The use of percutaneous transluminal angioplasty in hepatic artery stenosis after transplantation

Endovascular therapies for hepatic artery stenosis post liver transplantation

PURPOSE

To evaluate primary patency at 12 months after endovascular therapies in hepatic artery stenosis.

METHODS

A retrospective review of all endovascular interventions for hepatic artery stenosis (HAS) after liver transplantation that occurred between June 2013 and November 2020 was performed at a single institution in France. Follow up occurred from 1 month to 4 years (median 15 months). The treatment consisted of dilation with a balloon or stent. We analyzed short-term (technical success and complications) and long-term outcomes (liver function, arterial patency, graft survival at 12 months (GS), and reintervention). We also compared percutaneous balloon angioplasty (PBA) with stent placement. PBA alone was used if < 30% residual stenosis of the hepatic artery was achieved. Stenting was performed if there was greater than 30% residual stenosis and in the case of complications (dissection or rupture).

RESULTS

A total of 18 stenoses were suspected on the basis of routine surveillance duplex ultrasound imaging (peak systolic velocity > 200 cm/s, systolic accelerating time > 10 ms and resistive index < 0.5), all of which were confirmed by angio CT, but only 17 were confirmed by angiography. Seventeen patients were included (14 males, mean age 57 years; and three females, mean age 58 years). Interventions were performed in 17 cases (95%) with PBA only (5/17), stent only (5/17) or both (4/17). Immediate technical success was 100%. Major complications occurred in 1 of 17 cases (5.8%), consisting of target vessel dissection. The analysis of the three (groups PBA only, stent only or both) showed the same procedural success (100%), GS (100%) and normal liver function after the procedures but different rates of complications (20% vs. 0% vs. 0%), arterial patency at 12 months (60% vs. 80% vs. 85%) (p = 0.4), early stenosis (40% vs. 80% vs. 0%) or late stenosis (60% vs. 20% vs. 100%) and requirement for reintervention (40% vs. 20% vs. 14%) (p = 0.56).

CONCLUSION

This study suggests that PBA, stent, or both procedures show the same primary patency at 12 months. It is probably not a definitive answer, but these treatments are safe and effective for extending graft survival in the context of graft shortages.

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.

Catheter Thrombolysis of Thrombosed Hepatic Arteries in Liver Transplant Recipients: Predictors of Success and Role of Thrombolysis

Hepatic artery thrombosis is an uncommon complication of liver transplantation. However, it is a major indication for re-transplantation. The use of transcatheter thrombolysis and subsequent surgical revascularization as a graft salvage procedure is discussed. Four of 5 cases (80%) were successful in re-establishing flow and uncovering underlying arterial anatomic defects. None were treated definitively by endoluminal measures due to an inability to resolve the underlying anatomic defects. However, 2 of 5 cases (40%) went on to a successful surgical revascularization and represent successful long-term outcome of transcatheter thrombolysis followed by definitive surgical revascularization. We conclude that, definitive endoluminal success cannot be achieved without resolving associated, and possibly instigating, underlying arterial anatomical defects. However, reestablishing flow to the graft can unmask underlying lesions as well as asses surrounding vasculature thus providing anatomical information for a more elective, better planned and definitive surgical revision.

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.

Simultaneous surgical repair for combined biliary and arterial stenoses after liver transplantation

After orthotopic liver transplantation (OLT), hepatic artery stenoses (HAS) and biliary strictures (BS) are frequent. These complications remain a significant cause of graft loss and patient death. The present study reported a group of 7 patients in whom both HAS and BS were identified and treated surgically in the same surgical session. The median times to diagnosis were 42 (range, 5-120) and 84 (range, 15-280) days after OLT for biliary and arterial stenosis, respectively. The mortality was nil. Two patients (28%) developed postoperative complications. The median hospital stay was 16 days (range, 10-42). All patients are alive; there was no graft loss. With a median of 76 months' follow-up (range, 38-132), only 1 patient (14%) developed recurrence of both BS and HAS. In patients with coincident biliary and artery stenosis, concomitant surgical repair is feasible, offering good long-term results.

Hepatic arterial stenosis assessed with doppler US after liver transplantation: frequent false-positive diagnoses with tardus parvus waveform and value of adding optimal peak systolic velocity cutoff

PURPOSE

To evaluate the utility of the tardus parvus waveform of the hepatic artery at Doppler ultrasonography (US) in the diagnosis of hepatic arterial stenosis in liver transplant (LT) recipients and determine whether the accuracy of such a diagnosis is enhanced by including an optimal peak systolic velocity (PSV) cutoff.

