Hepatic artery stenosis after liver transplantation: is endovascular treatment always necessary?

Safety and Effectiveness of Early Primary Stent Placement for Hepatic Artery Stenosis in Liver Transplant Recipients

PURPOSE

To evaluate the outcomes of early primary stent placement (within 30 days of liver transplantation) for hepatic artery stenosis (HAS).

MATERIALS AND METHODS

Patients who underwent liver transplantation between February 2001 and February 2024 were evaluated for HAS. Patients who underwent primary stent placement were selected and stratified based on the time from anastomosis to intervention. Early intervention was defined as primary stent placement within 30 days of surgical anastomosis. Kaplan-Meier analysis was performed for primary patency.

RESULTS

HAS occurred in 83 of 779 (11%) patients (median age, 55 years; interquartile range, 48-63 years; 27 [48%] women), with 56 patients meeting inclusion criteria. Stent placement was performed within 0-6 days of the anastomosis in 11 (20%), 7-14 days in 11 (20%), 15-30 days in 7 (12%), 31-70 days in 9 (16%), and >70 days in 18 (32%) patients. Technical success was 100%. Primary patency rates were 89%, 87%, and 87% at 1, 3, and 5 years, respectively. Primary assisted patency rates were 100% at 1, 3, and 5 years. Early interventions at 0-6 days, 7-14 days, and 15-30 days showed primary patency rates of 100%, 90%, and 86%, respectively, at 1 year (P = .58). There was no difference in primary patency between the early (<30 days) and late (>30 days) cohorts (P = .88). There was 1 Grade 4 adverse event. There were no cases of anastomotic rupture, hepatic artery dissection, or graft failure.

CONCLUSIONS

Hepatic artery stent placement within 30 days of liver transplantation is safe and technically successful with excellent long-term primary patency.

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.

Intraoperative indocyanine green fluorescence imaging to predict early hepatic arterial complications after liver transplantation

The purpose of this study was to propose an innovative intraoperative criterion in a liver transplantation setting that would judge arterial flow abnormality that may lead to early hepatic arterial occlusion, that is, thrombosis or stenosis, when left untreated and to carry out reanastomosis. After liver graft implantation, and after ensuring that there is no abnormality on the Doppler ultrasound (qualitative and quantitative assessment), we intraoperatively injected indocyanine green dye (0.01 mg/Kg), and we quantified the fluorescence signal at the graft pedicle using ImageJ software. From the obtained images of 89 adult patients transplanted in our center between September 2017 and April 2019, we constructed fluorescence intensity curves of the hepatic arterial signal and examined their relationship with the occurrence of early hepatic arterial occlusion (thrombosis or stenosis). Early hepatic arterial occlusion occurred in 7 patients (7.8%), including 3 thrombosis and 4 stenosis. Among various parameters of the flow intensity curve analyzed, the ratio of peak to plateau fluorescence intensity and the jagged wave pattern at the plateau phase were closely associated with this dreaded event. By combining the ratio of peak to plateau at 0.275 and a jagged wave, we best predicted the occurrence of early hepatic arterial occlusion and thrombosis, with sensitivity/specificity of 0.86/0.98 and 1.00/0.94, respectively. Through a simple composite parameter, the indocyanine green fluorescence imaging system is an additional and promising intraoperative modality for identifying recipients of transplant at high risk of developing early hepatic arterial occlusion. This tool could assist the surgeon in the decision to redo the anastomosis despite normal Doppler ultrasonography.

Transplant Hepatic Artery Complications

Hepatic artery complications can be divided into 2 different categories, nonocclusive and steno-occlusive disease. Steno-occlusive disease is a collective term that encompasses hepatic artery thrombosis, hepatic artery stenosis, and hepatic arterial kinks, while nonocclusive arterial disease encompasses less than 5% of complications and is a collective term used to describe arteriovenous fistulae, pseudoaneurysms, arterial rupture and nonocclusive hepatic artery hypoperfusion syndrome. This article details the angiographic techniques and definitions needed to accurately diagnose arterial transplant complications and describes the technical aspects and results of endoluminal management of these arterial complications. In addition, this article discusses the presentation, etiology and indications for treatment, including surgical management of these various complications.

Current Endovascular Management of Arterial Complications After Pediatric Liver Transplantation in a Tertiary Center

PURPOSE

Pediatric liver transplant surgery is burdened by arterial complications whose endovascular treatment is not standardized. We report the outcomes of a cohort of pediatric recipients with hepatic artery complications treated by endoluminal procedures.

