Antony Moheb Attia

All Publications

• In policy and in practice: expedited placement and allocation out of sequence in liver transplantation. American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons Attia, A., Nakayama, T., Ahn, D. J., York, T., Wehrle, C. J., Cheng, X. S., Charu, V., Kwong, A. J., Stutchfield, B. M., Segev, D., Gentry, S., Melcher, M., Sasaki, K. 2026

  Abstract

  United States liver transplant policy debate has conflated two distinct mechanisms: Expedited Placement (OPTN Policy 9.10), a formal route for late turndowns when in-sequence offering risks non-utilization, and allocation out-of-sequence (AOOS), informal organ procurement organization (OPO) outreach beyond the match-run. Linking Standard Transplant Analysis and Research files to the Potential Transplant Recipient database (March 2021-December 2025), we classified 61,626 match-runs (41,638 transplanted) by pathway: in-sequence <50 offers (n=32,165), in-sequence ≥50 (n=3,450), AOOS (n=5,486), and Expedited Placement (n=537). AOOS rose 132% while Expedited Placement grew 6% and was absent in 12 of 55 OPOs. Before acceptance, a median 10 centers were contacted per AOOS graft versus 6 in-sequence, and AOOS refusals far more often covered entire waitlists (median 28 patients declined per donor versus 2). Most in-sequence acceptances occurred before donor cross-clamp (median 17.0 hours prior), whereas AOOS and Expedited Placement acceptances occurred after (0.15 and 2.42 hours). AOOS transplants occurred more frequently at centers with higher in-sequence acceptance of hard-to-place organs (Spearman 0.866), with comparable survival. These patterns are consistent with AOOS occurring after in-sequence placement has stalled, rather than as early bypass of in-sequence candidates; the circumstance Expedited Placement was designed for.

  View details for DOI 10.1016/j.ajt.2026.09.022

  View details for PubMedID 42763043

• Effect of recipient age on prioritisation for liver transplantation in the UK: a population-based modelling study. The lancet. Healthy longevity Attia, A., Webb, J., Connor, K., Johnston, C. J., Williams, M., Gordon-Walker, T., Rowe, I. A., Harrison, E. M., Stutchfield, B. M. 2024; 5 (5): e346-e355

  Abstract

  Following the introduction of an algorithm aiming to maximise life-years gained from liver transplantation in the UK (the transplant benefit score [TBS]), donor livers were redirected from younger to older patients, mortality rate equalised across the age range and short-term waiting list mortality reduced. Understanding age-related prioritisation has been challenging, especially for younger patients and clinicians allocating non-TBS-directed livers. We aimed to assess age-related prioritisation within the TBS algorithm by modelling liver transplantation prioritisation based on data from a UK transplant unit and comparing these data with other regions.In this population-based modelling study, serum parameters and age at liver transplantation assessment of patients attending the Scottish Liver Transplant Unit, Edinburgh, UK, between December, 2002, and November, 2023, were combined with representative synthetic data to model TBS survival predictions, which were compared according to age group (25-49 years vs ≥60 years), chronic liver disease severity, and disease cause. Models for end-stage liver disease (UKELD [UK], MELD [Eurotransplant region], and MELD 3.0 [USA]) were used as validated comparators of liver disease severity.Of 2093 patients with chronic liver disease, 1808 (86%) had complete datasets and liver disease parameters consistent with eligibility for the liver transplant waiting list in the UK (UKELD ≥49). Disease severity as assessed by UKELD, MELD, and MELD 3.0 did not differ by age (median UKELD scores of 56 for patients aged ≥60 years vs 56 for patients aged 25-49 years; MELD scores of 16 vs 16; and MELD 3.0 scores of 18 vs 18). TBS increased with advancing age (R=0·45, p<0·0001). TBS predicted that transplantation in patients aged 60 years or older would provide a two-fold greater net benefit at 5 years than in patients aged 25-49 years (median TBS 1317 [IQR 1116-1436] in older patients vs 706 [411-1095] in younger patients; p<0·0001). Older patients were predicted to have shorter survival without transplantation than younger patients (263 days [IQR 144-473] in older patients vs 861 days [448-1164] in younger patients; p<0·0001) but similar survival after transplantation (1599 days [1563-1628] vs 1573 days [1525-1614]; p<0·0001). Older patients could reach a TBS for which a liver offer was likely below minimum criteria for transplantation (UKELD <49), whereas many younger patients were required to have high-urgent disease (UKELD >60). US and Eurotransplant programmes did not prioritise according to age.The UK liver allocation algorithm prioritises older patients for transplantation by predicting that advancing age increases the benefit from liver transplantation. Restricted follow-up and biases in waiting list data might limit the accuracy of these benefit predictions. Measures beyond overall waiting list mortality are required to fully capture the benefits of liver transplantation.None.

