Haney, John C.

Abstract Rationale Acute cellular rejection (ACR) within first-year post-lung transplantation has important implications for prognosis. Calcineurin inhibitors (CNI), including tacrolimus or cyclosporine, along with cell cycle inhibitors (CCI) and steroids, remain the standard immunosuppression regimen post-transplant. Although tacrolimus is used as the primary CNI, target therapeutic levels vary across recipients due to adverse effects and tolerability, sometimes requiring switching over to Cyclosporine. We hypothesized that ACR within the first year is associated with switching CNI from Tacrolimus to Cyclosporine. Methods We performed a cross-sectional study of 255 adult lung transplant recipients between June 2019 to November 2024 at Mayo Clinic, Florida. Demographics, induction regimens, CNI type and their levels (average low and high levels) were compared between the 2 groups. The institutional maintenance immunosuppression regimen is Tacrolimus, Mycophenolate Mofetil (MMF) and prednisone, but could be switched to Cyclosporine if the previous regimen is not tolerated. The primary outcome was ACR <1 year diagnosed based on biopsy and/or clinical criteria. Comparisons between groups were performed using Chi-Square test for categorical variables and t-test or Wilcoxon Rank sum test for continuous variables. Multivariable regression analysis was performed with ACR <1 year as the outcome to adjust for the confounders. Results Our cohort included 255 lung transplant recipients with median age of 63 years, 61% Male, 84% Caucasians, 88% bilateral lung transplant (Further details elucidated in Table 1). A total of 173 (67%) out of 255 patients had ACR <1 year. The group with ACR < 1 year had higher proportion of Interstitial Lung Disease (ILD) (81% vs 68%, p = 0.044), use of Basiliximab for induction (70% vs 55%, p = 0.018), and cyclosporine instead of tacrolimus (23% vs 11%, p = 0.027). Group with ACR <1 year also had higher Antibody Mediated Rejection (AMR) < 1year (15% vs 6.1%, p = 0.041) and higher CLAD (BOS 0p-3: 43% vs 25.6%, p = 0.033) compared to the group without ACR < 1 year (Table 1.1). Multivariate regression analysis showed ILD (adjusted odds ratio, aOR 2.84, 95% CI 1.31 - 6.27, p = 0.008) and use of cyclosporine (aOR 2.55, 95% CI 1.07 - 6.78, p = 0.034) as independent predictors of ACR < 1 year (Table 2). Conclusions The presence of ACR < 1 year was associated with the use of Cyclosporine over Tacrolimus as a maintenance regimen. Also, ACR < 1year was associated with higher AMR and CLAD. Further prospective studies are needed to study this long-term given its significant prognostic implications. This abstract is funded by: Not Applicable

ABSTRACT Background Treating Mycobacterium avium complex (MAC) infection pre‐lung transplant (LT) can be challenging to treat, given prolonged therapy and side effects. The impact of pre‐transplant MAC treatment on recurrence and outcomes post‐LT remains unclear, especially in patients with interstitial lung disease (ILD) who have a median survival of less than 2 years. Methods We performed a retrospective cohort study of adult LT patients at the Mayo Clinic who had positive MAC sputum cultures pre‐LT. The cohort was stratified and compared based on the type of treatment (complete, partial, or no treatment) for MAC pulmonary infection. The primary outcome was MAC recurrence post‐LT, and secondary outcomes were mortality, FEV‐1, and FVC at 1‐year post‐LT. Results Among the cohort of 47 patients, 9 (19.1%) were partially treated and 11 (23.4%) were completely treated for MAC infection pre‐LT. Post‐transplant MAC pulmonary infection recurrence occurred in eight (17%) of the total cohort, with four (14.8%) in the non‐treated, four (44.4%) in the partially‐treated, and none (0%) in the completely treated patients ( p = 0.026). There was no difference in mortality in patients who had MAC recurrence post‐transplantation (13% vs. 9.7%, p > 0.9) and those who were completely or partially treated, compared to non‐treated (0% vs. 13% vs. 13%, p > 0.9). The FEV1 and FVC at 1‐year post‐LT did not differ by the pre‐transplant treatment or post‐transplant MAC recurrence status. Conclusion The role of treatment for MAC infection pre‐transplant is questionable, especially in patients with diseases like ILD who may not have enough wait time to complete therapy.

Extracorporeal membrane oxygenation (ECMO) use during liver transplantation is a complex and evolving aspect of critical care. This retrospective analysis presents the largest North American case series to date, offering a detailed comparison of survival outcomes in liver transplant (LT) patients supported by ECMO. A total of 15 patients were supported with ECMO, eight were supported on venoarterial (VA) ECMO and the remaining seven on venovenous (VV) ECMO. The median duration of ECMO support was 10 days. Mean intensive care unit (ICU) and hospital stays were 34.8 (interquartile range [IQR]: 1–158) and 49.2 days (IQR: 1–121), respectively. Overall survival was 33.3%, comparable to published rates (20–30%). Survival was based on ECMO initiation timing: preoperative 33.3% (1/3); intraoperative 50% (3/6); postoperative, 16.6% (1/6). All the patients (five) discharged from hospital were alive at 1 year follow-up. Significant ECMO-related complications included acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT) (40%, n = 6/15), neurological complications (40%, n = 6/15), and bleeding requiring transfusion (26.6%, n = 4/15). Literature review suggests better outcomes with intraoperative or postoperative ECMO. While ECMO use is increasing in LT, outcomes remain poor. Improved survival may depend on careful patient selection, optimal timing of initiation, and distinguishing reversible pathology from irreversible one.

