Early hepatic artery thrombosis treatments and outcomes: aorto-hepatic arterial conduit interposition or revision of anastomosis?

BACKGROUND: Hepatic artery thrombosis (HAT) is one of the critical conditions after an orthotopic liver transplant (OLT) and leads to severe problems if not corrected promptly. However, multiple treatments have been proposed for HAT, in which surgical revascularization with either auto-hepatic conduit interposition (AHCI) or revision of the anastomosis is more familiar indeed indicated for some patients and in specific situations. In this study, we want to evaluate the success and outcomes of treating early HAT (E-HAT), which defines HAT within 30 days after OLT with either of the surgical revascularization techniques. METHOD: In this retrospective study, we collected information from the medical records of patients who underwent either of the surgical revascularization procedures for E-HAT after OLT. Patients who needed early retransplantation (RT) or died without surgical intervention for E-HAT were excluded. Demographic data, OLT surgery information, and data regarding E-HAT were gathered. The study outcomes were secondary management for E-HAT in case of improper inflow, biliary complications (BC), RT, and death. RESULTS: A total of 37 adult patients with E-HAT after OLT included in this study. These E-HATs were diagnosed within a mean of 4.6 ± 3.6 days after OLT. Two patients had their HA revised for the initial management of E-HAT; however, it changed to AHCI intraoperatively and finally needed RT. Two and nine patients from the AHCI and revision groups had re-thrombosis (12.5% vs. 47.3%, respectively, p = 0.03). RT was used to manage rethrombosis in all patients of AHCI and two patients of the revision group (22.2%). In comparison to the AHCI, revision group had statistically insignificant higher rates of BC (47.4% vs. 31.2%); however, RT for nonvascular etiologies (12.5% vs. 5.3%) and death (12.5% vs. 10.5%) were nonsignificantly higher in AHCI group. All patients with more than one HA exploration who were in the revision group had BC; however, 28.5% of patients with just one HA exploration experienced BC (p < 0.001). CONCLUSION: Arterial conduit interposition seems a better approach for the initial management of E-HAT in comparison to revision of the HA anastomosis due to the lower risk of re-thrombosis and the number of HA explorations; indeed, BC, RT, and death remain because they are somewhat related to the ischemic event of E-HAT than to a surgical treatment itself.

Utilization and outcomes of rescue hepatectomy among U.S. liver retransplant candidates.

INTRODUCTION: The frequency and outcomes of anhepatic patients listed for transplantation in the United States have not been studied. The United Network for Organ Sharing (UNOS) records anhepatic status for patients listed as Status 1A for hepatic artery thrombosis (HAT) or primary non-function (PNF). METHODS: Using the UNOS database from 2005 to 2020, demographics and waitlist outcomes of anhepatic candidates relisted as Status 1A for HAT or PNF were assessed. RESULTS: Among 1364 adult Status 1A patients relisted for PNF or HAT across 120 distinct transplant centres, 75 (5.5%) patients were anhepatic and 1289 (94.5%) were non-anhepatic. A substantial number of centres (n = 51) had experience with ≥1 anhepatic patient relisted for either PNF or HAT, with individual centre rates ranging from 0% to 11.4%. Waitlist mortality was more than twice as high for anhepatic patients: 42.5% versus 17.0% non-anhepatic patients (p < .001). The post-transplant outcomes of anhepatic patients were markedly inferior to non-anhepatic patients. For example, 41.9% of anhepatic patients died during the index admission versus 23.4% of the non-anhepatic group (p = .006). Patient survival for the anhepatic and non-anhepatic groups was 48.3% versus 66.2% at 1-year and 29.3% versus 46.2% at 5-years, respectively (log-rank test for overall survival p = .014). CONCLUSIONS: Rescue hepatectomy after initial liver transplantation is not only associated with high waitlist mortality, but also markedly worse post-transplant outcomes. With less than half of anhepatic patients surviving to the first year post-LT, further research is warranted to better delineate which patients should be considered for rescue hepatectomy.

Pyogenic liver abscesses in liver transplant recipients versus non-transplant population. Outcome and risk factors of patient survival.