  View details for DOI 10.1016/S2666-7568(24)00044-8

  View details for PubMedID 38705152

• Implausible algorithm output in UK liver transplantation allocation scheme: importance of transparency. Lancet (London, England) Attia, A., Rowe, I. A., Harrison, E. M., Gordon-Walker, T., Stutchfield, B. M. 2023; 401 (10380): 911-912

  View details for DOI 10.1016/S0140-6736(23)00114-9

  View details for PubMedID 36870362

• Under-Capture of Candidates Supported by Temporary Mechanical Circulatory Support in the OPTN STAR Registry. JACC. Advances Ahn, D. J., Attia, A., Nakayama, T., Parker, W. F., Khush, K. K. 2026; 5 (10 Pt 2): 103213

  View details for DOI 10.1016/j.jacadv.2026.103213

  View details for PubMedID 42721605

• Does reperfusion time affect chances of HCC recurrence after liver transplantation? HPB : the official journal of the International Hepato Pancreato Biliary Association Gangaram, P., Attia, A. M., Ahn, D., Nakayama, T., Sasaki, K. 2026

  View details for DOI 10.1016/j.hpb.2026.08.2004

  View details for PubMedID 42767850

• The Benefit of Sequential Normothermic Regional Perfusion and Hypothermic Machine Perfusion in Kidney Transplantation From Donation After Circulatory Death Donors. Clinical transplantation Nakayama, T., Fu, S. J., Attia, A. M., Ahn, D. J., Pham, T. A., Melcher, M. L., Bozhilov, K. K., Sasaki, K. 2026; 40 (8): e70641

  Abstract

  Normothermic regional perfusion (NRP) is associated with improved posttransplant outcomes in donation after circulatory death (DCD) kidney transplantation. It remains unknown whether hypothermic machine perfusion (HMP) offers additional benefits over static cold storage (SCS) during transport.All adult kidney-only transplantations from DCD donors procured by NRP in the OPTN data (10/1/2020-6/30/2025) were identified. Primary exposure was preservation method during transport: NRP combined with HMP (NRP+HMP) or SCS (NRP+SCS). One-to-two propensity score matching (PSM) was performed on fifteen donor and recipient factors. Primary outcomes included delayed graft function (DGF), posttransplant length of stay (LOS), and estimated glomerular filtration rate (eGFR) at 6 months posttransplant. Secondary outcomes were one-year graft and patient survival.Among 4792 NRP cases, HMP was utilized in 85.1%, with its use increasing over time. After 1:2 PSM (685 NRP+SCS matched to 1262 NRP+HMP), NRP+HMP was associated with significantly lower DGF (23.3% vs. 30.5%, p < 0.01). Median LOS (4.0 days in both groups, p = 0.07), 6-month eGFR (58.5 vs. 60.1 mL/min/1.73m2, p = 0.46), one-year graft survival, and one-year patient survival were not significantly different. The association between HMP and lower DGF was observed across KDPI strata, heart recovery status, and cold ischemia time categories, with no significant interactions detected.The adoption of HMP after NRP has increased substantially in the United States and was associated with reduced DGF, but no difference was observed for LOS, 6-month eGFR, graft survival, and patient survival. These findings support the routine use of HMP after NRP.

