasibility for 90% of patients. Children categorized as types A and B experienced more significant benefits than type C, including intraoperatively decreased portal vein pressure, esophageal/gastric varices relief, decreased portal venous collaterals and a lower rate of bypass occlusion after one year. The surgical outcomes of patients with types A and B were not influenced by the diameter of the Rex recessus as suggested by WHVP.

CONCLUSIONS

The majority of pediatric patients with EHPVO in mainland China have opportunities to receive successful MRB. There are potential differences in the etiology of Chinese and Western patients. The IHPS classification system aids in guiding preoperative surgical decisions and predicting hypotensive effects after MRB. Type C patients should be carefully chosen for MRB.

Recanalization of portal vein thrombosis after pediatric liver transplantation: Efficacy and safety of the transsplenic access

BACKGROUND

Endovascular management of portal vein thrombosis (PVT) is challenging. Transsplenic access (TSA) is growing as an access option to the portal system but with higher rates of bleeding complications. The aim of this article is to evaluate the efficacy and safety of transsplenic portal vein recanalization (PVR) using a metallic stent after pediatric liver transplantation.

MATERIALS AND METHODS

This is a retrospective review of 15 patients with chronic PVT who underwent PVR via TSA between February 2016 and December 2020. Two children who had undergone catheterization of a mesenteric vein tributary by minilaparotomy were excluded from the patency analysis but included in the splenic access analysis. The technical and clinical success of PVR and complications related to the procedure via TSA were evaluated.

RESULTS

Thirteen children with PVT were treated primarily using the TSA. The mean age was 4.1 years (range, 1.5-13.7 years), and the most common clinical presentation was hypersplenism (60%). Technically successful PVR was performed in 11/13 (84.6%) children, and clinical success was achieved in 9/11 (81.8%) children. No major complications were observed, and one child presented moderate pain in the TSA (from a total of 17 TSA). The median follow-up was 48.2 months. The median primary patency was 9.9 months. Primary patency in the first 4 years was 75%, and primary assisted patency was 100% in the follow-up period.

CONCLUSIONS

Transsplenic PVR is a safe and effective method for the treatment of PVT after pediatric liver transplantation.

The Role of Imaging in Portal Vein Thrombosis: From the Diagnosis to the Interventional Radiological Management

PURPOSE

To illustrate diagnostic and interventional imaging for the characterization and treatment of portal vein thrombosis (PVT).

INTRODUCTION

The broad spectrum of congenital and acquired PVT manifestations is illustrated, with a focus on the pediatric population; diagnostic and interventional imaging techniques are described.

DESCRIPTION

PVT frequently presents as an incidental finding at imaging in the screening for liver diseases or for other unrelated reasons. PVT can be classified based on: extension (intrahepatic, extrahepatic, involving the spleno-mesenteric tract, etc.); degree (partial or complete); onset (acute or chronic); and with or without cavernomatous transformation. This comprehensive review relies on the experience gained from a large series of congenital and acquired PVT in a referral center for pediatric and adult liver transplantation. Diagnostic and interventional imaging techniques are described, including: color-Doppler and contrast-enhanced Ultrasound; CT and MR angiography; retrograde portography; percutaneous transhepatic, transplenic, and transmesenteric portography; transjugular intrahepatic portosystemic shunt creation. Pre- and post-operative imaging assessment of the surgical meso-rex bypass is discussed. The description is enriched with an original series of pictorial imaging findings.

CONCLUSION

PVT is a clinical condition associated with significant morbidity and mortality. Diagnostic and interventional imaging plays a crucial role in both conservative and operative management.

Portal vein reconstruction with cryopreserved vascular grafts: A two-edged sword

BACKGROUND

Portal vein anastomotic complications related to size discrepancy are important causes of morbidity and mortality in pediatric liver transplantation. Interposed vascular grafts in portal vein anastomosis can solve this problem. The aim of this study is to evaluate the results of pediatric liver transplantations performed using cryopreserved interposed vascular grafts between graft portal vein and superior mesenteric vein (SMV)-splenic vein (SpV) confluence.