MATERIALS AND METHODS

From December 2019 to December 2022, consecutive transplanted pediatric patients who underwent endovascular treatment of hepatic artery complications were reviewed. The analysis included: type of complication (occlusion, stenosis, pseudoaneurysm); onset (acute =  < 15 days, subacute = 15-90 days, late =  > 90 days); endovascular technique (angioplasty, stenting); complications and outcomes. Technical success was defined as the opacification of the hepatic artery at the final angiogram with < 50% residual stenosis and no pseudoaneurysms. Clinical success was defined by graft's and patient's survival.

RESULTS

Seventeen patients (8 males; median age 33 months, IQR 9-103) underwent 21 hepatic arteriography procedures for predominantly acute or subacute occlusions (n = 7) or stenosis (n = 11) with concurrent pseudoaneurysms (n = 4). Primary and secondary technical success was achieved in 13/18 and 3/3 procedures, respectively, with overall technical success of 76%. Angioplasty alone was successful in 5/21 procedures; stent-retriever thrombectomy was performed in one occlusion with thrombosis; stenting was required in 9/17 (53%) patients. Clinical success was obtained in 14/17 (82%) patients with hepatic artery patency after a median of 367 days (IQR 114.5-500). Clinical failure occurred in 3 permanent occlusions, with 2 deaths and 1 re-transplantation. Procedure-related complications included minor events in 3/17 (18%) patients and 1/17 (6%) death.

CONCLUSION

In liver transplanted children with hepatic artery complications, endovascular treatment may provide clinical success, with stenting often required in acute and subacute conditions.

LEVEL OF EVIDENCE

Level 4.

Simple Separate Sutures Versus Continuous Sutures on Hepatic Artery Anastomosis in Liver Transplant: A Prospective Study

OBJECTIVES

Liver transplant is the definitive treatment for liver failure of various causes. There are various operation methods, of which the conventional approach is most frequently performed. In the conventional technique, 4 anastomoses are required, and different subtleties in these techniques are known to cause different rates of complications. We assessed the outcome of a simple separate (ie, interrupted) suture technique compared with a the continuous suture technique in 194 patients.

MATERIALS AND METHODS

There were 194 patients included in this single-center, controlled study. The exclusion criteria were patients who died during the surgical procedure and patients with incomplete medical records. The data recorded were age, sex, past medical history of liver disease, tobacco use, comorbidities, and whetherthe livertransplant was for the first time or retransplant. All patients included in this study were recipients of liver transplants from deceased donors. The patients were categorized as those who received either simple sutures (n = 16) or continuous sutures (n = 178). The continuous suture operations were performed first, and the simple suture operations were performed at a later time (ie, the 2 groups were temporally separated). The results included the duration of surgery, hepatic artery thrombosis rate, hepatic artery stenosis rate, 2-year survival, and further complications.

RESULTS

No evidence of hepatic artery thrombosis or hepatic artery stenosis was observed in the study groups. The duration of surgery was equal in both groups. The 2-year mortality rate was significantly higher in the simple suture group.

CONCLUSIONS

The continuous suture method seems to be accompanied by a similar duration of operation and rate of complications compared with the simple suture process.

Long-term Clinical Outcomes and Predictive Factors for Living-donor Liver Transplant Recipients With Biliary Strictures

BACKGROUND

Biliary strictures frequently occur in living-donor liver transplant (LDLT) recipients. However, long-term clinical outcomes and their associated factors are unclear.

METHODS

We analyzed an historical cohort of 228 recipients who underwent LDLT with post-liver transplantation biliary strictures. Endoscopic retrograde cholangiography or percutaneous transhepatic biliary drainage were performed to treat biliary strictures. Patients that experienced persistent jaundice over 3 mo after the initial treatment were defined as a remission-failure group.

RESULTS

Median observation period was 8.5 y after the diagnosis of biliary stricture. The 15-y graft survival (GS) rate was 70.6%, and 15-y rate of developing portal hypertension (PH) was 26.1%. Remission failure occurred in 25.0% of study participants. In the multivariate analysis, biopsy-proven acute rejection, and portal vein/hepatic artery abnormalities were risk factors for remission failure. Development of PH, retransplantation, and death were significantly more frequent in the remission-failure group. Remission failure and PH were associated with poor GS. In multivariate analyses, hepatic artery abnormality and biloma were common significant factors that were associated with a poor GS and development of PH.

CONCLUSIONS

The insufficient blood supply reflected by hepatic artery abnormality and biloma might be the most important factor that can predict poor long-term survival in LDLT patients with biliary strictures. Future large-scale prospective studies are needed to validate our observations.

Risk factors and management of hepatic artery stenosis post liver transplantation

BACKGROUND

Hepatic Artery Stenosis (HAS) after liver transplantation (LT), if untreated, can lead to hepatic artery thrombosis (HAT) that carries significant morbidity.