  View details for DOI 10.1111/ctr.70641

  View details for PubMedID 42599744

  View details for PubMedCentralID PMC13475596

• Undercapture of HeartMate 3-Supported Pediatric Candidates in the OPTN STAR Registry. The Annals of thoracic surgery Ahn, D. J., Attia, A., Nakayama, T., Parker, W. F., Khush, K. K. 2026

  View details for DOI 10.1016/j.athoracsur.2026.06.066

  View details for PubMedID 42468869

• Potential Impact of the OPTN Status Escalation Policy for Adult Heart Transplant Candidates With Durable LVADs. Circulation. Heart failure Ahn, D. J., Attia, A., Nakayama, T., Narang, N., Khush, K. K., Parker, W., Sasaki, K. 2026: e013854

  Abstract

  The 2018 heart allocation policy change substantially lowered the priority of candidates supported with durable left ventricular assist devices (LVADs) for heart transplantation. To provide stable candidates supported by durable LVADs with a quicker path to transplantation before they suffer complications, the Organ Procurement and Transplantation Network (OPTN) approved a policy stipulating that stable patients supported by durable LVADs for 6 and 8 years will obtain statuses 3 and 2, respectively.Using OPTN data, we identified all adult heart transplant candidates with a durable LVAD implanted between October 18, 2018 and May 31, 2025. We estimated the cumulative incidence of LVAD-related complications, treating transplantation and waitlist removal before experiencing complications as competing events. Furthermore, we assessed how the OPTN policy change would impact the status distribution of the waitlist.In our study cohort, 4967 adult patients who were listed for heart transplant received a durable LVAD. Transplant centers submitted 2879 justifications for status upgrades due to LVAD-related complications for 1812 (36.5%) patients. At 6 years after durable LVAD implantation, the cumulative incidence of complications and status upgrades was 42.1% (95% CI, 40.5%-43.8%), and that of transplantation was 36.0% (95% CI, 34.6%-37.6%). Of the 3779 patients who were not censored administratively, only 47 (1.2%) remained on the waitlist by 6 years after durable LVAD implantation. Had the 6- to 8-year OPTN policy change been implemented on June 1, 2025, only 4.7% of the waitlist would have changed statuses instantaneously.Almost all listed candidates with durable LVADs either experience a complication, status upgrade or are removed from the waitlist within 6 years of obtaining a durable LVAD. The upcoming OPTN policy is unlikely to prevent device complications before granting status upgrades and will likely impact a small percentage of candidates with durable LVADs.

  View details for DOI 10.1161/CIRCHEARTFAILURE.125.013854

  View details for PubMedID 42335275

  View details for PubMedCentralID PMC13293278

• High Rate of Transplantation Before Review of Status Exception Requests Among Adult Heart Transplant Candidates. Circulation. Heart failure Ahn, D. J., Nakayama, T., Attia, A., White, M., Eap, D., Narang, N., Khush, K. K., Parker, W. F., Sasaki, K. 2026: e013994

  Abstract

  In the US heart allocation system, when transplant centers submit applications for status exceptions to increase waitlist priority, patients obtain the requested status upgrades immediately while their applications are sent to the regional review boards (RRBs) and reviewed retrospectively. How often transplants occur during this period is unknown.Using the Scientific Registry of Transplant Recipients, we identified all adult heart transplant candidates listed between October 18, 2018, and May 31, 2025, with submitted applications for status exceptions. We assessed (1) the time elapsed between submission of exception applications and their receipt by the RRBs and (2) the rate of heart transplantation during this travel time, stratified by whether the applications were eventually approved or denied. Additionally, we estimated how many listed patients were skipped by candidates who received transplants with exceptions that were ultimately denied.138 transplant centers submitted status exception requests on behalf of 11 508 adult candidates during the study period, of whom 913 (7.9%) received a denial at least once. The median time from obtaining status upgrades to application receipt by the RRBs was 3 days. Three thousand seven out of 11 508 (26.1%) patients received transplants before the RRBs even received their applications, with 174 (19.1%) among 913 with eventual denials and 2833 (26.7%) among 10 595 with approvals. The cumulative incidence of heart transplantation before application receipt for eventual denials was 19.1% (95% CI, 16.6%-21.7%), and that for approvals was 27.2% (95% CI, 26.4%-28.0%; P<0.001) at 2 weeks. Candidates who received transplants despite being denied exceptions bypassed more than 11 thousand potential transplant recipients.More than 25% of patients with status exception requests receive heart transplants before their applications are even received by their RRBs, raising significant concerns about the fairness of retrospective review of exception requests for the allocation of donor hearts.

