Percutaneous Endovascular Treatment of Hepatic Artery Stenosis in Adult and Pediatric Patients After Liver Transplantation

Hepatic artery stenosis after pediatric liver transplantation: The potential role of conservative management

AIM

This study aimed to investigate the outcomes and effectiveness of various treatment strategies in patients with hepatic artery stenosis (HAS) after pediatric liver transplantation (pLT).

METHODS

This is a single center observational cohort study between January 1st, 2004 and August 1st, 2023, including pLT recipients aged <18 years. The primary outcome was graft and patient survival. The secondary outcomes included incidence of biliary complications, technical success of surgery or endovascular therapy (EVT), and changes in liver function. The cut-off for early and late HAS was 14 days after pLT.

RESULTS

Among a total of 327 pLT patients, 4 % (n = 13) developed HAS (n = 3 early; n = 10 late). Treatments included surgical revascularization for one early HAS, conservative management with anticoagulation for one early and four late HAS, and EVT for one early and six late HAS. Over a median follow-up of 28.2 months after the diagnosis of HAS, graft survival was 100 % and 83 % in early and late HAS groups, and patient survival reached 100 % in both groups. One graft loss occurred in the conservative group. Conversely, graft survival in the EVT group was 100 %.

CONCLUSION

The long-term outcomes of HAS after pLT are excellent. Both EVT and conservative management exhibited high graft survival rates for late HAS, with EVT achieving high technical success.

Incidence, management and outcomes in hepatic artery complications after paediatric liver transplantation: protocol of the retrospective, international, multicentre HEPATIC Registry

INTRODUCTION

Hepatic artery complications (HACs), such as a thrombosis or stenosis, are serious causes of morbidity and mortality after paediatric liver transplantation (LT). This study will investigate the incidence, current management practices and outcomes in paediatric patients with HAC after LT, including early and late complications.

METHODS AND ANALYSIS

The HEPatic Artery stenosis and Thrombosis after liver transplantation In Children (HEPATIC) Registry is an international, retrospective, multicentre, observational study. Any paediatric patient diagnosed with HAC and treated for HAC (at age <18 years) after paediatric LT within a 20-year time period will be included. The primary outcomes are graft and patient survivals. The secondary outcomes are technical success of the intervention, primary and secondary patency after HAC intervention, intraprocedural and postprocedural complications, description of current management practices, and incidence of HAC.

ETHICS AND DISSEMINATION

All participating sites will obtain local ethical approval and (waiver of) informed consent following the regulations on the conduct of observational clinical studies. The results will be disseminated through scientific presentations at conferences and through publication in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

The HEPATIC registry is registered at the ClinicalTrials.gov website; Registry Identifier: NCT05818644.

Treatment strategies for hepatic artery complications after pediatric liver transplantation: A systematic review

This study aimed to evaluate the effectiveness of different treatments for hepatic artery thrombosis (HAT) and hepatic artery stenosis (HAS) after pediatric liver transplantation. We systematically reviewed studies published since 2000 that investigated the management of HAT and/or HAS after pediatric liver transplantation. Studies with a minimum of 5 patients in one of the treatment methods were included. The primary outcomes were technical success rate and graft and patient survival. The secondary outcomes were hepatic artery patency, complications, and incidence of HAT and HAS. Of 3570 studies, we included 19 studies with 328 patients. The incidence was 6.2% for HAT and 4.1% for HAS. Patients with an early HAT treated with surgical revascularization had a median graft survival of 45.7% (interquartile range, 30.7%-60%) and a patient survival of 61.3% (interquartile range, 58.7%-66.9%) compared with the other treatments (conservative, endovascular revascularization, or retransplantation). As for HAS, endovascular and surgical revascularization groups had a patient survival of 85.7% and 100% (interquartile range, 85%-100%), respectively. Despite various treatment methods, HAT after pediatric liver transplantation remains a significant issue that has profound effects on the patient and graft survival. Current evidence is insufficient to determine the most effective treatment for preventing graft failure.

Vascular Complications After Liver Transplantation

OBJECTIVES

Vascular complications after liver transplant can be lethal. High levels of suspicion and aggressive use of diagnostic tools may help with early diagnosis and treatment. Here, we share our experiences regarding this topic.

MATERIALS AND METHODS

Adult and pediatric patients who had liver transplant between February 1997 and June 2018 in our clinic were included in the study. Patients were grouped according to age (pediatric patients were those under 18 years old), male versus female, indication for transplant, type of liver transplant, type of vascular complication, treatment, and survival aftertreatment.We analyzed the statistical incidence of vascular complications according to age, male versus female, and type of liver transplant.

RESULTS

Our analyses included 607 liver transplant procedures, including 7 retransplants, with 349 (57.4%) from living donors and 258 (42.6%) from deceased donors. Of total patients, 539 were adults (89.8%) and 61 were children (10.2%). Vascular complications occurred in 25 patients (4.1%), with hepatic artery complications seen in 13 patients (2.1%) (10 adults [1.8%] and 3 children [4.9%]), portal vein complications seen in 9 patients (1.5%) (6 adults [1.1%] and 3 children [4.9%]), and hepatic vein complications seen in 3 patients (0.5%) (2 adults [0.36%] and 1 child [1.6%]). Rate of vascular complications was statistically higher in pediatric patients (11.4% vs 3.3%; P = .007) and higher but not statistically in recipients of livers from living donors (5.2% vs 2.7%; P = .19). Twelve patients (48.8%) were treated with endovascular approach, and 11 (0.44%)required surgicaltreatment. Two patients underwent immediate retransplant due to hepatic artery thrombosis.

