Mortality and morbidity after combined heart and liver transplantation in the failing Fontan: An updated dual center retrospective study.

INTRODUCTION: As the adult Fontan population with Fontan associated liver disease continues to increase, more patients are being referred for transplantation, including combined heart and liver transplantation. METHODS: We report updated mortality and morbidity outcomes after combined heart and liver transplant in a retrospective cohort series of 40 patients (age 14 to 49 years) with Fontan circulation across two centers from 2006-2022. RESULTS: The 30-day, 1-year, 5-year and 10-year survival rate was 90%, 80%, 73% and 73% respectively. Sixty percent of patients met a composite comorbidity of needing either post-transplant mechanical circulatory support, renal replacement therapy or tracheostomy. Cardiopulmonary bypass time > 283 min (4.7 h) and meeting the composite comorbidity were associated with mortality by Kaplan Meier analysis. CONCLUSION: Further study to mitigate early mortality and the above comorbidities as well as the high risk of bleeding and vasoplegia in this patient population is warranted.

US Liver Transplant Outcomes After Normothermic Regional Perfusion vs Standard Super Rapid Recovery.

Importance: Normothermic regional perfusion (NRP) is an emerging recovery modality for transplantable allografts from controlled donation after circulatory death (cDCD) donors. In the US, only 11.4% of liver recipients who are transplanted from a deceased donor receive a cDCD liver. NRP has the potential to safely expand the US donor pool with improved transplant outcomes as compared with standard super rapid recovery (SRR). Objective: To assess outcomes of US liver transplants using controlled donation after circulatory death livers recovered with normothermic regional perfusion vs standard super rapid recovery. Design, Setting, and Participants: This was a retrospective, observational cohort study comparing liver transplant outcomes from cDCD donors recovered by NRP vs SRR. Outcomes of cDCD liver transplant from January 2017 to May 2023 were collated from 17 US transplant centers and included livers recovered by SRR and NRP (thoracoabdominal NRP [TA-NRP] and abdominal NRP [A-NRP]). Seven transplant centers used NRP, allowing for liver allografts to be transplanted at 17 centers; 10 centers imported livers recovered via NRP from other centers. Exposures: cDCD livers were recovered by either NRP or SRR. Main Outcomes and Measures: The primary outcome was ischemic cholangiopathy (IC). Secondary end points included primary nonfunction (PNF), early allograft dysfunction (EAD), biliary anastomotic strictures, posttransplant length of stay (LOS), and patient and graft survival. Results: A total of 242 cDCD livers were included in this study: 136 recovered by SRR and 106 recovered by NRP (TA-NRP, 79 and A-NRP, 27). Median (IQR) NRP and SRR donor age was 30.5 (22-44) years and 36 (27-49) years, respectively. Median (IQR) posttransplant LOS was significantly shorter in the NRP cohort (7 [5-11] days vs 10 [7-16] days; P < .001). PNF occurred only in the SRR allografts group (n = 2). EAD was more common in the SRR cohort (123 of 136 [56.1%] vs 77 of 106 [36.4%]; P = .007). Biliary anastomotic strictures were increased 2.8-fold in SRR recipients (7 of 105 [6.7%] vs 30 of 134 [22.4%]; P = .001). Only SRR recipients had IC (0 vs 12 of 133 [9.0%]; P = .002); IC-free survival by Kaplan-Meier was significantly improved in NRP recipients. Patient and graft survival were comparable between cohorts. Conclusion and Relevance: There was comparable patient and graft survival in liver transplant recipients of cDCD donors recovered by NRP vs SRR, with reduced rates of IC, biliary complications, and EAD in NRP recipients. The feasibility of A-NRP and TA-NRP implementation across multiple US transplant centers supports increasing adoption of NRP to improve organ use, access to transplant, and risk of wait-list mortality.

Characterizing proximity and transfers of deceased organ donors to donor care units in the United States.