  View details for DOI 10.1161/CIRCHEARTFAILURE.125.013994

  View details for PubMedID 42329622

  View details for PubMedCentralID PMC13288750

• Artifactual Declines in Durable LVAD Utilization among Heart Transplant Candidates: Selection Bias in Transplant Registries. The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation Ahn, D. J., Lyden, G. R., Attia, A., Nakayama, T., Narang, N., Sasaki, K., Parker, W. F., Khush, K. K. 2026

  Abstract

  The Organ Procurement and Transplantation Network (OPTN) Standard Transplant Analysis and Research (STAR) files are commonly used to study use of mechanical circulatory support (MCS) among heart transplant candidates. However, the STAR MCS file reports devices only for candidates removed from the waitlist, whereas the Scientific Registry of Transplant Recipients (SRTR) MCS file includes devices for all candidates. We compared the STAR and SRTR MCS files in estimating trends in LVAD support and waitlist outcomes among heart transplant candidates with durable LVADs.We identified adult heart transplant candidates who obtained durable LVADs between October 18, 2018 and December 31, 2024 using MCS files from STAR (N=4,182) and SRTR (N=4,919). We estimated the cumulative incidence of transplantation and death/deterioration in both cohorts and analyzed LVAD prevalence at bimonthly intervals from October 2018 to April 2025.The SRTR cohort showed stable LVAD prevalence (30.7%-37.4%). In contrast, the STAR cohort constructed from the MCS file showed a 92.5% decline in LVAD prevalence (1,740 to 131 candidates), despite 971 candidates listed with status 4 for LVAD support on April 30, 2025. The STAR cohort demonstrated higher 3-year cumulative incidence of transplantation (66.7% vs 54.4%) and death/deterioration (10.1% vs 4.5%) after LVAD implantation. When we reran STAR-based analyses with both MCS and status justification files, prevalence and outcomes matched SRTR estimates.The STAR MCS file excludes LVADs among currently listed candidates, producing artifactual declines in LVAD prevalence and incidence and inflated waitlist outcomes. Awareness of registry construction is essential for accurate interpretation of LVAD-related outcomes.

  View details for DOI 10.1016/j.healun.2026.06.002

  View details for PubMedID 42263896

• Donor Warm Ischemia Time Modifies Susceptibility to Cold Ischemia in Donation After Circulatory Death Kidney Allografts Under Hypothermic Machine Perfusion. Transplantation Nakayama, T., Attia, A., Ahn, D. J., Endo, Y., Kashyap, R. S., Hernández-Alejandro, R., Sasaki, K., Bekki, Y. 2026

  Abstract

  Donation after circulatory death (DCD) kidneys are exposed to donor warm ischemia time (dWIT) in addition to cold ischemia. Although porcine studies suggest synergy between these insults, evidence in clinical transplantation is limited.Adult DCD kidney-only transplants performed using hypothermic machine perfusion (n = 28 698) in the United Network for Organ Sharing database (January 1, 2015, to December 31, 2023) were included. We performed 1:1:1 propensity score matching across 3 cold ischemia time (CIT) categories (short, <18 h; intermediate, 18-23 h; and long, ≥24 h) on the Kidney Donor Profile Index and estimated posttransplant survival. The incidence of delayed graft function and 5-y graft survival was evaluated in the matched cohort (6885 per group) and subgroups of dWIT (≤30, 31-45, and ≥46 min).CIT categories stratified 5-y graft survival: 76.1% in short CIT, 73.9% in intermediate CIT, and 72.1% in long CIT. Compared with short CIT group, recipients in the long CIT (≥24 h) group had higher hazards of graft loss across dWIT subgroups (for dWIT ≤30 min: hazard ratio [HR], 1.11 [95% confidence interval (CI), 1.01-1.22]; for dWIT 31-45 min: HR, 1.31 [95% CI, 1.10-1.56]; and for dWIT ≥46 min: HR, 1.56 [95% CI, 1.25-1.93]). A similar interaction was observed for delayed graft function incidence.Prolonged dWIT increases DCD kidney susceptibility to CIT, and DCD kidneys with dWIT ≥46 min resulted in detrimental graft survival when CIT exceeds ≥24 h. For DCD kidney transplantation using hypothermic machine perfusion, CIT should be minimized in kidneys with prolonged dWIT.

