SURGICAL REPAIR FOR LATE-ONSET HEPATIC VENOUS OUTFLOW BLOCK AFTER LIVING-DONOR LIVER TRANSPLANTATION

Metallic Stents for Hepatic Venous Outflow Obstruction After Living-Donor Liver Transplantation and their Therapeutic Effects

BACKGROUND

Living-donor liver transplantation (LDLT) is established as a standard therapy for end-stage liver disease; however, vessel reconstruction is more demanding due to the short length and small size of the available structures compared with deceased-donor whole liver transplantation. Interventional radiology (IR) has become the first-line treatment for vascular complications after LDLT. Hepatic venous outflow obstruction (HVOO) is a life-threatening complication after LDLT. The aim of this study of 592 adult-to-adult LDLT cases was to investigate the safety and efficacy of stent implantation for HVOO after LDLT.

METHODS

Records of patients who developed HVOO requiring any treatment were collected with special reference to the metallic stent implantation. There were 232 left-side grafts and 360 right-side grafts. Sixteen cases developed HVOO after LDLT with an incidence rate of 2.7%, 5 with a left liver graft (2%), and 11 with a right-side graft (3%). The IR was attempted for 14 cases; among those, 8 cases were treated by stent implantation.

RESULTS

The technical success rate of the initial stent implantation was 100%. The pressure gradient at the stenotic site significantly improved from 12.2 (range, 10.9-20.4 cm H2O) to 3.9 cm H2O (range, 1.4-8.2 cm H2O; P = .03). The volume of the congested graft liver decreased significantly from 1448 (range, 788-2170 mL) to 1265 mL (range, 748-1665 mL; P = .01), and the serum albumin level improved significantly from 3.3 (range, 1.7-3.7 g/dL) to 3.7 g/dL (range, 2.9-4.1 g/dL; P = .02). No procedure-related complication was noted, and the long-term stent patency was 100%.

CONCLUSION

Metallic stent implantation for stenotic venous anastomosis after LDLT is a safe and effective treatment.

Validation of Functional Assessment for Liver Resection Considering Venous Occlusive Area after Extended Hepatectomy

BACKGROUND

Previous studies demonstrated that liver function in a veno-occlusive region is approximately 40% of that in a non-veno-occlusive region after hepatectomy with excision of major hepatic vein. We validated the preoperative assessment of future remnant liver (FRL) function based on 40% decreased function of the veno-occlusive region.

METHODS

Sixty patients who underwent hepatectomy with excision of major hepatic vein were analyzed. The FRL functions of the veno-occlusive and non-veno-occlusive regions were calculated with 99mTc-galactosyl human serum albumin scintigraphy single-proton emission computed tomography fusion system and SYNAPSE VINCENT® preoperatively. Risk assessment for hepatectomy was evaluated based on indocyanine green retention at 15 min, and patients with insufficient FRL function were described as marginal.

RESULTS

The median volume and function of the veno-occlusive region per whole liver were 111 ml and 11.0%, respectively. When the function of the veno-occlusive region was presumed as 0%, 40%, and 100%, the FRL function was 62.5%, 68.4%, and 75.0% and 21, 15, and 7 patients were classified as marginal, respectively. When the function of the veno-occlusive region was presumed as 40%, the posthepatectomy liver failure (PHLF) rate of marginal patients was significantly higher than that of safe patients (46.7% vs 8.9%, P = 0.002). Multivariable analysis indicated that marginal FRL function based on 40% decreased function of the veno-occlusive region was the only independent risk factor for PHLF (odds ratio 8.97, P = 0.002) after extended hepatectomy.

CONCLUSION

Assessment of preoperative FRL function based on 40% decreased function of the veno-occlusive region may have high validity.

IVC angioplasty using an autologous vascular graft for IVC stenosis due to metallic stent in a pediatric liver transplant

A 12-year-old girl underwent LDLT using a left lobe graft for hepatic dysfunction associated with citrin deficiency. A continuous anastomosis suture technique was performed between the recipient's IVC and the donor's left hepatic vein. At age 14, the patient developed intractable ascites. Venography of the IVC and hepatic vein showed twisted-shape stenosis of the hepatic vein-IVC anastomosis with intravascular pressure gradient, probably due to the enlarged transplanted liver, for which a metallic stent was placed. The ascites disappeared, and the patient was making satisfactory progress eight months after surgery. However, nine months after surgery, the ascites appeared again with edema in the lower extremities. Since the stent that had been inserted was suspected of hampering the outflow of the graft liver and IVC, it was decided to conduct stent removal and IVC angioplasty. After intravascular exploration, the stent was removed. Angioplasty was performed. An autologous vascular graft patch was designed to be wedge-shaped to fit the incised part of the IVC, and it was sutured with 5-0 non-absorbable surgical sutures using a continuous suture technique. No postoperative complications or perioperative graft dysfunction were observed. The ascites decreased markedly, and the edema in the lower extremities disappeared. Thus, we were able to successfully perform IVC angioplasty using an autologous vascular graft patch in a patient who developed IVC stenosis after stenting. This procedure is one of the most effective treatment options, especially for pediatric patients requiring long-term vascular patency.

