Mesoportal bypass for extrahepatic portal vein obstruction in children: close to a cure for most!

Wedged hepatic vein portovenography for assessment of Rex vein patency in children with extrahepatic portal venous obstruction

BACKGROUND

Meso-Rex bypass is the surgical intervention of choice for children with extrahepatic portal vein obstruction (EHPVO). Patency of Rex vein, umbilical recessus of the portal vein, is a prerequisite for this surgery. Conventional diagnostic modalities poorly detect patency, while transjugular wedged hepatic vein portography (WHVP) accurately detects patency in 90%.

OBJECTIVES

We aimed to assess Rex vein patency and portal vein branching pattern in children with EHPVO using transjugular WHVP and to identify factors associated with Rex vein patency.

METHODS

Transjugular WHVP was performed in 31 children with EHPVO by selective cannulation of left and right hepatic veins. Rex vein patency, type of intrahepatic portal venous anatomy (Types A-E), and factors associated with patency of Rex vein were studied.

RESULTS

The patency of Rex recess on transjugular WHVP was 29%. Complete obliteration of intrahepatic portal venous radicles was the commonest pattern (Type E, 38.7%) while Type A, the favorable anatomy for meso-Rex bypass, was seen in only 12.9%. Patency of the Rex vein, but not the anatomical pattern, was associated with younger age at evaluation (patent Rex: 6.6 ± 4.9 years vs. nonpatent Rex: 12.7 ± 3.9 years, p = 0.001). Under-5-year children had a 12 times greater chance of having a patent Rex vein (odds ratio: 12.22, 95% confidence interval: 1.65-90.40, p = 0.004). Patency or pattern was unrelated to local factors like umbilical vein catheterization, systemic thrombophilia, or disease severity.

CONCLUSION

Less than one-third of our pediatric EHPVO patients have a patent Rex vein. Younger age at evaluation is significantly associated with Rex vein patency.

Effectiveness of anticoagulant therapy using heparin combined with Plavix after Rex shunt

Purpose

Rex shunt is an optimal surgery for the treatment of extra-hepatic portal venous obstruction (EHPVO) in children. Anticoagulant therapy has been used to keep the patency of the bypass vein in the Rex shunt. This study was to investigate the effectiveness of anticoagulant therapy using heparin combined with Plavix in improving the prognosis and shunt patency of Rex shunt.

Methods

From January 2010 to September 2019, 51 children with EHPVO underwent a portal cavernoma- Rex shunt. Based on whether using the anticoagulant therapy after the Rex shunt, all patients were divided into two groups: the anticoagulant group and the non-anticoagulant group. The diameter and flow velocity of the bypass vein were measured by the post-operative ultrasound, which was used to calculate the flow volume of the bypass vein (FV) and standard portal venous flow (SPVF). The bypass venous flow index (BVFI) was used to evaluate the ability of portal blood into the liver through the bypass vein after the Rex shunt, which was a ratio of FV to SPVF. The incidence of post-operative re-bleeding, the postoperative patency rate of the bypass vein, the remission rate of postoperative hypersplenism, the remission rate of postoperative esophagogastric varices and the BVFI were compared between the two groups.

Results

Of the 51 patients, 12 patients in the anticoagulant group were treated with heparin combined with Plavix after Rex shunt; 39 patients in the non-anticoagulant group were not treated with any anticoagulant therapy. 8 of 51 patients suffered from postoperative re-bleeding, of whom 6 patients with thrombosis of the bypass vein and 2 patients with anastomotic stenosis of the bypass vein. All 8 patients with re-bleeding belonged to the non-anticoagulant group. The remission rate of hypersplenism was no significant difference between the two groups after surgery (91% vs. 58%, P = 0.100). However, 3 patients without hypersplenism before surgery suffered from hypersplenism after surgery, who belonged to the non-anticoagulant group. There was no significant difference in the remission rate of esophagogastric varices (33% vs. 46%, P = 1.000). The BVFI of the anticoagulant group was significantly higher than that of the non-anticoagulant group (5.71 ± 5.89 vs. 1.1 ± 1.52, P = 0.003).

Conclusions

Anticoagulant therapy using heparin combined with Plavix plays an important role in maintaining the patency of the bypass vein, which improved the portal blood flow into the liver through the bypass vein after the Rex shunt.

A History of Umbilical Vein Catheterization Does Not Preclude Children from a Successful Meso-Rex Bypass

INTRODUCTION

 Umbilical vein catheterization (UVC) can cause portal venous thrombosis, leading to the development of extrahepatic portal venous obstruction (EHPVO) and portal hypertension (PHT). The feasibility of the Meso-Rex bypass (MRB) for the treatment of EHPVO in patients with a history of UVC has been questioned. We compared the feasibility of performing an MRB in patients with or without a history of previous UVC.

METHODS

 A retrospective review of patients with EHPVO and known UVC status explored for a possible MRB at our institution was performed (1997-2022). Patients were categorized in two groups: with (UVC(+)) or without (UVC(-)) a history of UVC for comparison. A p-value less than 0.05 was considered significant.

RESULTS

 One hundred and eighty-seven patients were included (n = 57 in UVC(+); n = 130 in UVC(-)). Patients in the UVC group were significantly younger at surgery and the incidence of prematurity was higher. Other risk factors for the development of EHPVO were similar between the groups, but only history of UVC could predict the ability to receive MRB (odds ratio [OR]: 7.4 [3.5-15.4]; p < 0.001). The success rate of MRB was significantly higher in patients with no history of UVC (28/57 [49.1%] in UVC(+) vs. 114/130 [87.7%] in UVC(-); p < 0.001). However, MRB patency at discharge (25/28 [89.3%] in UVC(+) vs. 106/114 [94.7%] in UVC(-); p = 0.3) was equally high in both groups.

CONCLUSION

 Our results indicate that a history of UVC is not a contraindication to MRB. Half of the patients were able to successfully receive an MRB. Patients with symptomatic PHT from EHPVO should not be excluded from consideration for MRB based on UVC history.

Location and extent of cavernous transformation of the portal vein dictates different visceral side revascularization in Meso-Rex bypass

BACKGROUND

As an emerging standard of care for portal vein cavernous transformation (PVCT), Meso-Rex bypass (MRB) has been complicated and variated. The study aim was to propose a new classification of PVCT to guide MRB operations.

METHODS

Demographic data, the extent of extrahepatic PVCT, surgical methods for visceral side revascularization, intraoperative blood loss, operating time, changes in visceral venous pressure before and after MRB, postoperative complications and the condition of bypass vessels after MRB were extracted retrospectively from the medical records of 19 patients.

RESULTS

The median age of the patients (13 males and 6 females) was 32.5 years, while two patients were underage. Causes of PVCT can be summarized as follows: thrombophilia such as dysfunction of antithrombin III or proteins C; secondary to abdominal surgeries; secondary to abdominal infection or traumatic intestinal obstruction, and unknown causes. Intraoperatively, the median operation time was 9.5 h (7-13 h), and the intraoperative blood loss was 300 mL (100-1,600 mL). Ten cases used autologous blood vessels while 10 used allogeneic blood vessels. The vascular anastomosis was divided into the following types according to the site and approach: Type (T) 1-PV pedicel type, T2-confluence type, T3-major visceral vascular type; and T4-collateral visceral vascular type. Furthermore, the visceral venous pressure before and after MRB dropped significantly from 36 cmH2O (28-44) to 24.5 cmH2O (15-31) (P < 0.01). Postoperatively, one patient had delayed wound healing, two developed biochemical pancreatic fistulae, one experienced lymphatic leakage, the former caused by heat damage of the pancreatic tissues, the latter by cutting lymphatic vessels in the mesentery or removing the local lymph nodes during the process of separating the superior mesenteric vein, and one was re-operated on for an intervening intestinal fistulae. Postoperative enhanced CT scans revealed a significant improvement in abdominal varix in the patients with patent bypass, and at the 1-year postoperative follow-up, enhanced CT scans of six patients showed that the long axis of the spleen was reduced by ≥ 2 cm.