CONCLUSIONS

Because vascular complications are the most severe complications afterlivertransplant,there must be close follow-up of vascular anastomoses, particularly early postoperatively, with radiologic methods. In cases of vascular complications, emergent treatment, including endovascular interventions, surgery, and retransplant, must be performed.

Neuroform EZ Stents for Hepatic Artery Stenosis After Liver Transplantation: A Single-Center Preliminary Report

PURPOSE

This preliminary study evaluated the safety and effectiveness for off-label use of Neuroform EZ (NEZ) stents in the revascularization of hepatic artery stenosis (HAS) after orthotopic liver transplantation (OLT).

MATERIALS AND METHODS

Nine of 489 (5%) OLTs with HAS were managed with NEZ stents between September 2016 and July 2021. Stenting outcomes were evaluated based on the technical success rate, procedure-related complications, and primary patency.

RESULTS

A total of 10 NEZ stents (4.5 mm × 3 cm, n = 6; 4 mm × 3 cm, n = 4) were successfully deployed in 9 torturous hepatic arteries and in 1 relatively straight artery without any procedure-related complications. Combined thrombolysis (n = 3) and balloon angioplasty (n = 6) was performed. The median duration of follow-up was 438 days (range, 120-1126 days). Asymptomatic re-stenoses were detected in 2 stents on days 60 and 433 after stenting. A Kaplan-Meier curve predicted cumulative primary stent patencies at 1, 2, and 3 years of 90%, 75%, and 75%, respectively.

CONCLUSION

NEZ stents can be safely used to treat HAS after OLT with high technical success and favorable primary patency.

Management and outcome of hepatic artery thrombosis after pediatric liver transplantation

BACKGROUND

Pediatric LT are at particular risk of HAT, and its management still constitutes a matter of debate. Our purpose was to study predisposing factors and outcome of HAT post-LT, including the impact of surgical revisions on survival and biliary complications.

METHODS

Among 882 primary pediatric LT performed between 1993 and 2015, 36 HAT were encountered (4.1%, 35 fully documented). Each HAT case was retrospectively paired with a LT recipient without HAT, according to diagnosis, age at LT, type of graft, and era.

RESULTS

Five-year patient survivals were 77.0% versus 83.9% in HAT and non-HAT paired groups, respectively (P = .321). Corresponding graft survivals were 20.0% versus 80.5% (P < .001), and retransplantation rates 77.7% versus 10.7%, respectively (P < .001). One-year biliary complication-free survivals were 16.6% versus 83.8% in the HAT and non-HAT groups, respectively (P < .001). Regarding chronology of surgical re-exploration, only HAT cases that occurred within 14 days post-LT were re-operated, fourteen of them being explored within 7 days post-LT (revascularization rate: 6/14), versus two beyond 7 days (no revascularization). When revascularization was achieved, graft and biliary complication-free survival rates at 1 year were 33.3% and 22.2%, respectively, both rates being 0.0% in case of failure.

CONCLUSIONS

The pejorative prognosis associated with HAT in terms of graft survival is confirmed, whereas patient survival could be preserved through retransplantation. Results suggest that HAT should be re-operated if occurring within 7 days post-LT, but not beyond.

Clinical and Molecular-Based Approach in the Evaluation of Hepatocellular Carcinoma Recurrence after Radical Liver Resection

BACKGROUND

Hepatic resection remains the treatment of choice for patients with early-stage HCC with preserved liver function. Unfortunately, however, the majority of patients develop tumor recurrence. While several clinical factors were found to be associated with tumor recurrence, HCC pathogenesis is a complex process of accumulation of somatic genomic alterations, which leads to a huge molecular heterogeneity that has not been completely understood. The aim of this study is to complement potentially predictive clinical and pathological factors with next-generation sequencing genomic profiling and loss of heterozygosity analysis.

METHODS

124 HCC patients, who underwent a primary hepatic resection from January 2016 to December 2019, were recruited for this study. Next-generation sequencing (NGS) analysis and allelic imbalance assessment in a case-control subgroup analysis were performed. A time-to-recurrence analysis was performed as well by means of Kaplan-Meier estimators.

RESULTS

Cumulative number of HCC recurrences were 26 (21%) and 32 (26%), respectively, one and two years after surgery. Kaplan-Meier estimates for the probability of recurrence amounted to 37% (95% C.I.: 24-47) and to 51% (95% C.I.: 35-62), after one and two years, respectively. Multivariable analysis identified as independent predictors of HCC recurrence: hepatitis C virus (HCV) infection (HR: 1.96, 95%C.I.: 0.91-4.24, p = 0.085), serum bilirubin levels (HR: 5.32, 95%C.I.: 2.07-13.69, p = 0.001), number of nodules (HR: 1.63, 95%C.I.: 1.12-2.38, p = 0.011) and size of the larger nodule (HR: 1.11, 95%C.I.: 1.03-1.18, p = 0.004). Time-to-recurrence analysis showed that loss of heterozygosity in the PTEN loci (involved in the PI3K/AKT/mTOR signaling pathway) was significantly associated with a lower risk of HCC recurrence (HR: 0.35, 95%C.I.: 0.13-0.93, p = 0.036).

