Balloon dilatation for treatment of hepatic venous outflow obstruction following pediatric liver transplantation

Diagnostic accuracy of CT and Doppler US for hepatic outflow obstruction after pediatric liver transplantation using left lobe or left lateral section grafts

PURPOSE

The aim of this study was to evaluate diagnostic accuracy and to establish computed tomography (CT) and Doppler ultrasonography (US) criteria for hepatic outflow obstruction after pediatric liver transplantation (LT) using left lobe (LL) or left lateral section (LLS) grafts.

METHODS

Pediatric patients who underwent LT using LL or LLS grafts between January 1999 and December 2021 were retrospectively included. The diagnostic performance of Doppler US and CT parameters for hepatic outflow obstruction was calculated using receiver operating characteristic (ROC) curve analysis. A diagnostic decision tree model combining the imaging parameters was developed.

RESULTS

In total, 288 patients (150 girls; median age at LT, 1.8 years [interquartile range, 0.9 to 3.6 years]) were included. Among the Doppler US parameters, venous pulsatility index (VPI) showed excellent diagnostic performance (area under the ROC curve [AUROC], 0.90; 95% confidence interval [CI], 0.86 to 0.93; Youden cut-off value, 0.40). Among the CT parameters, anastomotic site diameter (AUROC, 0.92; 95% CI, 0.88 to 0.95; Youden cut-off, 4.2 mm) and percentage of anastomotic site stenosis (AUROC, 0.88; 95% CI, 0.84 to 0.92; Youden cut-off, 35%) showed excellent and good diagnostic performance, respectively. A decision tree model combining the VPI, peak systolic velocity, and percentage of anastomotic site stenosis stratified patients according to the risk of hepatic outflow obstruction.

CONCLUSION

VPI, anastomotic site diameter, and percentage of anastomotic site stenosis were reliable imaging parameters for diagnosing hepatic outflow obstruction after pediatric LT using LL or LLS grafts.

Management of Established Small-for-size Syndrome in Post Living Donor Liver Transplantation: Medical, Radiological, and Surgical Interventions: Guidelines From the ILTS-iLDLT-LTSI Consensus Conference

Small-for-size syndrome (SFSS) following living donor liver transplantation is a complication that can lead to devastating outcomes such as prolonged poor graft function and possibly graft loss. Because of the concern about the syndrome, some transplants of mismatched grafts may not be performed. Portal hyperperfusion of a small graft and hyperdynamic splanchnic circulation are recognized as main pathogenic factors for the syndrome. Management of established SFSS is guided by the severity of the presentation with the initial focus on pharmacological therapy to modulate portal flow and provide supportive care to the patient with the goal of facilitating graft regeneration and recovery. When medical management fails or condition progresses with impending dysfunction or even liver failure, interventional radiology (IR) and/or surgical interventions to reduce portal overperfusion should be considered. Although most patients have good outcomes with medical, IR, and/or surgical management that allow graft regeneration, the risk of graft loss increases dramatically in the setting of bilirubin >10 mg/dL and INR>1.6 on postoperative day 7 or isolated bilirubin >20 mg/dL on postoperative day 14. Retransplantation should be considered based on the overall clinical situation and the above postoperative laboratory parameters. The following recommendations focus on medical and IR/surgical management of SFSS as well as considerations and timing of retransplantation when other therapies fail.

Incidence of superficial left hepatic vein and its usability for graft hepatic vein venoplasty in pediatric liver transplantation

BACKGROUNDS

The anatomy of the left hepatic vein (LHV) is variable; thus, it should be considered for graft hepatic vein (GHV) venoplasty for left lateral section (LLS) and left liver grafts. This study assessed the incidence of superficial LHV (sLHV) branches according to LHV anatomy and its usability for GHV venoplasty in pediatric liver transplantation (LT).

METHODS

This study consisted of three parts: (1) anatomical classification of LHV variations and the incidence of sLHV branches; (2) morphometric simulative analysis of GHV reconstruction and (3) clinical application based on LHV anatomy.

RESULTS

The LHV anatomy of 248 potential LLS graft donors was classified into four types according to the number and location of GHV openings: one single opening (type 1; n = 186 [75.0%]), two large openings (type 2; n = 35 [14.1%]), one large and one small adjacent opening (type 3; n = 14 [5.6%]), and two large widely-separated openings (type 4; n = 13 [5.2%]). An sLHV branch was identified in 87 of 248 (35.1%) donor livers. Morphometric analysis of simulative GHV venoplasty with an sLHV branch increased GHV diameters by 30% in type 1 LLS grafts and 20% in type 2/3 LLS grafts. An analysis of 50 consecutive patients who underwent pediatric LT showed that the 2-year rates of GHV obstruction were 2.0% with LLS grafts and 0% with left liver grafts.

CONCLUSIONS

The GHV orifice can be enlarged through LHV anatomy-based unification venoplasty. Unification venoplasty with an sLHV branch provided sufficient enlargement of the GHV orifice.