CONCLUSIONS

MRB can effectively reduce visceral venous pressure in patients with PVCT. It is feasible to determine the PVCT type according to the extent of involvement and to choose individualized visceral side revascularization performances.

Is re-Rex shunt a better choice for patients with failed Rex shunt?

Purpose

To review our single-center surgical outcomes of redo operations after failed Rex shunt procedures.

Methods

From September 2017 to October 2021, a total of 20 patients (11 males, 9 females; median age: 8.6 years) with Rex shunt occlusions were admitted to our hospital. Two of these patients were previously operated on in our hospital, and the remaining 18 were from other centers. All patients underwent repeat operations after detailed preoperative evaluations.

Results

Preoperative wedged hepatic vein portography (WHVP) was conducted for 18 patients. Thirteen patients exhibited well-developed Rex recessus and intrahepatic portal vein during WHPV examination, consistent with the intraoperative exploration results. Fifteen patients (75%, 15/20) underwent redo-Rex shunt, four underwent Warren shunt and one underwent devascularization surgery. During the redo-Rex shunt operations, the left internal jugular veins (IJV) were used as bypass grafts in 11 patients; the intra-abdominal veins were used in 4 patients. The patients were followed up for 12-59 months (mean, 24.8 months). After redo Rex shunts, the grafts were patent in 14 patients (93.3%, 14/15), but 1 graft had thrombosis (6.7%, 1/15). Three patients suffered from postoperative anastomotic stenosis, and all of the stenosis was relieved with balloon dilatations. After re-Rex shunts, esophageal varices and spleen size were substantially reduced, and the platelet count significantly increased. Postoperative graft thrombosis was found in 1 patient after Warren shunt (1/4, 25%), and there was no graft stenosis. Compared with Warren surgery, patients who underwent re-Rex shunt had a significantly higher rate of platelet increase.

Conclusions

Redo-rex shunts can be finished in most patients with failed Rex shunts. Re-Rex shunt is a preferred surgical choice after a failed Rex shunt when a good bypass graft is available, and the surgical success rate can reach more than 90%. A suitable bypass graft is essential for a successful redo Rex shunt. Preoperative WHVP is recommended for the design of a redo surgical plan preoperatively.

Surgical management of extrahepatic portal vein obstruction in children: advantages of MesoRex shunt compared with distal splenorenal shunt

PURPOSE

To review surgical management of extrahepatic portal vein obstruction (EHPVO) at Red Cross War Memorial Children's Hospital and compare MesoRex shunt (MRS) with distal splenorenal shunt (DSRS).

METHODS

This is a single-centre retrospective review documenting pre- and post-operative data in 21 children. Twenty-two shunts were performed, 15 MRS and 7 DSRS, over an 18-year period. Patients were followed up for a mean of 11 years (range 2-18). Data analysis included demographics, albumin, prothrombin time (PT), partial thromboplastin time (PTT), International normalised ratio (INR), fibrinogen, total bilirubin, liver enzymes and platelets before the operation and 2 years after shunt surgery.

RESULTS

One MRS thrombosed immediately post-surgery and the child was salvaged with DSRS. Variceal bleeding was controlled in both groups. Significant improvements were seen amongst MRS cohort in serum albumin, PT, PTT, and platelets and there was a mild improvement in serum fibrinogen. The DSRS cohort showed only a significant improvement in the platelet count. Neonatal umbilic vein catheterization (UVC) was a major risk for Rex vein obliteration.

CONCLUSION

In EHPVO, MRS is superior to DSRS and improves liver synthetic function. DSRS does control variceal bleeding but should only be considered when MRS is not technically feasible or as a salvage procedure when MRS fails.

Optimal Treatment for Patients With Cavernous Transformation of the Portal Vein

Cavernous transformation of the portal vein (CTPV) is a sequela of extrahepatic and/or intrahepatic portal vein obstruction caused by a combination of local and risk factors. It was ever taken as a relatively rare disease due to its scant literature, which was mainly based on clinical series and case reports. CTPV often manifests as gastroesophageal variceal bleeding, splenomegaly, and portal biliopathy after the long-term insidious presentation. It is unable for CTPV to be recanalized with anticoagulation because it is a complete obstruction of the mesentericoportal axis. Endoscopic therapy is mainly used for temporary hemostasis in acute variceal bleeding. Meso-Rex shunting characterized by portal-flow-preserving shunts has been widely performed in children with CTPV. The multitude of complications associated with CTPV in adults can be effectively addressed by various interventional vascular therapies. With the ubiquity of radiological examinations, optimal treatment for patients with CTPV becomes important. Multivisceral transplantation, such as liver-small intestinal transplantation, may be lifesaving and should be considered for patients with diffuse mesenteric venous thrombosis.

Rex Shunt for Extra-Hepatic Portal Venous Obstruction in Children

Rex shunt, which was first put in use in 1992, has been considered as an ideal surgical method for the treatment of extra-hepatic portal venous obstruction (EHPVO) due to its reconstruction of the hepatopetal portal blood flow. However, despite its long tradition, there are only a few reports about the application and advances in Rex shunt for the treatment of EHPVO in children. In this paper, we summarized the literature related to Rex shunt and discussed the new advances of Rex shunt in the following aspects: surgical method of Rex shunt, the indications of Rex shunt, the strengths of Rex shunt, the effectiveness of Rex shunt, factors affecting the efficacy of Rex shunt, methods that improve the prognosis of Rex shunt, and treatment strategy for recurrence after Rex shunt.

Meso-Rex bypass for the management of extrahepatic portal vein obstruction in adults (with video)

BACKGROUND

Extrahepatic portal vein obstruction (EHPVO) results in severe portal hypertension (PHT) leading to severely compromised quality of life. Often, pharmacological and endoscopic management is unable to solve this problem. Restoring hepatic portal flow using meso-Rex bypass (MRB) may solve it. This procedure, uncommon in adult patients, is considered the treatment of choice for EHPVO in children.

METHODS

From 1997 to 2018, 8 male and 6 female adults, with a median age of 51 years (range 22-66) underwent MRB procedure for EHPVO at the University Hospitals Saint-Luc in Brussels, Belgium. Symptoms of PHT were life altering in all but one patient and consisted of repetitive gastro-intestinal bleedings, sepsis due to portal biliopathy, and/or severe abdominal discomfort. The surgical technique consisted in interposition of a free venous graft or of a prosthetic graft between the superior mesenteric vein and the Rex recess of the left portal vein.

RESULTS

Median operative time was 500 min (range 300-730). Median follow-up duration was 22 months (range 2-169). One patient died due to hemorrhagic shock following percutaneous transluminal intervention for early graft thrombosis. Major morbidity, defined as Clavien-Dindo score ≥ III, was 35.7% (5/14). Shunt patency at last follow-up was 64.3% (9/14): 85.7% (6/7) of pure venous grafts and only 42.9% (3/7) of prosthetic graft. Symptom relief was achieved in 85.7% (12/14) who became asymptomatic after MRB.

CONCLUSIONS

Adult EHPVO represents a difficult clinical condition that leads to severely compromised quality of life and possible life-threatening complications. In such patients, MRB represents the only and last resort to restore physiological portal vein flow. Although successful in a majority of patients, this procedure is associated with major morbidity and mortality and should be done in tertiary centers experienced with vascular liver surgery to get the best results.

