Hepatic outflow obstruction at middle hepatic vein tributaries or inferior right hepatic veins after living donor liver transplantation with modified right lobe graft: comparison of CT and Doppler ultrasound. AJR Am J Roentgenol. 2009;193:745-751. [PMID: 19696288 DOI: 10.2214/ajr.08.2145]

Feasibility of modified endarterectomized aortic allograft for middle hepatic vein reconstruction in living donor liver transplantation: A retrospective cohort study

BACKGROUND

Cryopreserved allografts and artificial vascular grafts were introduced to meet the increasing demand for adequate vascular substitutes for middle hepatic vein (MHV) reconstruction during living donor liver transplantation (LDLT). This study evaluated patency outcomes after engraftment of a modified endarterectomized aortic allograft (MEAA) without any additional patches.

METHODS

This retrospective double-arm study was conducted in single tertiary referral center between January 2015 and July 2018. Of 1,047 adult patients who underwent single-graft LDLT with a modified right lobe (MRL), 111 patients who received grafts with MHV reconstruction using MEAA were selected. The control group comprised 434 patients who underwent MHV reconstruction using iliac vein allografts. The main outcome measure was the short-term patency of the MEAA. The secondary outcome was the incidence of graft-associated complications.

RESULTS

Clinically significant MHV stenoses requiring stenting occurred in 3 patients (2.7%) in the MEAA group and in 17 patients (3.9%) in the iliac vein group (P = 0.778). Three-month and one-year patency rates on Doppler ultrasonography and computed tomography were 88.5% and 54.0%, respectively, in the MEAA group and 84.0% and 42.2%, respectively, in the iliac vein group, indicating the superior patency outcomes with MEAA (P = 0.017).

CONCLUSIONS

MHV reconstruction using MEAA during LDLT of a MRL graft is technically simple, achieves clinical outcomes comparable to iliac vein grafts, and is effective in expanding the allograft vessel pool for LDLT.

Doppler ultrasound follow-up of middle hepatic vein tributaries-interposition vessel graft in recipients of living donor liver transplantation using modified right lobe grafts

OBJECTIVE

To investigate the value of Doppler ultrasound (US) in recipients of living donor liver transplantation (LDLT) using modified right-lobe grafts (mRLGs) with obstruction of the middle hepatic vein tributaries (MHVTs)-interposition vessel graft (IVG).

METHODS

This study included 240 consecutive LDLT recipients in whom 564 MHVTs (>5 mm) were reconstructed using IVG. Regular follow-up Doppler US was performed to assess the patency of the MHVTs-IVG and, if there was an obstruction, to evaluate for the establishment of collateral drainage. MHVTs with obstruction were subdivided into those with and without intrahepatic veno-venous collaterals on Doppler US and were correlated with CT scans.

RESULTS

MHVTs-IVG obstruction was identified in 137 patients with 227 MHVTs on follow-up Doppler US (6.2  ±  4.7 months). 90 patients with 149 MHVTs in whom the time interval between Doppler US and contrast-enhanced dynamic CT scans was <1 week were classified into either collateral (68 patients with 121 MHVTs) or non-collateral (22 patients with 28 MHVTs) groups. The presence of intrahepatic veno-venous collaterals on Doppler US were significantly related to no remarkable hepatic venous congestion on CT by both per-patient and per-vein analyses (66 of 68 patients (97.1%) and 118 of 121 MHVTs (97.5%), p < 0.001 and p < 0.001, respectively).

CONCLUSION

On Doppler US follow-up of LDLT recipients using mRLGs, identification of intrahepatic veno-venous collaterals associated with obstruction of MHVTs-IVG suggests no remarkable hepatic venous congestion. Advances in knowledge: When an obstruction of a MHVTs-IVG is encountered on Doppler US follow-up of LDLT recipients using mRLGs, no further evaluation with CT is warranted if intrahepatic veno-venous collaterals are observed on Doppler US, as this finding suggests no remarkable hepatic congestion.