  View details for DOI 10.1097/TP.0000000000005758

  View details for PubMedID 42204398

• Highly Sensitized Pediatric Kidney Candidates Have Reduced Access to Kidney Transplant in the United States. American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons Nakayama, T., Ahn, D. J., Attia, A., Bozhilov, K. K., Kirchner, V. A., Sasaki, K., Busque, S., Melcher, M. L., Pham, T. A. 2026

  Abstract

  Kidney transplantation is prioritized for children in the United States, yet equity for highly sensitized pediatric candidates remains uncertain. Using Organ Procurement and Transplantation Network data, we examined kidney-only candidates aged 0-17 years listed between December 4, 2014 and December 31, 2024 who were ever activated, comparing the Kidney Allocation System (KAS; Era 1) and the 2021 circle-based revision (KAS250; Era 2). Candidates were stratified by calculated panel-reactive antibody (cPRA) at first activation (0-20%, 21-79%, 80-99%, 100%). The primary outcome was 3-year cumulative incidence of deceased-donor kidney transplant (DDKT) in competing-risk analysis. Among 7,215 activated pediatric candidates, highly sensitized candidates accepted organs from greater distances. In both eras, candidates with cPRA 80-99% (Era 1: SHR 0.46, 95%CI 0.36-0.59; Era 2: SHR 0.53, 95%CI 0.42-0.67) and cPRA 100% (Era 1: SHR 0.28, 95%CI 0.16-0.48; Era 2: SHR 0.28, 95%CI 0.18-0.43) had persistently reduced access to DDKT (all p<0.001). While non-sensitized candidates had higher DDKT rates than adults, those with cPRA 80-99% or 100% had similar rates to adults. Findings suggest that pediatric prioritization does not fully extend to highly sensitized children, supporting the need for broader sharing.

  View details for DOI 10.1016/j.ajt.2026.05.008

  View details for PubMedID 42142590

• Current status of split liver transplantation using machine perfusion in the United States. HPB : the official journal of the International Hepato Pancreato Biliary Association Nakayama, T., Ito, R., Attia, A., Ahn, D. J., Ichida, H., Shiraki, S., Sasaki, K. 2026

  View details for DOI 10.1016/j.hpb.2026.04.465

  View details for PubMedID 42156276

• Out-of-Sequence or Out of Options? Rethinking Liver Allocation in a Crisis of Confidence. American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons Attia, A., Sasaki, K., Kwong, A. J. 2026

  View details for DOI 10.1016/j.ajt.2026.02.029

  View details for PubMedID 41771356

• Status Exceptions and Misalignment of Medical Urgency in U.S. Pediatric Heart Transplantation. Journal of the American College of Cardiology Ahn, D. J., Attia, A., Nakayama, T., Narang, N., Daly, K., Khush, K. K., Parker, W. F., Sasaki, K. 2026

  Abstract

  Pediatric heart transplant candidates experience high waitlist mortality, in part because of limited availability of appropriate donor hearts. Transplant physicians can request status exceptions to increase priority for candidates, but this practice may contribute to overcrowding of high-priority statuses. In 2021, the National Heart Review Board (NHRB) was established to standardize exception review, but its impact remains unknown.The goal of this study was to determine whether exceptions are granted to children at high risk of death on the waitlist and the impact of the NHRB on outcomes.Using Organ Procurement and Transplantation Network data, we identified all pediatric heart transplant candidates listed March 2016 through March 2025. We estimated the association between status exceptions and waitlist mortality using mixed-effects Cox proportional hazards models and compared concordance indices for the current system vs a hypothetical system without exceptions.Among 6,026 candidates, 745 (12.4%) died or deteriorated and 1,668 (27.7%) received exceptions. Exception recipients had a significantly lower waitlist mortality risk than standard criteria patients (HR: 0.41; 95% CI: 0.31-0.55; P < 0.001) and the NHRB's impact on this association was nonsignificant (P = 0.62). We observed significant heterogeneity in waitlist mortality within status 1A, with exception recipients having the highest survival. When modeling waitlist mortality, the concordance index improved from 0.694 (95% CI: 0.682-0.706) with exceptions to 0.713 (95% CI: 0.700-0.724) without exceptions (P < 0.001).Pediatric heart transplant candidates granted status exceptions have significantly lower medical urgency than those meeting standard criteria. Implementation of a national review board did not result in improved alignment between waitlist mortality and listing status.

