Long-Term Outcome of Portal Vein Stent Placement in Pediatric Liver Transplant Recipients: A Comparison with Balloon Angioplasty

Interventional Management of Portal Vein Stenosis after Liver Transplant: Single Center Experience

OBJECTIVES

Portal vein stenosis is a relatively rare complication after liver transplant but has severe consequences. We evaluated the efficacy and longterm results of the endovascular treatment methods for portal vein stenosis.

MATERIALS AND METHODS

From October 2011 to October 2022, we treated 22 patients (5 female, 17 male) with portal vein stenosis using endovascular methods. Doppler ultrasonography was used for initial diagnosis, with consideration of flow rate increase over stenosis, absence of flow, or reduced anastomotic segment size (>50%). Angiography served as the gold standard, with a pressure gradient above 5 mm Hg indicating the need for treatment. Technical success criteria were defined as <50% stenosis remaining and/or a pressure gradient <5mm Hg. The transhepatic approach was used for all patients. Balloon angioplasty was initially performed, and stents were reserved for patients in the early postoperative period or those unresponsive to balloon angioplasty.

RESULTS

The technical success rate was 100%. Mean age was 27.1 years (SD 22.4; range, 4 months to 63 years). Mean time from transplant to intervention was 317 days (range, 0-3135 days). Angioplasty was successful for 7 patients (13.8%). Of 15 patients who underwent stent placement, 9 (40.9%) were in the early postoperative period; in the other 6 patients (27%), results of angioplasty were not satisfactory, and stents were placed. Within 3 months of transplant, 3 patients died because of other complications. Among patients with stents, 2 required reintervention, resulting in reestablishment of good portal venous flow. During the mean follow-up of 24 months (range, 15 days to 9 years), 19 patients (86%) had portal flows within reference limits.

CONCLUSIONS

The endovascular approach is a safe and effective treatment option for management of portal vein stenosis in both adult and pediatric liver transplant recipients in the early or late period.

Balloon angioplasty versus stent placement for the treatment of portal vein stenosis in children: a single center experience

PURPOSE

To evaluate the safety and efficacy of percutaneous interventional treatment of portal vein stenosis in children.

MATERIAL AND METHODS

A retrospective analysis of all interventional treatments for portal vein stenosis in pediatric patients at a single institution from 2010 to 2021 was conducted. Platelet count, spleen size and portal vein flow velocity were assessed during the follow-up period. Primary and primary assisted patency time were determined.

RESULTS

A total of ten children (median age 28.5 months, interquartile range (IQR): 2.75-52.5 months) with portal vein stenosis after Mesorex-Shunt (n = 4), liver transplantation (n = 3) and other etiologies (n = 3) underwent 15 interventional procedures. There were five reinterventions and one discontinued intervention. The technical success rate was 93.3% (14/15) and clinical success of treated patients was 100% (14/14). Median follow-up was 18 months (IQR: 13.5-81 months). The median primary patency time for stent placement was 70 months (IQR: 13.5-127.25 months). For balloon angioplasty, the median primary patency time was 9 months (IQR 7.25-11.5 months), while the median assisted primary patency time was 14 months (IQR: 12 to 15 months). Platelet count, spleen size and portal vein flow velocity reliably corresponded to recurrence of portal vein stenosis in asymptomatic patients during follow-up.

CONCLUSION

Interventional treatment is a safe and efficient method to treat portal vein stenosis with long patency times, regardless of etiology. Primary stent placement shows a higher primary patency time than balloon angioplasty. Implementation of stent placement as the primary interventional method may improve patency times and reduce the need for repeat reinterventions in pediatric patients.

Percutaneous radiological interventions of the portal vein: a comprehensive review

The portal vein is the largest vessel supplying the liver. A number of radiological interventions are performed through the portal vein, namely for primary pathologies of the portal vein, for inducing liver hypertrophy or to treat the sequelae of portal hypertension among others. The routes used include direct transhepatic, transjugular, and, uncommonly, trans-splenic and through subcutaneous varices. Portal vein embolization and transjugular intrahepatic portosystemic shunt are among the most common portal vein interventions that are performed to induce hypertrophy of the future liver remnant and to treat complications of portal hypertension, respectively. Other interventions include transhepatic obliteration of varices and shunts, portal vein thrombolysis, portal vein recanalization, pancreatic islet cell transplantation, and embolization of portal vein injuries. We present a detailed illustrative review of the various radiological portal vein interventions.