Some United States organ procurement organizations transfer deceased organ donors to donor care units (DCUs) for recovery procedures. We used Organ Procurement and Transplantation Network data, from April 2017 to June 2021, to describe the proximity of adult deceased donors after brain death to DCUs and understand the impact of donor service area (DSA) boundaries on transfer efficiency. Among 19 109 donors (56.1% of the cohort) in 25 DSAs with DCUs, a majority (14 593 [76.4%]) were in hospitals within a 2-hour drive. In areas with DCUs detectable in the study data set, a minority of donors (3582 of 11 532 [31.1%]) were transferred to a DCU; transfer rates varied between DSAs (median, 27.7%, range, 4.0%-96.5%). Median hospital-to-DCU driving times were not meaningfully shorter among transferred donors (50 vs 51 minutes for not transferred, P < .001). When DSA boundaries were ignored, 3241 cohort donors (9.5%) without current DCU access were managed in hospitals within 2 hours of a DCU and thus potentially eligible for transfer. In summary, approximately half of United States deceased donors after brain death are managed in hospitals in DSAs with a DCU. Transfer of donors between DSAs may increase DCU utilization and improve system efficiency.

Living Donor Liver Transplantation for Adults With High Model for End-stage Liver Disease Score: The US Experience.

BACKGROUND: Outcomes after living-donor liver transplantation (LDLT) at high Model for End-stage Liver Disease (MELD) scores are not well characterized in the United States. METHODS: This was a retrospective cohort study using Organ Procurement and Transplantation Network data in adults listed for their first liver transplant alone between 2002 and 2021. Cox proportional hazards models evaluated the association of MELD score (<20, 20-24, 25-29, and ≥30) and patient/graft survival after LDLT and the association of donor type (living versus deceased) on outcomes stratified by MELD. RESULTS: There were 4495 LDLTs included with 5.9% at MELD 25-29 and 1.9% at MELD ≥30. LDLTs at MELD 25-29 and ≥30 LDLT have substantially increased since 2010 and 2015, respectively. Patient survival at MELD ≥30 was not different versus MELD <20: adjusted hazard ratio 1.67 (95% confidence interval, 0.96-2.88). However, graft survival was worse: adjusted hazard ratio (aHR) 1.69 (95% confidence interval, 1.07-2.68). Compared with deceased-donor liver transplant, LDLT led to superior patient survival at MELD <20 (aHR 0.92; P = 0.024) and 20-24 (aHR 0.70; P < 0.001), equivalent patient survival at MELD 25-29 (aHR 0.97; P = 0.843), but worse graft survival at MELD ≥30 (aHR 1.68, P = 0.009). CONCLUSIONS: Although patient survival remains acceptable, the benefits of LDLT may be lost at MELD ≥30.

Deceased Organ Donor Management and Organ Distribution From Organ Procurement Organization-Based Recovery Facilities Versus Acute-Care Hospitals.

Introduction: Organ recovery facilities address the logistical challenges of hospital-based deceased organ donor management. While more organs are transplanted from donors in facilities, differences in donor management and donation processes are not fully characterized. Research Question: Does deceased donor management and organ transport distance differ between organ procurement organization (OPO)-based recovery facilities versus hospitals? Design: Retrospective analysis of Organ Procurement and Transplant Network data, including adults after brain death in 10 procurement regions (April 2017-June 2021). The primary outcomes were ischemic times of transplanted hearts, kidneys, livers, and lungs. Secondary outcomes included transport distances (between the facility or hospital and the transplant program) for each transplanted organ. Results: Among 5010 deceased donors, 51.7% underwent recovery in an OPO-based recovery facility. After adjustment for recipient and system factors, mean differences in ischemic times of any transplanted organ were not significantly different between donors in facilities and hospitals. Transplanted hearts recovered from donors in facilities were transported further than hearts from hospital donors (median 255 mi [IQR 27, 475] versus 174 [IQR 42, 365], P = .002); transport distances for livers and kidneys were significantly shorter (P < .001 for both). Conclusion: Organ recovery procedures performed in OPO-based recovery facilities were not associated with differences in ischemic times in transplanted organs from organs recovered in hospitals, but differences in organ transport distances exist. Further work is needed to determine whether other observed differences in donor management and organ distribution meaningfully impact donation and transplantation outcomes.