CONCLUSIONS

multiple alterations of cancer genes are associated with HCC progression. In particular, the evidence of a specific AI mutation presented in 20 patients seemed to have a protective effect on the risk of HCC recurrence.

Case report: Trans-papillary free stenting of the cystic duct and of the common bile duct in a double biliary ducts anastomoses of a right lobe living donor transplantation

Background

One of the major issues related to the living donor liver transplantation recipient outcome is still the high rate of biliary complication, especially when multiple biliary ducts are present and multiple anastomoses have to be performed.

Case presentation and conclusion

We report a case of adult-to-adult right lobe living donor liver transplantation performed for a recipient affected by alcohol-related cirrhosis with MELD score of 17. End-stage liver disease was complicated by refractory ascites, portal hypertension, small esophageal varices and portal gastropathy, hypersplenism, and abundant right pleural effusion. Here in the attached video we described the adult-to-adult LDLT procedures, where a right lobe with two biliary ducts draining respectively the right anterior and the right posterior segments has been transplanted. LDLT required a biliary reconstruction using the native cystic and common bile ducts stented trans-papillary with two 5- French 6 cm long soft silastic catheter. None major complications were detected during post-operative clinical courses. Actually, the donor and the recipient are alive and well. The technique we describe in the video, allow to keep the biliary anastomoses protected and patent without having the risk of creating cholestasis and the need of invasive additional procedure. No living donor right lobe transplantation should be refused because of the presence of multiple biliary ducts.

Pharmacokinetics of human antithrombin III concentrate in the immediate postoperative period after liver transplantation

AIMS

Antithrombin III (AT-III) concentrates have been used to prevent critical thrombosis in the immediate post-liver transplantation period without clear evidence regarding the optimal dose or administration scheme. The relationship between the AT-III dosage and the plasma activity levels during the period was evaluated in this study.

METHODS

The plasma AT-III activity levels and clinical data obtained from patients who received liver transplantation from January 2017 to September 2018 were retrospectively analysed. A population pharmacokinetic (PK) model was developed using nonlinear mixed-effects method and externally validated thereafter. Several dosing scenarios were simulated to maintain the plasma AT-III activity level within the normal range using the developed PK model to search for an optimal AT-III dosing regimen.

RESULTS

The plasma AT-III activity levels were best described by a single compartment model with first order elimination kinetics. The recovery of endogenous AT-III level during the postoperative days was modelled using an E_max model. The typical values (95% confidence interval) of volume of distribution and clearance were 3.86 (3.40-4.32) L, and 0.129 (0.111-0.147) L h^-1 , respectively. Serum albumin and body weight had significant effect on clearance and were included in the model. External validation of the proposed model demonstrated adequate prediction performance. Furthermore, simulation of previously suggested or modified dosing scenarios showed successful maintenance of AT-III activity level within the normal range.

CONCLUSION

A population PK model of AT-III concentrate was developed using data from liver recipients. Dosing scenarios simulated in our study may help establish a practical guide for AT-III concentrate titration after liver transplantation.

Catheter directed hepatic artery thrombolysis following liver transplantation. Case report and review of the literature

Hepatic artery thrombosis is the most frequent vascular complication following orthotopic liver transplantation, and often results in biliary complications, early graft loss and death. Surgical revascularization and retransplantation are considered the mainstay of treatment. However, intraarterial endovascular therapy is an alternative that has shown low morbidity and mortality, thereby avoiding the need for retransplantation. We describe a case of orthotopic liver transplantation complicated with hepatic artery thrombosis that was successfully treated with endovascular therapy.

Complications after endovascular treatment of hepatic artery stenosis after liver transplantation

BACKGROUND

Hepatic artery stenosis (HAS) after liver transplantation can progress to hepatic artery thrombosis (HAT) and a subsequent 30% to 50% risk of graft loss. Although endovascular treatment of severe HAS after liver transplantation has emerged as the dominant method of treatment, the potential risks of these interventions are poorly described.

METHODS

A retrospective review of all endovascular interventions for HAS after liver transplantation between August 2009 and March 2016 was performed at a single institution, which has the largest volume of liver transplants in the United States. Severe HAS was identified by routine surveillance duplex ultrasound imaging (peak systolic velocity >400 cm/s, resistive index <0.5, and presence of tardus parvus waveforms).