METHODS

Twenty-nine pediatric patients received liver transplantation using cryopreserved venous grafts in our Liver Transplant Institute between 2013 and 2020 were included in this study. Demographic, clinical, and operative characteristics and postoperative follow-up were analyzed.

RESULTS

Sixteen patients (55.2%) had portal hypoplasia and five patients (17.2%) had portal vein thrombosis. In total, six patients (20.6%) suffered portal vein thrombosis in the early postoperative period. Three patients (10.3%) experienced portal vein thrombosis in the late postoperative period. Late portal vein thrombosis rate was significantly higher in patients with early portal vein thrombosis (3/6 patients [50%] versus 0/23 patients [0%]; p = .034). Lack of portal flow was significantly higher in patients with both early (50% versus 0%; p = .002) and late portal vein thrombosis (66.7% versus 6.7%; p = .03).

CONCLUSION

Preoperative portal vein thrombosis and insufficient flow are important factors affecting success of liver transplant in children. The use of interposed vein grafts in problematic portal anastomoses can overcome portal flow problems.

Technical Aspects and Considerations of Meso-Rex Bypass Following Liver Transplantation With Left Lateral Segment Grafts: Case Report and Review of the Literature

In pediatric patients with extrahepatic portal vein obstruction and complications of portal hypertension, but with normal liver function, a meso-Rex bypass (MRB) connecting the superior mesenteric vein to the intrahepatic left portal is the favored surgical management. Pediatric patients with a history of a partial liver transplant (LT), especially living donors, are at greater risk for portal vein complications. Hence, an adequate knowledge of this technique and its additional challenges in the post-LT patient setting is crucial. We provide an overview of the available literature on technical aspects for an MRB post-LT. Preoperative considerations are highlighted, along with intraoperative considerations and postoperative management. Special attention is given to the even-more-demanding aspect of performing an MRB post-liver transplantation with a left lateral segment. Surgical alternatives are also discussed. In addition, we report here a unique case in which this surgical technique was performed on a complex pediatric patient with a history of a living-donor LT with a left lateral segment graft over a decade ago.

Modified Meso-Rex bypass with umbilical vein recanalization and intra-operative stenting

PURPOSE

The aim of the study was to evaluate the usefulness of a novel modified Meso-Rex bypass surgical technique with umbilical vein recanalization and intra-operative stenting to treat portal vein cavernous transformation.

METHODS

In total, 13 portal vein cavernous transformation patients underwent Meso-Rex bypass surgery, consisting of bypass grafts between the superior mesenteric vein (SMV) and the recess of Rex as well as through the ligamentum teres hepatis without stent implantation (Group A, n = 9) and umbilical vein recanalization with intra-operative stent implantation (Group B, n = 4).

RESULTS

In Group A, the bypass diameter was 0-6 mm (median 3 mm) and blood flow velocity 25-115 cm/s (median 72 cm/s) 1 month after Meso-Rex bypass surgery, with open bypass times of 0-67 months (median 6 months); 6 patients in this group developed postoperative Meso-Rex bypass occlusions. A patient in Group A treated with ligamentum teres hepatis recanalization needed a thrombectomy and stent implantation during a second surgery 2 days after the Meso-Rex bypass, because of bypass thrombosis and umbilical vein stenosis. In Group B, the average modified Meso-Rex bypass diameter was 5.5-6.5 mm (median 6 mm), and the bypass vessels remained open in all patients, with blood flow rates of 45-100 cm/s (median 76.5 cm/s) 1 month after the modified Meso-Rex bypass, up to the endpoint (15-33 months, median 24 months). The rate of bypass occlusions in Group A and Group B were 22.2% and 0%, 30.0% and 0%, and 55.6% and 0% at 1 month, 3 months, and 1 year, respectively, after bypass surgery.

CONCLUSIONS

Our novel modified Meso-Rex bypass approach for portal vein cavernous transformation treatment was effective with excellent long-term bypass patency.