Significant Reduction in Posttransplant Hepatocellular Carcinoma Recurrence in the Post 6-Mo Waiting Policy Era.

BACKGROUND: In 2015, the United Network for Organ Sharing implemented a policy introducing a 6-mo waiting period before granting model for end-stage liver disease exception points to liver transplant (LT) candidates with hepatocellular carcinoma (HCC). This study analyzes the policy impact on post-LT HCC recurrence. METHODS: This was a United Network for Organ Sharing retrospective cohort study of patients with HCC who underwent LT from January 1, 2010, to May 31, 2019. HCC-specific data included alpha-fetoprotein, tumor characteristics, locoregional therapy (LRT), and explant data used to calculate the Risk Estimation of Tumor Recurrence After Transplant score. The primary exposure was pre-/post-policy era, divided on October 8, 2015. Survival analysis techniques were used to evaluate the unadjusted and sequentially adjusted association between policy era and HCC recurrence, accounting for competing risks. RESULTS: A total of 7940 patients were included, 5879 (74.0%) pre-policy era and 2061 (26.0%) post-policy era. Post-policy patients were older, received more LRT, and had lower alpha-fetoprotein levels and smaller tumor sizes at transplant. Incidence rates of HCC recurrence were 19.8 and 13.7 events per 1000 person-years for pre- and post-policy eras, respectively. Post-policy era was associated with an unadjusted 35% reduction in the risk of HCC recurrence (P < 0.001). After adjusting for recipient, donor, and tumor characteristics at listing this association remained (subhazard ratio 0.69; 95% confidence interval, 0.55-0.86; P = 0.001); however, after additionally adjusting for LRT episodes and Risk Estimation of Tumor Recurrence After Transplant score, there was no longer a statistically significant association (subhazard ratio 0.77; 95% confidence interval, 0.59-1.00; P = 0.054). CONCLUSIONS: We observed a significant reduction in post-LT HCC recurrence after policy implementation. This may be due to waitlist selection of healthier patients, increased LRT utilization, and potential selection of favorable tumor biology.

Can ex-situ normothermic perfusion improve graft survival compared to static cold storage among donation after circulatory death liver allografts?

Limited data suggest that ex-situ normothermic liver perfusion (ENLP) may improve the outcomes of donation after circulatory death (DCD) liver transplants compared to static cold storage (SCS). All adult DCD liver transplants performed between 2016 and 2021 were identified in the United Network of Organ Sharing database. ENLP liver transplants were compared to SCS using inverse probability of treatment weighting to balance clinical and demographic confounders. The primary analysis simulated intention-to-treat with inverse probability of treatment weighting-adjusted Cox models. Compared to SCS DCDs (N = 3,079), recipients of ENLP DCDs (N = 65) had lower Model of End Stage Liver Disease scores at transplant (16.5 v. 18.8, p = 0.033), longer wait times (468 ± 720 vs. 246 ± 467 d; p < 0.001), and received livers from donors with a greater BMI (29.2 vs. 27.5; p = 0.008). ENLP preservation was associated with a lower risk of graft failure (HR 0.31 vs. SCS, 95% CI:0.12-0.86, p = 0.023) and a lower incidence of retransplantation. A sub-analysis restricted to the 20 centers performing ENLP, encompassing 946 SCS DCDs, demonstrated similar results: (HR 0.33 vs. SCS, 95% CI: 0.13-0.94, p = 0.021). Among 111 patients who required retransplantation and where the etiology of graft failure was identified, graft failure due to ischemic cholangiopathy was noted in 1 ENLP and 46 SCS. In this retrospective analysis of the early US DCD ENLP experience, there may exist a graft survival benefit to transplants performed with ENLP compared to SCS.