RESULTS

In 1129 liver transplant recipients during the study period, 106 angiograms were performed in 79 patients (6.9%) for severe de novo or recurrent HAS. Interventions were performed in 99 of 106 cases (93.4%) with percutaneous transluminal angioplasty alone (34 of 99) or with stent placement (65 of 99). Immediate technical success was 91%. Major complications occurred in eight of 106 cases (7.5%), consisting of target vessel dissection (5 of 8) and rupture (3 of 8). Successful endovascular treatment was possible in six of the eight patients (75%). Ruptures were treated with the use of a covered coronary balloon-expandable stent graft or balloon tamponade. Dissections were treated with placement of bare-metal or drug-eluting stents. No open surgical intervention was required to manage any of these complications. With a median of follow-up of 22 months, four of eight patients (50%) with a major complication progressed to HAT compared with one of 71 patients (1.4%) undergoing a hepatic intervention without a major complication (P < .001). One patient required retransplantation. Severe vessel tortuosity was present in 75% (6 of 8) of interventions with a major complication compared with 34.6% (34 of 98) in those without (P = .05). In the complication cohort, 37.5% (3 of 8) of the patients had received a second liver transplant before intervention compared with 12.6% (9 of 71) of the patients in the noncomplication cohort (P = .097).

CONCLUSIONS

Although endovascular treatment of HAS is safe and effective in most patients, target vessel injury is possible. Severe tortuosity of the hepatic artery and prior retransplantation were associated with a twofold to threefold increased risk of a major complication. Acute vessel injury can be managed successfully using endovascular techniques, but these patients have a significant risk of subsequent HAT and need close surveillance.

Percutaneous Retrograde Transhepatic Arterial Puncture to Regain Access in the True Lumen of the Dissected and Acutely Occluded Transplant Hepatic Artery

Iatrogenic hepatic artery dissection is a serious complication that can progress to complete hepatic artery occlusion and graft loss. Restoration of arterial flow to the graft is urgent, but the severity and extent of the dissection may interfere with endovascular techniques. The authors describe a technique of percutaneous retrograde transhepatic arterial puncture to regain access into the true lumen of the dissected hepatic artery to restore in-line flow to the liver graft.

Intention-to-treat analysis of percutaneous endovascular treatment of hepatic artery stenosis after orthotopic liver transplantation

Hepatic artery stenosis (HAS) is a rare complication of orthotopic liver transplantation (LT). HAS could evolve into complete thrombosis and lead to graft loss, incurring significant morbidity and mortality. Even though endovascular management by percutaneous transluminal angioplasty ± stenting (PTA) is the primary treatment of HAS, its longterm impact on hepatic artery (HA) patency and graft survival remains unclear. This study aimed to evaluate longterm outcomes of PTA and to define the risk factors of treatment failure. From 2006 to 2012, 30 patients with critical HAS (>50% stenosis of HA) and treated by PTA were identified from 870 adult patients undergoing LT. Seventeen patients were diagnosed by post-LT screening, and 13 patients were symptomatic due to HAS. PTA was completed successfully in 27 (90%) patients with angioplasty plus stenting in 23 and angioplasty alone in 4. The immediate technical success rate was 90%. A major complication that was observed was arterial dissection (1 patient) which eventually necessitated retransplantation. Restenosis was observed in 10 (33%) patients. One-year, 3-year, and 5-year HA patency rates were 68%, 62.8%, and 62.8%, respectively. Overall patient survival was 93.3% at 3 years and 85.3% at 5 years. The 3-year and 5-year liver graft survival rates were 84.7% and 64.5%, respectively. No significant difference was observed in patient and graft survivals between asymptomatic and symptomatic patients after PTA. Similarly, no difference was observed between angioplasty alone and angioplasty plus stenting. In conclusion, endovascular therapy ensures a good 5-year graft survival (64.5%) and patient survival (85.3%) in patients with critical HAS by maintaining HA patency with a low risk of serious morbidity (3.3%). Liver Transplantation 22 923-933 2016 AASLD.

Hepatic arterial and portal venous complications after adult and pediatric living donor liver transplantation, risk factors, management and outcome (A retrospective cohort study)

OBJECTIVES

Hepatic arterial (HA) and portal venous (PV) complications of recipients after living donor liver transplantation(LDLT) result in patient loss. The aim of this study was to analyze these complications.

METHODS

We retrospectively analyzed HA and/or PV complications in 213 of 222 recipients underwent LDLT in our centre. The overall male/female and adult/pediatric ratios were 183/30 and 186/27 respectively.

RESULTS

The overall incidence of HA and/or PV complications was 19.7% (n = 42), while adult and pediatric complications were 18.3% (n = 39) and 1.4% (n = 3) respectively. However early (<1month) and late (>1month) complications were 9.4% (n = 20) and 10.3% (n = 22) respectively. Individually HA problems (HA stenosis, HA thrombosis, injury and arterial steal syndrome) 15% (n = 32), PV problems (PV thrombosis and PV stenosis) 2.8% (n = 6) and simultaneous HA and PV problems 1.9% (n = 4). 40/42 of complications were managed by angiography (n = 18), surgery (n = 10) or medically (Anticoagulant and/or thrombolytic) (n = 12) where successful treatment occurred in 18 patients. 13/42 (31%) of patients died as a direct result of these complications. Preoperative PVT was significant predictor of these complications in univariate analysis. The 6-month, 1-, 3-, 5- 7- and 10-year survival rates in patients were 65.3%, 61.5%, 55.9%, 55.4%, 54.5% and 54.5% respectively.

