Benign to Malignant Hepatic Lesion Transformation in Abernethy Malformation.

Abernethy malformation or congenital extrahepatic portosystemic shunt is an extremely rare condition whereby the portomesenteric blood drains into a systemic vein and bypasses the liver through a complete or partial shunt. Severe complications include hyperammonemia and encephalopathy, benign and malignant liver tumors, and hepatopulmonary syndrome. We describe a case where a female adult diagnosed with congenital extrahepatic portosystemic shunt subsequently developed focal nodular hyperplasia and then hepatocellular carcinoma.

Acute kidney injury in patients with cirrhosis: Acute Disease Quality Initiative (ADQI) and International Club of Ascites (ICA) joint multidisciplinary consensus meeting.

Patients with cirrhosis are prone to developing acute kidney injury (AKI), a complication associated with a markedly increased in-hospital morbidity and mortality, along with a risk of progression to chronic kidney disease. Whereas patients with cirrhosis are at increased risk of developing any phenotype of AKI, hepatorenal syndrome (HRS), a specific form of AKI (HRS-AKI) in patients with advanced cirrhosis and ascites, carries an especially high mortality risk. Early recognition of HRS-AKI is crucial since administration of splanchnic vasoconstrictors may reverse the AKI and serve as a bridge to liver transplantation, the only curative option. In 2023, a joint meeting of the International Club of Ascites (ICA) and the Acute Disease Quality Initiative (ADQI) was convened to develop new diagnostic criteria for HRS-AKI, to provide graded recommendations for the work-up, management and post-discharge follow-up of patients with cirrhosis and AKI, and to highlight priorities for further research.

Wearable bioadhesive ultrasound shear wave elastography.

Acute liver failure (ALF) is a critical medical condition defined as the rapid development of hepatic dysfunction. Conventional ultrasound elastography cannot continuously monitor liver stiffness over the course of rapidly changing diseases for early detection due to the requirement of a handheld probe. In this study, we introduce wearable bioadhesive ultrasound elastography (BAUS-E), which can generate acoustic radiation force impulse (ARFI) to induce shear waves for the continuous monitoring of modulus changes. BAUS-E contains 128 channels with a compact design with only 24 mm in the azimuth direction for comfortable wearability. We further used BAUS-E to continuously monitor the stiffness of in vivo rat livers with ALF induced by d-galactosamine over 48 hours, and the stiffness change was observed within the first 6 hours. BAUS-E holds promise for clinical applications, particularly in patients after organ transplantation or postoperative care in the intensive care unit (ICU).

Living Donor Liver Transplantation for Hepatocellular Carcinoma Within and Outside Traditional Selection Criteria: A Multicentric North American Experience.

OBJECTIVE: To evaluate long-term oncologic outcomes of patients post-living donor liver transplantation (LDLT) within and outside standard transplantation selection criteria and the added value of the incorporation of the New York-California (NYCA) score. BACKGROUND: LDLT offers an opportunity to decrease the liver transplantation waitlist, reduce waitlist mortality, and expand selection criteria for patients with hepatocellular carcinoma (HCC). METHODS: Primary adult LDLT recipients between October 1999 and August 2019 were identified from a multicenter cohort of 12 North American centers. Posttransplantation and recurrence-free survival were evaluated using the Kaplan-Meier method. RESULTS: Three hundred sixty LDLTs were identified. Patients within Milan criteria (MC) at transplantation had a 1, 5, and 10-year posttransplantation survival of 90.9%, 78.5%, and 64.1% versus outside MC 90.4%, 68.6%, and 57.7% ( P = 0.20), respectively. For patients within the University of California San Francisco (UCSF) criteria, respective posttransplantation survival was 90.6%, 77.8%, and 65.0%, versus outside UCSF 92.1%, 63.8%, and 45.8% ( P = 0.08). Fifty-three (83%) patients classified as outside MC at transplantation would have been classified as either low or acceptable risk with the NYCA score. These patients had a 5-year overall survival of 72.2%. Similarly, 28(80%) patients classified as outside UCSF at transplantation would have been classified as a low or acceptable risk with a 5-year overall survival of 65.3%. CONCLUSIONS: Long-term survival is excellent for patients with HCC undergoing LDLT within and outside selection criteria, exceeding the minimum recommended 5-year rate of 60% proposed by consensus guidelines. The NYCA categorization offers insight into identifying a substantial proportion of patients with HCC outside the MC and the UCSF criteria who still achieve similar post-LDLT outcomes as patients within the criteria.