Meso-Rex bypass shunt vs. transposition shunt for cavernous transformation of portal vein in children

BACKGROUND

Cavernous transformation of the portal vein (CTPV) causes portal hypertension in children. Among Meso-Rex treatments, it is unclear whether the Meso-Rex bypass shunt (MRB) or the Meso-Rex transposition shunt (MRT) offers lower postoperative morbidity. Our objective was to evaluate postoperative outcomes, comparing MRB and MRT for children with CTPV.

METHODS

A retrospective study was conducted on children undergoing Meso-Rex for CTPV from January 2010 to December 2020. The primary outcome was shunt complications, including shunt stenosis and thrombus. The secondary outcome was re-operation.

RESULTS

Of the 43 patients included, 21 underwent MRT and 22 underwent MRB. MRT was associated with a higher rate of shunt complications when compared to MRB (23.8 vs. 9.1%, p = 0.191). The patients exhibited a higher rate of re-operation under the MRT than under the MRB (19 vs. 4.5%, p = 0.138). The operative time in the MRT group was significantly shorter than in the MRB group. Compared to MRT, the reduction in the length and thickness of the spleen was significantly greater in the MRB group. The increases in platelets were significantly higher in the MRB group than in the MRT group. The postoperative shunt velocity of MRB was notably faster than MRT. There was no significant difference in postoperative portal pressure between the two groups (p > 0.05).

CONCLUSION

Both MRB and MRT result in acceptable postoperative outcomes, but MRT is associated with higher post-shunt complications, which often increase the re-operation rate. This study suggests that MRB may offer advantages for children with CTPV.

Meso-Rex bypass versus portosystemic shunt for the management of extrahepatic portal vein obstruction in children: systematic review and meta-analysis

PURPOSE

Extrahepatic portal vein obstruction (EHPVO) is a major cause of non-cirrhotic portal hypertension in children. Surgical procedures for EHPVO include portosystemic shunts (PSS) and meso-Rex bypass (MRB). We conducted a systematic review and meta-analysis to compare the effectiveness of MRB versus PSS in EHPVO patients.

METHODS

A systematic literature search was performed using four databases. Articles reporting EHPVO and comparing patients who received MRB and PSS were included in the analysis.

RESULTS

We retrieved 851 papers, of which five observational studies met the inclusion criteria. There was no difference in shunt complications, mortality, or gastrointestinal bleeding after surgery between MRB and PSS in the meta-analysis. MRB had increased shunt complications compared with PSS in the non-comparative studies. MRB had a potential advantage over PSS in long-term prognosis in one comparative study. Overall, the quality of the evidence was low.

CONCLUSIONS

Based on available data, our meta-analysis indicates that MRB does not increase shunt complications, mortality, or gastrointestinal bleeding after surgery. The present study did not reveal superiority for either MRB or PSS. The paucity of well conducted trials in this area justifies future multicenter studies and studies that examine long-term outcomes.

Pediatric non-cirrhotic portal hypertension: Endoscopic outcome and perspectives from developing nations

Non-cirrhotic portal hypertension (NCPH) forms an important subset of portal hypertension in children. Variceal bleed and splenomegaly are their predominant presentation. Laboratory features show cytopenias (hypersplenism) and preserved hepatic synthetic functions. Repeated sessions of endoscopic variceal ligation or endoscopic sclerotherapy eradicate esophageal varices in almost all cases. After variceal eradication, there is an increased risk of other complications like secondary gastric varices, cholangiopathy, colopathy, growth failure, especially in extra-hepatic portal vein obstruction (EHPVO). Massive splenomegaly-related pain and early satiety cause poor quality of life (QoL). Meso-Rex bypass is the definitive therapy when the procedure is anatomically feasible in EHPVO. Other portosystemic shunt surgeries with splenectomy are indicated when patients present late and spleen-related issues predominate. Shunt surgeries prevent rebleed, improve growth and QoL. Non-cirrhotic portal fibrosis (NCPF) is a less common cause of portal hypertension in children in developing nations. Presentation in the second decade, massive splenomegaly and patent portal vein are discriminating features of NCPF. Shunt surgery is required in severe cases when endotherapy is insufficient for the varices. Congenital hepatic fibrosis (CHF) presents with firm palpable liver and splenomegaly. Ductal plate malformation forms the histological hallmark of CHF. CHF is commonly associated with Caroli’s disease, renal cysts, and syndromes associated with neurological defects. Isolated CHF has a favourable prognosis requiring endotherapy. Liver transplantation is required when there is decompensation or recurrent cholangitis, especially in Caroli’s syndrome. Combined liver-kidney transplantation is indicated when both liver and renal issues are present.

Optimal Rex shunt procedures as a treatment for pediatric extrahepatic portal hypertension

PURPOSE

To assess the long-term results after Rex bypass (RB) shunt and Rex transposition (RT) shunt and determine the optimal approach.

METHODS

Between 2010 and 2019, traditional RB shunt was performed in 24 patients, and modified RT shunt was performed in 23 children with extrahepatic portal hypertension (pHTN). A retrospective study was conducted based on comparative symptoms, platelet counts, color Doppler ultrasonography and computed tomographic portography of the portal system, and gastroscopic gastroesophageal varices postoperatively. The portal venous pressure was evaluated intraoperatively.

RESULTS

The operation in the RB group was notably more time-consuming than that in the RT group (P < 0.05). Compared to RT shunt, the reduction in gastroesophageal varix grading, the increases in platelets, and the caliber of the bypass were greater in the RB group (P < 0.05). Although not statistically significant, higher morbidity of surgical complications was found after RT shunt (17.4%) compared with RB shunt (8.3%) with patency rates of 82.6 and 91.7%, respectively. Additionally, patients exhibited a lower rate of rebleeding under the RB procedure (12.5%) than under the RT procedure (21.7%).

CONCLUSIONS

The RT procedure is an alternative option for the treatment of pediatric extrahepatic pHTN, and RB shunt is the preferred procedure in our center.

Surgical shunts for extrahepatic portal vein obstruction in pediatric patients: a systematic review

BACKGROUND

Extrahepatic portal vein obstruction (EHPVO) causes portal hypertension in noncirrhotic children. Among surgical treatments, it is unclear whether the meso-Rex shunt (MRS) or portosystemic shunt (PSS) offers lower post-operative morbidity and superior patency over time. Our objective was to evaluate long-term outcomes comparing MRS and PSS for pediatric patients with EHPVO.

METHODS

A systematic review was conducted of articles reporting children undergoing surgical shunts for EHPVO from 1/2000-2/2020. Of 87 articles screened, 22 were eligible for inclusion. The primary outcome was shunt thrombosis and secondary outcomes included non-operative complications, stenosis, and re-operation.

RESULTS

Eighteen of 22 studies were of good quality and four had fair quality. Of 461 patients included, 340 underwent MRS and 121 underwent PSS. MRS were associated with a higher rate of post-operative thrombosis when compared to PSS (14.1% vs 5.8%, p = 0.021). There were 40/340 MRS patients (11.8%) that required at least one re-operation for either shunt thrombosis or stenosis, versus 5/121 PSS patients (4.1%), p = 0.019.

CONCLUSION

Both MRS and PSS result in acceptable long-term patency rates, but the more technically demanding MRS is associated with higher post-shunt thrombosis, often requiring further operative intervention. This study suggests that PSS may offer advantages for pediatric patients with EHPVO.

