HEPATIC ALLOGRAFT ARTERIALIZATION BY MEANS OF THE GASTRODUODENAL BIFURCATION (BRANCH PATCH) AS A PROGNOSTIC FACTOR

Donor-recipient human leukocyte antigen A mismatching is associated with hepatic artery thrombosis, sepsis, graft loss, and reduced survival after liver transplant

Human leukocyte antigen (HLA) matching is not routinely performed for liver transplantation as there is no consistent evidence of benefit; however, the impact of HLA mismatching remains uncertain. We explored the effect of class I and II HLA mismatching on graft failure and mortality. A total of 1042 liver transplants performed at a single center between 1999 and 2016 with available HLA typing data were included. The median follow-up period was 9.38 years (interquartile range 4.9-14) and 350/1042 (33.6%) transplants resulted in graft loss and 280/1042 (26.9%) in death. Graft loss and mortality were not associated with the overall number of mismatches at HLA-A, HLA-B, HLA-C, HLA-DR, and HLA-DQ loci. However, graft failure and mortality were both increased in HLA mismatching on graft failure and mortality the presence of one (p = 0.004 and p = 0.01, respectively) and two (p = 0.01 and p = 0.04, respectively) HLA-A mismatches. Elevated hazard ratios for graft failure and death were observed with HLA-A mismatches in univariate and multivariate Cox proportional hazard models. Excess graft loss with HLA-A mismatch (138/940 [14.7%] mismatched compared with 6/102 [5.9%] matched transplants) occurred within the first year following transplantation (odds ratio 2.75; p = 0.02). Strikingly, transplants performed at a single all grafts lost due to hepatic artery thrombosis were in HLA-A-mismatched transplants (31/940 vs. 0/102), as were those lost due to sepsis (35/940 vs. 0/102). In conclusion, HLA-A mismatching was associated with increased graft loss and mortality. The poorer outcome for the HLA-mismatched group was due to hepatic artery thrombosis and sepsis, and these complications occurred exclusively with HLA-A-mismatched transplants. These data suggest that HLA-A mismatching is important for outcomes following liver transplant. Therefore, knowledge of HLA-A matching status may potentially allow for enhanced surveillance, clinical interventions in high-risk transplants or stratified HLA-A matching in high-risk recipients.

Impact of Hepatic Artery Variations and Reconstructions on the Outcome of Orthotopic Liver Transplantation

BACKGROUND

Donor variational arteries often require complex reconstruction.

METHODS

We analysed the incidence of different variations, types of arterial reconstructions and their impact on post-operative results from 409 patients undergoing liver transplantation at Karolinska Institute between 2007 and 2015.

RESULTS

A total of 292 (71.4%) liver grafts had a standard hepatic artery (SHA), and 117 (28.6%) showed hepatic artery variants (HAV). 58% of HAV needed reconstruction. The main variations were variant left hepatic artery (45.3%) from the gastric artery; variant right hepatic artery (38.5%); and a triple combination of variant right and left hepatic artery and the proper hepatic artery from the common hepatic artery (12.8%); other 3.4%. Patients/graft survival and arterial complications were not different between SHA and HAV. Incidence of biliary stricture was numerically higher in left hepatic artery variants (p = 0.058) and in variants where no arterial reconstruction was performed (p = 0.001). Operation and arterial warm ischaemia time were longer in the HAV group. The need for intraoperative re-reconstruction was higher in the HAV group (p = 0.04). Intraoperative bleeding was larger after back-table reconstruction than with intraoperative reconstruction (p = 0.04).

CONCLUSION

No overall differences were found between the HAV and the SHA groups. Occurrence of a variant left hepatic artery and HAV with no reconstruction seems to increase the risk of biliary strictures.

Impact of ABO-incompatibility on hepatic artery thrombosis in living donor liver transplantation

Background

The current era of rituximab-based regimens brought improved survival in ABO-incompatible (ABO-I) living donor liver transplantation (LDLT). Nevertheless, the actual risk for hepatic artery thrombosis (HAT) still remains to be investigated. The aim of this study was to evaluate the impact of ABO-incompatibility on HAT in adult LDLT patients.

Methods

Patients who received ABO-I LDLT were compared to those who received ABO-compatible (ABO-C) LDLT with a special focus on HAT.

Results

A total of 378 patients underwent LDLT from January 2012 to February 2018. Of those, ABO-I LDLT was performed in 78 consecutive patients. The other 300 patients with ABO-C LDLT constituted the comparator group. No significant differences were observed between the two groups in baseline and perioperative characteristics. HAT occurred in 11 (2.9%) patients, 2 and 9 patients in ABO-I and ABO-C LDLT groups, respectively, which didn't show any significant difference between the two groups (P=0.84). All were categorized into early HAT. Immediate revascularization by intraarterial thrombolysis was successfully employed in 8 patients. Surgical revision of anastomosis and retransplantation were performed in 1 and 2 patients, respectively. No one-year mortality was related to HAT in the two groups. The overall outcomes including biliary complications made no significant difference between the two groups.