CONCLUSION

HA and/or PV complications specially early ones lead to significant poor outcome after LDLT, so proper dealing with the risk factors like pre LT PVT (I.e. More intensive anticoagulation therapy) and the effective management of these complications are mandatory for improving outcome.

Hepatic arterial and portal venous complications after adult and pediatric living donor liver transplantation, risk factors, management and outcome (A retrospective cohort study)

Objectives

Hepatic arterial (HA) and portal venous (PV) complications of recipients after living donor liver transplantation(LDLT) result in patient loss. The aim of this study was to analyze these complications.

Methods

We retrospectively analyzed HA and/or PV complications in 213 of 222 recipients underwent LDLT in our centre. The overall male/female and adult/pediatric ratios were 183/30 and 186/27 respectively.

Results

The overall incidence of HA and/or PV complications was 19.7% (n = 42), while adult and pediatric complications were 18.3% (n = 39) and 1.4% (n = 3) respectively. However early (<1month) and late (>1month) complications were 9.4% (n = 20) and 10.3% (n = 22) respectively. Individually HA problems (HA stenosis, HA thrombosis, injury and arterial steal syndrome) 15% (n = 32), PV problems (PV thrombosis and PV stenosis) 2.8% (n = 6) and simultaneous HA and PV problems 1.9% (n = 4). 40/42 of complications were managed by angiography (n = 18), surgery (n = 10) or medically (Anticoagulant and/or thrombolytic) (n = 12) where successful treatment occurred in 18 patients. 13/42 (31%) of patients died as a direct result of these complications. Preoperative PVT was significant predictor of these complications in univariate analysis. The 6-month, 1-, 3-, 5- 7- and 10-year survival rates in patients were 65.3%, 61.5%, 55.9%, 55.4%, 54.5% and 54.5% respectively.

Conclusion

HA and/or PV complications specially early ones lead to significant poor outcome after LDLT, so proper dealing with the risk factors like pre LT PVT (I.e. More intensive anticoagulation therapy) and the effective management of these complications are mandatory for improving outcome.

•

Preoperative PVT was significant predictor of HA and/or PV complications.

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HA and/or PV complications especially early ones lead to significant poor outcome.

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Proper dealing with the risk factors like pre LT PVT improves outcome.

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The effective management of these complications is mandatory for improving outcome.

Primary stent placement for hepatic artery stenosis after liver transplantation

OBJECTIVE

Significant hepatic artery stenosis (HAS) after orthotopic liver transplantation (OLT) can lead to thrombosis, with subsequent liver failure in 30% of patients. Although operative intervention or retransplantation has been the traditional solution, endovascular therapy has emerged as a less invasive treatment strategy. Prior smaller studies have been conflicting in the relative efficacy of percutaneous transluminal angioplasty (PTA) vs primary stent placement for HAS.

METHODS

This was a single-center retrospective review of all endovascular interventions for HAS after OLT during a 54-month period (August 2009-December 2013). Patients with ultrasound imaging with evidence of severe HAS (peak systolic velocity >400-450 cm/s, resistive index <0.5) underwent endovascular treatment with primary stent placement or PTA. Outcomes calculated were technical success, primary and primary assisted patency rates, reinterventions, and complications.

RESULTS

Sixty-two interventions for HAS were performed in 42 patients with a mean follow-up of 19.1 ± 15.2 months. During the study period, 654 OLTs were performed. Of 61 patients diagnosed with HAS, 42 underwent an endovascular intervention. The rate of endovascularly treated HAS was 6.4% (42 of 654). Primary technical success was achieved in 95% (59 of 62) of the interventions. Initial treatment was with PTA alone in 17 or primary stent in 25. Primary patency rates after initial stent placement were 87%, 76.5%, 78%, and 78% at 1, 6, 12, and 24 months, respectively, compared with initial PTA rates of 64.7%, 53.3%, 40%, and 0% (P = .19). There were 20 reinterventions in 14 patients (eight stents, six PTAs). The time to the initial reintervention was 51 days in patients with PTA alone vs 105.8 days for those with an initial stent (P = .16). Overall primary assisted patency was 93% at 24 months. Major complications were one arterial rupture and two hepatic artery dissections. The long-term risk of hepatic artery thrombosis in the entire patient cohort was 3.2%.

CONCLUSIONS

HAS after OLT can be treated endovascularly with high technical success and excellent primary assisted patency. This series represents the largest reported cohort of endovascular interventions for HAS to date. Initial use of a stent showed a strong trend toward decreasing the need for reintervention. Avoidance of hepatic artery thrombosis is possible in >95% of patients with endovascular treatment and close follow-up.

Current state of the art in management of vascular complications after pediatric liver transplantation

Vascular complications by compromising the blood flow to the allograft can have significant and sometimes life-threatening consequences after pediatric liver transplantation. High level of suspicion and aggressive utilization of diagnostic modalities can lead to early diagnosis and salvage of the allograft. This review will summarize the current trends in management of vascular complications after pediatric liver transplantation.

Percutaneous Endovascular Treatment for Hepatic Artery Stenosis after Liver Transplantation: The Role of Percutaneous Endovascular Treatment

BACKGROUND

To retrospectively analyze the outcomes of interventional radiology treatment of patients with hepatic artery stenosis (HAS) after liver transplantation at our Institution.