MATERIALS AND METHODS

This retrospective study was institutional review board approved; the requirement for informed consent was waived. The authors identified 361 LT recipients (267 male, 94 female) who underwent Doppler US and either computed tomography (CT) or angiography, with an interval between these examinations of less than 1 week. At Doppler US, tardus parvus pattern was defined as a waveform with a resistive index (RI) of less than 0.5 and a systolic acceleration time longer than 0.08 second. At CT or angiography, patients were assigned to the hepatic arterial stenosis (≥50% vessel narrowing) or nonstenosis group. The capability of the tardus parvus pattern to facilitate the diagnosis of hepatic arterial stenosis was calculated. The difference in PSV between the true- and false-positive tardus parvus patterns was evaluated. Receiver operating characteristic (ROC) analysis was performed to determine the optimal cutoff PSV for diagnosing hepatic arterial stenosis. The capability of the tardus parvus pattern and an optimal PSV cutoff in the diagnosis of hepatic arterial stenosis was determined.

RESULTS

Sixty transplant recipients had the tardus parvus pattern at Doppler US. The sensitivity, specificity, and positive predictive value (PPV) of the tardus parvus pattern were 72% (23 of 32 LT recipients), 88.8% (292 of 329 LT recipients), and 38% (23 of 60 LT recipients), respectively. The false-positive rate was 11.2% (37 of 329 LT recipients). ROC analysis revealed an optimal PSV cutoff of less than or equal to 48 cm/sec for diagnosing hepatic arterial stenosis. The combination of the tardus parvus pattern and a PSV cutoff of less than or equal to 48 cm/sec improved specificity to 99.1% (326 of 329 LT recipients) and the PPV to 88% (22 of 25 LT recipients), thereby reducing the false-positive rate to 1% (three of 329 LT recipients) while slightly decreasing the sensitivity to 69% (22 of 32 LT recipients).

CONCLUSION

Use of the tardus parvus waveform of the hepatic artery resulted in a low PPV and a high false-positive rate. However, the combination of the tardus parvus pattern and an optimal PSV cutoff greatly improved the PPV and reduced the false-positive rate in the diagnosis of hepatic arterial stenosis.

Association of hepatic artery stenosis and biliary strictures in liver transplant recipients

Biliary complications are important causes of morbidity and graft failure in patients after orthotopic liver transplantation. Nonanastomotic biliary strictures (NAS) are frequently the most challenging biliary complications. Hepatic artery stenosis (HAS) as a cause of biliary strictures has not been studied well systematically. We performed a retrospective cohort study of patients who underwent liver transplantation at our institution between 1995 and 2007 to determine the incidence of biliary strictures (nonanastomotic and anastomotic) with HAS. Forty patients were identified, and they were compared with 62 matched non-HAS controls. Overall, NAS and biliary anastomotic strictures were seen more frequently in patients with HAS (24/40 or 60%) versus control patients (6/62 or 9.67%, P < 0.000001). Cholangiographic evidence of NAS was seen in 10 of 40 study patients (25%) and in 1 of 62 control patients (2%, P < 0.0001), whereas evidence of biliary anastomotic strictures was seen in 14 of 40 study patients (35%) and in 5 of 62 control patients (8%, P = 0.0006). The cold ischemia time was also found to be associated with the presence of NAS in patients with HAS (P = 0.024). Patients with biliary strictures were generally managed successfully with endoscopic retrograde cholangiopancreatography balloon dilation/stenting, except for 4 NAS patients who had significant morbidity and mortality. In conclusion, the development of HAS, particularly with a prolonged cold ischemia time, may increase the NAS risk after liver transplantation. HAS is also associated with the development of biliary anastomotic strictures. Prospective studies of frequent arterial monitoring for the early detection of HAS and interventions to prevent biliary complications are needed.

Endovascular therapy for hepatic artery stenosis and thrombosis following liver transplantation

PURPOSE

To evaluate the effectiveness of endovascular management of steno-oclusive disease in liver transplants.

METHODS

Retrospective review of liver transplant recipients with hepatic artery stenosis (HAS) or thrombosis (HAT) was performed. The HAS group was treated with balloon angioplasty with selective stent placement. The HAT group was treated with catheter-directed thrombolysis. Primary, unassisted, and assisted patency and graft survival rates were calculated.