Conclusions

ABO-incompatibility has no adverse impact on the incidence and treatment outcome of HAT in the current rituximab-based desensitization.

Dorsal approach plus branch patch technique is the preferred method for liver transplanting small babies with monosegmental grafts

PURPOSE

When living donor liver transplantation (LDLT) is performed on small infant patients, the incidence of hepatic artery complications (HACs) is high. Here, we present a retrospective analysis that focuses on our surgical procedure for hepatic arterial reconstruction and the outcomes of monosegmental LDLT.

METHODS

Of the 275 patients who underwent LDLT between May 2001 and December 2015, 13 patients (4.7 %) underwent monosegmental LDLT. Hepatic artery reconstruction was performed under a microscope. The size discrepancy between the graft and the recipient's abdominal cavity was defined as the graft to recipient distance ratio (GRDR) between the left hepatic vein and the portal vein (PV) bifurcation on a preoperative computed tomography scan. HACs were defined as hepatic arterial hypoperfusion.

RESULTS

Recipient hepatic arteries were selected for the branch patch technique in five cases (38.5 %), and the diameter was 2.2 ± 0.6 mm. The anastomotic approaches selected were the dorsal position of the PV in seven cases (53.8 %) and the ventral position in six, and the GRDRs were 2.8 ± 0.4 and 1.9 ± 0.5, respectively (p = 0.012). The incidence rate of HACs caused by external factors, such as compression or inflammation around the anastomotic site, was significantly higher in monosegmental than in non-monosegmental graft recipients (15.4 vs. 1.1 %, p < 0.001).

CONCLUSION

Although monosegmental graft recipients experienced HACs caused by external factors around the anastomotic field, hepatic arterial reconstruction could be safely performed. Important components of successful hepatic arterial reconstructions include the employment of the branch patch technique and the selection of the dorsal approach.

Direct pressure measurement in the hepatic artery during liver transplantation: can it prevent the "steal" syndrome?

Splenic artery "steal" syndrome after orthotopic liver transplantation (OLT) is an important cause of graft dysfunction. Direct pressure measurement in the hepatic (HA) and radial artery (RA) may identify patients at risk allowing its prevention. This observational study compared radial and hepatic mean arterial pressures (MAP) measured during 100 OLTs performed in 99 recipients, in whom the HA was considered suitable for the anastomosis. A difference of ≥5 mmHg between the radial and hepatic MAP was arbitrarily chosen as the criterion for inflow modulation. Seven patients fulfilled this criterion showing a MAP gradient that was significantly different compared to the others (-10.8±3.3 vs. 2.6±5.0; p<0.0001). They underwent splenic artery ligation (n=5), arcuate ligament division (n=1) and aortohepatic bypass grafting (n=1) that all resulted in immediate normalization of the arterial inflow pressure to the graft. The splenic artery "steal" syndrome occurred in one patient (day 2 after OLT) in whom the mean HA pressure normalized during OLT following arcuate ligament division, suggesting pathology within the graft as the most likely etiology. Our results indicate that radial MAP can reflect the hepatic MAP during OLT. If a substantial pressure gradient is found, it can be corrected by intraoperative splenic artery ligation or arcuate ligament division.

The technique and outcomes of branch-patch arterial reconstruction in living donor liver transplantation

BACKGROUND

Although living donor liver transplantation (LDLT) is now an established therapeutic modality for end-stage liver disease, technical dilemmas exist. The pretransplant imaging findings may not clearly define the surgical anatomy of the hepatic artery (HA), especially its diameter. A tiny artery (<2 mm) has always been found during the hilar dissection. Its size is discrepant to the diameter to the recipient arterial stump. The aim of this paper was to report a hepatic arterial reconstruction technique for small diameter (<2 mm) vessels in a partial liver graft.

METHODS

Since January 2002 to May 2007, we performed 9 LDLT with small hepatic arteries (<2 mm), which were analyzed retrospectively for this report. In this technique, we transect the donor hepatic artery proximally and distally to the tiny graft artery, take off and create a patch for arterial anastomosis. Computed tomographic angiography is used to evaluate the vascular anatomy and to measure the diameter of the graft HAs.

RESULTS

All donors were discharged without any vascular complications. One donor experienced a bile leakage from the dissections plane of the liver, which was treated by draining the abdominal cavity. Eight of the 9 patients survived without evidence of hepatic artery thrombosis during 32 months (range, 14-72); one subject died due to cytomegalovirus infection.

CONCLUSION

The arterial reconstruction technique enabled use of tiny arteries, eliminating the problems of diameter discrepancy without increasing donor complications.

Feasibility and effectiveness of a new algorithm in preventing hepatic artery thrombosis after liver transplantation

INTRODUCTION

The incidence of hepatic artery thrombosis (HAT) after liver transplantation (LTx) is up to 9% in adult recipients.