Pyogenic liver abscess (PLA) is a life-threatening infection in both liver transplant (LT) and non-LT patients. Several risk factors, such as benign and malignant hepatopancreatobiliary diseases and colorectal tumors have been associated with PLA in the non-LT population, and hepatic artery stricture/thrombosis, biliary stricture, and hepaticojejunostomy in the LT patients. The objective of this study is to compare the outcomes of patients with PLA in LT and non-LT patients and to determine the risk factors associated with patient survival. From January 2000 to November 2020, a total of 296 adult patients were diagnosed of PLA in our institution, of whom 26 patients had previously undergone liver transplantation (LTA group), whereas 263 patients corresponded to the non-LTA population. Seven patients with PLA who had undergone previous kidney transplantation were excluded from this retrospective study. Twenty-six patients out of 1503 LT developed PLA (incidence of 1.7%). Median age was significantly higher in non-LTA patients (p = .001). No significant differences were observed in therapy. PLA recurrence was significantly higher in LTA than in non-LTA (34.6% vs. 14.8%; p = .008). In-hospital mortality was greater in the LT group than in the non-LT group (19.2% vs. 9.1% p = .10) and was identified in multivariable analysis as a risk factor for mortality (p = .027). Mortality rate during follow-up did not show significant differences between the groups: 34.6% in LTA patients versus 26.2% in non-LTA patients (p = .10). The most common causes of mortality during follow-up were malignancies, Covid-19 infection, and neurologic disease. 1-, 3-, and 5-year actuarial patient survival rates were 87.0%, 64.1%, and 50.4%, respectively, in patients of LTA group, and 84.5%, 66.5%, and 51.0%, respectively, in patients with liver abscesses in non-LTA population (p = .53). In conclusion, LT was a risk factor for in hospital mortality, but not during long-term follow-up.

Diagnostic performance of contrast-enhanced ultrasound in diagnosing hepatic artery occlusion after liver transplantation: A systematic review and meta-analysis.

INTRODUCTION: Hepatic artery occlusion (HAO) is a significant complication post-liver transplantation. Doppler ultrasound (DUS) has been widely used as an initial screening test for detecting HAO; however, its performance is often not sufficient. Although other diagnostic tests such as computed tomography angiography (CTA), magnetic resonance angiography (MRA), and angiogram are more accurate, they are invasive and have several limitations. Contrast-enhanced ultrasound (CEUS) is an emerging tool for detecting HAO; however, the results from previous studies were limited due to a small number of patients. Therefore, we aimed to evaluate its performance by performing a meta-analysis. METHOD: We performed a systemic review and meta-analysis of studies evaluating the performance of CEUS for the detection of HAO in an adult population. A literature search of EMBASE, Scopus, CINAHL, and Medline was conducted through March 2022. Pooled sensitivity, specificity, log diagnostic odd ratio (LDOR), and area under summary receiver operating curve (AUC) were calculated. Publication bias was assessed by Deeks' funnel plot. RESULT: Eight studies were included, with 434 CEUS performed. Using a combination of CTA, MRA, angiography, clinical follow-up, and surgery as the gold standard, the sensitivity, specificity, and LDOR of CEUS for detection of HAO were .969 (.938, .996), .991 (.981, 1.001), and 5.732 (4.539, 6.926), respectively. AUC was .959. The heterogeneity between studies appeared universally low, and no significant publication bias was found (p = .44). CONCLUSION: CEUS appeared to have an excellent performance for the detection of HAO and could be considered as an alternative when DUS is non-diagnostic or when CTA, MRA, and angiogram are not feasible.

Safety and efficacy of everolimus initiation from the first month after liver transplantation: A systematic review and meta-analysis.