Long-term efficacy and risk factors for stent occlusion in portal vein stent placement: a multi-institutional retrospective study

Background

Surgical treatment for PV (portal vein) stenosis/occlusion can pose a fatal risk of massive bleeding from severe adhesions and collateral vessel formation. PV stents placement is a minimally invasive and effective procedure for PV stenosis/occlusion, but PV stents sometimes occlude. The relationship between post-stent PV hemodynamics and stent occlusion has not been thoroughly investigated. Certain precautions during PV stent placement may reduce the risk of stent occlusion. This study aimed to evaluate long-term outcomes of PV stent patency and investigate factors including PV hemodynamics associated with stent occlusion.

Materials and methods

Thirty-four consecutive patients with PV stenosis/occlusion who underwent PV stent placement in four institutions between December 2006 and February 2021 were retrospectively examined. The primary study endpoints were technical success, clinical success, and cumulative stent patency rate. The secondary endpoints were risk factors of stent occlusion. A univariable Cox proportional hazards model with sixteen variables was used to determine predictors of stent occlusion. Factors with p-value ≤ 0.1 in univariable analysis were included in the multivariable analysis. Alpha was set at 0.05.

Results

Technical and clinical success rates were 88.2% and 79.4%, respectively. Six patients (17.7%) experienced stent occlusion. The cumulative stent patency rate at six months, one year, and three years was 79.1%, 79.1%, and 65.9%, respectively. In the univariate analysis, the variables with p-value ≤ 0.1 were lesion length > 4 cm, hepatofugal collateral vein visualization after stent placement, and residual stenosis > 30% after stent placement. In the multivariate analysis, residual stenosis > 30% after stent placement was significantly associated with stent occlusion (hazard ratio, 10.80; 95% confidence interval, 1.08–108.44; p = 0.04).

Conclusion

PV stent placement was technically feasible and effective in improving portal hypertension. However, stent occlusion was not uncommon. Residual stenosis > 30% after stent placement was significantly associated with stent occlusion. We should pay attention to correctly assess the range of stenosis and release the stenosis as much as possible.

Long-term outcome of primary percutaneous stent angioplasty for pediatric posttransplantation portal vein stenosis

This study aims to evaluate the long-term efficacy and reintervention rate after primary percutaneous portal vein stent angioplasty for portal vein stenosis (PVS) in pediatric liver transplantation (LT) recipients. From 2004 to 2020, a total of 470 pediatric LTs were performed in our center. All cases were screened for interventional PVS treatment and analyzed retrospectively. We identified 44 patients with 46 percutaneous angioplasties for posttransplantation PVS. The median interval from LT to percutaneous catheter intervention was 5 months (16 days-104 months) with a median follow-up (f/u) period after catheter intervention of 5.7 years (2-156 months). In 40 patients, an endovascular stent was placed as primary (n = 38) or secondary (n = 2) intervention. The median age at stent placement was 23 (6-179) months with a median weight of 10 kg (6-46 kg). Technical success and relief of PVS were achieved in all patients irrespective of age or weight. Adverse events occurred peri-interventionally in two patients and were resolved with standard care. All primary portal vein (PV) stents remained patent until the end of f/u. Reinterventions have been successfully performed in 10 patients for suspected or proven restenosis, resulting in a primary patency rate of 75% and an assisted patency rate of 25%. The median time to reintervention was 6.2 years (range 1-10 years). The need for reintervention was independent of age or weight at both transplantation and initial angioplasty as well as of additional risk factors due to portal hypertension. Percutaneous transhepatic PV stent angioplasty in children is safe and effective in all age groups, with excellent long-term patency. Primary stent angioplasty should be considered as first-line treatment for PVS after pediatric LT.