Portal vein obstruction after pediatric liver transplantation: A systematic review of current treatment strategies

INTRODUCTION

Portal vein obstruction (PVO) is a significant vascular complication after liver transplantation (LT) in pediatric patients. Current treatment strategies include percutaneous transluminal angioplasty (PTA), with or without stent placement, mesorex bypass (MRB), splenorenal shunt, mesocaval shunt, endovascular recanalization (EVR), splenic artery embolization and splenectomy. However, specific characteristics of patients undergoing intervention and selection of individual treatment and its efficacy have remained unclear. This review systematically analyzed biochemical and clinical characteristics, selection of treatment, efficacy, and post-procedural complications.

METHODS

We systematically searched PubMed and Embase between January 1995 and March 2021 for studies on the management of PVO after LT. We analyzed the reports for biochemical and clinical characteristics at the timing of the intervention in different patients, selection of treatment, and reported efficacies.

RESULTS

We found 22 cohort studies with 362 patients who had the following characteristics: biliary atresia (83%), living-donor LT (85%), thrombocytopenia (73%), splenomegaly (40%), ascites (16%), or gastrointestinal bleeding (26%). The 3-year primary patency of PTA without stent placement was similar to that with stent placement (70%-80% and 43%-94%, respectively). MRB was used as an initial treatment with a 3-year patency of 75% to 100%. One study showed that 5-year primary patency of EVR was 80%. Secondary patency was 90% to 100% after 3 years in all studies with PTA alone, PTA/stent placement, and stent placement alone.

CONCLUSION

This is the first review of all treatment protocols in PVO after pediatric LT. We showed that an important group of patients has severe symptoms of portal hypertension. Efficacy of all treatment modalities was high in the included studies which make them important modalities for these patients.

Outcomes of Liver Transplantation in Small Infants

Liver transplantation (LT) for small infants remains challenging because of the demands related to graft selection, surgical technique, and perioperative management. The aim of this study was to evaluate the short-term and longterm outcomes of LT regarding vascular/biliary complications, renal function, growth, and patient/graft survival in infants ≤3 months compared with those of an age between >3 and 6 months at a single transplant center. A total of 64 infants ≤6 months underwent LT and were divided into 2 groups according to age at LT: those of age ≤3 months (range, 6-118 days; XS group, n = 37) and those of age >3 to ≤6 months (range, 124-179 days; S group, n = 27) between 1989 and 2014. Acute liver failure was the main indication for LT in the XS group (n = 31, 84%) versus S (n = 7, 26%). The overall incidence of hepatic artery thrombosis and portal vein thrombosis/stricture were 5.4% and 10.8% in the XS group and 7.4% and 11.1% in the S group, respectively (not significant). The overall incidence of biliary stricture and leakage were 5.4% and 2.7% in the XS group and 3.7% and 3.7% in the S group, respectively (not significant). There was no significant difference between the 2 groups in terms of renal function. No significant difference was found between the 2 groups for each year after LT in terms of height and weight z score. The 1-, 5-, and 10-year patient survival rates were 70.3%, 70.3%, and 70.3% in the XS group compared with 92.6%, 88.9%, and 88.9% in the S group, respectively (not significant). In conclusion, LT for smaller infants has acceptable outcomes despite the challenges of surgical technique, including vascular reconstruction and graft preparation, and perioperative management.

Unusual venous collateral pathways allow for reperfusion of the intrahepatic portal venous system in children with portal vein thrombosis after split liver transplantation: Clinical relevance and management implications

PVT is the most frequent vascular complication after LT in small children, and a higher incidence has been observed in those transplanted for biliary atresia or with a LLSG. Thrombosis of the PV causes extrahepatic portal hypertension and is associated with splenomegaly and the development of venous neo-collaterals, including gastro-oesophageal varices and splenorenal shunts. It has also been incidentally suggested in the literature that patients who have had a Roux-en-Y loop for a biliary reconstruction may present with a cavernomatous transformation of the distal portion of the loop. In this study, 13 children with CEPH caused by thrombosis of the PV after LT were analysed. The study evidenced the development of two types of hepatopetal venous networks: (a) a large cavernoma along the Roux loop and around the biliary anastomosis, and (b) a network of neo-collaterals in the gastro-duodeno-pancreatic area that connected to the intrahepatic portal branches directly through the liver capsule. These hepatopetal venous networks between the venous system of the surrounding organs or the omentum and the intrahepatic portal branches can be identified by radiologists. The relevance for the transplanting physician and the transplant surgeon is discussed.