INTRODUCTION: Everolimus, a selective inhibitor of mamalian target of rapamycin (mTORi), is considered to be an alternative immunosuppressive regimen in the liver transplantation (LT) setting. However, most of the transplant centers avoid its early use (i.e., during the first month) after LT mainly due to safety issues. METHODS: We searched for all articles published between 01/2010 and 7/2022 to evaluate the effectiveness and safety of initial/early administration of everolimus after LT. RESULTS: Seven studies (three randomized controlled trials and four prospective cohort studies) were included: initial/early everolimus-including therapy (group 1) was used in 512 (51%) and calcineurin inhibitor (CNI) based therapy (group 2) in 494 (49%) patients. No significant difference was found between group 1 and group 2 patients regarding the rates of biopsy-proven acute rejection episodes (Odds Ratio [OR]: 1.27, 95% CI: .67-2.41, p = .465) and hepatic artery thrombosis (OR: .43, 95% CI: .09-2.02, p = .289). Everolimus was associated with higher rates of dyslipidemia (14.2% vs. 6.8%, p = .005) and incisional hernia (29.2% vs. 10.1%, p < .001). Finally, no difference was found between the two groups regarding recurrence of hepatocellular carcinoma (Risk Rates [RR]: 1.22 95%CI: .66-2.29, p = .524) and mortality (RR: .85 95%CI: .48-1.50, p = .570). CONCLUSION: Use of initial/early everolimus seems to be effective with a satisfactory safety profile, making its administration a reasonable therapeutic option in the LT setting.

The Yield of Routine Post-Operative Doppler Ultrasound to Detect Early Post-Liver Transplantation Vascular Complications.

Early detection of liver transplantation (LT) vascular complications enables timely management. Our aim was to assess if routine Doppler ultrasound (rDUS) improves the detection of hepatic artery thrombosis (HAT), portal vein thrombosis (PVT) and hepatic venous outflow obstruction (HVOO). We retrospectively analysed timing and outcomes, number needed to diagnose one complication (NND) and positive predictive value (PPV) of rDUS on post-operative day (POD) 0,1 and 7 in 708 adult patients who underwent primary LT between 2010-2022. We showed that HAT developed in 7.1%, PVT in 8.2% and HVOO in 3.1% of patients. Most early complications were diagnosed on POD 0 (26.9%), 1 (17.3%) and 5 (17.3%). rDUS correctly detected 21 out of 26 vascular events during the protocol days. PPV of rDUS was 53.8%, detection rate 1.1% and NND was 90.5. Median time to diagnosis was 4 days for HAT and 47 days for PVT and 21 days for HVOO. After intervention, liver grafts were preserved in 57.1%. In conclusion, rDUS protocol helps to detect first week's vascular events, but with low PPV and a high number of ultrasounds needed.

Favorable experience of transplant strategy including liver grafts from COVID-19 donors: One-year follow-up results.

BACKGROUND: Since November 2020, Italy was the first country to carry out a protocol and use liver from COVID-19 donors. We aimed to evaluate the medium-term outcome of patients who underwent liver transplant (LT) with those grafts. METHODS: We consecutively enrolled 283 patients who underwent first LT from November 2020 to December 2022 in our Center (follow-up 468 days). Twenty-five of 283 (8.8%, study population) received a graft from donors with previous (4%) or active (96%) SARS-CoV-2 infection, and 258/283 (91.2%, control group) received a graft from COVID-19-negative donors. SARS-CoV-2-RNA was tested on graft tissue of COVID-19 donors and their recipients underwent weekly evaluation of SARS-CoV-2-RNA in nasal swabs for the first month after LT. RESULTS: One-year and 2-year patient survival was 88.5% and 88.5% in study group versus 94.5% and 93.5% in control group, respectively (p = .531). In study population there was no evidence of donor-recipient virus transmission, but three (12%) patients (vs. 7 [2.7%] of control group, p = .048) developed hepatic artery thrombosis (HAT): they were SARS-CoV-2-RNA negative at LT and 1/3 grafts tested SARS-CoV-2-RNA positive on liver tissue. COVID-19 donor was independently associated with HAT (odds ratio (OR) = 4.85, 95% confidence interval (CI) 1.10-19.15; p = .037). By comparing study population with control group, acute rejection and biliary complication rates were not significantly different (16% vs. 8.1%, p = .26; 16% vs. 16.3% p = .99, respectively). CONCLUSIONS: Our 1-year results of transplant strategy including liver grafts from COVID-19 donors were favorable. HAT was the only complication with significantly higher rate in patients transplanted with COVID-19 donors compared with control group.