RESULTS

In all, 31 patients were identified (21 males; mean age, 51 years). A total of 25 of 31 (81%) patients had HAS and 6 of 31 (19%) had HAT. Collectively, a total of 35 endovascular procedures were performed to treat HAS in 25 patients. Overall technical success rate was 91%, with 11% major complication rate. Primary-assisted patency rate and graft survival at 6 and 12 months were 87% and 81%, and 76% and 72%, respectively. Only 1 successful thrombolysis of HAT was achieved.

CONCLUSION

Endovascular management is effective for HAS but not for HAT.

Seeking beyond rejection: an update on the differential diagnosis and a practical approach to liver allograft biopsy interpretation

Pathologic evaluation of liver allograft biopsies plays an integral role in the management of patients after liver transplantation. This review summarizes the clinical context and classical histology of different types of allograft rejection and also the common entities that enter the differential diagnosis of allograft rejection, and provides practical approaches to liver allograft biopsy interpretation. In addition, some of the new developments in the field of liver transplant pathology are updated. The purpose of this review is to provide guidance for pathologists interpreting liver allograft biopsies, particularly those interested in developing expertise in the field of liver transplant pathology.

Prevalence, treatment, and outcomes of the hepatic artery stenosis after liver transplantation

INTRODUCTION

Hepatic artery stenosis (HAS) after liver transplantation can lead to altered hepatic function and/or thrombosis, there by increasing morbidity and mortality. The prevalence of HAS in the literatures varies from 4% to 11%.

OBJECTIVE

We sought to describe the prevalence and treatment of hepatic artery stenosis.

METHODS

We performed a descriptive retrospective analysis of 253 liver transplantations from March 1998 to May 2007, including patients with suspected HAS owing to increased hepatic enzymes, altered Doppler ultrasound (us) and hepatic biopsy. The confirmation of HAS was achieved through areriography.

RESULTS

Nine patients were identified to have HAS, a 3.5% prevalence. Among the HAS patients, seven were male and two female. Their average age was 35.5 years (range, 65 to 53). The average time between the diagnosis and transplantation was 14.2 months (range, 9 to 68). The increase in hepatic enzymes among this group averaged: aspartate aminotransferase 131 U/L (range, 26 to 412) and alanine aminotransferase 192 U/L (range, 35 to 511). Doppler US showed alteration in the resistance level index. All patients underwent areriography; only one could not be treated owing to severe hepatic artery spasm, which also occurred during another attempt weeks after the first one. Among the eight patients, six were treated with stents and two with angioplastis. All treated patients displayed improvements in parameters. Four patients treated with stents required retreatment: two underwent angioplasty and two, a thrombolytic. One graft rethrombosed but evolved in compensated fashion with recanalization by collaterals. There has been no graft loss or mortality in this population. The average time of posttreatment follow-up was 31.28 (range, 9 to 68) months.

CONCLUSION

The prevalence of HAS in our unit was within that reported in the literature. Treatment with a stent or angioplasty proved to be efficient to control this complication, considering that hepatic function recovered and that there was neither graft nor patient loss.

Successful arterial thrombolysis and percutaneous transluminal angioplasty for early hepatic artery thrombosis after split liver transplantation in a four-month-old baby

Early HAT is the most frequent and severe vascular complication following liver transplantation. It is one of the major causes of graft failure and mortality. Endovascular thrombolytic treatment in patients with thrombotic complications after liver transplantation is an attractive alternative to open surgery as lower morbidity and mortality rates are reported for it. PTA following transcatheter thrombolysis has been successfully used to treat HAT in adults. To the best of our knowledge, there have not been any reports of a successful transcatheter thrombolysis using interventional radiological techniques in a patient only four months old. The present report describes the successful endovascular emergency treatment of a HAT three days after DD split liver transplantation.

Hepatic artery stenosis after liver transplant, managed with percutaneous angioplasty and stent placement

Hepatic artery stenosis is a recognized vascular complication of orthotopic liver transplant that carries significant morbidity and mortality. The authors present a case of hepatic artery stenosis in a 50-year-old female successfully treated with balloon angioplasty and stent. This case report highlights the importance of percutaneous intervention as a preferred treatment option in patients with hepatic artery stenosis post-orthotopic liver transplant.