Multimodality imaging of the Meso-Rex bypass

Extrahepatic portal vein obstruction (EHPVO) is the most common cause of upper gastrointestinal bleeding in children. It is defined as thrombosis of the extrahepatic portal vein with or without extension to the intrahepatic portal veins. The Meso-Rex shunt is the gold standard treatment in children with favorable anatomy since it restores physiological portal liver reperfusion. This is achieved by rerouting the splanchnic venous blood through an autologous graft from the superior mesenteric vein (SMV) into the Rex recess of the left portal vein, curing portal hypertension by doing so. General and hepatobiliary radiologists must be familiar with multimodality imaging appearances of EHPVO and with the role of imaging in identifying suitable candidates for Meso-Rex bypass surgery. Imaging might also detect complications of this procedure, some of which might be treated via interventional radiology.

Aggressive prevention and preemptive management of vascular complications after pediatric liver transplantation: A major impact on graft survival and long-term outcome

Vascular complications are a major cause of patient and graft loss after LTs. The aim of this study was to evaluate the effect of a multimodal perioperative strategy aimed at reducing the incidence of vascular complications. A total of 126 first isolated LTs-performed between November 2008 and December 2015-were retrospectively analyzed. A minimum follow-up period of 24 months was analyzable for 124/126 patients (98.4%). The aggressive preemptive strategy consisted of identifying and immediately managing any problem and any abnormality in the vascular flow, in any of the hepatic vessels, and at any time after the liver graft revascularization. As a result, with a median follow-up of 57 months (3-112 months), not a single graft has been lost from vascular or biliary problems. The actuarial 8-year graft survival is 96.5%. These results have shown that a combination of technical attention, medical prevention, an early diagnosis, and rapid interventions reduced the negative impact of vascular problems on the outcome of both grafts and patients.

Enlarging vascular stents after pediatric liver transplantation

BACKGROUND

Endovascular intervention with stent placement to treat portal vein (PV) and hepatic vein (HV) stenosis after pediatric liver transplantation (LT) is still controversial in small children owing to the potential risk of functional stenosis after growth. The aim of this study is to evaluate the safety and efficacy of stent placement in this population.

METHODS

Between 2004 and 2016, 6 children (all <3 years) received HV (n = 2) and PV (n = 4) stents placement among 46 pediatric LT patients at our institution. The clinical outcome and patency rate were followed. Morphologic changes of stents were assessed from plain films by a new index: the stent diameter ratio (SDR).

RESULTS

The median age of the patients at LT was 8.9 months. The patency rate was 100% without functional stenosis during a median follow-up period of 65.5 months. The "stent growth" phenomenon was demonstrated by SDR with significant resolution of hourglass deformity 2 years after stent placement (p for trend <.001).

CONCLUSION

Vascular stent placement is a safe and effective method for the management of PV and HV stenosis following pediatric LT because these stents will enlarge as children grow.

TYPE OF STUDY

Case Series with no Comparison Group LEVEL OF EVIDENCE: Level IV.

Early and Late Factors Impacting Patient and Graft Outcome in Pediatric Liver Transplantation: Summary of an ESPGHAN Monothematic Conference

As pediatric liver transplantation comes of age, experts gathered to discuss current paradigms and define gaps in knowledge warranting research to further improve patient and graft outcomes. Identified areas ripe for collaborative research include understanding the molecular and cellular mechanisms of tolerance and the role of donor-specific antibodies, considering ways to expand donor pool, minimizing long-term side effects of immunosuppression, and fine-tuning surgical techniques to minimize biliary and vascular complications.