Treatment With Balloon Angioplasty of Chronic Portal Vein Thrombosis

The therapeutic options in portal vein thrombosis cases of young age and low weight, as in this case, are limited. Interventional radiologists also have minimal experience in pediatric patients. There are no reported cases anywhere worldwide, especially in this age group. However, we think that balloon angioplasty can be safely applied in cases in which esophageal variceal bleeding cannot be controlled using traditional treatment.

Percutaneous transhepatic interventional therapy of portal vein stenosis in paediatric liver transplantation: A systematic review of efficacy and safety

PURPOSE OF THE SYSTEMATIC REVIEW

To determine the efficacy and safety of percutaneous trans-hepatic balloon and/or stent angioplasty (PTA) in the management of portal vein (PV) stenosis following paediatric liver transplantation.

METHODS

Articles were included from a systematic search of Medline, Embase, Cochrane CENTRAL, ClinicalTrials.gov and International Clinical Trials Registry from inception to the 29th of August 2020.

RESULTS

There were 213 paediatric liver recipients who underwent PTA for PV stenosis in 19 included studies published between 1991 and 2019. Balloon angioplasty was the initial treatment in the majority (n = 153). Primary stent placement (n = 34) was performed for elastic recoil, intimal tears and PV kinks and rescue stent placement (n = 14) for recurrent PV stenosis following primary balloon angioplasty. The technical success was 97.6%-100% overall, 97.6%-100% for balloon-angioplasty-only and 100% for primary stenting. The clinical success was 50%-100% overall, 50%-100% for balloon-angioplasty-only and 100% for primary stenting. Long-term PV patency was 50%-100% overall, 37.5%-100% for balloon-angioplasty-only and 100% for primary stenting. Primary balloon angioplasty was successful in 78% of the cases. Of the recurrent PV stenoses, 9% resolved with stent placement and one required a meso-Rex shunt. There was one re-transplantation without stenting. The complication rate was 2.6% for balloon-angioplasty-only (bleeding, liver abscess, 2 PV thromboses) and 5.9% for primary stenting (bleeding, stent-fracture). There was no procedure-related mortality.

CONCLUSION

Percutaneous transhepatic balloon angioplasty may be the initial management of portal vein stenosis in paediatric liver recipients. Stent placement may be a primary option in selected cases and a reliable rescue option for recurrent portal vein stenosis following balloon-angioplasty-only.

Pediatric split liver transplantation for congenital factor X deficiency: first 10-year follow-up of a case with portal vein stenting

Congenital factor X (FX) deficiency is a rare autosomal-recessive disease that induces bleeding disorder. Herein, we present the 10-year posttransplant course of a pediatric patient who underwent liver transplantation (LT) with portal vein (PV) stenting for correction of severe congenital FX deficiency, with focus on long-term maintenance of coagulation function and patency of PV stenting. A 17-month-old infant with recurrent hemorrhagic episodes due to FX deficiency underwent split LT using a left lateral section graft. The graft-recipient weight ratio was 2.2%. The graft implantation procedures were performed by following the standard pediatric split LT procedure. Nevertheless, a wall stent was inserted due to PV anastomotic stenosis on posttransplant day 1. Graft function recovered slowly because of partial parenchyma infarct, and the patient was discharged at 46 days after LT operation. The FX activity started to increase soon after LT and gradually normalized; the coagulation profiles have been maintained well for the past 10 years. The patient has been doing well for the past 10 years after LT without any episodes of abnormal bleeding. Due to the risk of vascular complications owed to PV stenting, life-long follow-up is mandatory with special attention until attainment of complete physical growth to adolescent and adulthood.

The Application of Interventional Radiology in Living-Donor Liver Transplantation

Owing to improvements in surgical techniques and medical care, living-donor liver transplantation has become an established treatment modality in patients with end-stage liver disease. However, various vascular or non-vascular complications may occur during or after transplantation. Herein, we review how interventional radiologic techniques can be used to treat these complications.