Organ Transplantation Outcomes of Deceased Organ Donors in Organ Procurement Organization-Based Recovery Facilities Versus Acute-Care Hospitals.

INTRODUCTION: Recovery of donated organs at organ procurement organization (OPO)-based recovery facilities has been proposed to improve organ donation outcomes, but few data exist to characterize differences between facilities and acute-care hospitals. RESEARCH QUESTION: To compare donation outcomes between organ donors that underwent recovery procedures in OPO-based recovery facilities and hospitals. DESIGN: Retrospective study of Organ Procurement and Transplantation Network data. From a population-based sample of deceased donors after brain death April 2017 to June 2021, donation outcomes were examined in 10 OPO regions with organ recovery facilities. Primary exposure was organ recovery procedure in an OPO-based organ recovery. Primary outcome was the number of organs transplanted per donor. Multivariable regression models were used to adjust for donor characteristics and managing OPO. RESULTS: Among 5010 cohort donors, 2590 (51.7%) underwent recovery procedures in an OPO-based facility. Donors in facilities differed from those in hospitals, including recovery year, mechanisms of death, and some comorbid diseases. Donors in OPO-based facilities had higher total numbers of organs transplanted per donor (mean 3.5 [SD1.8] vs 3.3 [SD1.8]; adjusted mean difference 0.27, 95% confidence interval 0.18-0.36). Organ recovery at an OPO-based facility was also associated with more lungs, livers, and pancreases transplanted. CONCLUSION: Organ recovery procedures at OPO-based facilities were associated with more organs transplanted per donor than in hospitals. Increasing access to OPO-based organ recovery facilities may improve rates of organ transplantation from deceased organ donors, although further data are needed on other important donor management quality metrics.

The effectiveness and safety of antibody induction immunosuppression in a large cohort of United States pediatric liver transplant recipients.

Data on the potential benefits and risks of induction therapy in pediatric liver transplantation (LT) are limited. This was a retrospective cohort study of 2748 pediatric LT recipients at 26 children's hospitals between January 1, 2006 to May 31, 2017 using data from the pediatric health information system linked to the United Network for Organ Sharing database. The induction regimen was obtained from the pediatric health information system day-by-day pharmacy resource utilization. Cox proportional hazards evaluated the association of induction regimen (none/corticosteroid-only, nondepleting, and depleting) on patient and graft survival. Additional outcomes, including opportunistic infections and posttransplant lymphoproliferative disorder, were studied using multivariable logistic regression. Overall, 64.9% received none/corticosteroid-only induction, whereas 28.1% received nondepleting, 8.3% received depleting, and 2.5% other antibody regimens. Differences in patient characteristics were small, but center practices were heterogeneous. Compared with none/corticosteroid-only induction, nondepleting induction was associated with reduced acute rejection (odd ratio [OR], 0.53; P <.001) but with the increased posttransplant lymphoproliferative disorder (OR, 1.75; P =.021). Depleting induction was associated with improved graft survival (hazard ratio [HR], 0.64; P =.028) but with increased noncytomegalovirus opportunistic infections (OR, 1.46; P =.046). Depleting induction is underused yet may offer long-term benefits in this large multicenter cohort. Greater consensus guidance in this aspect of pediatric LT care is warranted.

Center expansion of liver transplants using donation after circulatory death organs is associated with reduced overall waitlist mortality.