Case report of a modified Meso-Rex bypass as a treatment technique for late-onset portal vein cavernous transformation with portal hypertension after adult deceased-donor liver transplantation

RATIONALE

Portal vein thrombosis is a complication after liver transplantation and cavernous transformation of the portal vein (CTPV) is a result of portal vein thrombosis, with symptoms of portal hypertension revealed by an enhanced CT scan. Meso-Rex bypass is an artificial shunt connecting the left portal vein to the superior mesenteric vein and is mainly used for idiopathic cavernomas. This technique is also used for post-transplant portal vein thrombosis in pediatric patients thereby bypassing obstructed sites of the extrahepatic portal vein. Here we report about an adult patient who was treated by connecting the cystic part of the portal vein to the splenic vein instead of the superior mesenteric vein.

PATIENTS CONCERN

An adult male patient with post-liver transplantation portal vein cavernous transformation suffered from hypersplenism and elevated hepatic enzymes.

DIAGNOSIS

The last follow up revealed irregular and obvious hypersplenism, and splenomegaly had occurred, while an enhanced CT scan revealed serious esophagogastric varices and CTPV in addition to occluded right and common PV trunks.

INTERVENTION

The patient was treated by connecting the cystic part of the portal vein to the splenic vein instead of the superior mesenteric vein.

OUTCOME

After the operation, a satisfactory velocity was confirmed 1 month postoperatively and the shunt still remained patent at the 6-month postoperation follow-up.

LESSONS

A Meso-Rex bypass intervention connecting the left portal vein to the splenic vein instead of the superior mesenteric vein after liver transplantation in an adult patient with right and common portal vein occlusions has been successfully performed as an alternative approach.

Portal vein thrombosis: The role of imaging in the clinical setting

Portal vein thrombosis is an infrequent condition occurring in several different clinical scenarios. In the last years it has been increasingly recognised due to the broad use of radiological methods. In this review we underline the central role of imaging in diagnosing portal vein thrombosis, in clarifying its etiology, choosing the best therapeutic approach and screening possible complications. Special attention is given to the role of imaging to differentiate portal vein thrombosis from neoplastic invasion of the portal vein, and to new diagnostic methods available for clinical practice in this field.

Left branch of portal vein thrombosis in a liver transplant recipient with donation after cardiac death donor: A case report

INTRODUCTION

Portal vein thrombosis (PVT) is one of the most severe complications after liver transplantation, which usually causes graft loss and recipient mortality. The founding of the embolic branch of portal system and its result are not well described in the literature.

CLINICAL FINDINGS AND DIAGNOSES

We report here an unusual case of complete right branch thrombosis of portal vein after orthotopic liver transplantation from a donation after cardiac death donor, without obvious malaise.

THE INTERVENTIONS AND OUTCOMES

The branch thrombosis of portal vein was detected by Doppler ultrasound 11 days after transplantation, followed by angiography for further verification. After treatment with urgent indwelling catheter thrombolysis with urokinase, results improved and the patient showed stable liver function. The patient has been in remission for 22 months with normal graft function.

CONCLUSION

In this case report, we show that frequent ultrasound inspection should be adopted to detect the unobstructed vessel in the early stage of liver transplantation, and local thrombolytic therapy can be used to prevent liver injury and keep the vessel open.

Variant meso-Rex bypass with transposition of abdominal autogenous vein for the management of idiopathic extrahepatic portal vein obstruction: a retrospective observational study

Background

The aim of this study was to evaluate whether variant meso-Rex bypass with transposition of abdominal autogenous vein can be used as an alternative treatment modality for selected patients with symptomatic extrahepatic portal vein obstruction.

Methods

This was a retrospective review of six consecutive patients who received this alternative procedure for the treatment of symptomatic portal hypertension secondary to idiopathic extrahepatic portal vein obstruction. Their clinical characteristics, operative procedures and outcomes were analyzed retrospectively.

Results

The procedure was attempted in six patients, and all had a patent shunt established by intraoperative portography at the end of the procedure; the coronary vein was used in four patients and the inferior mesenteric vein was used in two. During the median period of 23.5 months (range 10–30 months), follow-up was uneventful except one patient; reduced portal hypertension and no new episodes of gastrointestinal bleeding were observed in all patients, with the exception of one patient with shunt stenosis and recurrent varix bleeding who had to undergo endovascular treatment to restore portal vein blood flow. Technical and clinical success was achieved in all patients.