MATERIAL/METHODS

Hepatic artery stenosis was diagnosed and treated by endovascular technique in 8 (2.8%) patients, who underwent liver transplantation between July 2007 and July 2011. Patients entered the follow-up period, during which we analyzed hepatic artery patency with Doppler ultrasound at 1, 3, 6, and 12 months after percutaneous endovascular treatment (PTA), and every six months thereafter.

RESULTS

During the 12-month follow-up period, 6 out of 8 patients (75%) were asymptomatic with patent hepatic artery, which was confirmed by multislice computed tomography (MSCT) angiography, or color Doppler (CD) ultrasound. One patient had a fatal outcome of unknown cause, and one patient underwent orthotopic liver retransplantation (re-OLT) procedure due to graft failure.

CONCLUSIONS

Our results suggest that HAS angioplasty and stenting are minimally invasive and safe endovascular procedures that represent a good alternative to open surgery, with good 12-month follow-up patency results comparable to surgery.

Surgical and endovascular treatment of hepatic arterial complications following liver transplant

Vascular complications after liver transplantation increase post-operative morbidity and contribute to the incidence of retransplantation. Vascular complications comprise arterial, caval, and portal venous pathology, with the majority of complications being arterial in etiology, including anastomotic stricture, pseudoaneurysm, and thrombosis. There are two major therapeutic options for the treatment of these arterial complications: endovascular intervention and surgery. The former includes intra-arterial thrombolysis, embolization, percutaneous transluminal angioplasty, and stent placement. The latter includes thrombectomy, reanastomosis, and retransplantation. Although surgical treatment has been considered the first choice for management in the past, advances in endovascular intervention have increased and make it a viable therapeutic option following orthotopic liver transplantation. This review focuses on the role of surgical and endovascular therapy in the management of hepatic arterial complications after liver transplantation.

Low plasma levels of antithrombin III in the early post-operative period following pediatric liver transplantation: should they be replaced? A single-center pilot study

eHAT after LT remains a life-threatening complication. In the majority of anticoagulation protocols, heparin is used to prevent thromboses. Our study aimed to monitor AT-III levels in the early post-LT period to assess the need for the administration of AT-III concentrate to ensure the effectiveness of heparin. We monitored coagulation daily by measuring INR, APTT, fibrinogen, platelets, and AT-III. Anticoagulation therapy consisted of LMWH, AT-III, and dipyridamole. AT-III concentrate was administered when AT-III activity was ≤60%. DUS was performed daily for the first five post-operative days or whenever vascular thrombosis was suspected. Between October 2007 and October 2011, 39 LT were performed in our center. The median age was 26 months (6-196) with a median weight of 9 kg (5.5-49). AT-III activity was ≤60% in 27 patients. Lower levels were particularly observed in partial grafts and recipients weighing less than 10 kg. Patent arterial flow was present in all 39 LT during the first five post-operative days. AT-III levels were low in 70% of pediatric patients following LT, thereby risking heparin ineffectiveness. These results may implicate low AT-III levels in the etiology of eHAT post-LT. However, this is a small single-center pilot study and further larger prospective trials are required to confirm these results.

Risk factors and treatments for hepatic arterial complications in pediatric living donor liver transplantation

BACKGROUND

Hepatic artery complications (HAC) are a serious complication in pediatric liver transplant recipients because its incidence is high and it can occasionally lead to graft liver failure. We herein present a retrospective analysis of our 10-year experience with pediatric living donor liver transplantation (LDLT) focusing on the risk factors and treatments for HAC.

METHODS

Between May 2001 and November 2011, 209 LDLTs were performed for 203 pediatric recipients. We performed the multivariate analyses to identify the factors associated with HAC and showed the therapeutic strategy and outcome for HAC.

RESULTS

The overall incidence of HAC was 7.2%, and the graft survival of recipients with HAC was 73.3%. The multivariate analysis showed that the pediatric end-stage liver disease score (≥20), post-transplant laparotomy except for HAC treatment and extra-anatomical hepatic artery reconstruction were independent risk factors for HAC (P = 0.020, P = 0.015 and P = 0.002, respectively). Eleven surgical interventions and 13 endovascular interventions were performed for 15 recipients with HAC. The serum aspartate aminotransferase levels pre- and post-treatment for HAC were significantly higher in the surgical group than in the endovascular group (P = 0.016 and P = 0.022, respectively).

CONCLUSIONS

It is important for recipients with risk factors to maintain strict post-transplant management to help prevent HAC and detect it in earlier stages. Endovascular intervention can be a less invasive method for treating HAC than surgical intervention, and can be performed as an early treatment.