Introduction: Cardiopulmonary bypass time (CPBT) and aortic cross-clamp time (AXCT) are independently associated with postoperative morbidity and mortality. However, no universally accepted “optimal” duration exists, as these times are influenced by the complexity of cardiac surgery. ECMO is being increasingly used for cardiogenic shock in patients undergoing cardiotomy, but the impact of CPBT and AXCT on outcomes in this specific population remains unexplored. This study investigates how CPBT and AXCT influence outcomes in cardiotomy patients on ECMO support. Research Question: Do CPBT and AXCT influence mortality and complication rates in cardiotomy patients receiving ECMO support? Methods: We conducted a retrospective chart review (Jan 2020–Dec 2024) across a multidisciplinary North American practice, identifying 623 patients who required ECMO. Of these, 236 (37.8%) received ECMO in the preoperative, intraoperative, or postoperative period of cardiotomy. Patients were grouped by prolonged CPBT (>150 min) vs standard (≤150 min) and prolonged AXCT (>90 min) vs standard (≤90 min). We analyzed outcomes including 30-day mortality, ECMO characteristics, and postoperative complications. Results: Among the 236 patients, the average age was 60.8 years, BMI 37.43 kg/m 2 ; 63% were male, 85% White. Prolonged CPBT and AXCT were associated with higher BMI (p=0.02, 0.03), prior cardiac surgery (p<0.001, 0.006), and combined CABG+AVR procedures (p=0.01, 0.001). Patients with prolonged durations were more likely to require postoperative ECMO (p=0.001, 0.03). Complications such as mediastinal bleeding, AKI requiring CRRT, mediastinitis, bacteremia, and pneumonia, showed significant association with increased CPBT whereas prolonged AXCT was only linked with mediastinal bleeding. CPBT and AXCT durations did not significantly affect 30-day mortality, ICU/hospital stay, ECMO duration, or ventilation duration. Independent predictors of 30-day mortality included pre-/intraoperative IABP use (OR 2.19, 95% CI 1.11–4.30, p=0.023), Impella use (OR 0.20, 95% CI 0.03–0.75, p=0.040), post-op intracranial bleeding (OR 5.46, 95% CI 1.43–23.9, p=0.016), and CRRT-requiring AKI (OR 3.24, 95% CI 1.63–6.57, p<0.001). Conclusion: Prolonged CPBT and AXCT were significantly linked to higher rates of postoperative complications such as mediastinal bleeding, CRRT requiring AKI, mediastinitis, and pneumonia along with increased need for postoperative ECMO support, without significantly affecting mortality.

Background: Heart transplantation is the definitive treatment of end-stage heart failure and is a complex process involving coordination in procurement, preservation, and transport of a donor organ to a recipient. There are different heart transport methods, including the traditional static methods of Cooler and Ryobi and advanced dynamic methods, including SherpaPak and the Organ Care System (OCS). The aim of the study is to compare the post-transplant outcome of these in patients bridged with Impella 5.5. Method: A retrospective study was conducted between 2020 and 2025 after IRB approval. Patient demographics and clinical data was extracted from the medical record. Cox proportional hazards regression model was applied to identify independent predictors of mortality across 30-day, 90-day, and 1-year intervals. Results: 123 patients were included in the analysis. Age, EF and Race were similar between all groups. The transport method was a significant predictor of 1-year mortality. Use of OCS (HR=0.022, p value <0.05) and SherpaPak (HR=0.066, p value <0.05) was associated with a significant decrease in mortality compared to traditional cooler use. Across 30-day, 90-day, and 1-year intervals, OCS showed the strongest survival benefit, while SherpaPak also demonstrated reduced mortality, but less significant compared to OCS. Conclusion: Transport method is a strong predictor of 1-year post-transplant mortality, with OCS showing the most pronounced effect in reducing the risk of 1-year mortality as well as mortality across 30-day and 90-day intervals. These findings support broader adoption of advanced transport systems in clinical practice to improve post-transplant outcomes.