Comparative analysis of whole vs. split liver transplantation in infants.

BACKGROUND: Liver transplantation (LT) in infants can be challenging due to their small size and small vasculature. Although both whole LT (WLT) and split LT (SLT) have been described in infants, the head-to-head comparison of these techniques in this population is sparse. METHODS: We retrospectively analyzed the records of all patients with age ≤1 year at Indiana University between 2016 and 2022. All SLT were left lateral segment grafts split in situ. RESULTS: A total of 24 infants were transplanted, with 11 SLT and 13 WLT. The median follow-up time was 52.1 months. Donor and recipient characteristics were comparable except for donor age (19 years vs. 2 years; p < .01) and weight (64 kg vs. 14.2 kg; p < .01). Early allograft dysfunction, primary nonfunction, and hepatic artery thrombosis developed more frequently in the WLT group. There were no biliary complications. There were two early deaths (2 and 4 days) in the WLT group. One-year graft survival (100% vs. 77%; p = .10) and patient survival (100% vs. 85%; p = .18) were numerically higher in the SLT group. CONCLUSIONS: SLT with LLS offers a safe and viable option for liver transplantation in infants and is associated with a trend toward superior outcomes. SLT should be considered as a strategy to reduce waitlist times for infants in the absence of small, deceased donors for WLT.

An appraisal of technical variant grafts compared to whole liver grafts in pediatric liver transplant recipients: Multicenter analysis from the SPLIT registry.

BACKGROUND: Shortages of liver allografts for children awaiting transplantation have led to high LT waitlist mortality. Prior studies have shown that usage of TVG can reduce waiting time and waitlist mortality, but their use is not universal. We sought to compare patient and graft survival between WLG and TVG and to identify potential associated risk factors in a contemporary pediatric LT cohort. METHODS: We performed a retrospective analysis of patient survival, graft survival, and biliary and vascular complications for LT recipients <18 years old entered into the Society of Pediatric Liver Transplantation prospective multicenter database. RESULTS: Of 1839 LT recipients, 1029 received a WLG and 810 received a TVG from either a LD or a DD. There was no difference in patient survival or graft survival by graft type. Three-year patient survival and graft survival were 96%, 93%, and 96%, and 95%, 89%, and 92% for TVG-LD, TVG-DD, and WLG, respectively. Biliary complications were more frequent in TVG. Hepatic artery thrombosis was more frequent in WLG. Multivariate analysis revealed primary diagnosis was the only significant predictor of patient survival. Predictors for graft survival included time-dependent development of biliary and vascular complications. CONCLUSIONS: There were no significant differences in patient and graft survival based on graft types in this North American multi-center pediatric cohort. Widespread routine use of TVG should be strongly encouraged to decrease mortality on the waitlist for pediatric LT candidates.

Low hepatic artery resistive index on Doppler ultrasound performed on the first post-liver transplant day is associated both with hepatic artery thrombosis and decreased graft survival.

PURPOSE: Although liver transplantation (LT) outcomes have improved significantly over the last decades, early vascular complications are still associated with elevated risks of graft failure. Doppler ultrasound (DUS) enables detection of vascular complications, provides hepatic artery Resistive Index (RI). The aim of our study was to evaluate the association of the RI parameters of DUS performed in the first post-transplant week with post-transplant outcomes. METHODS: All consecutive patients undergoing a first LT between 2001 and 2019 at a single center were included. Patients were divided into two groups: RI < 0.55 and RI ≥ 0.55. Patients were also divided according to the presence or absence of hepatic artery thrombosis (HAT). Graft survival was compared between groups. RESULTS: Overall, 338 patients were included. HAT occurred in 23 patients (6.8%), of which 7 were partial and 16, complete. Biliary complications were more common in patients with HAT (10 [43.5%]) vs. 38 [12.1%] [p < 0.001]). Graft survival was lower for patients with HAT (p = 0.047). Also, RI < 0.55 was associated with increased incidence of HAT (p < 0.001). Additionally, patients with RI < 0.55 on post-operative day 1 had decreased graft survival as compared to patients with RI > 0.55 (p = 0.041). RI on post-operative day 3 and 5 was not predictive of inferior graft outcomes. CONCLUSIONS: Intensive use of DUS in the early post-LT period offers the possibility of early diagnosis of vascular complications, guiding medical and surgical management of HAT. Additionally, according to our data, low RI (< 0.55) on the first postoperative day also is a predictor of HAT and decreased graft-survival.