INTRODUCTION: Waitlist outcomes in liver transplantation (LT) for individual recipients are improved by use of allografts procured through donation after circulatory death (DCD). However, the impact of increased DCD acceptance on overall center outcomes is unknown. METHODS: Using the United Network for Organ Sharing database, 88 centers performing an average of ≥10 LTs/year between 1/2004 and 12/2019 were compared by percent DCD use quartile and categorized into four phenotypes according to temporal usage trends. Overall center median Model for End-stage Liver Disease at LT (MMaT), waitlist mortality, and waiting time were evaluated. RESULTS: The overall DCD rate was 6.1% (N = 4906/80,709), ranging from 0% to 25.5%. Centers in the top DCD use quartile had lower MMaT (24 vs. 26; p < .001) and shorter overall waiting times (median 66 days vs. 90 days; p < .001) compared to bottom quartile centers. MMaT increased less over time at centers with increasing DCD use and was lower than at centers with declining DCD use (27 vs. 32; p = .017). Overall waitlist mortality between 2016 and 2019 was lower at increasing DCD use centers (17.8% vs. 22.5%, p = .034), yet did not affect 1-year mortality (p = .747). CONCLUSIONS: The improved waitlist outcomes at centers with expanded DCD use extend beyond DCD recipients alone without negative consequences to overall post-LT center metrics.

Induction Immunosuppression Does Not Worsen Tumor Recurrence After Liver Transplantation for Hepatocellular Carcinoma.

BACKGROUND: Prior studies are inconsistent regarding the impact of antibody induction therapy on outcomes after liver transplantation (LT) for hepatocellular carcinoma (HCC). METHODS: Adults transplanted with HCC exception priority were identified from February 27, 2002, to March 31, 2019, using the United Network for Organ Sharing database. Time-to-event analyses evaluated the association of antibody induction therapy (none, nondepleting induction [NDI], depleting induction [DI]) with overall post-LT patient survival and HCC recurrence. Separate multivariable models adjusted for tumor characteristics on either last exception or on explant. The interaction of induction and maintenance regimen at LT discharge was investigated. RESULTS: Among 22 535 LTs for HCC, 17 688 (78.48%) received no antibody induction, 2984 (13.24%) NDI, and 1863 (8.27%) DI. Minimal differences in patient and tumor characteristics were noted between induction groups, and there was significant center variability in practices. NDI was associated with improved survival, particularly when combined with a calcineurin inhibitor (CNI) and antimetabolite (hazard ratio [HR] 0.73 versus no induction plus 3-drug therapy in the last exception model [ P < 0.001]; HR 0.64 in the explant model [ P = 0.011]). The combination of DI with CNI alone was also protective (HR 0.43; P = 0.003). Neither NDI nor DI was associated with tumor recurrence (all P > 0.1). However, increased HCC recurrence was observed with no induction plus CNI monotherapy (HR 1.47, P = 0.019; versus no induction plus 3-drug therapy). CONCLUSIONS: In conclusion, induction immunosuppression was not associated with worse post-LT outcomes in patients transplanted with HCC exception priority. An improvement in survival was possibly observed with NDI.

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.

Trends and Outcomes of Hypothermic Machine Perfusion Preservation of Kidney Allografts in Simultaneous Liver and Kidney Transplantation in the United States.

Optimal kidney graft outcomes after simultaneous liver-kidney (SLK) transplant may be threatened by the increased cold ischemia time and hemodynamic perturbations of dual organ transplantation. Hypothermic machine perfusion (MP) of kidney allografts may mitigate these effects. We analyzed U.S. trends and renal outcomes of hypothermic non-oxygenated MP vs. static cold storage (CS) of kidney grafts from 6,689 SLK transplants performed between 2005 and 2020 using the United Network for Organ Sharing database. Outcomes included delayed graft function (DGF), primary non-function (PNF), and kidney graft survival (GS). Overall, 17.2% of kidney allografts were placed on MP. Kidney cold ischemia time was longer in the MP group (median 12.8 vs. 10.0 h; p < 0.001). Nationally, MP utilization in SLK increased from <3% in 2005 to >25% by 2019. Center preference was the primary determinant of whether a graft underwent MP vs. CS (intraclass correlation coefficient 65.0%). MP reduced DGF (adjusted OR 0.74; p = 0.008), but not PNF (p = 0.637). Improved GS with MP was only observed with Kidney Donor Profile Index <20% (HR 0.71; p = 0.030). Kidney MP has increased significantly in SLK in the U.S. in a heterogeneous manner and with variable short-term benefits. Additional studies are needed to determine the ideal utilization for MP in SLK.