Applications of hepatic round ligament/falciform ligament flap and graft in abdominal surgery-a review of their utility and efficacy

BACKGROUND AND PURPOSE

Despite their ubiquitous presence, easy availability and diverse possibilities, falciform ligament and hepatic round ligament have been used less frequently than their potential dictates. This article aims to comprehensively review the applications of hepatic round ligament/falciform ligament flap and graft in abdominal surgery and assess their utility and efficacy.

METHODS

Medical literature/indexing databases were searched, using internet search engines, for pertinent articles and analysed.

RESULTS

The studied flap and graft have found utility predominantly in the management of diaphragmatic hernias, gastro-oesophageal reflux disease, peptic perforations, biliary reconstruction, venous reconstruction, post-operative pancreatic fistula, post-pancreatectomy haemorrhage, hepatic cyst cavity obliteration, liver bleed, sternal dehiscence, splenectomy, reinforcement of aortic stump, feeding access, diagnostic/therapeutic access into portal system, composite tissue allo-transplant and ventriculo-peritoneal shunting where they have exhibited the desired efficacy.

CONCLUSIONS

Hepatic round ligament/falciform ligament flap and graft are versatile and have multifarious applications in abdominal surgery with some novel and unique uses in hepatopancreaticobiliary surgery including liver transplantation. Their evident efficacy needs wider adoption to realise their true potential.

Standard or Variant Meso-Rex Shunts for Children with Variceal Bleeding due to Extrahepatic Portal Vein Obstruction: A Report of Two Cases

Extrahepatic portal vein obstruction (EHPVO) is the most common cause of pediatric portal hypertension and can cause life-threatening variceal bleeding. Meso-Rex shunt (MRS) is a surgical procedure that restores physiological portal venous blood flow to the liver by using a graft to connect the superior mesenteric vein and the left portal vein within the Rex recess, and can relieve variceal bleeding and other complications associated with EHPVO. Although the MRS is regarded as an optimal and potentially curative treatment with good long-term patency, graft thrombosis or failure due to unknown causes is not rare, prompting the need for further research on the risk factors of graft failure or poor patency. Herein, we report two cases of EHPVO in patients with recurrent or uncontrolled variceal bleeding, one treated with the classic Rex shunt and the other with the modified Rex shunt, which resulted in a failure and success, respectively.

Long-term Outcomes and Health Perceptions in Pediatric-onset Portal Hypertension Complicated by Varices

OBJECTIVES

Outcomes of pediatric-onset portal hypertension are poorly defined. We aimed to assess population-based long-term outcomes of pediatric-onset portal hypertension complicated by varices.

METHODS

All children with esophageal varices (n = 126) were identified from 14,144 single nationwide referral center endoscopy reports during 1987 to 2013, and followed up through national health care and death registers. A questionnaire was sent to survivors (n = 94) of whom 65 (69%) responded.

RESULTS

Nineteen underlying disorders included biliary atresia (35%), extrahepatic portal vein obstruction (35%), autosomal recessive polycystic kidney disease (7%), and other disorders (23%). During median follow-up of 15.2 (range 0.5-43.1) years patients underwent median 9 (1-74) upper gastrointestinal endoscopies. Esophageal varices were first observed at a median age of 4.0 (0.3-18.2) years, 112 (89%) patients underwent median 6 (1-56) sclerotherapy/banding sessions, and 61 (48%) experienced median 2 (range 1-20) variceal bleeding episodes. Forty-eight surgical shunt procedures were performed to 41 (36%) patients and 38% underwent liver transplantation. Portal hypertensive biliopathy was diagnosed in 4 patients. Hepatopulmonary syndrome necessitated liver transplantation in 2 patients, hepatic encephalopathy in 2, and hepatorenal syndrome in 1. No patient died of variceal bleeding. Patient-reported perception of health on a scale of 1 to 10 was 9 (range 4-10), and 86% reported no current symptoms attributable to esophageal varices.

CONCLUSIONS

Pediatric-onset portal hypertension is a heterogeneous disease with significant long-term morbidity, requiring multimodal approach with considerable resources and continuation of follow-up in adulthood. Although mortality to variceal bleeding was avoided, bleeding episodes recurred also in adulthood, while patient-reported health of long-term survivors was encouraging.

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.

Revision of meso-Rex bypass utilizing a collateral vein in a patient with portal steal phenomenon after liver transplant: A case report

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Re-do of a meso-Rex Bypass is a feasible option with good outcomes.

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A large collateral vein is an alternative for an autologous venous conduit in a MRB.

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Large collaterals ligation during MRB should be performed to avoid portal steal.

Introduction

In children with extrahepatic portal vein obstruction or those who develop portal vein thrombosis after liver transplant, the use of Meso-Rex Bypass (MRB) creates a more physiological state by redirecting mesenteric blood flow back into the intrahepatic portal system via a venous conduit.

Presentation of case

A 3-year-old female with biliary atresia associated with polysplenia syndrome and a surgical history of Kasai portoenterostomy procedure, and an ABO incompatible whole liver transplant. Within a year after transplant she presented with prehepatic portal hypertension, that was treated with MRB using a deceased donor ABO compatible iliac vein as conduit. Six months later, she was taken to the operating room for bypass revision, during the procedure the MRB showed no flow and no thrombus, and a large splenorenal collateral vein that was causing a portal perfusion steal phenomenon was observed. After dissecting the collateral vein, an 8 cm x8 mm segment of this vessel was used as an autologous conduit to re-do the Rex.

Discussion

Failed of MRB can be attributed to portal steal phenomenon, hypercoagulable disorders, bypass contraction or kinking. In this case we believe the culprit to be the former. When there is a history of longstanding portal hypertension, large collaterals develop; thus, intraoperative portal vein flow measurement is critical and ligation of large collaterals during liver transplantation and MRB should be performed to avoid portal steal phenomenon postprocedure.

Conclusion

Using a collateral vein as an alternative autologous venous conduit is a feasible option that can have durable success.

Recanalization of Chronic Extrahepatic Portal Vein Obstruction in Pediatric Patients Using a Minilaparotomy Approach

PURPOSE

Extrahepatic portal vein obstruction (EHPVO) is the most frequent cause of portal hypertension in children. Some patients are not amenable to meso-Rex bypass and alternative surgeries do not restore physiologic flow. We aim to demonstrate the feasibility and safety of minilaparotomy for recanalization of chronic EHPVO.

METHODS

This 2013-2015 single-center, retrospective review included pediatric patients with chronic EHPVO who underwent minilaparotomy, mesenteric vein access, and attempted recanalization of the occluded portal vein. Outcomes included portal patency, resolution of variceal bleeding, size and number of varices, spleen size, and platelet count.

RESULTS

There were 6 EHPVO patients. The median age was 9.9 years and median duration of EHPVO was 7 years (3-16 years). EHPVO etiologies were liver transplantation (50%), idiopathic (33%), and umbilical vein catheterization (17%). Four patients (67%) had successful portal vein recanalization and stenting. At last follow-up [median 3.1 years (2.2-4.3 years)] all successfully recanalized patients had patent portal vein stents and resolution of varices and variceal bleeding. The median reduction in spleen size was 26%, with improvement in platelet counts (50-310/μL). The 2 patients with an idiopathic etiology may have never had a main extrahepatic portal vein based on imaging, and both were unable to be recanalized.

CONCLUSIONS

Recanalization and stenting of a prolonged occlusion of the portal vein via a minilaparotomy approach is feasible, safe, and may provide an alternative to shunt surgery or endoscopic therapy in selected patients.