Risk factors indicating the need for surgical therapy in patients with pyogenic liver abscesses.

BACKGROUND: Percutaneous drainage (PD) and antibiotics are the therapy of choice (non-surgical therapy [non-ST]) for pyogenic liver abscesses (PLA), reserving surgical therapy (ST) for PD failure. The aim of this retrospective study was to identify risk factors that indicate the need for ST. METHODS: We reviewed the medical charts of all of our institution's adult patients with a diagnosis of PLA between January 2000 and November 2020. A series of 296 patients with PLA was divided into two groups according to the therapy used: ST (n = 41 patients) and non-ST (n = 255). A comparison between groups was performed. RESULTS: The overall median age was 68 years. Demographics, clinical history, underlying pathology, and laboratory variables were similar in both groups, except for the duration of PLA symptoms < 10 days and leukocyte count which were significantly higher in the ST group. The in-hospital mortality rate in the ST group was 12.2% vs. 10.2% in the non-ST group (p = 0.783), with biliary sepsis and tumor-related abscesses as the most frequent causes of death. Hospital stay and PLA recurrence were statistically insignificant between groups. One-year actuarial patient survival was 80.2% in the ST group vs. 84.6% in the non-ST (p = 0.625) group. The presence of underlying biliary disease, intra-abdominal tumor, and duration of symptoms for less than 10 days on presentation comprised the risk factors that indicated the need to perform ST. CONCLUSIONS: There is little evidence regarding the decision to perform ST, but according to this study, the presence of underlying biliary disease or an intra-abdominal tumor and the duration of PLA symptoms < 10 days upon presentation are risk factors that should sway the surgeons to perform ST instead of PD.

Characteristics and Outcomes of Liver Transplantation Recipients after Tranexamic Acid Treatment and Platelet Transfusion: A Retrospective Single-Centre Experience.

Background and Objectives: Patients undergoing liver transplantation (LT) often require increased blood product transfusion due to pre-existing coagulopathy and intraoperative fibrinolysis. Strategies to minimise intraoperative bleeding and subsequent blood product requirements include platelet transfusion and tranexamic acid (TXA). Prophylactic TXA administration has been shown to reduce bleeding and blood product requirements intraoperatively. However, its clinical use is still debated. The aim of this study was to report on a single-centre practice and analyse clinical characteristics and outcomes of LT recipients according to intraoperative treatment of TXA or platelet transfusion. Materials and Methods: This was a retrospective observational cohort study in which we reviewed 162 patients' records. Characteristics, intraoperative requirement of blood products, postoperative development of thrombosis and outcomes were compared between patients without or with intraoperative TXA treatment and without or with platelet transfusion. Results: Intraoperative treatment of TXA and platelets was 53% and 57.40%, respectively. Patients who required intraoperative administration of TXA or platelet transfusion also required more transfusion of blood products. Neither TXA nor platelet transfusion were associated with increased postoperative development of hepatic artery and portal vein thrombosis, 90-day mortality or graft loss. There was a significant increase in the median length of intensive care unit (ICU) stay in those who received platelet transfusion only (2.00 vs. 3.00 days; p = 0.021). Time to extubate was significantly different in both those who required TXA and platelet transfusion intraoperatively. Conclusions: Our analysis indicates that LT recipients still required copious intraoperative transfusion of blood products, despite the use of intraoperative TXA and platelets. Our findings have important implications for current transfusion practice in LT recipients and may guide clinicians to act upon these findings, which will support global efforts to encourage a wider use of TXA to reduce transfusion requirements, including platelets.

Early thrombotic and hemorrhagic complications associated with a risk-adjusted postoperative anticoagulation protocol after pediatric liver transplantation.