AIMS

To identify risk factors associated with HAS and determine if endovascular therapy (EVT) reduces the occurrence of HAT.

METHODS

This is a retrospective cohort study of adult LT patients between 2013 and 2018. The primary outcome was development of HAT, and secondary outcomes included graft failure and mortality. Logistic regression was used to ascertain the odds ratio of developing HAS. Outcomes between intervention types were compared with Fisher's-exact test.

RESULTS

The odds of HAS doubled in DCD-donor recipients (OR=2.27; P = 0.04) and transplants requiring vascular reconstruction for donor arterial variation (OR=2.19, P = 0.046). Of the 63 identified HAS patients, 44 underwent EVT, 7 with angioplasty alone, 37 combined with stenting. HAT was not significantly different in those who underwent angioplasty with or without stenting than conservative treatment (P = 0.71). However, compared to patients without HAS, patients with HAS had higher odds of biliary stricture and decreased graft and overall patient survival (log-rank P < 0.001 & P = 0.019, respectively).

CONCLUSION

HAS is significantly higher in DCD-graft recipients. EVT was not associated with reduction in HAT progression. HAS has poor graft and overall survival.

Is it safe to expand the indications for split liver transplantation in adults? A single-centre analysis of 155 in-situ splits

INTRODUCTION

Split liver transplantation (SLT) enables two recipients to be transplanted using a single donor liver; typically, an adult and a child. Despite equivalent long-term outcomes to whole grafts in selected adults, the use of these grafts in high-risk adult recipients with high model for end-stage liver disease (MELD) scores (≥30), a poor pre-transplant clinical status (ICU or hospital-bound), acute liver failure or retransplantation remains controversial.

METHODS

We retrospectively analysed all deceased donor adult liver transplants performed between July 2002 and November 2019 at a single high-volume centre and performed a propensity score-matched analysis. A subgroup analysis was performed to assess utility of these grafts for high-risk recipients.

RESULTS

A total of 1090 adult liver transplants were performed, including 155 SLT (14%). Graft survival at 1-, 3- and 5-years were comparable between recipients of split and whole liver grafts (82%, 79% and 74% vs 86%, 81% and 77% respectively, log rank p = 0.537), as was patient survival at 1-, 3- and 5-years. Recipients of split grafts were more likely to have biliary complications and hepatic artery thrombosis, but equivalent long-term survival. Recipients with high MELD scores or a poor pre-transplant clinical status had similar patient and graft survival and complication profiles irrespective of whether they received split or whole grafts.

CONCLUSIONS

SLT is an important method for addressing donor shortages and provides comparable long-term outcomes in adult recipients despite an increase in short-term complications. SLT use in high-risk recipients should be considered to allow for sickest-first allocation policies. This article is protected by copyright. All rights reserved.

How to Handle Arterial Conduits in Liver Transplantation? Evidence From the First Multicenter Risk Analysis

OBJECTIVE

The aims of the present study were to identify independent risk factors for conduit occlusion, compare outcomes of different AC placement sites, and investigate whether postoperative platelet antiaggregation is protective.

BACKGROUND

Arterial conduits (AC) in liver transplantation (LT) offer an effective rescue option when regular arterial graft revascularization is not feasible. However, the role of the conduit placement site and postoperative antiaggregation is insufficiently answered in the literature.

STUDY DESIGN

This is an international, multicenter cohort study of adult deceased donor LT requiring AC. The study included 14 LT centers and covered the period from January 2007 to December 2016. Primary endpoint was arterial occlusion/patency. Secondary endpoints included intra- and perioperative outcomes and graft and patient survival.

RESULTS

The cohort was composed of 565 LT. Infrarenal aortic placement was performed in 77% of ACs whereas supraceliac placement in 20%. Early occlusion (≤30 days) occurred in 8% of cases. Primary patency was equivalent for supraceliac, infrarenal, and iliac conduits. Multivariate analysis identified donor age >40 years, coronary artery bypass, and no aspirin after LT as independent risk factors for early occlusion. Postoperative antiaggregation regimen differed among centers and was given in 49% of cases. Graft survival was significantly superior for patients receiving aggregation inhibitors after LT.

CONCLUSION

When AC is required for rescue graft revascularization, the conduit placement site seems to be negligible and should follow the surgeon's preference. In this high-risk group, the study supports the concept of postoperative antiaggregation in LT requiring AC.

Analysis of Hepatic Arterial Reconstruction Technique Using Surgical Loupes for Living-Donor Liver Transplantation: Results From a Single Center

BACKGROUND

The reconstruction of the hepatic artery (HA) is the most complex step in living-donor liver transplantation (LDLT) owing to the artery's smaller diameter and the increased risk for HA-related complications. In this study, we presented our HA anastomosis technique for LDLT, which employed interrupted sutures using magnifying loupes.