Complications of arterial reconstruction in living donor liver transplantation: a single-center experience

PURPOSE

Microsurgical reconstruction of the fine hepatic arteries (HA) reduces the chance of complications in living donor liver transplantation (LDLT). We reviewed HA reconstructions and analyzed their complications and treatment in a single center.

METHODS

Between August 1996 and September 2004, we performed LDLT on 71 adults and 19 children. Patients received a lateral segment graft (n = 16), a left lobe graft (n = 11), an extended left lobe graft (n = 12), or a right lobe graft (n = 51).

RESULTS

Hepatic artery reconstruction was performed by end-to-end anastomosis under an operating microscope in all except five adults who received right lobe grafts with loupe magnification. Arterial complications developed in 5 (5.6%) of the 90 patients. Three patients required reanastomosis during their primary operation because of HA thrombosis, anastomotic kinking, and stenosis, respectively. There were three postoperative complications: an anastomotic stenosis, revised by percutaneous transluminal angioplasty; rupture of an HA pseudoaneurysm, treated by embolization; and anastomotic kinking, revised by reanastomosis. The patient with the pseudoaneurysm died of arterial complications. Multivariate analysis of cases before (4/13, 30.8%) and after 2000 (1/77, 1.3%) revealed that surgical experience was the only significant factor in reducing the incidence of HA complications (P = 0.007).

CONCLUSION

Case number-dependent anastomotic reliability using microsurgical techniques is important for safer arterial reconstruction.

Clinical outcomes from hepatic artery stenting in liver transplantation

Hepatic artery stenosis after liver transplantation may affect liver function and result in hepatic artery thrombosis. Surgical reconstruction has been the first choice for treatment. Interventional radiologic technique can be used, but there is no report on long-term outcome. The aim of this paper is to assess current outcome and complications of hepatic artery stenting. Twenty-six adult patients were stented for hepatic artery stenosis between 1998 and 2003. Nine patients had previous surgical reconstruction for hepatic artery stenosis. Seventeen patients suffered newly developed hepatic artery stenosis. Three patients were retransplanted. After stenting, the patients were followed by Doppler ultrasound at day 1, 1 month, and 6 months. Angiography was scheduled in 6 months. Four patients died within 2 months. The other 22 patients were followed for mean 31 +/- 14 months (8-71 months). One of 22 patients died from renal failure 2 years later. Twelve patients' hepatic arteries looked normal after stenting. Restenosis was seen in 8 patients (36%). Other complications were artery thrombosis (n = 1) and long segment stricture (n = 1). In 2 patients (25%) restenosis resulted in thrombosis. Six of the 8 patients who developed recurrent stenosis were successfully treated interventionally: restent (n = 5) and balloon dilation (n = 3). However, 3 patients (38%) restenosed. Kaplan-Meier complication-free survival was 54% at 1 year after stenting. In conclusion, hepatic artery stenting is a viable treatment for hepatic artery stenosis with reasonable results. Stenting is useful as adjuvant treatment after surgical revision.

Percutaneous transluminal angioplasty for hepatic artery stenosis after living donor liver transplantation

The purpose of this study was to evaluate the efficacy of percutaneous transluminal angioplasty (PTA) for treatment of hepatic artery stenosis after living donor liver transplantation. Eighteen patients with hepatic artery stenosis after living donor liver transplantation were included in this study. The success rate and complications of PTA and recurrent stenosis of the hepatic artery were evaluated. Seventeen of 18 patients (94.4%) were successfully treated without complication by a first PTA procedure. Recurrence of hepatic artery stenosis occurred in 6 patients (33.3%). Repeated PTA was performed 12 times for the 6 patients. Two complications occurred as arterial dissection and perforation. As a consequence, the complication rate was 6.7%, involving 2 of 30 procedures in total. In conclusion, PTA is effective for treatment of hepatic artery stenosis after living donor liver transplantation without an increase in the complication rate.

Hepatic artery stenosis in liver transplant recipients: primary treatment with percutaneous transluminal angioplasty

PURPOSE

To evaluate the efficacy of hepatic artery percutaneous transluminal angioplasty (PTA) in the treatment of hepatic artery stenosis (HAS).