Impact of Medicaid Expansion on Surgical Care and Outcomes for Hepatobiliary Malignancies.

BACKGROUND: As part of the Patient Protection and Affordable Care Act, some states expanded Medicaid eligibility to adults with incomes below 138% of the federal poverty line. While this resulted in an increased proportion of insured residents, its impact on the diagnosis and treatment of hepatopancreaticobiliary (HPB) cancers has not been studied. STUDY DESIGN: The National Cancer Database (NCDB) from 2010 to 2017 was used. Patients diagnosed with HPB malignancies in states which expanded in 2014 were compared to patients in non-expansion states. Subset analyses of patients who underwent surgery and those in high-risk socioeconomic groups were performed. Outcomes studied included initiation of treatment within 30 days of diagnosis, stage at diagnosis, care at high volume or academic center, perioperative outcomes, and overall survival. Adjusted difference-in-differences analysis was performed. RESULTS: A total of 345,684 patients were included, of whom 55% resided in non-expansion states and 54% were diagnosed with pancreatic cancer. Overall survival was higher in states with Medicaid expansion (HR .90, 95% CI [.88-.92], P < .01). There were also better postoperative outcomes including 30-day mortality (.67 [.57-.80], P < .01) and 30-day readmissions (.87 [.78-.97], P = .02) as well as increased likelihood of having surgery in a high-volume center (1.42 [1.32-1.53], P < .01). However, there were lower odds of initiating care within 30 days of diagnosis (.77 [.75-.80], P < .01) and higher likelihood of diagnosis with stage IV disease (1.09 [1.06-1.12], P < .01) in expansion states. CONCLUSION: While operative outcomes and overall survival from HPB cancers were better in states with Medicaid expansion, there was no improvement in timeliness of initiating care or stage at diagnosis.

A Preliminary Controlled Trial of Endoscopic Ultrasound-guided Fiducial Markers to Guide Pancreas Surgery.

OBJECTIVE: Endoscopic ultrasound (EUS) is routinely used for fiducial marker placement (FMP) to guide stereotactic radiation of pancreatic tumors, but EUS-FMP explicitly to guide surgery has not been studied in a prospective, controlled manner. Multipurpose EUS systems have been developed that facilitate simultaneous EUS-FMP at the time of biopsy. We aimed to evaluate the feasibility of EUS-FMP to guide pancreatic resection. METHODS: In this prospective trial, we enrolled patients with resectable pancreas masses undergoing tissue sampling and placed preloaded fiducials immediately after biopsy. Intraprocedure confirmation of carcinoma, neuroendocrine, and nonlymphomatous neoplasia by rapid on-site evaluation and lesion size <4 cm was required. The main outcomes were the feasibility and ease of preoperative placement and intraoperative detection of the markers using predefined Likert scales. RESULTS: In 20 patients, EUS-FMP was successful before planned surgery and placement was technically straightforward (Likert Scale: 9.1 ± 1.3; range: 1, most challenging to 10, most facile). Intraoperative detection was feasible and improved when compared with a pre-established comparator of 5 representing an equivalent lesion without a marker (Likert Scale: 7.8 ± 2.2; range: 1, most difficult to 10, most facile; P = 0.011). The mean tumor size on EUS was 1.7 ± 0.9 (range: 0.5 to 3.6) cm. CONCLUSION: EUS-FMP is feasible and safe for resectable pancreatic tumors before surgery and may assist in perioperative detection. Preloaded fiducials may be considered for placement at the time of initial referral for EUS-fine needle biopsy.

Normothermic Machine Perfusion of Donor Livers for Transplantation in the United States: A Randomized Controlled Trial.