MATERIALS AND METHODS

Since January 2019, we retrospectively analyzed 179 LDLTs that were performed at our center. HA anastomosis was performed under a loupes magnifier (2.5 or 4.5 × ) by the same surgeon.

RESULTS

There were 65 female and 114 male recipients with a mean age of 41.6 ± 21.6 years. Of the recipients, 34 were children. HA thrombosis (HAT) was seen in 3 recipients (1.67%; 1 child and 2 adults) in this series. HAT occurred on the third, sixth, and seventh days after LDLT. HAT was successfully treated with interventional radiologic technique. All recipients are still alive with a patent HA.

CONCLUSION

The use of magnifying surgical loupes and interrupted sutures to perform HA reconstruction is safe, feasible, and yields a low rate of HAT. Also, endovascular treatment can be used safely for treatment of HAT within the first week after LDLT with a high success rate and is not associated with major complications.

Liberal Use of Interposition Grafts for Arterial Reconstruction Is Safe and Effective in Adult Split Liver Transplantation

Background.

Split liver transplantation (SLT) addresses donor shortages by providing 2 partial grafts from a single donor liver. Arterial reconstruction using an interposition graft facilitates the use of split grafts with difficult recipient anatomy. Its use, however, remains controversial because of a reported increased risk of complications.

Methods.

A retrospective review of the prospectively maintained Australian National Liver Transplantation Unit database was performed. Donor, recipient, operative, and complications data for adults receiving an SLT between July 2002 and November 2019 were extracted.

Results.

Arterial reconstruction required an interposition graft in 46 of 155 patients. Overall graft and patient survival were not significantly different between the groups with 1-, 3-, and 5-y graft survivals of 82%, 77%, and 69% for those with interposition grafts and 86%, 79%, and 77% for those without interposition grafts, respectively (P = 0.499). There were more cut liver bile leaks in the interposition graft group (26% versus 9%, P = 0.004), but otherwise, no significant differences in the rate of biliary complications (39% versus 29% P = 0.200), hepatic artery thrombosis (7% versus 10%, P = 0.545), or hepatic artery stenosis (13% versus 10%, P = 0.518).

Conclusions.

Liberal use of interposition grafts for arterial reconstruction in SLT is safe and does not result in increased complications.

Risk Factors Affecting Outcomes in Pediatric Liver Transplantation: A Real-World Single-Center Experience

Background

Despite liver transplantation (LT) being the standard treatment for pediatric end-stage liver disease, complications often persist and can adversely affect the post-transplant outcomes. This study aimed to identify the risk factors affecting the outcomes in pediatric LT patients.

Material/Methods

Data from pediatric patients who underwent primary LT from March 1988 to December 2018 were retrospectively analyzed. Chronic liver disease was defined as an explanted liver showing fibrosis regardless of grade, cirrhosis, or any other underlying disease that may cause progressive liver injury leading to fibrosis or cirrhosis.

Results

A total of 255 pediatric patients underwent LT during the study period. Their 1-, 5-, and 10-year overall survival rates were 90.5%, 88.4%, and 87.8%, respectively. According to multivariate analysis, while liver disease without underlying chronic liver disease (P=0.024) and a pediatric end-stage liver disease (PELD) score ≥30 (P=0.036) were the only factors associated with worse survival, body weight <6 kg (P=0.050), whole-liver DDLT compared to LDLT (P=0.001), fulminant liver failure (P=0.008), and postoperative hepatic artery complications (P<0.001) were associated with worse graft survival. Liver disease without underlying chronic liver disease was the only factor independently associated with hepatic artery complications (P=0.003).

Conclusions

Greater caution is recommended in pediatric patients with liver disease unaccompanied by underlying chronic liver disease, high PELD score, or low body weight to improve survival after LT. Hepatic artery complication was the only surgical complication affecting the graft survival outcome, especially in patients having liver disease without underlying chronic liver disease.

Diagnostic accuracy of Doppler ultrasound for detecting hepatic artery stenosis after liver transplantation

AIM

To evaluate the diagnostic accuracy of Doppler ultrasound (DUS) in detecting hepatic artery stenosis (HAS) after liver transplantation using computed tomography angiography (CTA) as the reference standard.

MATERIALS AND METHODS

This study included data from January 2005 to November 2017, where DUS of the hepatic artery of living and deceased donor liver grafts were compared with the reference standard, CTA. DUS parameters, such as intrahepatic artery (IHA) peak systolic velocity (PSV), resistive index (RI), systolic acceleration time (SAT); and extrahepatic artery (EHA) PSV were taken. The optimum cut-off was estimated using area under the receiver operating characteristic curve (AUC). Multivariable logistic regression analysis was developed to predict HAS.