Incidence of acute rejection and patient survival in combined heart-liver transplantation.

Combined heart-liver transplantation (CHLT) is indicated for patients with concomitant end-stage heart and liver disease or patients with amyloid heart disease where liver transplantation mitigates progression. Limited data suggest that the liver allograft provides immunoprotection for heart and kidney allografts in combined transplantation from the same donor. We hypothesized that CHLT reduces the incidence of acute cellular rejection (ACR) and the development of de novo donor-specific antibodies (DSAs) compared with heart-alone transplantation (HA). We conducted a retrospective analysis of 32 CHLT and 280 HA recipients in a single-center experience. The primary outcome was incidence of ACR based on protocol and for-cause myocardial biopsy. Rejection was graded by the International Society of Heart and Lung Transplantation guidelines with Grade 2R and higher considered significant. Secondary outcomes included the development of new DSAs, cardiac function, and patient and cardiac graft survival rates. Of CHLT patients, 9.7% had ACR compared with 45.3% of HA patients (p < 0.01). Mean pretransplant calculated panel reactive antibody (cPRA) levels were similar between groups (CHLT 9.4% vs. HA 9.5%; p = 0.97). Among patients who underwent testing, 26.9% of the CHLT and 16.7% of HA developed DSA (p = 0.19). Despite the difference in ACR, patient and cardiac graft survival rates were similar at 5 years (CHLT 82.1% vs. HA 80.9% [p = 0.73]; CHLT 82.1% vs. HA 80.9% [p = 0.73]). CHLT reduced the incidence of ACR in the cardiac allograft, suggesting that the liver offers immunoprotection against cellular mechanisms of rejection without significant impacts on patient and cardiac graft survival rates. CHLT did not reduce the incidence of de novo DSA, possibly portending similar long-term survival among cardiac allografts in CHLT and HA.

Acute Kidney Injury in Deceased Organ Donors and Kidney Transplant Outcomes: A National Cohort Study Using a Novel Data Source.

OBJECTIVE: The aim of this study was to determine graft function and survival for kidney transplants from deceased donors with acute kidney injury (AKI) that persists at the time of organ procurement. BACKGROUND: Kidneys from donors with AKI are often discarded and may provide an opportunity to selectively expand the donor pool. METHODS: Using Organ Procurement and Transplantation Network and DonorNet data, we studied adult kidney-only recipients between May 1, 2007 and December 31, 2016. DonorNet was used to characterize longitudinal creatinine trends and urine output. Donor AKI was defined using KDIGO guidelines and terminal creatinine ≥1.5 mg/dL. We compared outcomes between AKI kidneys versus "ideal comparator" kidneys from donors with no or resolved AKI stage 1 plus terminal creatinine <1.5mg/dL. We fit proportional hazards models and hierarchical linear regression models for the primary outcomes of all-cause graft failure (ACGF) and 12-month estimated glomerular filtration rate (eGFR), respectively. RESULTS: We identified 7660 donors with persistent AKI (33.2% with AKI stage 3) from whom ≥1 kidney was transplanted. Observed rates of ACGF within 3 years were similar between recipient groups (15.5% in AKI vs 15.1% ideal comparator allografts, P = 0.2). After risk adjustment, ACGF was slightly higher among recipients of AKI kidneys (adjusted hazard ratio 1.05, 95% confidence interval: 1.01-1.09). The mean 12-month eGFR for AKI kidney recipients was lower, but differences were not clinically important (56.6 vs 57.5 mL/min/1.73m 2 for ideal comparator kidneys; P < 0.001). There were 2888 kidneys discarded from donors with AKI, age ≤65 years, without hypertension or diabetes, and terminal creatinine ≤4 mg/dL. CONCLUSION: Kidney allografts from donors with persistent AKI are often discarded, yet those that were transplanted did not have clinically meaningful differences in graft survival and function.