Conclusions

This procedure could be used safely and effectively to treat selected patients with portal hypertension secondary to extrahepatic portal vein obstruction.

Splitting livers: Trans-hilar or trans-umbilical division? Technical aspects and comparative outcomes

Controversy remains about the best line of division for liver splitting, through Segment IV or through the umbilical fissure. Both techniques are currently used, with the choice varying between surgical teams in the absence of an evidence-based choice. We conducted a single-center retrospective analysis of 47 left split liver grafts that were procured with two different division techniques: "classical" (N = 28, Group A) or through the umbilical fissure and plate (N = 19, Group B). The allocation of recipients to each group was at random; a single transplant team performed all transplantations. Demographics, characteristics, technical aspects, and outcomes were similar in both groups. The grafts in Group A, prepared with the classical technique, were procured more often with a single BD orifice compared with the grafts in Group B; however, this was not associated with a higher incidence of biliary problems in this series of transplants (96% actual graft survival rate [median ± s.d.

FOLLOW-UP

26 ± 20 months]). Both techniques provide good quality split grafts and an excellent outcome; surgical expertise with a given technique is more relevant than the technique itself. The classical technique, however, seems to be more flexible in various ways, and surgeons may find it to be preferable.

Advances in the management of childhood portal hypertension

Portal hypertension is one of the most serious complications of childhood liver disease, and variceal bleeding is the most feared complication. Most portal hypertension results from cirrhosis but extra hepatic portal vein obstruction is the single commonest cause. Upper gastrointestinal endoscopy endoscopy remains necessary to diagnose gastro-esophageal varices. Families of children with portal hypertension should be provided with written instructions in case of gastrointestinal bleeding. Children with large varices should be considered for primary prophylaxis on a case-by-case basis. The preferred method is variceal band ligation. Children with acute bleeding should be admitted to hospital and treated with antibiotics and pharmacotherapy before urgent therapeutic endoscopy. All children who have bled should then receive secondary prophylaxis. The preferred method is variceal band ligation and as yet there is little evidence to support the use of β-blockers. Children with extrahepatic portal vein obstruction should be assessed for suitability of mesoportal bypass.

Successful Portal Vein Stent Placement in a Child with Cavernomatous Replacement of the Portal Vein After Partial Liver Transplantation: The Importance of a Recognizable Portal Vein Remnant

Late portal vein thrombosis with cavernomatous replacement has been reported in 4.5% of pediatric patients who have undergone partial liver transplantation. In such cases, minimally invasive radiological treatments have a high failure rate. We report a successful case of percutaneous recanalization of the portal vein remnant, and subsequent stent placement, in a pediatric patient who underwent left lateral split liver transplantation with cavernomatous replacement of the portal vein.

Imaging in clinical decision-making for portal vein thrombosis

Thrombosis of the portal venous system is a frequent and potentially life-threatening condition that can take place in a number of different clinical settings including liver cirrhosis, hepatocellular carcinoma, other solid tumours, abdominal septic foci, acute pancreatitis, haematological malignancies and congenital or acquired prothrombotic disorders. Clinical decision-making in patients with thrombosis of the portal venous system is a particularly complex process owing to the heterogeneity of the population affected by this condition and the lack of high-quality evidence from randomized controlled trials for the use of anticoagulation therapy in these patients. This Review discusses the available data regarding how imaging can provide assistance to physicians involved in this decision-making process in different clinical settings. A flowchart illustrating how to use imaging in this setting, based on current evidence and on the experience of the Vascular Liver Diseases Group of the Hospital Clinic in Barcelona, is also presented.