  View details for DOI 10.1016/j.jacc.2026.01.052

  View details for PubMedID 41778948

• Potential Double Counting in Meta-Analysis of Combined Heart-liver Transplantation. Transplantation Nakayama, T., Attia, A., Ahn, D. J., Sasaki, K. 2026

  View details for DOI 10.1097/TP.0000000000005642

  View details for PubMedID 41604423

• Current status of minimally invasive liver transplantation: a narrative review ANNALS OF LAPAROSCOPIC AND ENDOSCOPIC SURGERY Nakayama, T., Attia, A., Ahn, D. J., Sasaki, K., Margonis, G. 2026; 11

  View details for DOI 10.21037/ales-2025-1-52

  View details for Web of Science ID 001686821200008

• Donor-Recipient Age Mismatch and Long-Term Graft Outcomes After Adolescent Liver Transplant. JAMA network open Nakayama, T., Jensen, A. R., Attia, A., Ahn, D. J., Firl, D. J., Kwong, A., Charu, V., Melcher, M. L., Esquivel, C. O., Sasaki, K. 2026; 9 (1): e2552779

  Abstract

  Importance: Donor-recipient age mismatch is an established risk factor in adult liver transplants (LTs), yet its effect in adolescents, who require long-term graft durability, has not been fully characterized. Despite pediatric prioritization, some adolescent donor livers are allocated to adults, limiting access to age-matched grafts for adolescents.Objective: To assess whether a donor-recipient age difference of 10 or more years is associated with inferior graft survival in LTs among adolescents and to estimate the benefits of broader geographic sharing of adolescent donor livers.Design, Setting, and Participants: This retrospective, registry-based case-control study used data from the Organ Procurement & Transplantation Network database, a nationwide US transplant registry. Participants were adolescents aged 12 to 17 years who received liver-only grafts from donation after brain death between March 1, 2002, and December 31, 2024, with follow-up until April 4, 2025. Propensity score matching (1:1) was performed on graft type and size mismatch, donor sex, donor-recipient sex mismatch, transplant center volume, and recipient variables.Exposure: Donor-recipient age difference of 10 or more years (age-mismatched graft) vs less than 10 years (age-matched graft).Main Outcomes and Measures: The primary outcome was 10-year graft survival. The secondary outcome was 10-year overall survival. Waiting time to an age-matched graft offer under alternative donor-sharing radii (1500 nautical miles [NM], 1000 NM, or no limit vs 500 NM) were also estimated.Results: Among 2020 adolescents receiving LTs (median age, 15.0 [IQR, 13.0-16.0] years; 1081 [53.5%] female), 612 (30.3%) received age-mismatched grafts (median donor age, 36.0 [IQR, 29.0-45.0] years) and 1408 (69.7%) received age-matched grafts (median donor age, 16.0 [IQR, 13.0-17.0] years). The age-mismatched group had a higher proportion of recipient candidates in the intensive care unit at transplant (287 [46.9%] vs 250 [17.8%]; P<.001). After propensity score matching (n=526 per group), 10-year graft survival was 61.5% in the age-mismatched group and 74.2% in the age-matched group (P<.001), with consistent results across recipients' pretransplant hospitalization status. A simulation estimated that expanding the adolescent allocation radius to 1000 NM would allow 90% of adolescent candidates to receive age-matched offers within 15 days, compared with 44 days under the current 500-NM limit.Conclusions and Relevance: In this case-control study of a US national cohort of adolescents receiving LT, donor-recipient age mismatch of 10 or more years was associated with inferior graft survival. Broader allocation of adolescent donors may improve access to age-matched grafts and long-term outcomes.