A comparison of open surgery and endovascular intervention for hepatic artery complications after pediatric liver transplantation

There are currently 2 major therapeutic options for the treatment of hepatic artery complications: endovascular intervention and open surgery. We herein report a retrospective analysis of 14 pediatric patients with hepatic artery complications after pediatric living donor liver transplantation (LDLT) at our institution. We divided them into an open surgery group and an endovascular intervention group based on their primary treatment, and compared the results and outcomes. We then evaluated which procedure is more effective and less invasive. In the open surgery group, recurrent stenosis or spasm of the hepatic artery occurred in 3 of the 8 patients (37.5%). In the endovascular intervention group, 5 of the 6 patients were technically successfully treated by only endovascular treatment. Of the 5 successfully treated patients, 3 developed recurrent stenosis (60%). There were significant differences in the mean length of the operation for the first treatment of hepatic artery complications (open surgery, 428 minutes vs endovascular intervention, 160 minutes; P = .01) and in the mean value of the posttreatment aspartate aminotransferase (AST)/alanine aminotransferase (ALT) (open surgery > endovascular intervention; P = .04/.05). Although endovascular intervention needs to be examined in further studies to reduce the rate of relapse, it is a less invasive method for the patient and graft than open surgery.

Stent placement versus angioplasty for hepatic artery stenosis after liver transplant: a meta-analysis of case series

BACKGROUND

Hepatic artery stenosis (HAS) is a serious complication of liver transplantation but data on the most effective endovascular management are lacking. We aimed to compare percutaneous balloon angioplasty (PBA) with stent placement.

METHODS

We searched MEDLINE, Cochrane, Web of Science, EMBASE, SCOPUS, and Biosis Previews between 1970 and December 2011 and performed meta-analysis of short-term (procedural success, complications) and long-term outcomes (liver function, arterial patency, survival, re-intervention, re-transplantation). Random effects models were used for the analysis and meta-regression performed for the year of study.

RESULTS

A total of 263 liver transplants in 257 patients [age 43 (±8) years] underwent 147 PBAs and 116 stents. Transplanted livers were from deceased donors in 240 (91 %). Follow-up was 1 month to 4.5 years (median 17 months). PBA and stent had similar procedural success (89 % vs. 98 %), complications (16 % vs. 19 %), normal liver function tests (80 % vs. 68 %), arterial patency (76 % vs. 68 %), survival (80 % vs. 82 %), and requirement for re-intervention (22 % vs. 25 %) or re-transplantation (20 % vs. 24 %) (P non-significant). In the most recent studies re-transplantation was reported less compared to older series (P = 0.04).

CONCLUSION

Both PBA and stent offer comparable results for HAS. These techniques have contributed to a recent decline in re-transplantation.

KEY POINTS

• Interventional radiological procedures are often used to treat post-transplant hepatic artery stenosis. • Meta-analysis shows that percutaneous balloon angioplasty and stent placement are both efficacious. • Percutaneous balloon angioplasty and stent placement appear to have similar complication rates. • Re-transplantation rates have declined, partly due to interventional management for arterial stenosis.

Repeat endovascular treatment of recurring hepatic artery stenoses in orthotopic liver transplantation

Hepatic artery stenosis (HAS) is a complication that impacts the results of orthotopic liver transplantation (OLT). Interventional radiological techniques are important therapeutic options for HAS. The aim of this retrospective study was to evaluate the outcome of repeated radiological treatments in recurring HAS after OLT. Of the 941 patients who underwent OLT at our center from January 1998 to September 2010, 48 (5%) were diagnosed with HAS, 37 (77%) of whom underwent transluminal interventional therapy with the placement of an endovascular stent. Success rate, complications, hepatic artery patency and follow-up were reviewed. After stent placement, artery patency was achieved in all patients. Three patients developed complications, including arterial dissection and hematoma. HAS recurrence was observed in 9 patients (24%), and hepatic artery thrombosis (HAT) occurred in 4 (11%). Radiological interventions were repeated 10 times in 8 patients without complications. At a median follow-up of 66 months (range 10-158), hepatic artery patency was observed in 35 cases (94.6%). The 5-year rates for graft and patient survival were 82.3% and 87.7%, respectively. Restenosis may occur in one-third of patients after endovascular treatment for thrombosis and HAS, but the long-term outcomes of iterative radiological treatment for HAS indicate a high rate of success.

Endovascular treatment of hepatic artery stenosis after liver transplantation

BACKGROUND

Hepatic artery stenosis (HAS) after orthotopic liver transplantation is a significant risk factor for subsequent hepatic artery thrombosis (HAT). HAT is associated with a 30%-50% risk of liver failure culminating in retransplantation or death. Traditional treatment of hepatic artery complications has been surgical, with hepatic artery revision or retransplantation. Endovascular therapy of HAS, described primarily in the interventional radiology literature, may provide a less-invasive treatment option.

METHODS

This was a retrospective review of all endovascular interventions performed for HAS after orthotopic liver transplantation over a 31-month period (August 2009 to January 2012). Patients with duplex ultrasound imaging evidence of severe main HAS (peak systolic velocity of >400 cm/s, resistive index of <.5) underwent endovascular treatment with either primary stent placement or percutaneous transluminal angioplasty (PTA) alone. Patients were followed with serial ultrasound imaging to assess for treatment success and late restenosis. Reintervention was performed if significant restenosis occurred.