OBJECTIVE: To compare conventional low-temperature storage of transplant donor livers [static cold storage (SCS)] with storage of the organs at physiological body temperature [normothermic machine perfusion (NMP)]. BACKGROUND: The high success rate of liver transplantation is constrained by the shortage of transplantable organs (eg, waiting list mortality >20% in many centers). NMP maintains the liver in a functioning state to improve preservation quality and enable testing of the organ before transplantation. This is of greatest potential value with organs from brain-dead donor organs (DBD) with risk factors (age and comorbidities), and those from donors declared dead by cardiovascular criteria (donation after circulatory death). METHODS: Three hundred eighty-three donor organs were randomized by 15 US liver transplant centers to undergo NMP (n = 192) or SCS (n = 191). Two hundred sixty-six donor livers proceeded to transplantation (NMP: n = 136; SCS: n = 130). The primary endpoint of the study was "early allograft dysfunction" (EAD), a marker of early posttransplant liver injury and function. RESULTS: The difference in the incidence of EAD did not achieve significance, with 20.6% (NMP) versus 23.7% (SCS). Using exploratory, "as-treated" rather than "intent-to-treat," subgroup analyses, there was a greater effect size in donation after circulatory death donor livers (22.8% NMP vs 44.6% SCS) and in organs in the highest risk quartile by donor risk (19.2% NMP vs 33.3% SCS). The incidence of acute cardiovascular decompensation at organ reperfusion, "postreperfusion syndrome," as a secondary outcome was reduced in the NMP arm (5.9% vs 14.6%). CONCLUSIONS: NMP did not lower EAD, perhaps related to the inclusion of lower-risk liver donors, as higher-risk donor livers seemed to benefit more. The technology is safe in standard organ recovery and seems to have the greatest benefit for marginal donors.

The influence of frailty on perioperative outcomes in patients undergoing surgical resection of liver metastases: a nationwide readmissions database study.

Background: Liver metastases arise frequently from primary colorectal, pancreatic, and breast cancers. Research has highlighted the patient's frailty status as an important predictor of outcomes, but the literature evaluating the role of frailty in patients with secondary metastatic disease of the liver remains limited. Using predictive analytics, we evaluated the role of frailty in patients who underwent hepatectomy for liver metastases. Methods: We used the Nationwide Readmissions Database from 2016-2017 to identify patients who underwent resection of a secondary malignant neoplasm of the liver. Patient frailty was evaluated using the Johns Hopkins Adjusted Clinical Groups (JHACG) frailty-defining diagnosis indicator. Propensity score matching was performed and Mann-Whitney U testing was used to analyze complication rates. Receiver operating characteristic (ROC) curves were created following creation of logistic regression models for predicting discharge disposition. Results: Frail patients reported significantly higher rates of nonroutine discharges, longer inpatient stays, greater costs, higher rates of acute infection, posthemorrhagic anemia, urinary tract infection (UTI), deep vein thrombosis (DVT), wound dehiscence and readmission, and greater mortality (P<0.05). Predictive models for patient discharge disposition, DVT and UTI demonstrated that the use of frailty status and age improved the area under the ROC curves significantly compared to models using age alone. Conclusions: Frailty was found to be significantly correlated with higher rates of medical complications during inpatient stay following hepatectomy in patients with liver metastasis. The inclusion of patient frailty status in predictive models improved their predictive capacity compared to those using age alone.

Living donor liver paired exchange between pediatric and adult recipients due to donor graft size mismatch.

Living donor liver transplantation is an effective means to decrease organ shortage. However, many potential living donors are currently being denied due to ABO incompatibility or inadequate donor liver volume. Liver paired exchange (LPE) provides a practical solution to overcome these obstacles, and yet the first case of LPE in the United States was only recently reported in 2020. Here, we report world's first case of LPE involving pediatric and adult recipients to avoid surgical complexity of the pediatric recipient and to increase the graft-to-recipient weight ratio of the adult recipient between 2 ABO compatible pairs. As living donor liver transplantation becomes more widely adopted, the need for pair exchange to improve surgical safety and postoperative outcomes between 2 ABO compatible pairs is likely to increase.

Transfusion-free Strategies in Liver and Pancreatic Surgery: A Predictive Model of Blood Conservation for Transfusion Avoidance in Mainstream Populations.