MR angiography and 2-D phase-contrast imaging for evaluation of meso-rex bypass function

BACKGROUND

The meso-Rex bypass restores blood flow to the liver in patients with extrahepatic portal vein thrombosis. Stenosis occurs in some cases, causing the reappearance of portal hypertension. Complications such as thrombocytopenia present on a spectrum and there are currently no guidelines regarding a threshold for endovascular intervention. While Doppler ultrasound (US) is common for routine evaluation, magnetic resonance (MR) angiography with two-dimensional phase-contrast MRI (2-D PC-MRI) may improve the assessment of meso-Rex bypass function.

OBJECTIVES

To determine the feasibility and utility of MR angiography with 2-D PC-MRI in evaluating children with meso-Rex bypass and to correlate meso-Rex bypass blood flow to markers of portal hypertension.

MATERIALS AND METHODS

MR angiography and 2-D PC-MRI in meso-Rex bypass patients were retrospectively analyzed. Minimum bypass diameter was measured on MR angiography and used to calculate cross-sectional area. Meso-Rex bypass blood flow was measured using 2-D PC-MRI and divided by ascending aortic flow to quantify bypass flow relative to systemic circulation. Platelet and white blood cell counts were recorded. Correlation was performed between minimum bypass area, blood flow and clinical data.

RESULTS

Twenty-five children (median age: 9.5 years) with meso-Rex bypass underwent MR angiography and 2-D PC-MRI. The majority of patients were referred to imaging given clinical concern for complications. Eighteen of the 25 patients demonstrated >50% narrowing of the bypass cross-sectional area. The mean platelet count in 19 patients was 127 K/μL. There was a significant correlation between minimum cross-sectional bypass area and bypass flow (rho=0.469, P=0.018) and between bypass flow and platelet counts (r=0.525, P=0.021).

CONCLUSION

Two-dimensional PC-MRI can quantify meso-Rex bypass blood flow relative to total systemic flow. In a cohort of 25 children, bypass flow correlated to minimum bypass area and platelet count. Two-dimensional PC-MRI may be valuable alongside MR angiography to assess bypass integrity.

Portal-to-right portal vein bypass for extrahepatic portal vein obstruction

OBJECTIVE

Rex shunt (mesenteric-to-left portal vein bypass) is considered a more physiologically rational treatment for EHPVO than other portosystemic systemic shunts in children. However, about 13.6% of children with EHPVO do not have usable left portal veins and up to 28.1%. Rex operations in children are not successful. Hence, a Rex shunt in these children was impossible. This study reports a novel approach by portal-to-right portal vein bypass for treatment of children with failed Rex shunts.

MATERIAL AND METHODS

Eight children (age 6.1years, range 3.5-8.9years) who underwent Rex shunts developed recurrent gastrointestinal bleeding and hypersplenism 13months (11-30months) postoperatively. After ultrasound confirmation of blocked shunt, they underwent exploration. Three patients were found to have right portal vein agenesis. Five patients (62.5%) were found to have the patent right portal vein, with the diameter of 3-6mm. Four patients underwent bypass between the main portal vein in the hepatoduodenal ligament and the right portal vein by interposing an inferior mesenteric vein autograft, whereas the remaining patient underwent a bypass using ileal mesenteric vein autograft.

RESULTS

The operations took 2.3h (1.9-3.5h). The estimated blood loss was 50ml (30-80ml), with no complication. The portal venous pressure dropped from 34.6cmH₂O (28-45 cmH₂O) before the bypass to 19.6cmH₂O (14-24cmH₂O) after the bypass. The 5 patients were followed up for 10.2months (4-17months) and the post-operative ultrasound and CT angiography confirmed the patency of all the grafts and disappearance of the portal venous cavernova in all five patients.

CONCLUSION

The portal-to-right portal vein bypass technique is feasible and safe for treatment of children with EHPVO who have had failed Rex shunts. Our preliminary result indicates that this technique extends the success of Rex shunt from left portal vein to right portal vein and open a new indication of physiological shunt for some of the children who not only have had failed Rex shunts or but also are not suitable for the Rex shunts.

TYPE OF STUDY

Treatment study.

LEVEL OF EVIDENCE

Level IV.

Liver atrophy and regeneration in noncirrhotic portal vein thrombosis: Effect of surgical shunts

The goal of the study is to characterize the relationship between portal vein thrombosis (PVT) and hepatic atrophy in patients without cirrhosis and the effect of various types of surgical shunts on liver regeneration and splenomegaly. Patients without cirrhosis with PVT suffer from presinusoidal portal hypertension, and often hepatic atrophy is a topic that has received little attention. We hypothesized that patients with PVT have decreased liver volumes, and shunts that preserve intrahepatic portal flow enhance liver regeneration. Sixty-four adult and pediatric patients with PVT who underwent surgical shunt placement between 1998 and 2011 were included in a retrospective study. Baseline liver volumes from adult patients were compared with standard liver volume (SLV) as well as a group of healthy controls undergoing evaluation for liver donation. Clinical assessment, liver function tests, and liver and spleen volumes from cross-sectional imaging were compared before and after surgery. A total of 40 patients received portal flow-preserving shunts (32 mesoportal and 8 selective splenorenal), whereas 24 received portal flow-diverting shunts (16 nonselective splenorenal and 8 mesocaval). Baseline adult liver volumes were 26% smaller than SLV (1248 versus 1624 cm³ ; P = 0.02) and 20% smaller than the control volumes (1248 versus 1552 cm³ ; P = 0.02). Baseline adult spleen volumes were larger compared with controls (1258 versus 229 cm³ ; P < 0.001). Preserving shunts were associated with significant increase in liver volumes (886 versus 1131 cm³ ; P = 0.01), whereas diverting shunts were not. Diverting shunts significantly improved splenomegaly. In conclusion, we have demonstrated that patients without cirrhosis with PVT have significant liver atrophy and splenomegaly. Significant liver regeneration was achieved after portal flow-preserving shunts. Liver Transplantation 24 881-887 2018 AASLD.

Postoperative enlargement and prognostic effects of portal venous bypass grafts in children undergoing Rex shunt

OBJECTIVE

Patency of the bypass vein after a Rex shunt is an important indicator of prognosis. However, there is no report about the change of caliber of the bypass vein after a Rex shunt. The aim of this study was to identify postoperative changes of the bypass vein and to assess the relationship with prognosis.

METHODS

Between October 2008 and October 2016 in our center, 114 children were diagnosed with extrahepatic portal venous obstruction. The portal cavernoma-portal bypass with interposition of grafted portal vessels was performed in 31 children, the gastroportal shunt was performed in 54 children, and other Rex shunts were performed in another 29 children. At follow-up, the patency and diameter of the bypass vein were assessed with ultrasound and computed tomography. The intraoperative and postoperative diameters of the bypass vein were compared to identify postoperative changes of the bypass vein. Prognosis was compared between children with and children without an enlarged bypass vein.

RESULTS

The caliber of the bypass vein was enlarged in 50% of children (40/80) at 6 months postoperatively. The postoperative incidences of rebleeding and esophageal varices were significantly lower in children with an enlarged bypass vein than in those without (P < .05). Postoperatively, the reduced splenic size was significantly higher in children with an enlarged bypass vein than in those without (P < .05). The postoperative increase in platelet count in children with an enlarged bypass vein was significantly higher than in those without (P = .006). There was no significant difference in the flow velocity of the bypass vein between children with and children without an enlarged bypass vein (P = .133). The portal pressure was significantly reduced after surgery in children with an enlarged bypass vein than in children without an enlarged bypass vein (P = .017).

CONCLUSIONS

The caliber of the bypass vein increases in 50% of children after a Rex shunt using a grafted portal vessel, which is related to a better prognosis.

Surgical treatment for rebleeding caused by bypass failure after Rex shunt: re-Rex shunt or Warren shunt?