RESULTS

Ninety-nine liver transplant cases were retrieved, 50 met the inclusion criteria where nine patients had significant HAS. HAS patients had a significantly low IHAPSV with a cut-off of 35.1 cm/s (sensitivity 53.8%, specificity 78.4%, AUC 0.701). IHARI had a significantly low RI with a cut-off 0.585 (sensitivity 86.7%, specificity 85.4%, AUC 0.913). The IHASAT cut-off was 0.045 seconds (sensitivity 80%, specificity 91.4%, AUC 0.857). The EHAPSV cut-off was 197.4 cm/s (sensitivity 50%, specificity 99.1%, AUC 0.648). The prediction model using DUS parameters IHARI and IHASAT demonstrated good discrimination with an AUC of 0.930 (95% CI: 0.843, 1.000; sensitivity 93.3%, specificity 88%).

CONCLUSION

A prediction model using the DUS parameters IHARI and IHASAT showed good diagnostic accuracy of 88.6% for monitoring liver transplant patients. If validated externally, this DUS model could be utilised to diagnose HAS in liver transplant recipients.

Treatment of Hepatic Artery Stenosis in Liver Transplant Patients Using Drug-Eluting versus Bare-Metal Stents

Hepatic artery stenosis after liver transplant is often treated with endovascular stent placement. Our institution has adopted use of drug-eluting stents, particularly in small-caliber arteries. We aimed to compare patency rates of drug-eluting stents vs. traditional bare-metal stents. This was a single-institution, retrospective study of liver transplant hepatic artery stenosis treated with stents. Primary patency was defined as time from stent placement to resistive index on Doppler ultrasonography (<0.5), hepatic artery thrombosis, or any intervention including surgery. Fifty-two patients were treated with stents (31 men; mean age, 57 years): 15, drug-eluting stents; 37, bare-metal stents. Mean arterial diameters were 4.1 mm and 5.1 mm, respectively. Technical success was 100% (52/52). At 6 months, 1, 2, and 3 years, primary patency for drug-eluting stents was 80%, 71%, 71%, and 71%; bare-metal stents: 76%, 65%, 53%, and 46% (p = 0.41). Primary patency for small-caliber arteries (3.5–4.5 mm) with drug-eluting stents was 93%, 75%, 75%, and 75%; bare-metal stents: 60%, 60%, 50%, and 38% (p = 0.19). Overall survival was 100%, 100%, 94%, and 91%. Graft survival was 100%, 98%, 96%, and 90%. Stenting for hepatic artery stenosis was safe and effective. While not statistically significant, patency improved with drug-eluting stents compared with bare-metal stents, especially in arteries < 4.5 mm in diameter. Drug-eluting stents can be considered for liver transplant hepatic artery stenosis, particularly in small-caliber arteries.

Biliary Strictures Are Associated With Both Early and Late Hepatic Artery Stenosis

Background.

Hepatic artery stenosis (HAS) following liver transplantation results in hypoperfusion and ischemic damage to the biliary tree. This study aimed to investigate how vascular intervention, liver function test derangement, and time point of HAS onset influence biliary complications.

Methods.

A single-center retrospective study of adult patients that underwent primary liver transplantation. Patients were grouped according to the presence or absence of HAS and then into early (≤90 d) or late (>90 d) subgroups. Biliary complications comprised anastomotic (AS) or non ASs (NASs).

Results.

Computed tomography angiography confirmed HAS was present in 39 of 1232 patients (3.2%). This occurred at ≤90 and >90 days in 20 (1.6%) and 19 (1.5%), respectively. The incidence of biliary strictures (BSs) in the group with HAS was higher than the group without (13/39; 33% versus 85/1193; 7.1%, P = 0.01). BS occurred in 8/20 (40.0%) and 5/19 (26.3%) of the early and late groups, respectively. The need for biliary intervention increased if any liver function test result was ≥3× upper limit of normal (P = 0.019).

Conclusions.

BS occurs at a significantly higher rate in the presence of HAS. Onset of HAS at ≤90 or ≥90 days can both be associated with morbidity. Significant liver function test derangement at HAS diagnosis indicates a higher likelihood of biliary intervention for strictures.

Diagnosis and management of hepatic artery in-stent restenosis after liver transplantation by optical coherence tomography: A case report

BACKGROUND

Percutaneous transluminal angioplasty and stenting represent an effective treatment for hepatic artery stenosis after liver transplantation. In the first year after stenting, approximately 22% of patients experience in-stent restenosis, increasing the risk of artery thrombosis and related complications, and 50% experience liver failure. Although angiography is an important tool for diagnosis and the planning of therapeutic interventions, it may raise doubts, especially in small-diameter arteries, and it provides low resolution rates compared with newer intravascular imaging methods, such as optical coherence tomography (OCT).