  View details for DOI 10.1001/jamanetworkopen.2025.52779

  View details for PubMedID 41499116

• Highly Sensitized Pediatric Kidney Candidates Have Reduced Access to Kidney Transplant Following the Implementation of Donor Concentric Circle Allocation Nakayama, T., Ahn, D., Attia, A., Sasaki, K., Pham, T. ELSEVIER SCIENCE INC. 2026

  View details for Web of Science ID 001684210000061

• Use of Non-Standardized Exceptions among Pediatric Liver Transplant Candidates in the PELD vs PELD-Cr Eras Ahn, D., Nakayama, T., Attia, A., Sasaki, K., Pham, T. ELSEVIER SCIENCE INC. 2026

  View details for Web of Science ID 001684522300082

• Initial Experience with Routine Post-Operative Contrast Enhanced Ultrasound Following Pediatric Whole and Partial Deceased Donor Liver Transplant York, T., Attia, A., Nakayama, T., Yu, J., Fu, S., Hanna, K., Ahn, D., Badshah, J., Ebel, N., Alrabadi, L., Czepiel, K., Melcher, M., Pham, K., Busque, S., Rubesova, E., Kirchner, V. ELSEVIER SCIENCE INC. 2026

  View details for Web of Science ID 001684522300010

• When Offers Descend: Pathway, Timing, and Outcomes in Liver Transplantation Attia, A., Nakayama, T., Ahn, D., York, T., Sasaki, K. ELSEVIER SCIENCE INC. 2026

  View details for Web of Science ID 001684210000071

• Association between volume and outcomes in pediatric kidney transplantation Fu, S., Nakayama, T., Ahn, D., Attia, A., Sasaki, K., Pham, T. ELSEVIER SCIENCE INC. 2026

  View details for Web of Science ID 001684210000043

• Renal Resistance on Hypothermic Machine Perfusion and Acceptance of Deceased Donor Kidney Allografts. Journal of the American Society of Nephrology : JASN Nakayama, T., Attia, A., Ahn, D. J., McCabe, M., Endo, Y., Kashyap, R. S., Pham, T. A., Melcher, M. L., Sasaki, K., Bekki, Y. 2025

  View details for DOI 10.1681/ASN.0000000986

  View details for PubMedID 41563235

• Complications and Status Upgrades among Adult Heart Transplant Candidates with Durable LVADs: Waiting 6 to 8 Years for Status Escalation Is Too Long. medRxiv : the preprint server for health sciences Ahn, D. J., Attia, A., Nakayama, T., Narang, N., Khush, K. K., Parker, W., Sasaki, K. 2025

  Abstract

  Introduction: After the 2018 allocation policy change, the rate of listings and transplants with durable LVADs has decreased significantly in favor of bridging patients from temporary mechanical circulatory support to heart transplant. The Organ Procurement and Transplantation Network (OPTN) recently approved a policy, to be implemented in September 2026, stipulating that patients supported by durable LVADs for 6 and 8 years will obtain statuses 3 and 2, respectively.Methods: Using OPTN data, we identified all adult heart transplant candidates with a durable LVAD implanted between October 18, 2018 and May 31, 2025. We estimated the cumulative incidence of status upgrades and durable LVAD-related complications, treating transplantation and waitlist removal before experiencing complications as competing events. We also assessed how the composition of the adult heart transplant waitlist on June 1, 2025 would have changed based on the upcoming policy change.Results: During the study period, 3,881 adult patients were listed for heart transplant with a durable LVAD. 3,182 (82.0%) of the durable LVADs were Abbott HeartMate 3, 568 (14.6%) were Medtronic Heartware HVAD, and 91 (2.3%) were Abbott HeartMate II. Transplant centers submitted a total of 6,924 justifications for status upgrades due to LVAD-related complications (6.3% status 1, 34.3% status 2, and 59.4% status 3) for 1,500 (38.6%) of these patients, with a median of 3 per patient. The cumulative incidence of complications or status upgrades was 38.6% [95% CI (37.1%, 40.2%)]. Nearly all of the 2,381 patients who did not experience any complication or status upgrade during listing were removed from the waitlist by 6 years. Had the upcoming OPTN policy change been implemented on June 1, 2025, the proportion of the waitlist that would have achieved higher priority status instantaneously was 0.06%.Conclusions: The cumulative incidence of status upgrades and complications among heart transplant candidates with durable LVADs was nearly 40% within 6 years of device implantation. The upcoming OPTN policy to escalate patients to statuses 3 and 2 after 6 and 8 years of durable LVAD support, respectively, is unlikely to make a meaningful impact on waitlist priority status.