Safety and Efficacy of Endovascular Treatment of Portal Vein Stenosis in Liver Transplant Recipients: A Systematic Review

PURPOSE

To evaluate the efficacy of Angioplasty and Stent Placement for the treatment of Portal Vein Stenosis in Liver Transplant Recipients by performing a systematic review.

MATERIALS AND METHODS

The PubMed Database was extensively searched for articles describing Portal Vein Stenosis (PVS) as a complication in Liver Transplant (LT) patients. The initial database search yielded 488 unique records published in the PubMed Database, 19 of which were deemed to meet the inclusion criteria. Outcomes were separated into 2 groups (Group A included patients with primary angioplasty, Group B included patients with primary stent placement), and further subdivided into Adult and Pediatric populations.

RESULTS

Group A included a total of 282 LT patients with portal vein stenosis. The population was predominantly pediatric (n = 243). Group B included a total of 111 LT patients with portal vein stenosis. This population was predominantly adult (n = 66). Technical success was significantly higher in both Group B pediatric (100%) and adults (97%) compared to Group A (69.5%) and (66.7%) respectively. Re-stenosis rates were significantly lower in Group B pediatric group compared to Group A (2.3% vs 29.7%, χ² = 13.9; p < 0.001). Overall major (3.1%) and minor complications rates (1.5%) were low.

CONCLUSION

Primary stent placement appears to have higher technical success in both populations and lower re-stenosis rates for treatment of PVS in pediatric populations.

Direct transmesenteric venous interventions in the acute post liver transplant setting

INTRODUCTION

Portal venous thrombosis and stenosis are uncommon but serious causes of liver transplant graft failure. While surgical thrombectomy can be utilized for the treatment of portal steno-occlusive disease, venous interventions with IR have been performed with encouraging results.

CASE DESCRIPTION

69-year-old female with non-alcoholic steatohepatitis cirrhosis who received a liver transplant complicated by portal vein thrombus. Efforts between transplant surgery and IR allowed for successful thrombus removal via direct SMV access.

RESULTS

The advantages of direct SMV access with the surgery team include direct approach to accessing thrombus, sparing of liver parenchyma, and significant hemostatic control.

Liver Transplantation in Children: An Overview of Organ Allocation and Surgical Management

Liver transplantation is the standard treatment for children with end-stage liver disease, primary hepatic neoplasms, or liver-localized metabolic defects. Perioperative mortality is almost absent, and long-term survival exceeds 90%. Organ shortage is managed thanks to advances in organ retrieval techniques; living donation and partial liver transplantation almost eliminated waiting list mortality, thus leading to expanding indications for transplantation. The success of pediatric liver transplantation depends on the prompt and early referral of patients to transplant Centers and on the close and integrated multidisciplinary collaboration between pediatricians, hepatologists, surgeons, intensivists, oncologists, pathologists, coordinating nurses, psychologists, and social workers.

Transhepatic stent placement for portal vein obstruction after hepatobiliary and pancreatic surgery: long-term efficacy and risk factor for stent failure

OBJECTIVES

To evaluate the long-term efficacy of transhepatic portal vein (PV) stent placement in patients with postoperative PV obstruction and to identify risk factors for stent failure.

METHODS

Between January 2007 and October 2019, percutaneous transhepatic PV stent placement was attempted in 60 patients with postoperative PV obstruction. Technical and clinical success, complications, and stent patency were retrospectively evaluated. Thirteen clinical variables were analyzed to determine risk factors for stent failure.

RESULTS

Stent placement was technically successful in all patients. Thromboaspiration (n = 19) and jejunal variceal embolization (n = 7) were performed in the same session. Clinical symptoms related to portal hypertension were resolved in 54 patients (90.0%). There was no procedure-related complication. During the follow-up period (mean 630 days), stent failure occurred in 13 patients. One- and 5-year stent patency rate was 74.8% and 64.9%, respectively. The presence of a pancreatic fistula was the only independent risk factor associated with stent failure (HR 7.54; 95% CI 2.02-28.10, p = 0.003).