Management of late-onset portal vein complications in pediatric living-donor liver transplantation

The purpose of this study was to evaluate retrospectively the results of PTA for late-onset PV complications after pediatric LDLT and to assess whether a meso-Rex shunt is a viable option for treating restenosis of the PV after PTA in selected cases. Seventy-five children who underwent adult-to-child LDLT were included in this study, and there were six late-onset PV complications (8.0%). The initial therapeutic approach was PTA, with or without stent: PTA with balloon dilation for three children, PTA with stent placement for one child, and failure to cannulate the occluded PV for two children. A meso-Rex shunt was performed in the two children after failed PTA: One suffered complete obstruction of the main PV, and the other, restenosis with total thrombosis after PTA with stent. The PTA was a technical and clinical success in four with PV stenosis of the six patients (66.7%), and successful application of a meso-Rex shunt in the other two children resulted in restoration of PV flow. In conclusion, PTA is a safe and effective procedure for treating late-onset PV stenosis after pediatric LDLT. However, in growing pediatric recipients with restenosis of the PV after PTA or chronic PV thrombosis, a meso-Rex shunt may be a better choice for late-onset PV complications.

Use of meso-Rex shunt with transposition of the coronary vein for the management of extrahepatic portal vein obstruction

The meso-Rex shunt is used to safely and effectively treat patients with portal hypertension due to extrahepatic portal vein obstruction. In the standard meso-Rex shunt technique, the patient's own internal jugular vein is used as a vascular autograft. Inevitably, such a procedure requires neck exploration and sacrifice of the internal jugular vein. Here, we present a case of a 20-year-old man with idiopathic extrahepatic portal vein obstruction, who was treated with a new technique of transposition of the coronary vein, which is enlarged in most cases of portal hypertension, as an alternative to the standard meso-Rex shunt technique. The transposition of the coronary vein into the Rex recessus is more efficient and less invasive than harvesting an autologous vein graft. Therefore, this technique simplifies the procedure and should be used when possible.

A bidirectional approach for portal vein stent placement in a child with complete portal vein occlusion after living donor liver transplantation

Delayed PV complications are not rare in pediatric liver transplantation. Although PTPV offers a treatment and minimizes surgical revision, in case of complete PV thrombosis (PVT), the failure rate of PTPV is high. Herein, we report a successful technique of PTPV in a case of complete PVT with a stent placement using a bidirectional approach in a child with living donor liver transplantation.

Management and long-term consequences of portal vein thrombosis after liver transplantation in children

Portal vein thrombosis (PVT) occurs in ≤12% of pediatric recipients of liver transplantation (LT). Known complications of PVT include portal hypertension, allograft loss, and mortality. The management of PVT is varied. A single-center, case-control study of pediatric LT recipients with portal vein (PV) changes after LT was performed. Cases were categorized as early PVT (if PVT was detected within 30 days of transplantation) or late PVT (if PVT was detected more than 30 days after transplantation or if early PVT persisted beyond 30 days). Two non-PVT control patients were matched on the basis of the recipient weight, transplant indication, and allograft type to each patient with PVT. Thirty-two of the 415 LT recipients (7.7%) received 37 allografts and developed PVT. In comparison with control patients, a higher proportion of patients with PVT had PVT present before LT (13.3% versus 0%, P = 0.01). Patients with early PVT usually returned to the operating room, and 9 of 15 patients (60%) had PV flow restored. Patients with late PVT had lower white blood cell (4.9 [1000/μL] versus 6.8 [1000/μL], P < 0.01) and platelet counts (140 [1000/μL] versus 259 [1000/μL], P < 0.01), an elevated international normalized ratio (1.2 versus 1.0, P < 0.001), and more gastrointestinal bleeding (25% versus 8.3%, P = 0.03) compared to controls. Patients with PVT were also less frequently at the expected grade level (52% versus 88%, P < 0.001). The patient survival rates were 84%, 78%, and 78% and 91%, 84%, and 79% for cases and controls at 1, 5, and 10 years, respectively. The allograft survival rates were 90%, 80%, and 80% for cases and 94%, 89%, and 87% for controls at 1, 5, and 10 years, respectively. In conclusion, patients with early and late PVT had preserved allograft function, and there was no impact on mortality. Patients diagnosed with early PVT often underwent operative interventions with successful restoration of flow. Patients diagnosed with late PVT experienced variceal bleeding, and some required portosystemic shunting procedures. Academic delays were also more common. In late PVT, the clinical presentation dictates care because the optimal management algorithm has not yet been determined. Multi-institutional studies are needed to confirm these findings and improve patient outcomes.