BACKGROUND: Systemic anticoagulation after pediatric liver transplantation (pLT) is believed to reduce the incidence of vascular thrombosis, but it may also cause an increase in hemorrhagic complications. PROCEDURE: A 5-year retrospective review of pLT done at our institution was performed (2014-2018). The occurrence of early hemorrhagic and thrombotic complications was compared when using low-dose or high-dose anticoagulation after transplant (p < .05 considered significant). RESULTS: Sixty-nine patients received 73 transplants during the study period. Median age at transplant was 2.3 years (40 days to 18.5 years). Low-dose anticoagulation was utilized in 71% cases. Additionally, six patients were converted from low-dose to high-dose anticoagulation because of a thrombotic event or concerns for suboptimal vascular inflow. Postoperative anticoagulation was discontinued in 18 occurrences due to bleeding (low dose 19%, high dose 47% vs. low dose to high dose 17%, p = .085). Surgical take back for bleeding occurred in 17 occasions (low dose 13.5%, high dose 53% vs. low dose to high dose 33%, p = .005). The overall incidence of hepatic artery thrombosis (HAT) and portal vein thrombosis were each 5.5%, respectively. While patient survival was not statistically different between groups, graft survival was significantly lower in the high-dose group (low dose 93%, high dose 73% vs. low dose to high dose 100%, p = .046). However, graft losses from HAT were similar between groups (low dose 2%, high dose 7% vs. low dose to high dose 0%, p = .56). CONCLUSION: The use of a standardized risk-adjusted anticoagulation protocol after pLT is associated with a low occurrence of thrombotic and hemorrhagic complications. High-dose anticoagulation leads to more bleeding, but those risks outweigh the risks of possible graft loss.

Effect of magnification in pediatric liver transplantation: A systematic review and meta-analysis.

BACKGROUND: Hepatic artery thrombosis (HAT) represents a devastating and often fatal complication of liver transplantation. Due to the small vessel caliber in pediatric patients, the use of an operating microscope has largely become the standard for hepatic artery reconstruction to reduce the rate of HAT. Recent evidence, however, suggests that loupe magnification for anastomosis may be equally effective. We aimed to determine the effect of magnification on the rate of hepatic artery thrombosis in pediatric liver transplantation. METHODS: A systematic search of the literature was conducted. Thousand eighty-eight unique titles were assessed by two independent reviewers. Studies directly comparing rates of HAT from loupe magnification and operating microscope-assisted anastomoses were eligible for meta-analysis. RESULTS: Among primary transplants, the rate of HAT was 6.0%. Operating microscope anastomosis was associated with a 2.6% decrease in the rate of HAT compared to that of loupe magnification (4.9% and 7.4%, respectively, p < .040). When re-transplants were included, the rate of HAT was 5.8%. Operating microscope anastomosis was associated with a 1.0% decrease in the rate of HAT compared to that of loupe magnification (5.3% and 6.3%, respectively, p < .279). Meta-analysis of eligible studies demonstrated a reduction in the rate of HAT with the use of an operating microscope (p < .03). CONCLUSIONS: Anastomosis under an operating microscope may be associated with decreased rates of HAT in children undergoing primary liver transplantation. Further high-quality studies comparing the two techniques are needed.

Hepatic artery reconstruction using an operating microscope in pediatric liver transplantation-Is it worth the effort?