MATERIALS AND METHODS

A retrospective analysis was performed of all cases of HAS documented by angiography from January 1995 to June 2003 at the authors' institution. Management was evaluated and long-term patency was documented by Doppler ultrasonography. The patency, restenosis, and hepatic artery thrombosis (HAT) rates were determined by the Kaplan-Meier method. The technical success of hepatic artery PTA was stratified according to the location of the stenoses relative to the anastomosis, as well as by the presence of associated hepatic arterial kinks.

RESULTS

Thrombosis was seen in 65% +/- 13% of untreated HAS cases within 6 months. Stenotic lesions without associated arterial kinks had an improved technical success rate and a reduced complication rate of 94% and 10%, respectively, compared with lesions with associated hepatic arterial kinks treated with hepatic artery PTA (14% and 29%, respectively). The 1-year primary and primary assisted patency rates of hepatic artery PTA for all lesions were 44% +/- 12% and 60% +/- 11%, respectively, and were 65% +/- 10% and 80% +/- 8%, respectively, for lesions not associated with hepatic arterial kinks. The 1-year HAT rate and restenosis rate after hepatic artery PTA were 19% +/- 10% and 32% +/- 11%, respectively. The 1-year primary assisted patency rate for hepatic artery PTA with repeat PTA performed for restenosed lesions and surgical revascularization performed for failed PTA was 74% +/- 10%.

CONCLUSIONS

Untreated HAS carries a high morbidity rate. Hepatic artery PTA can play a large role in the management of HAS by reducing the HAT rate more than threefold. With appropriate lesion selection, hepatic artery PTA will have better patency rates than those associated with hepatic artery stent placement.

Transhepatic Balloon Dilation of Anastomotic Biliary Strictures in Liver Transplant Recipients: The Significance of a Patent Hepatic Artery

PURPOSE

To determine the significance of hepatic artery steno-occlusive disease on the patency of anastomotic biliary strictures in liver transplant recipients after transhepatic balloon dilation.

MATERIALS AND METHODS

A retrospective review of records of all patients undergoing transhepatic balloon dilation for anastomotic biliary strictures after orthotopic liver transplantation was performed over an 8-year period. Patency of the anastomosis was based on subsequent cholangiography. The presence of hepatic artery steno-occlusive disease was determined by Doppler ultrasound and/or angiography. The anastomotic biliary stricture patency rates were calculated by the Kaplan-Meier method.

RESULTS

Thirty-eight patients who had undergone liver transplants underwent 53 balloon dilations for anastomotic biliary strictures (nine patients for arterial disease, 26 patients had patent arteries and three patients had arteries of indeterminate patency). Eight of the 53 strictures treated (15%) were refractory to balloon dilation: 10.5% of first comers and 27% of restenotic lesions. Two of the 53 strictures treated (4%) had significant complications: hemobilia requiring blood transfusion and ductal rupture. One-year cumulative primary patency rates for anastomotic biliary strictures for patients with arterial disease, patent hepatic arteries, and all-comers were: 0%, 45% (P = .01), and 36%, respectively. One-year cumulative primary patency rates for choledocho-choledocal and choledocho-jejunal anstomoses in patients with patent arteries were 43% and 48%, respectively (P = .10).

CONCLUSIONS

In the presence of hepatic artery disease there is a lower patency of anastomotic biliary strictures after balloon dilation. Imaging of the hepatic artery should be considered to stratify patients who will have a successful outcome.

Interventional Radiology in Liver Transplantation

Radiology is a key specialty within a liver transplant program. Interventional techniques not only contribute to graft and recipient survival but also allow appropriate patient selection and ensure that recipients with severe liver decompensation, hepatocellular carcinoma or portal hypertension are transplanted with the best chance of prolonged survival. Equally inappropriate selection for these techniques may adversely affect survival. Liver transplantation is a dynamic field of innovative surgical techniques with a requirement for interventional radiology to parallel these developments. This paper reviews the current practice within a major European center for adult and pediatric transplantation.

Hepatic artery stenosis following liver transplantation: significance of the tardus parvus waveform and the role of microbubble contrast media in the detection of a focal stenosis

PURPOSE

To evaluate the role of microbubble ultrasound contrast media in detecting stenosis of the post-liver transplant extrahepatic hepatic artery (HA) in the presence of the tardus parvus spectral Doppler waveform of the intrahepatic HA.

MATERIALS AND METHODS

All post-liver transplant patients with a prolonged systolic acceleration time (SAT>0.08s) and/or a reduced resistant index (RI<0.50) of the HA (the tardus parvus waveform) on colour Doppler ultrasound (CDUS), were assessed with microbubble contrast medium for a focal arterial stenosis. Following microbubble contrast-enhanced CDUS, patients underwent arteriography or follow-up CDUS.