Understanding Local Hemodynamic Changes After Liver Transplant: Different Entities or Simply Different Sides to the Same Coin?

Liver transplantation is an extremely complex procedure performed in an extremely complex patient. With a successful technique and acceptable long-term survival, a new challenge arose: overcoming donor shortage. Thus, living donor liver transplant and other techniques were developed. Aiming for donor safety, many liver transplant units attempted to push the viable limits in terms of size, retrieving smaller and smaller grafts for adult recipients. With these smaller grafts came numerous problems, concepts, and definitions. The spotlight is now aimed at the mirage of hemodynamic changes derived from the recipients prior alterations. This article focuses on the numerous hemodynamic syndromes, their definitions, causes, and management and interconnection with each other. The aim is to aid the physician in their recognition and treatment to improve liver transplantation success.

Pediatric Liver Transplantation: Long-Term Follow-Up Issues

Pediatric liver transplant is an established life-saving procedure for children with end-stage liver diseases, achieving excellent graft and patient survival but with effects on quality of life and psychological welfare in the long-term. With the natural increase in the number of pediatric transplant patients becoming adults, it is essential to successfully plan and manage issues affecting late outcomes in the vulnerable pediatric transplant population. This study offers an overview of the long-term surgical complications, the consequences of immunosuppression (such as posttransplant diabetes, hypertension, cardiovascular disease, and renal dysfunction), and the infection and malignancy risks. Finally, because quality of life is now an inclusive measurement of patient satisfaction, guidance on how to facilitate the transition to adulthood, empowering transplant recipients, is also provided.

Funneling venoplasty for anomalous graft left hepatic vein in living donor liver transplantation using a split left lateral section graft for an infant patient

The left lateral section (LLS) can have an unusual variant left hepatic vein (LHV) anatomy. We present a case of customized funneling venoplasty of the graft LHV in a 22-month-old girl diagnosed with ornithine transcarbamylase deficiency undergoing deceased donor liver transplantation (LT) using a split LLS graft. The split LLS graft weighed 350 g, yielding a graft-to-recipient weight ratio of 3.2%. Notably, the graft LHV opening was located at the graft liver cut surface, which was only 1 cm in size and 2 cm away from the cephalad apex of the LLS graft. Since such a variant location of the small LHV opening was unsuitable for direct anastomosis, we performed a funneling venoplasty using an inferior vena cava fragment homograft obtained from the same donor. The graft implantation was performed according to standard procedures of infant split LT. Follow-up imaging studies showed no vascular complications. The patient recovered uneventfully from the LT operation. She had normal blood test findings, including normal ammonia level. She has been doing well for 6 months after the transplantation. In conclusion, our surgical technique using a funneling venoplasty enabled successful reconstruction of the anomalous graft LHV. Our results suggest that individualized reconstruction techniques should be applied to infant patients undergoing LT using a LLS graft with variant types of graft LHV anatomy.

Outflow vein venoplasty of left lateral section graft for living donor liver transplantation in infant recipients

The orifice size of the LHV trunk in LLS grafts is often too small for direct anastomosis. Several methods were developed to enlarge the graft and recipient hepatic vein orifices. This study described our surgical techniques to secure hepatic vein reconstruction in infant recipients and analyzed the patency outcomes. Twelve infants undergoing pediatric LDLT were selected during 2-year study period between January 2018 and December 2019. Surgical techniques and vascular complications of graft hepatic vein outflow were analyzed. The mean recipient age was 12.5 ± 4.5 months; mean body weight was 9.4 ± 1.0 Kg; and mean graft-recipient weight ratio was 2.8 ± 0.6%. Primary diseases were biliary atresia in six patients, metabolic diseases in two, hepatoblastoma in two, and acute liver failure in two. Eight LLS grafts were recovered through an open method, and four LLS grafts were recovered through a laparoscopic method. A small superficial LHV branch was present in five of 12 LLS grafts, which was opened to widen the graft hepatic vein orifice. Incision-and-patch venoplasty was performed in 10, unification venoplasty in 1 and no venoplasty in 1. All four LLS grafts recovered through a laparoscopic approach required circumferential vein patch because of very short hepatic vein stump. No patient experienced graft hepatic vein-associated vascular complications during the follow-up period of 19.3 ± 9.3 months. Our surgical techniques with incision-and-patch venoplasty for LLS grafts is beneficial to reduce the risk of hepatic vein outflow obstruction in recipients receiving LLS grafts.