PURPOSE

Although Rex shunt is an effective treatment for extrahepatic portal venous obstruction (EHPVO), 4-20% children develop rebleeding postoperatively. This study was used to evaluate the surgical treatment of rebleeding after Rex shunt in our center.

METHOD

From June 2008 to Jan 2017, 12 of 122 children with EHPVO underwent a second operation due to graft stenosis and occlusion after Rex shunt in our center. The abdominal ultrasound and computed tomography (CT) showed the occlusion of bypass vein in nine children, stenosis of bypass vein in two children, and the patency of bypass vein in one child with dysplasia of intrahepatic portal vein. A re-Rex shunt was performed in eight children, of which one child required conversion to Warren shunt due to postoperative rebleeding. Five children underwent Warren shunt due to a narrowed left portal vein shown by intraoperative portal angiography and surgical exploration. All patients were followed up in this study.

RESULTS

The postoperative incidences of re-bleeding and esophageal varices in children with Warren shunt were significantly lower than those in children undergoing re-Rex shunt (P = 0.027 and 0.015). After a second operation, the rate of bypass vein patency in children with re-Rex shunt was lower than that in children with Warren shunt (50 vs. 100%). The postoperative reduced size of spleen in children undergoing Warren shunt was significantly higher than that of children undergoing re-Rex shunt (P < 0.05).

CONCLUSIONS

Comparing to re-Rex shunt, Warren shunt was a better treatment for rebleeding caused by bypass failure after Rex shunt.

Extrahepatic Portal Venous Obstruction: What Should be the Mainstay of Treatment?

The two cornerstones of management for Extrahepatic portal vein obstruction (EHPVO) are endotherapy and surgery [Porto-systemic shunts (PSS)/Mesorex bypass (MRB)]. Endotherapy is the mainstay of treatment for acute variceal bleed control and has also been used extensively for secondary prophylaxis till variceal eradication is achieved. However, long-term follow-up beyond endoscopic eradication of esophageal varices (EEEV) indicates that there are numerous delayed bleed and non bleed sequelae of EHPVO, which merit surgery as a definitive procedure to decompress the hypertensive portal venous system. While endotherapy obliterates natural porto-systemic collaterals in the gastroesophageal region, persistently raised portal pressures manifest as an increase in secondary isolated gastric varices, ectopic varices, portal hypertensive vasculopathy, issues related to massive splenomegaly, portal biliopathy, growth retardation and hence impaired quality of life (QOL). An ideal management strategy should address both bleed and non-bleed consequences of EHPVO and translate into a near normal QOL. Further, MRB has opened up new dimensions to the management philosophy of EHPVO. This review article critically evaluates the role of surgery and endotherapy based on available literature and authors' own experience.Surgery and endotherapy are complementary. However, with increasing duration of follow-up post EEEV, it is evident that there is resurgence in the role of surgery (PSS/MRB) as a single one time definitive procedure for alleviating all bleed and delayed non bleed sequelae of EHPVO.Surgery for EHPVO (PSS/MRB) should not be allowed to become a dying art and future generations of surgeons should continue to receive training in this specialized area of surgery.

Pediatric Vascular Surgery Review with a 30-Year-Experience in a Tertiary Referral Center

Pediatric vascular disease is rare, and remains a big challenge to vascular surgeons. In contrast to adults, surgery for pediatric vascular disease is complicated by issues related to small size, future growth, and availability of suitable vascular conduit. During the last 30 years, 131 major vascular operations were performed in a tertiary referral center, Seoul National University Hospital, including aortoiliac aneurysm, acute or chronic arterial occlusion, renovascular hypertension, portal venous hypertension, trauma, tumor invasion to major abdominal vessels, and others. Herein we review on the important pediatric vascular diseases and share our clinical experiences on these rare diseases.

Combined Rex-bypass shunt with pericardial devascularization alleviated prehepatic portal hypertension caused by cavernomatous transformation of portal vein

OBJECTIVE

To evaluate the effects of combined Rex-bypass shunt and pericardial devascularization on prehepatic portal hypertension secondary to cavernomatous transformation of portal vein (CTPV).

METHODS

Forty-two patients aged from 3 years to 49 years (divided into 3 groups), 26 cases male and 16 female, with prehepatic vascular hepertention were treated with Rex-bypass shunt combined with pericardial devascularization. In each patient, preoperative assessment included ultrasound and computed tomographic angiography of the portal vein and blood analysis. The procedure was Rex-bypass shunt (with or without graft), and patients with moderate or severe gastroesophageal varices required additional paraesophagogastric devascularization. Splenectomy or subtotal splenectomy was performed if combined hypersplenism co-existed. All data were analyzed retrospectively.

RESULTS

No intraoperative death occurred, blood routine analysis improved (P < 0.05), the blood flow velocity (P < 0.05) and diameter (P < 0.05) of the left portal vein (LPV) significantly increased, the esophageal and gastric varices significantly relieved in 34 patients (P < 0.05), and better effects of earlier operations were demonstrated than the delayed ones (P < 0.05). During the period of follow-up from 6 to 64 months, the overall patency rate was 85.7% and the younger the age the better of the effect.

CONCLUSION

Rex-bypass shunt combined with pericardial devascularization is a safe and effective procedure for prehepatic portal hypertension caused by CTPV.

Primary prophylaxis of variceal bleeding in children and the role of MesoRex Bypass: Summary of the Baveno VI Pediatric Satellite Symposium

Approaches to the management of portal hypertension and variceal hemorrhage in pediatrics remain controversial, in large part because they are not well informed by rigorous clinical studies. Fundamental biological and clinical differences preclude automatic application of approaches used for adults to children. On April 11-12, 2015, experts in the field convened at the first Baveno Pediatric Satellite Meeting to discuss and explore current available evidence regarding indications for MesoRex bypass (MRB) in extrahepatic portal vein obstruction and the role of primary prophylaxis of variceal hemorrhage in children. Consensus was reached regarding MRB. The vast majority of children with extrahepatic portal vein obstruction will experience complications that can be prevented by successful MRB surgery. Therefore, children with extrahepatic portal vein obstruction should be offered MRB for primary and secondary prophylaxis of variceal bleeding and other complications, if appropriate surgical expertise is available, if preoperative and intraoperative evaluation demonstrates favorable anatomy, and if appropriate multidisciplinary care is available for postoperative evaluation and management of shunt thrombosis or stenosis. In contrast, consensus was not achieved regarding primary prophylaxis of varices. Although variceal hemorrhage is a concerning complication of portal hypertension in children, the first bleed appears to be only rarely fatal and the associated morbidity has not been well characterized.

CONCLUSION

There are few pediatric data to indicate the efficacy and safety of pharmacologic or endoscopic therapies as primary prophylaxis or that prevention of a sentinel variceal bleed will ultimately improve survival; therefore, no recommendation for primary prophylaxis with endoscopic variceal ligation, sclerotherapy, or nonspecific beta-blockade in children was proposed.

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.

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.

Pancreatitis and portal vein thrombosis in children: the chicken or the egg causality dilemma

BACKGROUND

The association of pancreatitis and portal vein thrombosis (PVT) is extremely rare in children. We report on 3 cases which suggest that there may be a causal relation between the two.

METHODS

Clinical characteristics and evolution of 3 children with this particular condition were analyzed retrospectively. In this group of patients, the strategy consisted in opting for early surgical decompression of the portal hypertension, which was followed by a favorable outcome, not only in terms of complications related to the portal hypertension but also of a contemporaneous spontaneous regression of the concurrent pancreatic disease, in absence of any other specific management of the latter problem.