Living donor liver transplantation: looking back at my 30 years of experience

Since I moved from the National Cancer Center to Shinshu University, I have been performing living donor liver transplantation (LDLT), which is the only way to save the life of patients with end-stage liver disease. In June 1990, we performed the first LDLT that case was the first successful case in Japan. The patient remains healthy and is enjoying a normal life still 28 years after the transplant. In 1993, we successfully performed adult-to-adult LDLT, which was the first successful case in the world. The patient enjoyed a normal life for 17 years until she died at 70 years of age. For small children, the left liver of adult donors is too large to close the abdomen. However, in adolescents or adults, even when the whole right liver is used, the volume of the graft is too small. The concept of the standard liver volume (SLV) has proven very important for this procedure and is calculated as follows: 706.2 × body surface area + 2.4. We proposed a method for evaluating the congestion of the liver by Doppler ultrasound. In addition, we devised the right lateral sector graft. Over the years, we have contributed to LDLT in many ways and published many papers. We feel that our findings are quite useful not only for LDLT but also for other hepatectomy procedures.

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.

Optimizing hepatic venous outflow reconstruction for hepatic vein stenosis with indwelling stent in living donor liver retransplantation

The patient was a boy of 7 years and 5 months of age, who underwent LDLT for acute liver failure at 10 months of age. HV stent placement was performed 8 months after LDLT because of intractable HV stenosis. At 7 years of age, his liver function deteriorated due to chronic rejection. The patient therefore underwent living donor liver retransplantation from his father. The HV was transected with the stent in situ. The IVC was resected due to stenosis. The pericardial cavity was opened and detached around the IVC to elongate the IVC. The divided ends of the IVC were joined by suturing to the posterior wall of the IVC. A new triangular orifice was made by adding an incision on the anterior wall of the IVC. The graft HV was then anastomosed to the new orifice with continuous sutures in the posterior wall and interrupted sutures in the anterior wall using 5-0 non-absorbable sutures. Doppler ultrasound showed a triphasic waveform. We successfully performed HV reconstruction without a vascular graft. This is a feasible procedure for overcoming HV stenosis in LDLT patients with an indwelling stent.

Perioperative Anesthetic Management of Patients Having Liver Transplantation for Uncommon Conditions

This review focuses on the perioperative anesthetic management of patients having liver transplantation (LT) performed for several uncommon indications or in combination with rare pathology. Conditions discussed in the article include Alagille syndrome, hypertrophic cardiomyopathy, Gilbert's syndrome, porphyria, Wilson's disease, and Budd-Chiari syndrome. In comparison to other indications, LT in these settings is infrequent because of the low incidence of these pathologies. Most of these conditions (with the exception of Gilbert syndrome) are associated with a high probability of significant perioperative complications and increased mortality and morbidity. Experience in management of these unusual conditions is only gained over time. Developing clinical pathways for patients with these conditions should result in outcomes similar to LT performed for more common indications.

Safety and efficacy of venous reconstruction in liver resection using cryopreserved homologous veins

BACKGROUND

Only a few studies have reported the resection and reconstruction of major hepatic veins during hepatectomy. Here, we present our strategy and techniques for venous reconstruction with cryopreserved homologous veins, and describe the surgical outcome.

METHODS

Among 2,387 hepatectomy patients, 39 patients who required hepatic venous reconstruction were reviewed retrospectively. Venous reconstruction was performed to secure a non-congested liver remnant volume of at least 40% of the total liver volume.

RESULTS

There was no operative mortality, and the severe morbidity rate was 5% in this series. A total of 41 veins were reconstructed; 30 with homologous veins (73.2%) and 11 with autologous veins (26.8%), with the middle hepatic vein being the most frequent (n = 23, 56%). Interposition grafting was performed more often (P = 0.003), the length of the venous resection was longer (P = 0.007), and pathologic wall infiltration of the vein was revealed more often (P = 0.002) in the homologous graft group than in the autologous graft group. The 1-, 2-, and 3-year overall patency of the reconstructed veins was 55.4%, 46.3%, and 46.3%, respectively.

CONCLUSIONS

Aggressive venous reconstruction during hepatectomy using cryopreserved homologous veins is a feasible option with satisfactory short-term outcomes, and may be warranted to improve operative safety.