Third retransplantation using a whole liver graft for late graft failure from hepatic vein stent stenosis in a pediatric patient who underwent split liver retransplantation

We present a case of third retransplantation using a whole liver graft in a 13-year-old girl who suffered graft failure and hepatopulmonary syndrome following split liver retransplantation with endovascular stenting of the hepatic and portal veins as an infant. She was diagnosed with biliary atresia-polysplenia syndrome, and thus underwent living donor liver transplantation from her mother at 9 months of age. The first liver graft failed due to stenosis of the portal vein. She underwent the second liver transplantation with a split left lateral section graft. Endovascular stenting was performed to the portal vein stenosis 2 months and hepatic vein stenosis 9 months after transplantation. During the next 9 years, 11 sessions of balloon angioplasty for hepatic vein stent stenosis were performed. Ten years after the second transplantation, she underwent third transplantation using a whole liver graft recovered from a 12-year-old-girl. The double inferior vena cava technique was used for outflow vein reconstruction. The graft portal vein was anastomosed with the stent-containing portal vein stump because it was not possible to remove the stent and the inner diameter of the portal vein stent was large enough. An aorto-hepatic jump graft was used for arterial reconstruction. The patient recovered slowly and is doing well for 6 months posttransplant. In conclusion, because stenting of the hepatic vein or portal vein can induce graft failure leading to late retransplantation, we emphasize secure vascular reconstruction to prevent endovascular stenting during LT in infants.

Liver Transplantation in Children: An Overview of Organ Allocation and Surgical Management

Liver transplantation is the standard treatment for children with end-stage liver disease, primary hepatic neoplasms, or liver-localized metabolic defects. Perioperative mortality is almost absent, and long-term survival exceeds 90%. Organ shortage is managed thanks to advances in organ retrieval techniques; living donation and partial liver transplantation almost eliminated waiting list mortality, thus leading to expanding indications for transplantation. The success of pediatric liver transplantation depends on the prompt and early referral of patients to transplant Centers and on the close and integrated multidisciplinary collaboration between pediatricians, hepatologists, surgeons, intensivists, oncologists, pathologists, coordinating nurses, psychologists, and social workers.

Graft outflow vein venoplasty for a laparoscopically harvested left lateral section graft in pediatric living donor liver transplantation

Laparoscopically harvested left lateral section (LLS) grafts have drawbacks regarding the size of the graft left hepatic vein (LHV) orifice although they have the merit of cosmetics concerning the donor’s wound. We present a case of pediatric living donor liver transplantation (LDLT) using a laparoscopically harvested LLS graft and describe the refined surgical techniques for graft LHV venoplasty with a circumferential vein patch. The patient was a 46-month-old boy with marked growth retardation who was diagnosed with progressive familial intrahepatic cholestasis type 2. The donor was his 25-year-old mother. The LLS graft weighed 285 g. A circumferential patch of external iliac vein homograft was attached to the graft LHV orifice after incisions were made at the medial wall of the LHV trunk and superficial LHV branch, which made the graft LHV orifice much larger. The recipient’s hepatic vein orifice was also enlarged by unifying the three hepatic vein orifices. Other surgical procedures followed the standard LDLT operation. This patient recovered uneventfully and has been doing well for 1 year. In conclusion, our incision-and-patch venoplasty to enlarge the graft outflow vein orifice was beneficial for reducing the risk of hepatic vein outflow obstruction in LDLT using a laparoscopically harvested LLS graft.

Graft outflow vein unification venoplasty with superficial left hepatic vein branch in pediatric living donor liver transplantation using a left lateral section graft

Orifice size of the left hepatic vein trunk (LHV) in left lateral segment (LLS) grafts is often too small to perform direct anastomosis. A small superficial branch of LHV is encountered in approximately 30% of LLS grafts. Unification venoplasty of the LHV trunk and its superficial vein branch makes the orifice size of LLS outflow vein larger than the original size. We present refined surgical techniques for LHV unification venoplasty with a superficial LHV branch. The patient was a 5-month-old 9 kg-weighing girl with biliary atresia. Her general condition deteriorated, but there was low possibility of deceased donor liver allocation, thus living donor liver transplantation was performed using her mother's LLS. The graft hepatic vein was widened through unification venoplasty of LHV and its superficial branch. Recipient hepatic vein orifice was widened through unification of three hepatic veins. The graft and recipient hepatic vein orifices were well matched in size, and they were anastomosed with 5-0 continuous sutures. The portal vein was reconstructed with interposition of cold-preserved external iliac vein homograft. The graft left hepatic artery was reconstructed using the recipient right hepatic artery and hepaticojejunostomy was performed. This patient recovered uneventfully and is doing well for 3 months to date. The unification venoplasty with LHV trunk and its superficial vein branch makes the size of LLS outflow vein definitely larger than the original size, thus it can be a useful technical option to reduce the risk of hepatic vein outflow obstruction in pediatric liver transplantation using a LLS graft.

The devil is in the detail: current management of perioperative surgical complications after liver transplantation

PURPOSE OF REVIEW

Despite advances in the field, perioperative morbidity is common after liver transplantation. This review examines the current literature to provide up-to-date management of common surgical complications associated with liver transplantation.

RECENT FINDINGS

Research focuses on problems with anastomoses of the vena cava, portal vein, hepatic artery, and bile ducts. Interventional endoscopic and radiological techniques are used more frequently to avoid reoperation.

SUMMARY

Advances in the management of perioperative surgical complications have focused on minimally invasive measures that successfully treat technical problems with implantation of liver allografts from both living and deceased donors.