Modified triangular hepatic vein reconstruction for preventing hepatic venous outflow obstruction in pediatric living donor liver transplantation using left lateral segment grafts

HVOO can be a critical complication in pediatric LDLT. The aim of this study was to evaluate a modified triangular technique of hepatic vein reconstruction for preventing HVOO in pediatric LDLT. A total of 298 pediatric LDLTs were performed using a left lateral segment graft by 2 methods for reconstruction of the hepatic vein. In 177 recipients, slit-shaped anastomosis was indicated with partial clamp of the IVC. A total of 121 recipients subjected to the modified triangular anastomosis with total clamp of the IVC. We compared the incidence of hepatic vein anastomotic complications between these 2 methods. Nine of the 177 cases (5.3%) treated with the conventional technique were diagnosed with outflow obstruction. All 9 cases underwent hepatic vein reconstruction with the slit-shaped hepatic vein anastomosis. In contrast, there were no cases of outflow obstruction in the 121 cases treated with the modified triangular anastomosis. The modified triangular technique of hepatic vein reconstruction with total clamping of the IVC was useful for preventing HVOO in pediatric LDLT.

Diagnosis, treatment and outcome of hepatic venous outflow obstruction in paediatric liver transplantation: 24-year experience at a single centre

BACKGROUND

Hepatic venous outflow obstruction after paediatric liver transplantation is an unusual but critical complication.

OBJECTIVES

To review the incidence, diagnosis and therapeutic modalities of hepatic venous outflow obstruction from a large national liver transplant unit.

MATERIALS AND METHODS

During the period from October 1992 to March 2016, 917 liver transplant procedures were performed with all types of grafts in 792 children. Transplants suspected to have early or delayed venous outflow obstruction were confirmed by percutaneous venography or surgical revision findings. Therapeutic intervention, recurrence and outcome were evaluated.

RESULTS

Twenty-six of 792 children (3.3%) experienced post-transplant hepatic venous outflow obstruction. These patients had been diagnosed from 1 day to 8.75 years after transplantation. Six occurred during the early post-transplant period; in three of them, the graft was lost. Seventeen patients were initially treated by balloon angioplasty with success; 11 of these experienced recurrences. Four stents were implanted; one was complicated by definitive occlusion. Three of the five surgical revisions were successful. The initial stenosis involved the inferior vena cava in 10 grafts, in isolation or associated with hepatic vein involvement. Mean follow-up was 79 months after transplantation. Eight grafts were lost.

CONCLUSION

Acute postoperative hepatic venous outflow obstruction was associated with poor prognosis. Diagnostic venography should be performed if there is any suspicion of venous outflow obstruction, even if first-line examinations are normal. Stenosis frequently involved the inferior vena cava. Angioplasty was a safe and efficient treatment for venous outflow obstruction despite frequent recurrence.

Diagnosis and treatment guidelines for aberrant portal hemodynamics: The Aberrant Portal Hemodynamics Study Group supported by the Ministry of Health, Labor and Welfare of Japan

Idiopathic portal hypertension (IPH), causing aberrant portal hemodynamics, is a disease with an as yet unidentified cause and no established treatment protocol. The Japanese research group on IPH in Japan was set up in 1975 by the Ministry of Health, Labor and Welfare. Extrahepatic portal obstruction and Budd-Chiari syndrome (BCS) have since been added to the group's research subjects. The aims of the research group are to accurately evaluate the current status of the three diseases in Japan, elucidate their etiology and pathogenesis, and develop new treatments. Due to the long-term efforts of the Japanese research group, aberrant portal hemodynamics has been investigated in a variety of aspects, from epidemiological and pathological studies to molecular biology analyses. As a result, it has been shown that there are abnormal genes in the liver, specific for IPH. In addition, pathological findings of BCS were internationally compared and the difference in findings between Japan and Europe (or North America) has been clarified. Furthermore, it was found that complication rates of hepatocellular carcinoma in BCS were higher in Japan. Based on the research, "Diagnosis and treatment of aberrant portal hemodynamics (2001)", including diagnostic criteria for aberrant portal hemodynamics, was published in 2001. In 2013, it was revised to "Diagnosis and treatment guidelines for aberrant portal hemodynamics (2013)" after the incorporation of diagnosis and treatment in accordance with its current status.