Indocyanine green fluorescence imaging in hepatobiliary surgery

Indocyanine green (ICG) is a fluorescent dye that has been widely used for fluorescence imaging during hepatobiliary surgery. ICG is injected intravenously, selectively taken up by the liver, and then secreted into the bile. The catabolism and fluorescence properties of ICG permit a wide range of visualization methods in hepatobiliary surgery. We have characterized the applications of ICG during hepatobiliary surgery into: 1) liver mapping, 2) cholangiography, 3) tumor visualization, and 4) partial liver graft evaluation. In this literature review, we summarize the current understanding of ICG use during hepatobiliary surgery. Intra-operative ICG fluorescence imaging is a safe, simple, and feasible method that improves the visualization of hepatobiliary anatomy and liver tumors. Intravenous administration of ICG is not toxic and avoids the drawbacks of conventional imaging. In addition, it reduces post-operative complications without any known side effects. ICG fluorescence imaging provides a safe and reliable contrast for extra-hepatic cholangiography when detecting intra-hepatic bile leakage following liver resection. In addition, liver tumors can be visualized and well-differentiated hepatocellular carcinoma tumors can be accurately identified. Moreover, vascular reconstruction and outflow can be evaluated following partial liver transplantation. However, since tissue penetration is limited to 5-10mm, deeper tissue cannot be visualized using this method. Many instances of false positive or negative results have been reported, therefore further characterization is required.

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.

Portal uptake function in veno-occlusive regions evaluated by real-time fluorescent imaging using indocyanine green

BACKGROUND & AIMS

Although recent advances in preoperative imaging have enabled accurate estimation of the regional liver volume with venous occlusion, the extent of functional decrease in such regions remains unclear. In this study, the portal uptake function in postoperative veno-occlusive regions and non-veno-occlusive regions was evaluated by intraoperative fluorescent imaging after intravenous injection of indocyanine green (ICG).

METHODS

In 22 liver resection patients and 23 recipients and 18 donors of liver transplantation, fluorescent intensity on the remnant liver or the liver graft was evaluated in real time following intravenous injection of ICG (0.0025 mg per 1 ml of remnant liver volume).

RESULTS

Plateau ICG concentrations were significantly lower in the veno-occlusive regions (C(VO)) than in the non-veno-occlusive regions (C(Non)) in liver resection patients (median [range], 0.75 [0.29-2.0]μg/ml vs. 3.0 [0.46-6.4]μg/ml, p<0.001), donors (0.69 [0.29-1.9]μg/ml vs. 2.4 [0.46-6.4]μg/ml, p<0.001), and recipients (0.75 [0.34-1.8]μg/ml vs. 1.8 [0.54-6.4]μg/ml, p<0.001). Distributions of the C(VO)/C(Non) and the ratio of the hepatic uptake rate constant in the veno-occlusive regions to that in non-veno-occlusive regions were both around 40% (mean ± standard deviation, 0.36 ± 0.17 and 0.42 ± 0.16, respectively). When the functional remnant liver volume was calculated as a sum of non-veno-occlusive regions and veno-occlusive regions multiplied by C(VO)/C(Non), its ratio to the total liver volume was correlated with the improved postoperative/preoperative ratio of prothrombin time.

CONCLUSIONS

Portal uptake function in veno-occlusive regions is approximately 40% of that in non-veno-occlusive regions. Intraoperative ICG-fluorescent imaging enables real-time evaluation of the extent of the functional decrease in veno-occlusive regions, enhancing accurate estimation of the hepatic functional reserve for determining the surgical indications and procedures.

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.

Morphometric analysis of conformational changes in hepatic venous system after right lobe living donor liver transplantation

AIM

  After living donor liver transplantation (LDLT), the graft liver regenerates to the standard liver volume. However, little is known about the influence of this phenomenon on the hepatic venous system.

METHODS

  Fourteen right lobe LDLT without the middle hepatic vein were included in this study. Computed tomography before and 1 month after LDLT was performed to measure the inflow angle of the right hepatic vein (RHV), the aspect ratio of the inferior vena cava (IVC), the coordinate position of IVC and diameter of RHV. In addition, the regeneration index (RI) was determined on each liver segment.

RESULTS

  RHV showed a clockwise rotation at early postoperative months, the average increase of the inflow angle being 14.5 ± 15.6 (mean ± standard deviation) degrees. IVC was shifted from right to left with a deformity to a long oval shape on horizontal sections. The center of IVC moved dorsally at an average of 0.55 ± 0.77 cm and leftward at an average of 0.82 ± 0.89 cm. Diameter of RHV decreased at an average of 0.65 ± 0.39 cm at its root. The extent of liver regeneration was more prominent in the posterior segment as compared to the anterior segment, the average RI values being 1.65 ± 0.65 and 1.17 ± 0.44, respectively (P < 0.05). Hepatic vein outflow block (HVOB) was encountered in two patients with a marked conformational deformity observed in the hepatic venous system at early postoperative months after LDLT.