RESULTS

A total of 2038 examinations were performed in 529 liver transplant recipients; 16 (3.02%) tardus parvus waveforms were identified. The median SAT of the intrahepatic HA was 0.18s (range 0.11-0.38s) and the RI 0.47 (range 0.22-0.58). No extrahepatic elevated peak systolic velocity (PSV), defined as above 1.00m/s, was detected on the baseline examinations. Following the administration of microbubble contrast, medium, PSV in the extrahepatic HA was elevated in 14 of 16 patients, (median=2.15m/s, range=1.44-3.10m/s); flow was not identified in two patients. Arteriography was performed in 10 patients and confirmed stenosis in eight (median grade of stenosis 93%, range 60-99%) and occlusion in two. The measured median PSV at contrast-enhanced CDUS in the stenosis group was 2.03m/sec (range 1.44-2.71m/sec). Repeat CDUS in six patients not undergoing arteriography showed resolution in four; one underwent re-transplantation before arteriography and one patient maintains a tardus parvus waveform. In transplant recipients undergoing arteriography during the study period (n=55), no hepatic artery stenosis without a tardus parvus waveform was seen.

CONCLUSION

The tardus parvus waveform pattern is an excellent screening test for the presence of post-liver transplantation hepatic artery stenosis. There is only a limited role for microbubble ultrasound contrast agent in the presence of a tardus parvus waveform. It could be used following equivocal colour Doppler ultrasound, but arteriography will still be necessary.

Successful percutaneous transluminal angioplasty for hepatic artery stenosis in an infant undergoing living-related liver transplantation

A 1-yr-old girl underwent a living-related liver transplant, with reconstruction of hepatic artery of 2 mm in diameter under microscopy. She developed intestinal perforation requiring closure on day 4 post-transplant and suffered from hepatic artery stenosis (HAS) on post-transplant day 9. Conservative therapies, such as intravenous or transluminal administration of anti-coagulants, vasodilators or fluids, were unsuccessful and caused remarkable general edema and multiple arrhythmias as a result of increased preload. On day 15 post-transplant, because flow velocity was remarkably reduced (as shown by Doppler ultrasound) the patient underwent percutaneous transluminal angioplasty (PTA) using a kit for coronary angioplasty. The balloon catheter was inflated [first: 1.5 mm diameter, 4 atmospheric pressure (a.p.) for 30 seconds (s); second: 2.0 mm diameter, 4 a.p. for 30 s; third: 2.5 mm diameter, 10 a.p. for 30 s]. The stenosis was successfully dilated without any complication. The patient has been doing well with normal liver functions for 4 months after PTA. From this experience, PTA can be performed for HAS after liver transplantation, even in an infantile case, with a careful technique and a special device.

Stent placement in four patients with hepatic artery stenosis or thrombosis after liver transplantation

Hepatic artery stenosis and thrombosis represent dangerous complications of liver transplantation because the associated mortality and morbidity rates are high. In the past, repeat transplantation was considered the first-choice therapy; however, new surgical and interventional revascularization techniques have been suggested recently. Although extensive experience has been acquired with percutaneous transluminal angioplasty (PTA) and fibrinolysis techniques, only sporadic cases of stent placement in the hepatic artery of a transplanted liver have been reported, and no long-term results of this technique are available. In this study, seven stents (five Wallstents and two Palmaz stents) were positioned in four patients (two with stenoses and two with thromboses). Stent placement was performed in three cases after PTA and fibrinolysis, whereas primary stent placement was performed in the fourth. In all cases, technical success was achieved. During 18-25 months of follow-up, all stents proved patent and no patient required another transplantation. Although experience is still limited, the authors' experience indicates that placement of a stent in the hepatic artery in cases of stenosis or thrombosis yields good medium-term success, improving the results obtained by fibrinolysis and PTA and consequently enabling the graft to survive and avoiding the need for repeat transplantation.

Feasibility and effectiveness of using coronary stents in the treatment of hepatic artery stenoses after orthotopic liver transplantation: preliminary report

OBJECTIVE

Our aim is to evaluate the feasibility, efficacy, and patency of using coronary stents for the treatment of hepatic artery stenosis after liver transplantation.