Left lobe graft poses a potential risk of hepatic venous outflow obstruction in adult living donor liver transplantation

Hepatic venous outflow obstruction (HVOO) is a critical complication after living donor liver transplantation (LDLT). This study aimed to evaluate the incidence of HVOO and the risk factors for HVOO in adults. From 2005 to 2015, 430 adult LDLT patients (right lobe [RL] graft, 270 patients; left lobe [LL] graft, 160 patients) were enrolled and divided into no HVOO (n = 413) and HVOO (n = 17) groups. Patient demographics and surgical data were compared, and risk factors for HVOO were analyzed. Furthermore, the longterm outcomes of percutaneous interventions as treatment for HVOO were assessed. HVOO occurred in 17 (4.0%) patients. The incidence of HVOO in patients receiving a LL graft was significantly higher than in those receiving a RL graft (8.1% versus 1.5%; P = 0.001). The body weight and caliber of hepatic vein anastomosis in the HVOO group were significantly lower compared with the no HVOO group (P = 0.02 and P = 0.008, respectively). Multivariate analysis revealed that only LL graft was an independent risk factor for HVOO (OR, 4.782; 95% CI, 1.387-16.488; P = 0.01). Among 17 patients with HVOO, 7 patients were treated with single balloon angioplasty, and 9 patients who developed recurrence were treated with repeated interventions. Overall, 6 patients underwent stent placement: 1 at the initial procedure, 3 at the second procedure for early recurrence, and 2 following repeated balloon angioplasty (≥3 interventions). These 6 patients experienced no recurrence. Overall graft survival was not significantly different between the HVOO and no HVOO groups (P = 0.99). In conclusion, the use of a LL graft was associated with HVOO, and percutaneous interventions were effective for treating adult HVOO after LDLT. Liver Transplantation 22 785-795 2016 AASLD.

Application of contrast-enhanced ultrasound after liver transplantation: Current status and perspectives

Liver transplantation is an effective treatment for patients with end-stage liver disease. Accurate imaging evaluation of the transplanted patient is critical for ensuring that the limited donor liver is functioning appropriately. Ultrasound contrast agents (UCAs), in combination with contrast-specific imaging techniques, are increasingly accepted in clinical use for the assessment of the hepatic vasculature, bile ducts and liver parenchyma in pre-, intra- and post-transplant patients. We describe UCAs, their technical requirements, the recommended clinical indications, image interpretation and the limitations for contrast-enhanced ultrasound applications in liver transplantation.

Long-term outcome of endovascular intervention in hepatic venous outflow obstruction following pediatric liver transplantation

The purpose of our study was to address the long-term outcome of angioplasty and stent placement for hepatic venous outflow obstruction following pediatric liver transplantation. From October 1999 to December 2011, 20 stenotic lesions were confirmed to constitute hepatic venous outflow obstruction in 18 pediatric patients (13 boys, 5 girls) among 152 pediatric patients following liver transplantation and were managed with endovascular intervention. Stent placement was favored over additional angioplasty in patients of preadolescent or adolescent age (>8 years old), after 1 or 2 sessions of balloon angioplasty. The primary patency and assisted primary patency were estimated using the Kaplan-Meier method. A total of 32 procedures (24 balloon angioplasties, 8 stent placements) were conducted. The technical success rate was 90.6% (29/32). Clinical success was achieved in 15 of 18 patients (clinical success rate of 83.3%). Major complications did not occur in our study. Median follow-up was 91.5 months (interquartile range, 54.7-137.3 months) for the 18 patients. The 1-year, 3-year, 5-year, and 10-year primary patencies of the 20 treated lesions were 63.5%, 57.8%, 57.8%, and 57.8%, respectively. The 1-year, 3-year, 5-year, and 10-year assisted-primary patencies of the lesions were 100%, 100%, 100%, and 100%, respectively. Of the 6 patients of preadolescent or adolescent age, 5 patients underwent stent placement procedures, and the stents were patent during the follow-up period of 57.3-162.5 months (median, 72.7 months). In conclusion, endovascular intervention is very effective in hepatic venous outflow obstruction following pediatric liver transplantation. In addition, early stent placement in patients of preadolescent or adolescent age can provide a safe and favorable long-term outcome.

Postoperative haemodynamic changes in transplanted liver: Long-term follow-up with ultrasonography

OBJECTIVE

To investigate haemodynamic changes in the transplanted liver without postoperative complications.