OBJECTIVE: The objective of this study is to (1) describe the techniques and prove the feasibility of performing complex hepatobiliary and pancreatic surgery on a Jehovah Witness (JW) population.  (2) Describe a strategy that offsets surgical blood loss by the manipulation of circulating blood volume to create reserve whole blood upon anesthesia induction. BACKGROUND: Major liver and pancreatic resections often require operative transfusions. This limits surgical options for patients who do not accept major blood component transfusions. There is also growing recognition of the negative impact of allogenic blood transfusions. METHODS: A 23-year, single-center, retrospective review of JW patients undergoing liver and pancreatic resections was performed. We describe perioperative management and patient outcomes. Acute normovolemic hemodilution (ANH) is proposed as an important strategy for offsetting blood losses and preventing the need for blood transfusion. A quantitative mathematical formula is developed to provide guidance for its use. RESULTS: One hundred one major resections were analyzed (liver n=57, pancreas n=44). ANH was utilized in 72 patients (liver n=38, pancreas n=34) with median removal of 2 units that were returned for hemorrhage as needed or at the completion of operation. There were no perioperative mortalities. Morbidity classified as Clavien grade 3 or higher occurred in 7.0% of liver resection and 15.9% of pancreatic resection patients. CONCLUSIONS: Deliberate perioperative management makes transfusion-free liver and pancreatic resections feasible. Intraoperative whole blood removal with ANH specifically preserves red cell mass, platelets, and coagulation factors for timely reinfusion. Application of the described JW transfusion-free strategy to a broader general population could lessen blood utilization costs and morbidities.

Arterial Anastomosis Using Microsurgical Techniques in Adult Live Donor Liver Transplant: A Focus on Technique and Outcomes at a Single Institution.

BACKGROUND: Microvascular hepatic artery reconstruction (MHAR) is associated with decreased rates of hepatic artery thrombosis (HAT) in living donor liver transplantation (LDLT). There is a paucity of literature describing the learning points and initiation of this technique at the institutional level. The objective of this study is to report our institutional experience using MHAR in adult LDLT with a focus on technique and outcomes. METHODS: A retrospective review of adult patients who underwent LDLT from January 2012 to December 2020 was conducted. Patients were divided into two groups, those who underwent LDLT without MHAR and with MHAR. We analyzed cases for technical data including donor and recipient artery characteristics, anastomotic techniques, intraop events, and postop complications. A Mann-Whitney test was performed to compare outcomes between non-MHAR and MHAR patients. RESULTS: Fifty non-MHAR and 50 MHAR patients met inclusion criteria. Median age at transplantation was 58 (interquartile range [IQR] 11.8) and 57.5 years (IQR 14.5), respectively. Median follow-up for MHAR patients was 12.8 months (IQR 11.6). The most common recipient arteries were the right hepatic artery (HA) (58%) and left HA (20%). Median size of recipient and donor arteries were 3.3 mm (IQR 0.7) and 3.1 mm (IQR 0.7), resulting in a median mismatch size of 0.3 mm (IQR 0.4). Median microanastomosis time was 44 minutes (IQR 0). HAT, graft failure, and mortality rates were higher in the non-MHAR cohort (6% vs. 0%, 8% vs. 0%, and 16% vs. 6%, respectively); however, these did not reach statistical significance. CONCLUSION: This study found lower rates of HAT and graft failure after implementing MHAR, though statistical significance was not achieved. Larger cohort studies are needed to further assess the potential benefit of MHAR in adult LDLT. From our experience, MHAR requires cooperation between the transplant and microsurgical teams, with technical challenges overcome with appropriate instrumentation and planning.

Long-Term Suitability of Left Gastric Artery Inflow for Arterial Perfusion of Living Donor Right Lobe Grafts.

Poorer than expected, living donor liver transplant outcomes are observed after recipient graft artery thrombosis. At grafting, the risk for later thrombosis is high if a dissected hepatic artery is used for standard reconstruction. Surgeon diagnosis of dissection requires nonstandard management with alternative technique in addition to microvascular expertise. Intimal flap repair with standard reconstruction is contingent on basis of a redo anastomosis. It is a suboptimal choice for living donor transplantation. Achieving goal graft arterial perfusion at first revascularization is crucial for superior outcomes. Managing dissection at grafting with nonstandard left gastric artery reconstruction is unreported. Our experience is limited, but this is our preferred alternative technique to standard hepatic artery reconstruction complicated by dissection. Here, we describe our two-case experience with left gastric arterialized grafts for management of dissection. Our living donor graft recipients with alternatively arterialized grafts are now 6- and 2-years posttransplant.

Living Liver Donation Does not Significantly Affect Long-Term Life, Disability, or Medical Insurability.

