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

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.

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.

REX SHUNT IN CHILDREN: COULD DYSFUNCTION BE PROGNOSED? A RETROSPECTIVE ANALYSIS

OBJECTIVE

The aim: To analyze retrospectively our experience of Rex shunt in children with symptomatic portal hypertension, its effect on hypersplenism regression and varices eradication, assess shunt survival and investigate risk factors, that could lead to shunt dysfunction and thrombosis.

PATIENTS AND METHODS

Materials and methods: 24 children (16 males, 8 females) ,with portal hypertension included into the study. All surgeries were performed within single center in a period from January 2010 to March 2022. Follow up period was 6.75±1.19 years.

RESULTS

Results: Age at diagnosis was 5.39±0.64 years. 5 (20.8%) had umbilical catheter in anamnesis. 16 (66.7%) manifested bleeding episodes as the first sign of portal hypertension. 9 (37.5%) of children manifested severe hypersplenism. Age at Rex shunting was 7.5±0.7 years. In 7 (31.8%) cases Rex shunt thrombosis occurred. 1 successful thrombectomy and 6 splenorenal shunting were performed. Kaplan-Meyer analysis showed Rex shunt survival 0.670 (95%CI 0.420-0.831). Logistic regression model indicated thrombocytes count (p=0.0423) and cytopenia (p=0.0272) as factors that could influence shunt thrombosis. Follow-up group included 18 patients. Spleen volume regression became significant by 1 p/o year p<0,05, thrombocytes significant increasement reached in 1 p/o months (p<0.01), varices involution was achieved by 1 p/o year (p<0,001).

CONCLUSION

Conclusions: Rex shunt effectiveness in study group was 70.9%., shunt survival assessed 0.670 (95%CI 0.420-0.831). Rex shunt was effective in bleeding prophylaxis in all patients of follow up group. Preoperative thrombocytes count (p=0.0423) and cytopenia (p=0.0272) were detected as factors that could influence shunt thrombosis, that is to be considered in RS preoperative period and require following studies.

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.

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.

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.

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.