CONCLUSION

  After right lobe LDLT, the hepatic venous system exhibits a profound conformational change, which most likely plays a role in the onset of HVOB.

Hepatic venous outflow obstruction in pediatric living donor liver transplantation using left-sided lobe grafts: Kyoto University experience

The goals of this study were to evaluate the incidence of hepatic venous outflow obstruction (HVOO) in pediatric patients after living donor liver transplantation (LDLT) using left-sided lobe grafts and to assess the therapeutic modalities used for the treatment of this complication at a single center. Four hundred thirteen primary LDLT procedures were performed with left-sided lobe grafts between 1996 and 2006. All transplants identified with HVOO from a cohort of 380 grafts with survival greater than 90 days were evaluated with respect to the patient demographics, therapeutic intervention, recurrence, and outcome. Seventeen cases (4.5%) were identified with HVOO. Eight patients experienced recurrence after the initial balloon venoplasty. Two patients finally required stent placement after they experienced recurrence shortly after the initial balloon venoplasty. A univariate analysis revealed that a smaller recipient-to-donor body weight ratio and the use of reduced grafts were statistically significant risk factors. The cases with grafts with multiple hepatic veins had a higher incidence of HVOO. In conclusion, the necessity of repeated balloon venoplasty and stent placement was related to poor graft survival. Therefore, the prevention of HVOO should be a high priority in LDLT. When grafts with multiple hepatic veins and/or significant donor-recipient size mismatching are encountered, the use of a patch graft is recommended. Stent placement should be carefully considered because of the absence of data on the long-term patency of stents and stent-related complications. New stenting devices, such as drug-eluting and biodegradable stents, may be promising for the management of HVOO.

Impact of Graft Hepatic Vein Inferior Vena Cava Reconstruction with Graft Venoplasty and Inferior Vena Cava Cavoplasty in Living Donor Adult Liver Transplantation Using a Left Lobe Graft

BACKGROUND

Hepatic venous reconstruction is critical in living donor adult liver transplantation (LDALT) because outflow obstruction in small for size graft may lead to graft dysfunction or loss. We describe the usefulness of venoplasties of the graft hepatic vein (HV) and graft HV-recipient inferior vena cava (IVC) reconstruction in LDALT using a left lobe graft.

METHODS

Sixty patients who underwent LDALT were studied. We divided the patients into following two groups: venoplasty group (n=30) and control group (n=30). For the patients with venoplasty group, venoplasty of the graft and recipient IVC cavoplasty was made to widen the orifice. Comparison examination of a background factors and postoperative bilirubin and the ascites was carried out.

RESULTS

The mean graft volume standard liver volume ratio (GV/SLV) did not have the difference at 41.7% of venoplasty group, and 42.1% of control group (p=NS). The diameter of the hepatic vein in control and venoplasty group before and after venoplasty is 26.9+/-5.5, 28.2+/-2.9, and 34.1+/-3.9 mm, respectively. The diameter of the hepatic vein after venoplasty is larger than that of before venoplasty and of control (P<0.05). Mean total bilirubin level on postoperative day (POD) 7 is 13.8+/-9.3 mg/dl in control group and 7.0+/-3.3 mg/dl in venoplasty group (P<0.05). Mean amount of ascites on POD 7 and 14 are 1576+/-1113 and 1397+/-1661 cc in control group, and 736+/-416 and 550+/-385 cc in venoplasty group, respectively (P<0.05). Two-year survival rate is 75.2 % in control group and 86.6 % in venoplasty group (P<0.05).

CONCLUSIONS

We conclude that in LDALT using left lobe graft, HV-IVC reconstruction with graft venoplasty and IVC cavoplasty is useful not only to prevent outflow block but also to improve graft function.

New hepatic vein reconstruction in left liver graft

The incidence of hepatic venous stenosis is higher in partial liver transplantation. New methods for hepatic venous reconstruction in left liver transplantation, which secure wide anastomosis, were devised and are reported here. In the graft, the right side of the middle hepatic vein or the left side of the left hepatic vein was cut longitudinally and a rectangular-shaped vein patch was attached for venoplasty. In the recipient, after the left and middle hepatic veins were joined, the right side of the middle hepatic vein was cut toward the closed right hepatic vein, making a horizontal cavotomy for anastomosis. Of 92 patients who underwent conventional hepatic vein reconstruction, 3 were complicated by hepatic venous stenosis (median follow-up 43 months). By contrast, there were no hepatic vein complications in the 20 patients who underwent the new technique (7 months). The current method appears to be technically feasible for outflow reconstruction in left liver graft transplantation.