Heart transplantation is a well-established treatment for end-stage heart failure, but many patients present in poor physical condition, complicating outcomes. The Impella 5.5 device, used in cardiogenic shock, may support pretransplant rehabilitation by stabilizing organ function and promoting functional improvement. This retrospective cohort study assessed the relationship between functional status, measured by standardized Activity Measure for Post-Acute Care Basic Mobility (AM-PAC) scores, and days alive outside the hospital within 30 days post-transplant (DAOH-30). Patients who received Impella 5.5 support before transplantation between January 2019 and October 2023 were included, excluding those without AM-PAC scores within 24 hours pretransplant. Among 65 patients, the median DAOH-30 was 15 days (interquartile range [IQR], 8–19). Higher pretransplant standardized AM-PAC scores correlate with increased DAOH-30 (adjusted coefficient 0.3; 95% confidence interval [CI] = 0.01–0.6; p = 0.04), as did AM-PAC score improvement during rehabilitation (adjusted coefficient 0.35; 95% CI = 0.01–0.6; p = 0.04). Extended rehabilitation was associated with greater functional gains. These findings suggest that better pretransplant functional status and rehabilitation-related improvements were associated with increased DAOH-30. The Impella 5.5 device facilitates rehabilitation and may enhance post-transplant outcomes. Further research should refine strategies to optimize rehabilitation and recovery in this high-risk population.

Abstract Introduction: The data on outcomes comparing lung transplantation with ABO-identical versus ABO-compatible blood group is limited. Composite Allocation Score(CAS) was introduced on March 9th, 2023, and has considered additional points for the difficult-to-match blood group. We aimed to study the trend and outcomes of patients who underwent lung transplants with ABO identical versus compatible blood groups. Methods: We queried the United Network of Organ Sharing (UNOS) database of those who underwent lung transplantation between 10/1/1987 to 3/31/2024 and compared the outcomes between those who had ABO-identical vs ABO-compatible blood groups. Combined organ transplants and recipients age &lt;18 were excluded. Results: A total of 50,406 patients were included in our study, out of which 4,111 (8.15%) were ABO-compatible and 47,347 (91.85%) were ABO-identical. Among the recipient demographics, the ABO-compatible group compared to the ABO-identical group showed a lesser lung allocation score (40 ± 16 vs 42 ± 16), but higher A-blood group (59% vs 38%), obstructive lung disease (38% vs 33%), CAS (49 ± 13 vs 47 ± 10), mechanical ventilator support pre-transplant (6.2% vs 5.2%), need for ex-vivo lung perfusion (9.6% vs 5.8%) and listing for single lung transplant (39% vs 34%), all p&lt;0.05. The donors for the ABO-compatible group had a closer distance to the transplant center (205 ± 285 vs 226 ± 265 nautical miles), lesser white race (61% vs 64%), and gender mismatch (30% vs 32%) but higher male gender (64% vs 61%), O-blood group (81% vs 49%) and ethnicity mismatch (45% vs 41%), all p&lt;0.05. The univariate analysis showed a higher 30-day (7.2% vs 5.8%), 1-year (22% vs 19%), and 5-year (54% vs 50%) mortality among patients with ABO-compatible compared to ABO-identical recipients, all p&lt;0.001. However, the adjusted odds ratio of 30-day (0.76, 95% CI 0.36-1.47, p=0.4), 1-year (1.07, 95% CI 0.69-1.66, p=0.7) and 5-year (0.69, 95% CI 0.46-1.05, p=0.081) mortality were not statistically significant with ABO-identical when compared to ABO-compatible group on adjusting to the covariates in the multivariate analysis. The trend of ABO-compatible lung transplantation has been increasing with the introduction of CAS (figure 1). Conclusion: Patients who underwent lung transplantation with the ABO-compatible blood group donor organs had similar outcomes compared to the ABO-identical blood group. The findings of our study reinforce the importance of increasing the use of ABO-compatible organs to enhance the lung transplantation rate, aligning with the observed trend following the introduction of CAS.

Background: Static ice storage (SIS) has long been accepted as the conventional lung preservation method, assuming to maintain 4 °C temperature. Although never directly confirmed by temperature measurements, this assumption has been widely accepted. We aimed to measure lung and preservation temperature with SIS in porcine experiments and clinical observations. Methods: Porcine lungs were preserved with SIS for 8 h (group I, n = 3) and 3 h followed by 10 °C storage (group II, n = 3). Tissue (tissueT°), first bag preservation solution (psT°) and second bag saline (salineT°) temperature were monitored. In clinical lungs (n = 4), psT° was monitored during SIS. Surface (surfaceT°) and core (coreT°) temperature were assessed before and after SIS (n = 62). Results: After 4 h in porcine lung group I, average tissueT° was 0.66 °C, psT° was 0.12 °C and salineT° was −0.02 °C. After 3 h in group II, average tissueT° was 1.90 °C, psT° was 0.57 °C and salineT° was 2.33 °C. In clinical observations, psT° was below 4 °C after 9–13 min and 0 °C after 78–267 min. After SIS, median surfaceT° was 1.25 °C (min-max; −3.2–9.2 °C) and coreT° was 1.45 °C (−0.4–4.8 °C). Conclusions: SIS leads to rapid temperature drops below 4 °C, approaching 0 °C within 2–4 h. The post-SIS lung temperature shows considerable variability and does not consistently remain at the commonly assumed 4 °C, posing potential freezing injury to donor lungs.