METHODS

Colour Doppler ultrasound was used to monitor recipients of liver transplants who had no postoperative complications. The haemodynamic data for the hepatic vasculature were compared at different time-points during the first 4 years after liver transplantation.

RESULTS

A total of 144 liver transplant patients were enrolled in the study. Portal vein flow velocity decreased significantly from 72.1 ± 30.3 cm/s at 1 day to 44.2 ± 20.1 cm/s at 1 month after liver transplantation. Hepatic artery flow velocity was 61.4 ± 33.2 cm/s at day 1; it then decreased slowly but significantly to 48.3 ± 20.4 cm/s at 3 years after transplantation. There were 81 (56.3%) patients with high hepatic artery resistance index (HARI) (>0.80) and 19 (13.2%) with low HARI (<0.50) measured at least once during the 4-year follow-up examination.

CONCLUSIONS

Decreased portal vein flow velocity was the typical change observed during the first month after liver transplantation. Abnormal haemodynamic Doppler results should be interpreted with caution because they may not be clinically significant and may improve spontaneously.

Long-term outcome of percutaneous interventions for hepatic venous outflow obstruction after pediatric living donor liver transplantation: experience from a single institute

PURPOSE

To evaluate retrospectively the long-term outcome of percutaneous interventions for hepatic venous outflow obstruction (HVOO) occurring after pediatric living donor liver transplantation (LDLT).

MATERIALS AND METHODS

Between October 1997 and December 2012, 48 patients (24 boys, 24 girls; median age, 6 y) who had undergone LDLT were confirmed to have HVOO using percutaneous hepatic venography and manometry. All patients underwent percutaneous interventions, including balloon angioplasty with or without stent placement. Technical success, clinical success, patency rates, stent placement, and major complications were evaluated.

RESULTS

Technical success was achieved in 92 of 93 sessions (99.0%) and in 47 of 48 patients (97.9%), and clinical success was achieved in 41 of 48 patients (85.4%). During the follow-up period (range, 1-182 mo; median, 51.5 mo), 28 patients were treated with a single session of balloon angioplasty, and 20 patients who developed recurrent stenosis were treated with repeated percutaneous interventions. The rates of primary and primary-assisted patency at 1, 3, 5, and 10 years after balloon angioplasty were 64%, 57%, 57%, and 52% (primary patency) and 98%, 95%, 95%, and 95% (primary-assisted patency). Of six patients with stent placement, four had no recurrent HVOO after the stent placement, but two developed recurrent stenosis. The stent migrated to the right atrium in one patient.

CONCLUSIONS

Percutaneous interventions were effective treatments for HVOO after LDLT.

Adult-to-adult living donor liver transplantation for acute liver failure in China

AIM: To investigate the long-term outcome of recipients and donors of adult-to-adult living-donor liver transplantation (AALDLT) for acute liver failure (ALF).

METHODS: Between January 2005 and March 2010, 170 living donor liver transplantations were performed at West China Hospital of Sichuan University. All living liver donor was voluntary and provided informed consent. Twenty ALF patients underwent AALDLT for rapid deterioration of liver function. ALF was defined based on the criteria of the American Association for the Study of Liver Diseases, including evidence of coagulation abnormality [international normalized ratio (INR) ≥ 1.5] and degree of mental alteration without pre-existing cirrhosis and with an illness of < 26 wk duration. We reviewed the clinical indications, operative procedure and prognosis of AALDTL performed on patients with ALF and corresponding living donors. The potential factors of recipient with ALF and corresponding donor outcome were respectively investigated using multivariate analysis. Survival rates after operation were analyzed using the Kaplan-Meier method. Receiver operator characteristic (ROC) curve analysis was undertaken to identify the threshold of potential risk factors.