CONCLUSIONS

Percutaneous transhepatic PV stent placement is a technically feasible and effective treatment for postoperative PV obstruction. The pancreatic fistula is a risk factor for stent failure.

KEY POINTS

• Percutaneous transhepatic stent placement is an effective treatment to improve portal hypertension-related symptoms in patients with portal vein obstruction after hepatobiliary and pancreatic surgery. • The pancreatic fistula is an independent risk factor for portal vein stent failure.

The devil is in the detail: current management of perioperative surgical complications after liver transplantation

PURPOSE OF REVIEW

Despite advances in the field, perioperative morbidity is common after liver transplantation. This review examines the current literature to provide up-to-date management of common surgical complications associated with liver transplantation.

RECENT FINDINGS

Research focuses on problems with anastomoses of the vena cava, portal vein, hepatic artery, and bile ducts. Interventional endoscopic and radiological techniques are used more frequently to avoid reoperation.

SUMMARY

Advances in the management of perioperative surgical complications have focused on minimally invasive measures that successfully treat technical problems with implantation of liver allografts from both living and deceased donors.

Stent insertion and balloon angioplasty for portal vein stenosis after liver transplantation: long-term follow-up results

PURPOSE

It is not easy to determine whether balloon angioplasty or stenting should be performed in patients with portal vein stenosis after liver transplantation. We aimed to propose appropriate indication by evaluating long-term outcomes of balloon angioplasty and stent insertion in adult liver transplant patients.

METHODS

We retrospectively reviewed 31 patients with portal vein stenosis among 1369 patients who underwent adult liver transplantation from January 2001 to December 2015. When stenosis was confirmed by venography, angioplasty was performed first. When there was no flow improvement or pressure gradient was not decreased after angioplasty, stent insertion was performed. We also performed primary stent insertion without angioplasty for diffuse stenosis, kinking, external compression, and near occlusion of portal vein in venography. We assessed patency in patients who underwent percutaneous transluminal angioplasty and stent insertion through regular outpatient follow-up and evaluated technical and clinical success and long-term results.

RESULTS

Technical success was 85% and 100% in balloon angioplasty and stent insertion, respectively. Clinical success was achieved in 78% of balloon angioplasties and in 100% of stent insertions. At 1, 5, and 10 years after balloon angioplasty, patency rates were 87%, 82%, and 68% respectively, and the rates of stent patency were all 100%. Portal vein size measured during the operation of patients with and without recurrence were 19±4.2 mm and 19±3.0 mm (P = 0.956), respectively. The balloon size of patients with and without recurrence were 11±1.95 mm and 14±1.66 mm, respectively (P = 0.013), when balloon angioplasty was performed after stenosis diagnosis.

CONCLUSION

Stent insertion can be considered when fibrotic changes are expected due to repeated inflammation and when the balloon size to be used is small. Balloon angioplasty seems less risky for anastomotic ruptures in portal vein stenosis in the early post liver transplantation period.

Pediatric Hepatobiliary Interventions in the Setting of Intrahepatic Vascular Malformations, Portal Hypertension, and Liver Transplant

Within the broad spectrum of pediatric hepatobiliary disorders, hepatic vascular malformations, portal hypertension, and hepatic transplant interventions pose numerous challenges. The role of interventional radiology within each of these conditions is discussed herein, beginning with endovascular management of high flow hepatic vascular malformations. Next, while becoming less common in adult populations, surgical portoportal and portosystemic shunts remain prevalent in many pediatric centers. Shunt anatomy is reviewed along with endovascular management techniques for shunt dysfunction. Next, the growing experience with pediatric transjugular intrahepatic portosystemic shunt placement is reviewed along with tips for success in pediatric patients. Finally, pediatric hepatic transplant interventions are discussed with technical notes pertinent to split liver anatomy.

Endovascular treatment of surgical mesoportal and portosystemic shunt dysfunction in pediatric patients

BACKGROUND

Published data describing the endovascular treatment of dysfunctional mesoportal and portosystemic shunts in the pediatric population are limited.