CASE SUMMARY

A 64-year-old male developed hepatic artery stenosis one year after orthotropic liver transplantation and was successfully treated with percutaneous transluminal angioplasty with stenting. Five months later, the Doppler ultrasound results indicated restenosis. Visceral arteriography confirmed hepatic artery tortuosity but was doubtful for significant in-stent restenosis (ISR) and intrahepatic flow reduction. To confirm ISR, identify the etiology and guide treatment, OCT was performed. OCT showed severe stenosis due to four mechanisms: Focal and partial stent fracture, late stent malapposition, in-stent neointimal hyperplasia, and neoatherosclerosis.

CONCLUSION

Intravascular diagnostic methods can be useful in evaluating cases in which initial angiography results are not sufficient to provide a proper diagnosis of significant stenosis, especially with regard to ISR. A wide range of diagnoses are provided by OCT, resulting in different treatment options. Interventional radiologists should consider intravascular diagnostic methods as additional tools for evaluating patients when visceral angiography results are unclear.

Splenic Artery Transposition for Arterial Reconstruction in Living Donor Liver Transplantation

PURPOSE

In living donor liver transplantation, poor compatibility of the recipient hepatic artery remains a technical challenge. Here, we analyzed our 14 years of experience with extra-anatomic hepatic artery reconstruction.

METHODS

Between July 2004 and December 2018, there were 1063 liver transplantations at our center. All patients with an extra-anatomic hepatic artery reconstruction were identified. The gastroduodenal artery and the transposed splenic artery were the primary options for extra-anatomic arterial reconstruction. Patient characteristics, operative data, and post-transplant outcome were reviewed retrospectively.

RESULTS

There were 22 patients with extra-anatomic hepatic artery reconstruction, 6 with gastroduodenal artery, and 16 with splenic artery. There were 2 major complications: 1 patient underwent early reoperation due to bleeding from the splenic artery trunk and another had an iatrogenic injury to the transposed splenic artery during conversion hepaticojejunostomy. Both were treated successfully with surgery. One patient died perioperatively due to sepsis. The 1- and 3-year graft survival rates of these 16 patients were 93.7% and 87.5%.

CONCLUSION

If the hepatic arteries are not suitable for anastomosis, then we consider the gastroduodenal artery and the splenic artery to be the conduits of choice for extra-anatomic arterial reconstruction. The transposed splenic artery is very consistent, easily accessible, and offers adequate length and diameter for successful arterial anastomosis.

Endovascular Therapy of Arterial Complications Within the First Week After Liver Transplant

BACKGROUND

Recent radiologic advances have made endovascular treatment a very successful option for arterial complications after liver transplant. This article presents our experience of using endovascular treatments during the first week after liver transplant.

METHODS

This study is a retrospective, single-center analysis. Liver transplants performed between 2010 and 2018 were analyzed. All patients underwent Doppler ultrasonography on days 1 and 7. Endovascular therapy was indicated in hepatic artery thrombosis diagnosed early after transplant and in stenosis when hepatic narrowing was > 70%. Patients were treated with subcutaneous anticoagulant therapy and with antiplatelet agents after endovascular therapy.

RESULTS

Seven patients (1.1%) were included in the study. Stenosis was the reason in 5 patients while 2 patients had symptoms of thrombosis. The first 2 patients were initially treated with angioplasty; both had restenosis and were treated with angioplasty and stent placement, respectively. The 5 most recent patients received stenting as a primary treatment. Two of these patients developed a new stenosis. No patient developed any hepatic artery complication related to the procedure, and only 1 patient experienced a postprocedure complication (femoral artery pseudoaneurysm), which was managed conservatively. No patient required retransplant. After a median follow-up of 48 months (range, 35-85 months) 1 patient had died, and the rest were alive and asymptomatic.

CONCLUSIONS

Although there is scant experience of the use of endovascular therapy very shortly after liver transplant, recent advances in interventional radiology have made the technique feasible and safe, and it achieves a high success rate.

Transplant Hepatic Artery Stenosis: Endovascular Treatment and Complications

Hepatic artery stenosis (HAS) is an infrequent complication of liver transplant; if left untreated, it can lead to hepatic artery thrombosis with high risk of biliary necrosis and graft loss. HAS is diagnosed with screening Doppler ultrasound, together with computed tomography angiography and magnetic resonance angiography. Endovascular treatment with angioplasty ± stent placement is safe and effective with infrequent major complications; however, when complications occur, they can devastate long-term graft survival. Herein, we present two cases of HAS treated with balloon angioplasty with resultant major complications requiring operative intervention.