RESULTS AND CONCLUSIONS

Combined PVT and pancreatitis is exceptional in children. Although this series is small, it provides insight and some evidence that the pancreatic disease might be secondary to the cavernomatous transformation of the regional venous system. More interestingly, it suggests that the appropriate management strategy should be to rapidly relieve portal hypertension after resolution of the acute phase of pancreatitis.

Meso-Rex bypass to manage prehepatic portal hypertension after the failure of an intrahepatic portosystemic stent shunting

A cavernomatous transformation of the extrahepatic portion of the portal vein is a common cause of chronic portal hypertension in children. A few attempts at radiological interventions have been reported, but have rarely been successful. In this report, a surgical Meso-Rex bypass was performed to treat complicated prehepatic portal hypertension, after the insertion of an intrahepatic stent for portosystemic shunting had failed. The review of this case nicely illustrates how differently effective are these two shunting procedures-in terms of restoring hepatopetal flow, managing portal hypertension, and establishing-or not-portosystemic connections.

Partial splenectomy and use of splenic vein as an autograft for meso-Rex bypass: a clinical observational study

Background

Meso-Rex bypass (MRB) surgery is being increasingly used to treat chronic prehepatic portal hypertension secondary to extrahepatic portal vein thrombosis (EPVT) and cavernous transformation (EPVCT) in children. Rather than using the internal jugular vein (IJV, the traditional venous graft), we used an autogenous splenic vein segment graft for MRB.

Material/Methods

We examined 25 children with extrahepatic portal hypertension and a history of recurrent upper gastrointestinal (GI) variceal bleeding despite previous endoscopic sclerotherapy. All patients had melena, splenomegaly, hypersplenism, or some combination thereof. Left portal vein (LPV) patency was verified in 22 patients using intraoperative direct portography through the umbilical vein. Partial splenectomy was performed to enable the harvest of the splenic vein trunk, which was anastomosed between the superior mesenteric vein (SMV) and the left portal vein (LPV). All patients were followed for 12–48 months (mean=25.6 months) and no patients were lost to follow-up.

Results

Preoperative Doppler ultrasound (US) imaging indicated that 18/25 patients had adequate intrahepatic portal veins for shunting, with no blood flow in the LPVs of 7 patients. LPV patency in 22/25 patients was verified using intraoperative direct portography, with successful MRB. Shunting was converted into a portosystemic shunt in the remaining 3/25 patients with thrombosed LPVs. A Doppler US evaluation of the vein conduit revealed excellent postoperative flow. The patients’ mean hemoglobin, platelet, and white blood cell counts increased significantly, and in all cases the endoscopic status obviously improved after shunting. Occlusion or narrowing occurred in 2/22 patients after discharge. At 12 months (for 1 patient) and 24 months (for 1 patient), the shunt was converted into a portosystemic shunt. The cumulative graft patency rate was 91% (20/22).

Conclusions

Partial splenectomy and splenic vein autografting in MRB surgery can successfully resolve prehepatic portal hypertension and hypersplenism in children.

Intrahepatic portal venous systems in children with noncirrhotic prehepatic portal hypertension: anatomy and clinical relevance

BACKGROUND

Children with extrahepatic portal hypertension typically present with cavernomatous transformation of the portal vein and a poorly defined intrahepatic portal vein system on conventional imaging. With the Meso-Rex Bypass becoming the gold-standard intervention for a cure, a precise assessment of the intrahepatic portal vein system provides helpful data for deciding whether a Meso-Rex Bypass is feasible or not.

METHODS

All children with extrahepatic portal hypertension were prospectively assessed by wedged hepatic venous portography. Venous anatomy was categorized into five subtypes (A to E), depending on the presence of thrombosis in the Rex recessus, or not, and its extension within the intrahepatic portal venous system.

RESULTS

Eighty-nine children entered the study. Previous umbilical vein catheterization is usually associated with Rex thrombosis, while the Rex recessus and the intrahepatic portal venous system are patent in idiopathic cases, thus allowing for the performance of a Meso-Rex Bypass with a good outcome.

CONCLUSIONS

Wedged hepatic venous portography is a very effective tool for detailed preoperative assessment and identification of children being considered for Meso-Rex Bypass surgery. An anatomic-radiological classification is useful in selecting patients for Meso-Rex Bypass with anticipation of a high rate of success.

[Cavernous transformation of the portal vein in children: about 11 cases]

Le cavernome portal est la conséquence d'une occlusion chronique, du système porte extra-hépatique formé d'un réseau de veines dont le calibre est augmenté et au sein desquelles chemine un sang portal hépatopéte. Chez l'enfant, est une cause majeure d'hypertension portale dite «pré ou infra-hépatique» ou encore «extra-hépatique». Onze cas de cavernome porte parmi 78 cas d'hypertension portale ont été colligés au service sur une période allant du Janvier 2003 au Septembre 2012. L’âge de nos patients variait entre 2 et 15 ans et le sexe ratio est de 1,75. Tous nos patients étaient admis au stade d'hypertension portale avec la splénomégalie SMG (100% des cas); hémorragies digestives (63%); ascite (36%); la circulation veineuse collatérale CVC et l'hépatomégalie HMG (27%). L'exploration endoscopique a objectivé la présence de varices ‘sophagiennes dans tous les cas avec une gastropathie hypertensive dans 27% et des varices ectopiques chez 36%. Les perturbations biologiques étaient dominées par la pancytopénie. Le bilan de thrombophilie était demandé pour tous les malades mais réalisé mais n'est réalisé que chez trois revenus normaux chez deux et a objectivé une baisse de protéine S chez le troisième. L’échographie abdominale était le moyen de diagnostic positif et l’écho-doppler a confirmé l'HTP chez tous nos patients. Aucun de nos malades n'a pu être opéré pour le moment. La ligature a été réalisée chez 54,5%. Dix patients ont nécessité une transfusion sanguine. L’évolution globale de nos patients est favorable. La durée moyenne d’évolution du cavernome porte chez nos patients est de quatre ans.

Meso-Rex bypass for extrahepatic portal vein obstruction in children

Background

Meso-Rex bypass (MRB) and portosystemic surgical shunt (PSS) are both used to treat extrahepatic portal vein obstruction (EHPVO) in children. The aim of this study was to analyse the outcome of MRB and PSS to select patients who could benefit from a prophylactic MRB.

Methods

This single-centre retrospective study of children who underwent either MRB or PSS for EHPVO was conducted between 1996 and 2010. Details of patient demographics and preoperative evaluation were collected. Success rates, defined as shunt patency after a minimum of 6 months and clearance of varices or symptoms, were compared. Determinants of outcomes were explored.

Results

Sixty-nine patients underwent a MRB or PSS. Median (interquartile range, i.q.r.) age at surgery was 6·6 (4·0–10·6) years. Twenty-four patients (35 per cent) had had a neonatal umbilical catheter (NUC) placed previously and 47 (68 per cent) had experienced an upper gastrointestinal bleed. Imaging assessment of the intrahepatic left portal vein was considered favourable in 40 patients. Of 43 MRBs attempted, 11 failed during surgery and four patients had persistent thrombosis after a median of 55 (i.q.r. 18–107) months. The success rate of MRB was 60 per cent (26 of 43) compared with 100 per cent (26 of 26) for PSS (P &lt; 0·001). It was lower among patients in whom a NUC had been used (2 of 10 versus 24 of 33; P = 0·004), for procedures undertaken early in the series (6 of 16 versus 20 of 27; P = 0·020) and when the imaging pattern was unfavourable (0 of 5 versus 26 of 38; P = 0·006). On multivariable analysis, only a previous history of NUC predicted failure (P = 0·016).

Conclusion

Prophylactic MRB seems a good treatment option for EHPVO in children, but should be done only by an experienced team in patients with favourable imaging and without a previous history of NUC.