MATERIAL AND METHODS

To minimize HAT, we developed an algorithm that we have routinely applied since 2001. The algorithm is a cascade of potentially necessary procedures to improve hepatic artery blood flow before proceeding with LTx when arterial blood flow is impaired. Incidence, outcome, and possible therapeutic approaches of HAT were analyzed in prospectively non-controlled collected data during a 5-year period. There were 335 LTx in 299 adults (199 male, 100 female) with a median age of 49.7 years.

RESULTS

HAT was defined as early and late HAT (diagnosis within or after 30 days following LTx). After a mean follow-up of 17 months, nine HAT were documented (2.7%; five early and four late HAT). Treatment consisted of thrombolysis (n = 1), surgical thrombectomy (n = 4), and re-transplantation (n = 4). Five HAT patients died during follow-up.

DISCUSSION

Complex arterial reconstruction was associated with HAT compared to branch-patch anastomoses (P = 0.0193). Median arterial intraoperative blood flow was no risk factor for HAT. One-year patient survival after HAT was 31%. Once HAT occurs, complication rates are high and long-term results are devastating.

CONCLUSION

Therefore, we have implemented the presented algorithm, which showed an acceptable HAT rate.

Early hepatic artery thrombosis after liver transplantation: a systematic review of the incidence, outcome and risk factors

To clarify inconsistencies in the literature we performed a systematic review to identify the incidence, risk factors and outcome of early hepatic artery thrombosis (eHAT) after liver transplantation. We searched studies identified from databases (MEDLINE, EMBASE, Science Citation Index) and references of identified studies. Seventy-one studies out of 999 screened abstracts were eligible for this systematic review. The incidence of eHAT was 4.4% (843/21, 822); in children 8.3% and 2.9% in adults (p < 0.001). Doppler ultrasound screening (DUS) protocols varied from 'no routine' to 'three times a day.' The median time to detection was at day seven. The overall retransplantation rate was 53.1% and was higher in children (61.9%) than in adults (50%, p < 0.03). The overall mortality rate of patients with eHAT was 33.3% (range: 0-80%). Mortality in adults (34.3%) was higher than in children (25%, p < 0.03). The reported risk factors for eHAT were, cytomegalovirus mismatch (seropositive donor liver in seronegative recipient), retransplantation, arterial conduits, prolonged operation time, low recipient weight, variant arterial anatomy, and low volume transplantation centers. eHAT is associated with significant graft loss and mortality. Uniform definitions of eHAT and uniform treatment modalities are obligatory to confirm these results and to obtain a better understanding of this disastrous complication.

[Orthotopic liver transplantation. Techniques and results]

Since 1963, orthotopic liver transplantation (OLT) has developed into an established interdisciplinary therapy concept for patients with end-stage liver disease, acute irreversible liver failure, and hepatic malignancies in selected cases. In 26 centers in Germany, around 900 full-size OLTs are performed annually. The classic technique has been replaced by the "piggyback" method, which has become the standard in many centres. Improvements in surgical techniques, anaesthetic protocols, and medical management along with the introduction of new immunosuppressive regimens and early adequate therapy against infections and transplant rejection have increased patient survival. These factors have resulted in 1-year survival rates of 80-90% and led to an increase in indications for OLT. Despite decades of experience, approximately 10% of the mortality in the first 3 months still can be traced to technical complications.

How to increase inflow in liver transplantation

Liver transplantation (LTx) has become the treatment of choice for selected cases of benign and malignant liver disease. Despite becoming increasingly safer in recent years this procedure still incurs several serious postoperative complications. The most significant surgical complications are related to surgical technique, particularly the reconstruction and/or anastomosis of the hepatic artery. Arterial hypoperfusion may lead to graft failure, sepsis, or ischemic biliary lesions. In this review we focus on the Achilles' heel of LTx: the hepatic artery. We provide transplant surgeons with an overview of the technical options that are available to increase arterial inflow and subsequently improve patient outcome. We exemplify some of the discussed techniques using a liver transplant case with an eventful postoperative course because of arterial complications.

Branch patch reconstruction in living donor liver transplantation: arterialization of grafts with replaced type arteries

We developed a hepatic arterialization technique in living donor liver transplantation. The technique was indicated in patients with a left graft from donors with a right hepatic artery originated from superior mesenteric artery or a right graft from donors with a left hepatic artery from left gastric artery. The donor common hepatic and gastroduodenal arteries were split. On the recipient side, left and right hepatic arteries or branches of the right hepatic artery were split, received patch plasty, and anastomosed with the graft arteries under loupe observation. Livers from 25 donors were procured (16 right livers and 9 left livers) using this technique. There were no vascular complications in the donors. Three recipients died due to infectious disease with arterial patency. The remaining 22 recipients survived without hepatic arterial thrombosis. In limited situations, this technique can be adapted for living donor liver transplantation without increasing donor complications.