RESULTS: The causes of ALF were hepatitis B (n = 18), drug-induced (n = 1) and indeterminate (n = 1). The score of the model for end-stage liver disease was 37.1 ± 8.6, and the waiting duration of recipients was 5 ± 4 d. The graft types included right lobe (n = 17) and dual graft (n = 3). The mean graft weight was 623.3 ± 111.3 g, which corresponded to graft-to-recipient weight ratio of 0.95% ± 0.14%. The segment Vor VIII hepatic vein was reconstructed in 11 right-lobe grafts. The 1-year and 3-year recipient’s survival and graft survival rates were 65% (13 of 20). Postoperative results of total bilirubin, INR and creatinine showed obvious improvements in the survived patients. However, the creatinine level of the deaths was increased postoperatively and became more aggravated compared with the level of the survived recipients. Multivariate analysis showed that waiting duration was independently correlated with increased mortality (P = 0.014). Furthermore, ROC curve revealed the cut-off value of waiting time was 5 d (P = 0.011, area under the curve = 0.791) for determining the mortality. The short-term creatinine level with different recipient’s waiting duration was described. The recipients with waiting duration ≥ 5 d showed the worse renal function and higher mortality than those with waiting duration < 5 d (66.7% vs 9.1%, P = 0.017). In addition, all donors had no residual morbidity. Furthermore, univariate analysis did not show that short assessment time induced the high morbidity (P = 0.573).

CONCLUSION: Timely AALDLT for patients with ALF greatly improves the recipient survival. However, further systemic review is needed to investigate the optimal treatment strategy for ALF.

Obstruction at middle hepatic venous tributaries in modified right lobe grafts after living-donor liver Transplantation: diagnosis with contrast-enhanced US

PURPOSE

To investigate the ability of contrast material-enhanced ultrasonography (US) to help diagnose obstruction of middle hepatic venous (MHV) tributaries soon after living-donor liver transplantation with modified right lobe grafts.

MATERIALS AND METHODS

The institutional review board approved the study and waived requirement for informed consent. Sixty-five consecutive patients (48 men, 17 women; mean age, 52.8 years; range, 33-69 years) who underwent living-donor liver transplantation with modified right lobe grafts between February and May 2009 were included. All patients underwent contrast-enhanced US and Doppler US on postoperative day 1 and underwent computed tomography (CT) within 7 days after US. At contrast-enhanced US, parenchymal enhancement patterns in the territory of each MHV tributary during arterial and portal venous phases were evaluated. With use of most frequent enhancement patterns in patients with obstruction at MHV tributaries as a criterion, diagnostic performance of contrast-enhanced US was compared with that of Doppler US for diagnosis of obstruction at MHV tributaries; CT was the reference standard. Generalized estimating equations were used to adjust for data clustering.

RESULTS

Of 148 MHV tributaries in 65 patients, 36 (24.3%) in 31 patients were diagnosed as obstructed at CT. With arterial high echogenicity or portal low echogenicity used as a criterion for hepatic venous obstruction, contrast-enhanced US had sensitivity, specificity, and accuracy of 91% (33 of 36), 97% (109 of 112), and 95% (142 of 148), respectively, whereas Doppler US had values of 83% (30 of 36), 86% (97 of 112), and 85% (127 of 148), respectively. Contrast-enhanced US was significantly more specific and accurate than Doppler US for diagnosis of obstruction at MHV tributaries (P=.024 and .01, respectively). Arterial high echogenicity was noted only in the hepatic venous obstruction group.

CONCLUSION

Contrast-enhanced US can help accurately assess hepatic venous obstruction at MHV tributaries after living-donor liver transplantation with a modified right lobe graft. Contrast-enhanced US was significantly more specific than Doppler US, with arterial hyperenhancement in the affected area being specific to hepatic venous obstruction.

Standard hepatic vein reconstruction with patch plasty using the native portal vein in adult living donor liver transplantation

An outflow obstruction of the hepatic vein is a critical complication after living donor liver transplantation (LDLT) and occasionally leads to hepatic failure. Here we introduce a simple method for preventing outflow obstructions by patch plasty in adult LDLT. Between September 2001 and May 2010, 468 adult LDLT procedures were performed at Kyoto University Hospital. We harvested each recipient's portal vein (PV) from the extirpated liver for a patch. We intended to re-form several orifices of the hepatic veins into a single, large orifice. The patch was attached to the anterior wall of the re-formed orifice on the bench. After we put in the liver graft, the procedure for the hepatic vein anastomosis to the inferior vena cava was simple enough that the warm ischemia time was reduced. Three of the 468 cases were diagnosed with an outflow obstruction. All 3 cases underwent hepatic vein reconstruction without patch plasty. In contrast, none of the 159 cases that underwent LDLT with patch plasty suffered from an outflow obstruction, regardless of the liver graft type. The procedure for hepatic vein plasty using a patch from the native PV is simple and elegant and results in excellent outcomes. We propose this as the standard procedure for hepatic vein reconstruction in adult LDLT.