Presented in part to the 43rd Annual Meeting of the American Pediatric Surgical Association, San Antonio, Texas, USA, May 2012

Living donor liver transplantation with alternative porto-left gastric vein anastomosis in patients with post-Kasai extrahepatic portal vein obstruction

EPVO is a common cause of prehepatic portal hypertension in pediatric patients and sometimes results in cavernous transformation of the PV. We herein present the cases of two patients who underwent LDLT for EPVO with post-Kasai biliary atresia. PV reconstruction was performed with a porto-left gastric vein anastomosis. The patient who underwent PV reconstruction using an interposition vein graft is doing well without surgical complications, whereas PV anastomotic stenosis was detected three months after LDLT in the patient who did not receive an interposition vein graft. The availability of vein grafts is limited in the LDLT setting. In such cases, performing PV reconstruction with varicose veins using interposition vein grafts is a feasible and valuable alternative option for obtaining a sufficient portal blood flow. Our experiences suggest that using interposition vein grafts may be appropriate for preventing the anastomotic stenosis caused by the fragility of varicose veins.

Surgical and endovascular treatment of severe complications secondary to noncirrhotic portal hypertension: experience of 56 cases

BACKGROUND

Major complications of noncirrhotic portal hypertension (NCPH) include bleeding esophagogastric varices, hypersplenism, ascites, and bowel ischemia under acute circumstances. The aim of this article is to determine the outcomes of surgical and endovascular treatments for severe complications from NCPH.

METHODS

From January 2000 to June 2011, 56 patients with symptomatic NCPH underwent open surgery or endovascular thrombolysis. The medical records were retrospectively reviewed. Of the 56 patients, there were 39 males and 17 females. The mean age was 21 years, ranging from 2 to 54 years. Forty-one of them were diagnosed to have prehepatic portal vein obstruction (PHPVO), 9 had Budd-Chiari syndrome (BCS), and 6 had noncirrhotic portal fibrosis (NCPF). All patients were symptomatic from 5 days to 14 years (mean 25 months). Portosystemic shunt (PSS) was primarily performed in 49 patients. Shunts were as follows: 35 mesocaval; 7 splenorenal; 4 portocaval; 2 paraumbilical-jugular; and 1 portal to right atrial. Esophagogastric devascularization was performed in 3 patients, but was converted to mesocaval shunt later in 2. The remaining 4 patients with acute superior mesenteric vein (SMV) and portal vein thrombosis were treated with endovascular catheter-directed thrombolysis. Warfarin was prescribed to all the patients for at least 6 months. Mean follow-up was 57 months, ranging from 2 to 125 months. The outcomes, focusing on 30-day mortality, recurrent bleeding, and hypersplenism, were recorded.

RESULTS

In the 49 patients undergoing primary PSS, the shunts remained patent and there was no recurrent variceal bleeding during the follow-up. All 3 patients with esophagogastric devascularization had recurrent variceal bleeding at 8, 13, and 24 months postoperatively. Two of them were converted to mesocaval shunt, and 1 died before redo operation. Thrombolysis in all 4 patients with acute SMV and portal thrombosis was technically successful. Three of the 4 survived without complications and 1 died from small bowel infarction due to recurrent thrombosis 40 days later. In the 47 patients with hypersplenism, mean platelet counts increased from 43×10(9)/L to 239×10(9)/L 2 weeks after surgery. Ascites in 30 of the 31 patients disappeared within 2 months after PSS. There was no postoperative encephalopathy, and perioperative 30-day mortality was 0%.

CONCLUSIONS

PSS can be employed to treat bleeding esophagogastric varices and severe hypersplenism secondary to NCPH. Post-PSS encephalopathy is less of a concern in NCPH patients with normal liver function. Endovascular catheter-directed thrombolysis via superior mesenteric artery is a useful alternative treatment for acute portal and/or mesenteric venous thrombosis.

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

Direct portal revascularization can be achieved by interposing a vascular graft between the SMV and the Rex recessus (left portal vein system): the MRB. To review indications and results of the procedure in the setting of pediatric liver transplantation, reports were selected from the English literature. Previously reported series were updated to analyze long-term outcome. A new series was added and analyzed as a complementary set of cases. A total of 51 cases were analyzed. With a 96% overall patient survival rate and a 100% long-term patency rate when the IJV is used for the bypass, MRB achieves a very successful physiologic cure of chronic portal hypertension and restores the portal flow into and through the liver graft. It also has been used successfully for primary revascularization of liver grafts, as well as for managing early acute portal vein thrombosis episodes. The use of this procedure in conjunction with other strategies and techniques might be of interest for transplant surgeons, particularly those caring for children.

Management of bleeding in extrahepatic portal venous obstruction

Extrahepatic portal venous obstruction, although rare in the western world, is a common cause of major and life threatening upper gastrointestinal bleeding among the poor in developing countries. Patients have large spleens and stunted growth. The diagnosis is easily confirmed by Doppler ultrasonography. Endoscopy sclerotherapy is the best option for the control of acute variceal bleeding. For secondary prophylaxis of bleeding, the choice lies between repeated sclerotherapy and a portosystemic shunt. We believe that due consideration should be given to performing a splenectomy and a lienorenal shunt. Performed by experienced surgeons, it carries a low operative mortality of 1%, a rebleeding rate of about 10%, removes the large spleen, reverses hypersplenism, and is not followed by portosystemic encephalopathy. Most importantly, it is a onetime procedure particularly suited to those who have little access to blood transfusion and sophisticated medical facilities.

Advantages of the meso-Rex bypass compared with portosystemic shunts in the management of extrahepatic portal vein obstruction in children

BACKGROUND

Consequences of extrahepatic portal vein obstruction (EHPVO) include variceal bleeding and hypersplenism due to portal hypertension, as well as metabolic abnormalities secondary to impaired portal venous circulation. The purpose of this study was to compare the effectiveness of meso-Rex bypass and portosystemic shunt (PSS) for reversing these symptoms in children with EHPVO.

STUDY DESIGN

All children with idiopathic EHPVO evaluated for potential meso-Rex bypass at a single institution between 1997 and 2010 were reviewed. Portosystemic shunt was performed in patients with refractory portal hypertension when meso-Rex bypass was not technically feasible. Outcomes of meso-Rex bypass and PSS were compared, including resolution of portal hypertensive bleeding and hypersplenism, as well as changes in liver synthetic function, ammonia levels, and somatic growth.

RESULTS

Sixty-five children with EHPVO underwent successful meso-Rex bypass, while 16 required PSS. Nearly all patients experienced complete relief of variceal bleeding after meso-Rex (96%) bypass and PSS (100%). The improvements in platelet count (+82.1 ± 60.0 vs +32.4 ± 56.3 thousand/μL; p=0.004), internal normalized ratio (-0.22 ± 0.27 vs 0.01 ± 0.14; p=0.022), and serum ammonia level (-26.8 ± 36.8 vs +19.4 ± 33.1 μM/L; p=0.002) were greater after meso-Rex bypass than PSS. Among patients with below average (standard deviation z-score<0) preoperative weight for age, the improvement in weight-for-age z-score was greater after meso-Rex bypass (+0.84 ± 0.98) than PSS (+0.17 ± 0.79, p=0.044). Median duration of follow-up was 4.45 years after meso-Rex bypass and 1.8 years after PSS.

CONCLUSIONS

Both meso-Rex bypass and PSS effectively relieve symptoms of portal hypertensive bleeding in children with EHPVO, although the meso-Rex better relieves hypersplenism. By restoring normal portal venous circulation, the meso-Rex bypass has additional metabolic benefits.