CONCLUSION

Hepatic artery stenosis after liver transplantation can be treated using coronary stents. The low rate of complication, high technical success, and 1-year patency rates are encouraging.

Hepatic artery reconstruction in living-donor liver transplantation: a review of its techniques and complications

BACKGROUND

Hepatic arterial reconstruction is one of the most difficult procedures in living-donor liver transplantation (LDLT) because the artery used is generally small in diameter and has a short stalk. If hepatic artery thrombosis (HAT) occurs, the recipient clinical course will be unstable. The introduction of microvascular hepatic arterial reconstruction has significantly decreased the incidence of HAT.

METHODS

Fifty-two cases of LDLT were performed from October 1995 to May 2001 in our institution. Hepatic arterial reconstruction was performed under microscopic guidance.

RESULTS

HATs were recognized in 2 cases (3.8%), both of which needed reoperation.

CONCLUSIONS

Surgeons who perform hepatic arterial reconstruction in LDLT should be highly trained in microvascular techniques to decrease the incidence of HAT. This commentary reviews the surgical techniques of hepatic arterial reconstruction and possible complications that may arise in a reconstructed hepatic artery.

Dissection of an iliac artery conduit to liver allograft: treatment with an endovascular stent

Hepatic artery thrombosis remains one of the most serious complications after orthotopic liver transplantation. Sepsis, biliary leakage and strictures, and retransplantation are often the result of this devastating complication. Because retransplantation or reoperation is sometimes not possible or advisable, other means of reestablishing hepatic artery continuity are desirable. We describe a liver transplant recipient who developed a dissection of an iliac artery conduit after retransplantation that was treated with fibrinolytic therapy followed by successful placement of an endovascular stent.

Early complications after orthotopic liver transplantation

The cost and impact of early post-transplant complications continue to be high. Diagnosis and management involves a high index of suspicion, rapid diagnostic and therapeutic interventions, and elimination of technical problems. Preoperative assessment of the donor and recipient medical condition and meticulous attention to detail during the technical performance of OLTx are the mainstays in achieving a good outcome.

Does intraoperative hepatic artery flow predict arterial complications after liver transplantation?

BACKGROUND

Little is known about the value of intraoperative hepatic artery (HA) flow measurement on the development of HA complications in orthotopic liver transplantation (OLT). We undertook this study to see whether assessing HA flow at the OLT helps predict posttransplant HA complications (HA thrombosis or stenosis).

METHODS

Four hundred and eleven consecutive OLT in 367 adult patients who received grafts between November 1992 and August 1995 were reviewed. Of these, 259 grafts in 255 patients with at least 1 year of follow-up and with complete data were studied. HA flow, portal vein flow, percentage of cardiac index going to HA (HA/CI), HA flow per 100 g of liver tissue, mean arterial pressure, central venous pressure, and CI were analyzed. Preservation injury was assessed by posttransplant alanine aminotransferase and aspartate aminotransferase levels.

RESULTS

Thirty-four patients with 35 grafts developed HA thrombosis or stenosis during a median follow-up time of 29 months. HA complications occurring within the first 100 days of OLT were classified as early complications. HA flow at the time of surgery and percentage of CI going to the liver were found to be significant variables in early HA complications. Hepatic hemodynamics were not different in the late HA complication group compared to the control. Systemic hemodynamics and posttransplant alanine amino-transferase and aspartate aminotransferase levels were similar in all three groups. Logistic regression analysis showed that patients with HA flows less than 400 ml/min were more than 5 times as likely to develop HA complications (risk ratio 5.1).

CONCLUSIONS

HA flow measurement should be obtained at the time of OLT and may help to predict early but not late posttransplant HA complications. Patients with HA flows less than 400 ml/min or HA/CI values of less than 7% may carry a higher risk for HA stenosis or thrombosis and may need close surveillance to detect such problems.

A prospective randomised trial of bile duct reconstruction at liver transplantation: T tube or no T tube?

A prospective randomised study of end-to-end bile duct reconstruction with or without T-tube drainage during orthotopic liver transplantation (OLT) was undertaken in 60 patients well matched for age, sex, aetiology of liver disease, operative blood loss, cold ischaemic time, preoperative serum bilirubin level and Child-Pugh score. Significant biliary complications in the T tube group occurred in five patients and included bile duct stricture (n = 2), bile leak/peritonitis (n = 1) and cholangitis (n = 2). Bile duct strictures occurred in six patients in the no T tube group (P > 0.05, NS). Hepatic artery stenosis was identified in one patient from each group in association with a biliary stricture. Biliary complications in both groups were associated with a prolonged graft cold ischaemic time (P < 0.01). As no significant difference was noted in the number of early and late biliary complications between the two groups, the routine use of a T tube has been discontinued.