Primary Stent Placement for Hepatic Artery Stenosis After Liver Transplantation: Improving Primary Patency and Reintervention Rates

Recent studies have reported high rates of reintervention after primary stenting for hepatic artery stenosis (HAS) due to the loss of primary patency. The aims of this study were to evaluate the outcomes of primary stenting after HAS in a large cohort with longterm follow-up. After institutional review board approval, all patients undergoing liver transplantation between 2003 and 2017 at a single institution were evaluated for occurrence of hepatic artery complications. HAS occurred in 37/454 (8%) of patients. HAS was defined as >50% stenosis on computed tomography or digital subtraction angiography. Hepatic arterial patency and graft survival were evaluated at annual intervals. Primary patency was defined as the time from revascularization to imaging evidence of new HAS or reaching a censored event (retransplantation, death, loss to follow-up, or end of study period). Primary stenting was attempted in 30 patients (17 female, 57%; median age, 51 years; range, 24-68 years). Surgical repair of HAS prior to stenting was attempted in 5/30 (17%) patients. Endovascular treatment was performed within 1 week of the primary anastomosis in 5/30 (17%) of patients. Technical success was accomplished in 97% (29/30) of patients. Primary patency was 90% at 1 year and remained unchanged throughout the remaining follow-up period (median, 41 months; interquartile range [IQR], 25-86 months). Reintervention was required in 3 patients to maintain stent patency. The median time period between primary stenting and retreatment was 5.9 months (IQR, 4.4-11.1 months). There were no major complications, and no patient developed hepatic arterial thrombosis or required listing for retransplantation or retransplantation during the follow-up period. In conclusion, primary stenting for HAS has excellent longterm primary patency and low reintervention rates.

Acute allograft rejection in liver transplant recipients: Incidence, risk factors, treatment success, and impact on graft failure

Objective This study was performed to identify risk factors for acute cellular rejection after liver transplantation (LT). Methods Consecutive LT recipients who underwent surgery in our institution from 2002 to 2015 were retrospectively evaluated. Results In total, 176 patients were eligible for statistical analysis. During a mean observation period of 61.1 ± 36.3 months, 43 episodes of acute rejection were evident. Of these, 34 (79.0%) were responsive to methylprednisolone, 3 (7.0%) were treated by adjusting the dosage of immunosuppressive agents, and 6 (14.0%) were methylprednisolone-resistant and treated using anti-thymocyte globulin. Biliary complications (odds ratio [OR] = 4.89, 95% confidence interval [CI] = 2.00-11.98); donor-negative, recipient-positive CMV mismatch (OR = 9.88, 95% CI = 1.18-82.36); sex mismatch (OR = 3.16, 95% CI = 1.31-8.10); and sex mismatch with a female donor (OR = 3.00, 95% CI = 1.10-7.58) were identified as significant risk factors for acute graft rejection after LT. Conclusion In patients who develop acute cellular rejection after LT, biliary complications should be evaluated as a potential cause. Most acute rejections after LT respond to bolus corticosteroid therapy.

The rate of hepatic artery complications is higher in pediatric liver transplant recipients with metabolic liver diseases than with biliary atresia

BACKGROUND

Liver transplantation (LT) is an excellent treatment option for patients with biliary atresia (BA) who fail portoenterostomy surgery. LT is also increasingly performed in patients with metabolic liver diseases. This study compared the outcomes in pediatric patients who underwent LT for metabolic liver diseases and BA.

BASIC PROCEDURES

Data from 237 pediatric patients who underwent primary LT at Seoul National University Hospital from 1988 to 2015, including 33 with metabolic liver diseases and 135 with BA, were retrospectively analyzed.

MAIN FINDINGS

Compared with children with BA, children with metabolic liver diseases were significantly older at the time of LT (121.3 vs. 37.3 months; P < 0.001), and had lower Child-Pugh (7.1 vs. 8.4; P = 0.010) and Pediatric End-stage Liver Disease (6.5 vs. 12.8; P = 0.042) scores. Overall survival rates were similar (87.8% vs. 90.8%; P = 0.402), but hepatic artery (HA) complications were significantly more frequent in children with metabolic liver diseases (12.1% vs. 1.5%; P = 0.014).

PRINCIPAL CONCLUSION

Despite similar overall survival, children with metabolic liver diseases had a higher rate of HA complications.

TYPE OF SUBMISSION

Original article, Case control study, Retrospective.

EVIDENCE LEVEL

III.