Acute outflow obstruction of hepatic veins in rabbits: quantitative analysis of hepatic perfusion with contrast-enhanced sonography

OBJECTIVES

To compare time-enhancement curve parameters of contrast-enhanced sonography in acute partial hepatic venous outflow obstruction with those of a baseline study.

METHODS

Contrast-enhanced sonography was performed in 11 rabbits with bolus administration of a sulfur hexafluoride contrast agent (0.1 mL/kg). After baseline scanning for 3 minutes, a 5.3F balloon catheter was placed into the left hepatic vein. Obstruction was artificially induced by 0.4-mL balloon inflation, and sonography was repeatedly performed thereafter. On images stored with 1-second intervals, 2 × 2-mm regions of interest were placed, and mean luminosity was measured. Time-enhancement curves were plotted, and contrast arrival times, peak enhancement values, peak enhancement times, 50% wash-out times, and 3-minute wash-out rates were obtained. Paired t tests were performed to evaluate the significance of differences in the parameters between baseline and obstruction.

RESULTS

On baseline sonography, the median contrast arrival time, peak enhancement value, peak enhancement time, 50% wash-out time, and 3-minute wash-out rate were 6 (range, 4-8; mean ± SD, 5.9 ± 1.2) seconds, 188.5 (104.7-209.5; 178.4 ± 33.1) arbitrary units, 19 (14-27; 19.8 ± 4.1) seconds, 75 (60-101; 78.2 ± 13.9) seconds, and 89.7% (81.3%-95.1%; 88.4% ± 4.9%), respectively. With obstruction, those values were 7 (5-12; 6.9 ± 2.3) seconds, 202.8 (98.2-215.1; 186.0 ± 39.3) arbitrary units, 31 (17-59; 32 ± 11.6) seconds, 101 (47-136; 96.2 ± 23.6) seconds, and 79.2% (66.2%-88.8%; 79.1% ± 7.6%). Compared with baseline, the peak enhancement time was significantly delayed from 19 to 31 seconds (P = .0027), 50% wash-out time significantly delayed from 75 to 101 seconds (P = .0209), and 3-minute wash-out rate significantly decreased from 89.7% to 79.2% (P < .0001) with obstruction, but there were no significant differences in contrast arrival times and peak enhancement values (P = .0756 and .2179).

CONCLUSIONS

Contrast-enhanced sonography can provide quantitative assessment of microbubble congestion in partial hepatic venous outflow obstruction. The peak enhancement time and 50% wash-out time are delayed and 3-minute wash-out rate is decreased in rabbits with artificially induced obstruction compared with a baseline study.

Living donor liver transplantation

PURPOSE OF REVIEW

The widening gap between the growing number of liver transplant candidates and the supply of deceased donor organs became a strong motivation for the development of living donor liver transplantation (LDLT). LDLT has gone through its developmental phase and become an established life-saving procedure.

RECENT FINDINGS

Despite the challenging nature of the technique of LDLT, there have been continuous innovations. A better understanding of complex surgical anatomy and physiologic differences of partial hepatic allografts has helped to avoid graft congestion, small-for-size syndrome, or graft hypoperfusion from portal flow steal. LDLT for patients with high Model for End-Stage Liver Disease score can achieve comparable results with deceased donor liver transplantation (DDLT). Size limitation of partial grafts can be overcome with dual grafts. The extended application of LDLT for hepatocellular carcinoma beyond Milan criteria seems feasible but at the cost of slightly compromised survival. More information has become available for prospective donors about the consequences of living liver donation in terms of psychosocial impact.

SUMMARY

Although LDLT is still evolving, it has become the most effective alternative to DDLT. Proven or potential benefit of LDLT include the superior quality of the allograft despite the smaller size, selection of proper timing for transplantation and a reduced waiting time, which prevents waiting list mortality.