Hepatic artery stenosis after liver transplantation--incidence, presentation, treatment, and long term outcome

Little is known about hepatic artery (HA) patency and patient clinical course when the nonthrombosed HA has been revised. We undertook this study to evaluate the risk factors in the development of HA stenosis and to assess the impact of HA revision on the outcome. A total of 857 adult consecutive OLT in 780 patients performed over a 6-year period were studied. Patients who underwent revision of their nonthrombosed but stenotic HA were reviewed for patient/graft survival, method of HA revision, incidence of biliary strictures, and long-term HA patency. Overall 39 patients (5%) with 41 allografts underwent HA revision for stenosis. Median time to diagnosis was 100 days posttransplant (range 1-1220 days). HA flow at the time of OLT was found to be the only significant variable of an anastomotic stenosis. No risk factor could be identified for the graft HA stenosis. Treatment methods included resection of the stenotic segment with primary reanastomosis (n = 17), aortohepatic iliac artery graft (n = 11), interposition vein graft (n = 4), vein patch angioplasty (n = 2), interposition artery graft (n = 1), and percutaneous transluminal balloon angioplasty (n = 6). Postrevisional HA patency was demonstrated in 32 (78%) cases. At a median follow-up of 25 months, 26 patients (67%) were asymptomatic with good liver function. Nine patients had developed biliary strictures. Seven patients had undergone retransplantation and 8 patients had died. The actuarial patient and graft survivals at 4 years in the patients with revised HA were 65% and 56%, respectively. HA stenosis requiring revision is an infrequent occurrence after OLT. Long-term patency of the revised HA is good. Revision of the HA may help prevent biliary strictures and allow for good long-term graft function in the majority of patients.

A prospective randomised trial of bile duct reconstruction at liver transplantation: T tube or no T tube?

A prospective randomised study of end-to-end bile duct reconstruction with or without T-tube drainage during orthotopic liver transplantation (OLT) was undertaken in 60 patients well matched for age, sex, aetiology of liver disease, operative blood loss, cold ischaemic time, preoperative serum bilirubin level and Child-Pugh score. Significant biliary complications in the T tube group occurred in five patients and included bile duct stricture (n = 2), bile leak/peritonitis (n = 1) and cholangitis (n = 2). Bile duct strictures occurred in six patients in the no T tube group (P > 0.05, NS). Hepatic artery stenosis was identified in one patient from each group in association with a biliary stricture. Biliary complications in both groups were associated with a prolonged graft cold ischaemic time (P < 0.01). As no significant difference was noted in the number of early and late biliary complications between the two groups, the routine use of a T tube has been discontinued.

Hepatic artery angioplasty after liver transplantation: experience in 21 allografts

PURPOSE

To assess whether percutaneous transluminal angioplasty (PTA) can help prolong allograft survival and improve allograft function in patients with hepatic artery stenosis after liver transplantation.

PATIENTS AND METHODS

Hepatic artery PTA was attempted in 19 patients with 21 allografts over 12 years. The postangioplasty clinical course was retrospectively analyzed. Liver enzyme levels were measured before and after PTA to determine if changes in liver function occurred after successful PTA.

RESULTS

Technical success was achieved in 17 allografts (81%). Retransplantation was required for four of 17 allografts (24%) in which PTA was successful and four of four allografts in which PTA was unsuccessful; this difference was significant (P = .03). Two major procedure-related complications occurred: an arterial leak that required surgical repair and an extensive dissection that necessitated retransplantation 14 months after PTA. Hepatic failure necessitated repeat transplantation in seven cases from 2 weeks to 27 months (mean, 8.4 months) after PTA. Six patients died during follow-up, three of whom had undergone repeat transplantation. Markedly elevated liver enzyme levels at presentation were associated with an increased risk of retransplantation or death regardless of the outcome of PTA.

CONCLUSION

PTA of hepatic artery stenosis after liver transplantation is relatively safe and may help decrease allograft loss due to thrombosis. Marked allograft dysfunction at presentation is a poor prognostic sign; thus, timely intervention is important.