INTRODUCTION: The growing practice of living liver donation requires comprehensive understanding of the financial implications for living liver donors. While obtaining and maintaining insurance is important to financial health, little is known about the impact of liver donation on future insurability. RESEARCH QUESTIONS: The purpose of this study was to evaluate the donors' experiences with insurance following donation and identify the insurance provider-driven factors that contribute to donor insurability. DESIGN: A two center cohort of living donors with donation between January 2000 and December 2018 (N = 442) were surveyed about postdonation insurance experiences. To understand insurance provider practices towards liver donors, life (n = 11) and disability (n = 4) insurance underwriters were asked to provide policy quotes for a standardized living liver donor profile. RESULTS: Responses (N = 101) were received by August 2020 (response rate = 22.9%). Living liver donors reported owning life (58%), disability (35%), and medical (87%) insurance at rates comparable to the general population with low proportions reporting difficulty obtaining these insurance types (9%, 9%, 4%, respectively). Post-donation life insurance ownership was associated with post-donation employment (P = 0.01). Underwriter responses indicate life and disability insurability were adversely affected up to 12 months following donation. CONCLUSIONS: Living liver donors did not have difficulty maintaining insurance in the long-term but should be counseled to purchase insurance prior to surgery as short-term insurability may be affected. Perception of difficulty obtaining insurance following donation remains of significant concern among living donors. Further collaboration between the transplant community and insurance companies is warranted.

Adaptation of Imaging Mass Cytometry to Explore the Single Cell Alloimmune Landscape of Liver Transplant Rejection.

Rejection continues to be an important cause of graft loss in solid organ transplantation, but deep exploration of intragraft alloimmunity has been limited by the scarcity of clinical biopsy specimens. Emerging single cell immunoprofiling technologies have shown promise in discerning mechanisms of autoimmunity and cancer immunobiology. Within these applications, Imaging Mass Cytometry (IMC) has been shown to enable highly multiplexed, single cell analysis of immune phenotypes within fixed tissue specimens. In this study, an IMC panel of 10 validated markers was developed to explore the feasibility of IMC in characterizing the immune landscape of chronic rejection (CR) in clinical tissue samples obtained from liver transplant recipients. IMC staining was highly specific and comparable to traditional immunohistochemistry. A single cell segmentation analysis pipeline was developed that enabled detailed visualization and quantification of 109,245 discrete cells, including 30,646 immune cells. Dimensionality reduction identified 11 unique immune subpopulations in CR specimens. Most immune subpopulations were increased and spatially related in CR, including two populations of CD45+/CD3+/CD8+ cytotoxic T-cells and a discrete CD68+ macrophage population, which were not observed in liver with no rejection (NR). Modeling via principal component analysis and logistic regression revealed that single cell data can be utilized to construct statistical models with high consistency (Wilcoxon Rank Sum test, p=0.000036). This study highlights the power of IMC to investigate the alloimmune microenvironment at a single cell resolution during clinical rejection episodes. Further validation of IMC has the potential to detect new biomarkers, identify therapeutic targets, and generate patient-specific predictive models of clinical outcomes in solid organ transplantation.

The role of graft to recipient weight ratio on enhanced recovery of the recipient after living donor liver transplantation - A systematic review of the literature and expert panel recommendations.

BACKGROUND: There continues to be debate about the lower limit of graft-to-recipient weight ratio (GRWR) for living donor liver transplant (LDLT). OBJECTIVES: To identify the lower limit of GRWR compatible with enhanced recovery after living donor liver transplant and to provide international expert panel recommendations. DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. Studies assessing how GRWR affects recipient outcomes such as small for size syndrome, other complications, patient and graft survival, and length of stay were included. PROTOCOL REGISTRATION: CRD42021260794. RESULTS: Twenty articles were included in the qualitative synthesis, and all were retrospective observational studies. There was heterogeneity in the definition of study cohorts and key outcome measures such as small-for-size syndrome. Most studies lacked risk adjustment given limited single-center sample size. GRWR of ≥ .8% is associated with enhanced recovery. Recipients of grafts with GRWR < .8%, however, were found to have similar outcomes as those with ≥ .8% when appropriate consideration is made for portal flow modulation and recipient illness severity. CONCLUSIONS: GRWR ≥ .8% is often compatible with enhanced recovery, but grafts < .8% can be used in selected LDLT recipients with optimal donor-recipient selection, surgical technique, and perioperative management (Quality of Evidence; Low | Grade of Recommendation; Strong).