OBJECTIVE

We sought to describe the treatment and follow-up of such shunts managed by interventional radiology at a single pediatric hospital. We hypothesized that stenotic and occluded pediatric portosystemic and mesoportal shunts can be maintained patent by interventional radiology in the moderate term.

MATERIALS AND METHODS

We conducted a single-center retrospective study at a tertiary pediatric hospital. We included children with surgical mesoportal (meso-Rex) or portosystemic (mesocaval, splenorenal or splenocaval) shunts treated with attempted angioplasty or stenting from 2010 to 2018. Technical success was defined as catheterization and intervention upon the shunt with venographic evidence of flow improvement. The primary outcome variables were shunt patency at 1 month, 6 months, 12 months and 24 months post-procedure and freedom from reintervention.

RESULTS

Twenty pediatric patients (11 boys, 9 girls; mean age 8.25 years, range 1.3-17 years) met inclusion criteria. Fifty-two interventions (primary and reintervention) on 13 splenorenal, 3 meso-Rex, 2 mesocaval and 2 splenocaval shunts were performed because of evidence of shunt failure, including gastrointestinal bleeding, hypersplenism, or radiographic evidence of a flow defect. The 11 stenotic shunts were treated with 100% technical success, while the remaining 9 occluded shunts were treated with 66.7% technical success. The mean number of reinterventions was 1.9 (standard deviation [SD] = 3.1) per child, which did not differ between stenotic and occluded shunts (P=0.24). Primary patency at 1-month, 6-month, 12-month and 24-months follow-up visits was 17/17 (100%), 10/16 (62.5%), 7/15 (46.7%) and 4/10 (40%), respectively. However, 100% of shunts were either primary patent or primary-assisted patent by endovascular reintervention. There were no cases of shunt occlusion following initial technical success. Finally, the median freedom from reintervention duration was 387 days (SD=821 days).

CONCLUSION

Dysfunctional portosystemic surgical shunts are effectively managed by endovascular methods. While many shunts require reintervention, combined primary patency and assisted primary patency rates are excellent.

Recanalization of Chronic Portal Vein Occlusion in Pediatric Liver Transplant Patients

PURPOSE

To evaluate technical and clinical success and report long-term outcomes of portal vein (PV) recanalization in pediatric orthotopic liver transplant (OLT) patients with chronic PV occlusion.

MATERIALS AND METHODS

This is a retrospective review of 15 OLT patients (5 males) with chronic PV occlusion who underwent PV recanalization (33 procedures) between October 2011 and February 2018. Median age was 4.5 years (range, 1-16 years); median weight was 16.6 kg (range, 11.5-57.3 kg). Median time interval from OLT to first intervention was 3.25 years (range, 0.6-15.7 years). Clinical presentations included hypersplenism (n = 12), gastrointestinal bleeding (n = 9), and ascites (n = 3). One patient had incidental diagnosis of PV occlusion. Primary, primary-assisted, and secondary patency at 3, 6, 12, and 24 months were evaluated.

RESULTS

Technically successful PV recanalization and reduction of PV pressure gradient to ≤ 5 mm Hg was performed in 13/15 patients (87%). Ten of 15 (67%) patients had successful recanalization with the first attempt. Clinical success, defined as improvement in signs and symptoms of portal hypertension, was achieved in 12/13 (92%) patients. Five of 33 (15%) major complications (Society of Interventional Radiology class C), including perisplenic hematoma (n = 2), hemoperitoneum (n = 2), and hepatic artery pseudo aneurysm (n = 1), were managed with pain medication and blood product replacement. Median follow-up was 22 months (range, 1-77 months). Median primary patency was 5 months. Primary patency at 3, 6, 12, and 24 months was 53.8%, 46.2%, 38.5%, and 30.8%, respectively. Primary-assisted patency was 84.6%, 76.9%, 53.8%, and 46.2%, respectively. Secondary patency was 92.3%, 84.6%, 53.8%, and 46.2%, respectively.

CONCLUSIONS

PV recanalization is a safe and effective minimally invasive option in the management of chronic PV occlusion after pediatric OLT.