INTRODUCTION: In pediatric liver transplantation (pLT), hepatic artery thrombosis (HAT) is associated with inferior transplant outcome. Hepatic artery reconstruction (HAR) using an operating microscope (OM) is considered to reduce the incidence of HAT. METHODS: HAR using an OM was compared to a historic cohort using surgical loupes (SL) in pLT performed between 2009 and 2020. Primary endpoint was the occurrence of HAT. Secondary endpoints were 1-year patient and graft survival determined by Kaplan-Meier analysis and complications. Multivariate analysis was used to identify independent risk factors for HAT and adverse events. RESULTS: A total of 79 pLTs were performed [30 (38.0%) living donations; 49 (62.0%) postmortem donations] divided into 23 (29.1%) segment 2/3, 32 (40.5%) left lobe, 4 (5.1%) extended right lobe, and 20 (25.3%) full-size grafts. One-year patient and graft survival were both 95.2% in the OM group versus 86.2% and 77.8% in the SL group (p = .276 and p = .077). HAT rate was 0% in the OM group versus 24.1% in the SL group (p = .013). One-year patient and graft survival were 64.3% and 35.7% in patient with HAT, compared to 93.9% and 92.8% in patients with no HAT (both p < .001). Multivariate analysis revealed HAR with SL (p = .022) and deceased donor liver transplantation (DDLT) (p = .014) as independent risk factors for HAT. The occurrence of HAT was independently associated with the need for retransplantation (p < .001) and biliary leakage (p = .045). CONCLUSION: In pLT, the use of an OM is significantly associated to reduce HAT rate, biliary complications, and graft loss and outweighs the disadvantages of delayed arterial perfusion and prolonged warm ischemia time (WIT).

Our evolution in the treatment of hepatic artery and portal vein thrombosis in pediatric liver transplantation: Success with catheter-directed therapies.

BACKGROUND: In pediatric liver transplant recipients, hepatic artery thrombosis and portal vein thrombosis are major causes of acute graft failure and mortality within 30 days of transplantation. There is, however, a strong possibility of graft salvage if flow can be re-established to reduce ischemic injury. The current standard treatment is surgical revascularization, and if unsuccessful, retransplantation. Due to our success in treating these complications with catheter-directed therapies, we sought to summarize and publish the outcomes of all patients who experienced hepatic artery thrombosis or portal vein thrombosis within 30 days of liver transplantation. METHODS: We conducted a retrospective cohort analysis of 27 pediatric liver transplant recipients who experienced hepatic artery thrombosis (n = 13), portal vein thrombosis (n = 9), or both (n = 5) between September 2012 and March 2021. We collected and tabulated data on the patients and therapies performed to treat them, including success rates, primary and secondary patency, and clinical outcomes. RESULTS: Among these patients, 6 were managed with anticoagulation and relisting for transplant and 21 had a primary revascularization attempt. Surgical recanalization was attempted in 7 patients of which 3 had successful recanalization (43%) and catheter-directed recanalization was attempted in 14 patients with 100% success in re-establishing blood flow to the graft. Additionally, patency was increased, and mortality was decreased in patients treated with catheter-directed recanalization compared to surgical revascularization or anticoagulation alone. CONCLUSION: This data illustrates the need to further investigate catheter-directed thrombolysis as a potential first-line treatment for postoperative HAT and PVT in pediatric liver transplant recipients.

Microsurgical replacement of the right hepatic artery with the donor superior mesenteric artery in cadaveric donor pediatric liver transplantation.

PURPOSE: To present our experience of using the pediatric donor superior mesenteric artery (SMA) as the interpositioning vessel to reconstruct the hepatic artery in pediatric deceased donor liver transplantation. METHODS: Pediatric patients who received pediatric deceased donor livers from December 2019 to June 2021 were enrolled. RESULTS: A total of 43 pediatric recipients received pediatric deceased donor livers during the study period. Thirty-four (79.1%) pediatric donors had normal hepatic artery anatomy, while nine (20.9%) showed variant anatomies. The SMAs of the pediatric donors were interposed in the latter eight cases. The anastomosis between the donor distal SMA and the donor celiac trunk artery (CTA) was initially performed in the back-table period, after which the other anastomosis between the donor proximal SMA and recipient CHA was performed. Only one case showed HAT occurrence (incidence rate, 2.3%). However, no arterial complications occurred in pediatric recipients with donor grafts that showed the variation of RHA replacement from the SMA and had undergone usage of the donor's SMA as an interpositioning vessel. CONCLUSIONS: In pediatric deceased donor liver transplantation, the use of SMA as an interpositioning medium can solve the problems related to a tiny caliber and anatomical variations of the donor hepatic artery.

Donor diabetes mellitus is a risk factor for diminished outcome after liver transplantation: a nationwide retrospective cohort study.