Independent Assessment of the Children's Hepatic Tumors International Collaboration Risk Stratification for Hepatoblastoma and the Association of Tumor Histological Characteristics With Prognosis.

Importance: Hepatoblastoma is the most common pediatric liver malignant neoplasm, and accurate risk stratification is essential for guiding treatment. Objective: To validate the Children's Hepatic Tumors International Collaboration-Hepatoblastoma Stratification (CHIC-HS) in an independent cohort of patients with hepatoblastoma and evaluate the association of pretreatment hepatoblastoma histological subtype with prognosis. Design, Setting, and Participants: This is a single-institution retrospective cohort study of 96 pediatric patients with hepatoblastoma diagnosed and treated between June 1, 2000, and December 31, 2016, with recent therapy and independent of the CHIC-HS discovery cohort. Each patient was assigned a risk group according to CHIC-HS. The histological characteristics of each tumor were assessed based on the International Pediatric Liver Tumor Consensus Classification. Data were analyzed from May 2018 to May 2019. Main Outcomes And Measures: The main outcomes were event-free survival (EFS) and overall survival (OS). Cox regression analysis was used to examine the associations of patient characteristics and tumor histological characteristics with survival. Results: A total of 96 patients (median [range] age, 1.9 [0.4-18] years; 36 [38%] girls and 60 [63%] boys) were assessed, including 15 with very low risk, 28 with low risk, 23 with intermediate risk, and 30 with high risk, according to CHIC-HS criteria. There were a total of 13 cancer-related deaths; median (range) follow-up was 3.5 (0.1-17.8) years for those alive at the last follow-up. The estimated 5-year OS rates were 100% in the very low-risk group, 94.7% (95% CI, 68.1%-99.2%) in the low-risk group, 89.2% (95% CI, 63.1%-97.2%) in the intermediate-risk group, and 57.9% (95% CI, 34.6%-75.5%) in the high-risk group. In a multivariable analysis, we confirmed that CHIC-HS significantly estimated EFS (high-risk group vs very low- and low-risk groups: hazard ratio [HR], 45.59; 95% CI, 9.39-209.5; P < .001) and OS (high-risk group vs very low- and low-risk groups: HR, 21.95; 95% CI, 2.76-174.29; P < .001). In the subcohort of 84 patients for whom pretreatment tumor histological data were available, tumor epithelial histological subtypes were found to be significantly associated with both EFS and OS. Patients in the CHIC-HS high-risk group and with embryonal-only histological subtype had the highest risk of relapse or disease progression (high-risk: HR, 42.62; 95% CI, 9.91-203.9; embryonal: HR, 3.28; 95% CI, 1.21-8.9) and death (high-risk: HR, 18.78; 95% CI, 2.31-152.84; embryonal: HR, 7.12; 95% CI, 1.51-33.52). Conclusions and Relevance: This cohort study found that CHIC-HS performed as expected in an independent cohort that was more recently treated. Incorporation of pretreatment tumor histological data into CHIC-HS may provide additional prognostic value.

Microscope-Assisted Arterial Anastomosis in Adult Living Donor Liver Transplantation: A Systematic Review and Meta-analysis of Outcomes.

BACKGROUND: Living donor liver transplantation (LDLT) has expanded the availability of liver transplant but has been associated with early technical complications including the devastating complication of hepatic artery thrombosis (HAT), which has been reported to occur in 14% to 25% of LDLT using standard anastomotic techniques. Microvascular hepatic artery reconstruction (MHAR) has been implemented in an attempt to decrease rates of HAT. The purpose of this study was to review the available literature in LDLT, specifically related to MHAR to determine its impact on rates of posttransplant complications including HAT. METHODS: A systematic review was conducted using PubMed/Medline and Web of Science. Case series and reviews describing reports of microscope-assisted hepatic artery anastomosis in adult patients were considered for meta-analysis of factors contributing to HAT. RESULTS: In all, 462 abstracts were screened, resulting in 20 studies that were included in the meta-analysis. This analysis included 2,457 patients from eight countries. The pooled rate of HAT was 2.20% with an overall effect size of 0.00906. CONCLUSION: Systematic literature review suggests that MHAR during LDLT reduces vascular complications and improves outcomes posttransplant. Microvascular surgeons and transplant surgeons should collaborate when technical challenges such as small vessel size, short donor pedicle, or dissection of the recipient vessel wall are present.