Interventional radiology in the management of the liver transplant patient

Liver transplantation (LT) is commonly used to treat patients with end-stage liver disease. The evolution of surgical techniques, endovascular methods, and medical care has led to a progressive decrease in posttransplant morbidity and mortality. Despite these improvements, a multidisciplinary approach to each patient remains essential as the early diagnosis and treatment of the complications of transplantation influence graft and patient survival. The critical role of interventional radiology in the collaborative approach to the care of the LT patient will be reviewed. Liver Transplantation 23 1328-1341 2017 AASLD.

Refractory anastomotic bile leaks after orthotopic liver transplantation are associated with hepatic artery disease

BACKGROUND AND AIMS

Anastomotic bile leaks are common after orthotopic liver transplant (OLT), and standard treatment consists of placement of a biliary endoprosthesis. The objectives of this study were to identify risk factors for refractory anastomotic bile leaks and to determine the morbidity associated with refractory bile leaks after OLT.

METHODS

Consecutive adult patients who underwent ERCP for treatment of post-OLT biliary adverse events between 2009 and 2014 at a high-volume transplant center were retrospectively identified. A refractory leak was defined as a bile leak that persisted after placement of a plastic biliary endoprosthesis and required repeat endoscopic or surgical intervention.

RESULTS

Forty-three subjects met study inclusion criteria. Median age was 57 years, and 36 (84%) subjects were men. Refractory bile leaks were diagnosed in 40% of subjects (17/43). Time-to-event analysis revealed an association between refractory bile leaks and the combined outcome of death, repeat transplant, or surgical biliary revision (hazard ratio, 3.78; 95% confidence interval, 1.25-11.45; P = .01). Hepatic artery disease was more common with refractory compared with treatment-responsive bile leaks (53% vs 8%, P = .001).

CONCLUSIONS

Refractory anastomotic bile leaks after liver transplantation are associated with decreased event-free survival. Hepatic artery disease is associated with refractory leaks. Large-scale prospective studies should be performed to define the optimal management of patients at risk for refractory bile leaks.

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.

Rapid Resolution of Cholangitic Abscess and Biliary Sepsis in a Liver Transplant Recipient after Hepatic Artery Revascularization

Hepatic arterial flow is paramount in preserving biliary integrity. We present an interesting clinical scenario of a liver transplant recipient with biliary anastomotic stricture who developed biliary abscess and sepsis after Endoscopic Retrograde Cholangiopancreatography. The abscess did not respond to maximal medical management, percutaneous drainage, and adequate endoscopic biliary drainage. Clinically, patient continued to deteriorate and imaging identified hepatic artery stenosis which was treated with percutaneous intra-arterial stenting. Revascularization and perfusion of infected area led to rapid resolution of abscess and sepsis. This case emphasizes the anatomic basis of biliary ductal pathology. An important educational point is to understand that interrupted hepatic arterial supply can lead to biliary complications in liver transplant recipients and early correction of perfusion deficit should be pursued in such cases. In nonresolving hepatobiliary infections after liver transplantation, hepatic arterial compromise should be looked for and if present promptly treated. Reperfusion of biliary system in our patient led to improved antibiotics penetration, resolution of abscess and sepsis, and healing of biliary stricture.

Evaluation of hepatic vascular endothelial injury during liver storage by molecular detection and targeted contrast-enhanced ultrasound imaging

We hypothesized that lack of the high-energy phosphates during liver storage may potentially cause persistent injury to the vascular endothelium. Biopsies were obtained from livers obtained from beating heart human donors, stored either in the standard storage solution, that is, University of Wisconsin solution (UWS) or Celsior, and examined for various markers related to progressive endothelial injury. The expression of P2Y1 receptor, the major signal transduction machinery for adenosine triphosphate/adenosine diphosphate, decreased in hepatic vascular endothelial cells over time. Despite unaltered endothelial nitric oxide synthase (eNOS) levels, serine1177-phosphorylated eNOS, the active form of eNOS, progressively decreased with time. The production of nitric oxide enzyme decreased with time when liver tissues were examined in vitro. This also coincided with decreased interaction of eNOS with actin nucleating proteins like myristoylated alanine-rich C kinase substrate and Rac1, which plays a role in modulating the cytoskeleton and helps position eNOS in a favorable cytosolic position for active enzymatic activity. Conversely, the interaction of eNOS with caveolin1 was significantly increased 6 H after ex vivo storage. Finally, we demonstrated by targeted contrast-enhanced ultrasound that membrane-bound vascular cell adhesion molecule-1 in the hepatic vascular endothelial cell increased after 6 H of ex vivo storage. Overall, the results of this study provide evidence of a progressive hepatic vascular endothelial injury during the ex vivo storage. This may be a causative factor for ischemic cholangiopathy and delayed graft function post liver transplantation. © 2015 IUBMB Life, 68(1):51-57, 2015.