  View details for DOI 10.1101/2025.09.22.25336215

  View details for PubMedID 41040709

• High Rate of Transplantation Prior to Review of Status Exception Requests among Adult Heart Transplant Candidates. medRxiv : the preprint server for health sciences Ahn, D. J., Nakayama, T., Attia, A., White, M., Eap, D., Narang, N., Khush, K. K., Parker, W., Sasaki, K. 2025

  Abstract

  In the United States heart allocation system, when transplant centers submit applications for status exceptions to increase waitlist priority, patients obtain the requested status upgrades immediately while their applications are sent to the regional review boards (RRBs) and reviewed retrospectively. How much time elapses between obtaining a status upgrade through exception and application receipt by the RRBs and how often transplants occur during this period is unknown.Using the Scientific Registry of Transplant Recipients (SRTR), we identified all adult heart transplant candidates listed between October 18, 2018 and December 31, 2023 with submitted applications for status exceptions. We assessed 1) the amount of time elapsed between submission of exception applications and their receipt by the RRBs and 2) the rate of heart transplantation during this "travel" time, stratified by whether the applications were eventually approved or denied. Additionally, using complete match run data, we estimated how many listed patients were skipped by candidates who received transplants with exceptions that were ultimately denied.135 transplant centers submitted status exception requests on behalf of 8,269 adult candidates during the study period, of whom 608 (7.4%) received a denial at least once. The median time from obtaining higher priority statuses immediately via exceptions to application receipt by the RRBs was 3 days. 2,087 out of 8,269 (25.2%) patients received transplants before the RRBs even received their applications, with 115 (18.9%) among 608 with eventual denials and 1,972 (25.7%) among 7,661 with approvals. The cumulative incidence of heart transplantation before application receipt for eventual denials was 19.1% (95% CI [16.0%, 22.3%]) and that for approvals was 26.2% (95% CI [25.2%, 27.1%]) (p < 0.001) at 2 weeks. Based on match run data, the 115 patients who received transplants with denied exceptions bypassed more than seven thousand potential transplant recipients.More than 25% of patients with status exception requests receive heart transplants before their applications are even received by their respective RRBs, let alone reviewed. This raises significant concerns about the efficacy and fairness of retrospective review of exception requests for the allocation of valuable donor hearts.

  View details for DOI 10.1101/2025.09.12.25335606

  View details for PubMedID 41001456

  View details for PubMedCentralID PMC12458605

• UK liver transplantation allocation algorithm: transplant benefit score - Authors' reply. Lancet (London, England) Stutchfield, B. M., Attia, A., Rowe, I. A., Harrison, E. M., Gordon-Walker, T. 2023; 402 (10399): 371-372

  View details for DOI 10.1016/S0140-6736(23)01307-7

  View details for PubMedID 37516542

• Management of temporary epicardial pacing wires in the cardiac surgical patient BRITISH JOURNAL OF HOSPITAL MEDICINE Francis, J., Prothasis, S., Hegde, R., Attia, A., Buchan, K. 2021; 82 (6): 1-7

  Abstract

  Temporary epicardial pacing wires are used after cardiothoracic surgery to maintain a stable cardiac rhythm. They must be distinguished from the more commonly encountered transvenous temporary pacing wires, which are often used in coronary care units for the same purpose. Patients with temporary epicardial pacing wires may be transferred to hospital wards where these wires are not usually encountered, such as COVID wards, the general intensive care unit, the coronary care unit or general surgical wards if a laparotomy was required in the early period following cardiac surgery. Serious complications may arise in managing patients with temporary epicardial pacing wires, which are well known in the cardiothoracic unit but not so well known elsewhere in the hospital. This article discusses the dangers associated with the management of temporary epicardial pacing wires in adult patients, some of which are common to temporary transvenous pacing wires and others are unique to temporary epicardial pacing wires.

  View details for DOI 10.12968/hmed.2021.0079

  View details for Web of Science ID 000669782800014

  View details for PubMedID 34191570