With the growing incidence of diabetes mellitus (DM), an increasing number of organ donors with DM can be expected. We sought to investigate the association between donor DM with early post-transplant outcomes. From a national cohort of adult liver transplant recipients (1996-2016), all recipients transplanted with a liver from a DM donor (n = 69) were matched 1:2 with recipients of livers from non-DM donors (n = 138). The primary end-point included early post-transplant outcome, such as the incidence of primary nonfunction (PNF), hepatic artery thrombosis (HAT), and 90-day graft survival. Cox regression analysis was used to analyze the impact of donor DM on graft failure. PNF was observed in 5.8% of grafts from DM donors versus 2.9% of non-DM donor grafts (P = 0.31). Recipients of grafts derived from DM donors had a higher incidence of HAT (8.7% vs. 2.2%, P = 0.03) and decreased 90-day graft survival (88.4% [70.9-91.1] vs. 96.4% [89.6-97.8], P = 0.03) compared to recipients of grafts from non-DM donors. The adjusted hazard ratio for donor DM on graft survival was 2.21 (1.08-4.53, P = 0.03). In conclusion, donor DM is associated with diminished outcome early after liver transplantation. The increased incidence of HAT after transplantation of livers from DM donors requires further research.

Management of early hepatic artery thrombosis following living-donor liver transplantation: feasibility, efficacy and potential risks of endovascular therapy in the first 48 hours post-transplant-a retrospective cohort study.

This retrospective cohort study aims to review our 18-year experience with early hepatic artery thrombosis (e-HAT) following living-donor liver transplantation (LDLT), as well as to assess the feasibility, efficacy and potential risks of endovascular management of e-HAT in the first 48 hours (hrs) post-LDLT. Medical records of 730 patients who underwent LDLT were retrospectively reviewed. In all cases who had developed e-HAT, treatment modalities employed and their outcomes were evaluated. Thirty-one patients developed e-HAT(4.2%). Definite technical success and 1-year survival rates of surgical revascularization[11/31 cases(35.5%)] were 72.7% & 72.7%, whereas those of endovascular therapy[27/31 cases(87.1%)] were 70.4% & 59.3%, respectively. Endovascular therapy was carried out in the first 48hrs post-transplant in 9/31 cases(29%) [definite technical success:88.9%, 1-year survival:55.6%]. Four procedure-related complications were reported in 3 of those 9 cases(33.3%). In conclusion, post-LDLT e-HAT can be treated by surgical revascularization or endovascular therapy, with comparable results. Endovascular management of e-HAT in the first 48hrs post-LDLT appears to be feasible and effective, but is associated with a relatively higher risk of procedure-related complications, compared to surgical revascularization. Hence, it can be reserved as a second-line therapeutic option in certain situations where surgical revascularization is considered futile, potentially too complex, or potentially more risky.

Early hepatic arterial thrombosis in liver transplantation: Systemic intravenous alteplase as a potential rescue treatment after failed surgical revascularization.

eHAT is one of the most dreaded post-LT complication. Treatment approaches include retransplantation, revascularization, or observation. Systemic thrombolytic therapy is used in pediatric patients with thromboembolic events. However, there is no previous study reporting on the use of systemic r-tPA to treat eHAT. The treatment strategies used in patients with eHAT are described, focusing on two children who failed SR and were treated with systemic heparinization plus systemic r-tPA infusion. r-tPA-RP consists of intravenous systemic infusion at a dose of 0.3 mg/kg/h during 6 hours, for 5 days. First case (3-year) was transplanted with a whole liver, and second case (6-year) received a LLS from a living donor. HAT was diagnosed by doppler US and confirmed by angioCT scan in both patients in the first day after LT. They underwent SR and were clinically stable. Re-thrombosis occurred in both patients the day after, and r-TPA-RP was started-one patient required two r-TPA-RP for HAT recurrence. They presented minor bleeding, without repercussion. Hepatic artery recanalized after 10 and 3 days in the first and second patient, respectively. Retransplant was avoided, and one developed biliary strictures, successfully managed in the follow-up. r-TPA-RP avoided retransplantation after eHAT in these cases. To our knowledge, this is the first report of the use of systemic r-TPA to treat eHAT in children. This strategy may compose an algorithm to treat eHAT that failed SR in stable patients.