RESULTS

Thirty-five hepatic artery interventions were performed in 23 patients. Over the 31-month study period, 318 orthotopic liver transplantations were performed, yielding a 7.4% (23/318) rate of hepatic artery intervention. Primary technical success was achieved in 97% (34/35) of cases. Initial treatment was with PTA alone (n = 10) or primary stent placement (n = 13). The initial postintervention ultrasound images revealed improvements in hepatic artery peak systolic velocity (267 ± 118 [posttreatment] vs 489.9 ± 155 cm/s [pretreatment]; P < .0001) and main hepatic artery resistive index (0.61 ± 0.08 [posttreatment] vs 0.41 ± 0.07 [pretreatment]; P < .0001). At a mean follow-up of 8.2 ± 1.8 months (range, 0-29), there were 12 reinterventions in 10 patients for recurrent HAS. Thirty-one percent (n = 4/13) of patients undergoing initial stent placement required reintervention (at 236 ± 124 days of follow-up) compared with 60% (n = 6/10) of patients undergoing initial PTA (at 62.5 ± 44 days of follow-up). Primary patency rates (Kaplan-Meier) after primary stent placement were 92%, 85%, and 69% at 1, 3, and 6 months, respectively, compared with 70%, 60%, and 50% after PTA (P = .17). Primary-assisted patency for the entire cohort was 97% at 6 and 12 months. Major complications were one arterial rupture managed endovascularly and one artery dissection that precipitated HAT and required retransplantation. The overall rate of HAT in the entire cohort was 4.3% (1/23).

CONCLUSIONS

Endovascular treatment of HAS can be performed with high technical success, excellent primary-assisted patency, and acceptable morbidity. Initial use of a stent may improve primary patency when compared with PTA. The need for reintervention is common, placing particular importance on aggressive surveillance. Longer follow-up and a larger cohort are needed to confirm these encouraging early results.

Hepatic artery kinking during liver transplantation: survey and prospective intraoperative flow measurement

BACKGROUND

Hepatic artery thrombosis (HAT) represents the most common vascular complication occurring after liver transplantation (LT). Herein, we report the results of a prospective study of hepatic artery flow (HAF) measurement during abdominal wall closure after LT along with the results of an international survey of procedures adopted, in order to avoid the arterial kinking (AK) in case of long artery.

METHODS

Sixty-four surgeons were asked regarding the different procedures used to avoid AK in the presence of long artery. We prospectively assessed the HAF during three phases of LT in 26 consecutive LT performed in patients with a long HA: after completion of the biliary anastomosis (M0), and partial abdominal wall closure with (M1w) or without (M1w/o) hepatic artery anti-kinking method (HAAK).

RESULTS

Sixty (93.7 %) surgeons replied to the survey: 44 (73.3 %) surgeons cut the artery as short as possible, of whom 38 (86.3 %) interposed an oxidized polymer or the omentum, and six (13.7 %) used other systems. Fourteen (23.3 %) surgeons did not use any interposition methods. The remaining two (3.3 %) surgeons left a long artery without HAAK. In our cohort we obtained the following HAF measures: M0 152 mL/min (89-205), M1 without HAAK 114 (66-168) and M1 with HAAK procedure 158 (91-219) (p = 0.002).

CONCLUSIONS

Our survey confirms that no consensus is currently available regarding the most effective method for avoiding AK. Kinking occurs most probably when the liver is released in its final position. The utilization of an interposition method could ensure the maintenance of a correct HAF.

Pediatric intestinal transplantation: normal radiographic appearance and complications

We present a pictorial essay on pediatric intestinal transplantation that describes the indications for pediatric intestinal transplantation, surgical technique, and the role of imaging in the pre-transplant work-up and detection of post-transplant complications. We illustrate the normal post-transplant imaging appearance and common complications, including rejection, infection, post-transplant lymphoproliferative disease (PTLD), mechanical dysfunction and vascular complications. We conclude with an imaging algorithm for suspected post-transplant complications based on clinical scenarios.

Liver transplantation and spontaneous neovascularization after arterial thrombosis: "the neovascularized liver"

The only arterial pathway available after liver transplantation is the hepatic artery. Therefore, hepatic artery thrombosis can result in graft loss necessitating re-transplantation. Herein, we present evidence of neovascularization at long-term follow-up in a series of transplant patients with hepatic artery thrombosis. We termed this phenomenon "neovascularized liver". Hepatic artery thrombosis was noted in 30/407 cases (7.37%), and occurred early in 13 patients (43.3%) and late (>30 days) in 17 (56.7%) patients. At the time of this study, 11 (36.7%) patients had a neovascularized liver. Those patients with neovascularized liver and normal liver function were closely followed. Of these patients, 10 (91%) showed evidence of neovascularized liver by imaging, and an echo-Doppler arterial signal was recorded in all patients. The mean interval between the diagnosis of hepatic artery thrombosis and neovascularized liver was 4.1 months (range of 3-5.5 months). Liver histology showed an arterial structure in 4 (36.4%) patients. Four factors were associated with development of neovascularized liver: late hepatic artery thrombosis, early hepatic artery stenosis, site of thrombosis, and Roux-en-Y anastomosis. The overall survival rate at 54 months was 90.9%. In conclusion, a late hepatic artery thrombosis may be quite uneventful and should not automatically lead to re-transplantation.