Long-term air pollution exposure and the risk of primary graft dysfunction after lung transplantation.

BACKGROUND: Primary graft dysfunction (PGD) contributes substantially to both short and long-term mortality after lung transplantation but the mechanisms that lead to PGD are not well understood. Exposure to ambient air pollutants is associated with adverse events during waitlisting for lung transplantation, and chronic lung allograft dysfunction but its association with PGD has not been studied. We hypothesized that long-term exposure of the lung donor and recipient to high levels of ambient air pollutants would increase the risk of PGD in lung transplant recipients. METHODS: Using data from 1428 lung transplant recipients and their donors enrolled in the Lung Transplant Outcomes Group (LTOG) observational cohort study, we evaluated the association between the development of PGD and zip-code based estimates of long-term exposure to six major air pollutants (ozone, nitrogen dioxide, sulfur dioxide, carbon monoxide, PM2.5 and PM10) in both the lung donor and the lung recipient. Exposure estimates used daily EPA air pollutant monitoring data and were based on the geographic centroid of the each subject's residential zip code. Associations were tested in both univariable and multivariable models controlling for known PGD risk factors. RESULTS: We did not find strong associations between air pollutant exposures in either the donor or the recipient and PGD. CONCLUSIONS: Exposure to ambient air pollutants, at the levels observed in this study, may not be sufficiently harmful to prime the donor lung or the recipient to develop PGD particularly when considering the robust associations with other established PGD risk factors.

Is Night Surgery a Nightmare for Lung Transplantation?

Night work is frequently associated with sleep deprivation and is associated with greater surgical and medical complications. Lung transplantation (LT) is carried out both at night and during the day and involves many medical healthcare workers. The goal of the study was to compare morbidity and mortality between LT recipients according to LT operative time. We performed a retrospective, observational, single-center study. When the procedure started between 6 AM and 6 PM, the patient was allocated to the Daytime group. If the procedure started between 6 PM and 6 AM, the patient was allocated to the Nighttime group. Between January 2015 and December 2020, 253 patients were included. A total of 168 (66%) patients were classified into the Day group, and 85 (34%) patients were classified into the Night group. Lung Donors' general characteristics were similar between the groups. The 90-day and one-year mortality rates were similar between the groups (90-days: n = 13 (15%) vs. n = 26 (15%), p = 0.970; 1 year: n = 18 (21%) vs. n = 42 (25%), p = 0.499). Daytime LT was associated with more one-year airway dehiscence (n = 36 (21%) vs. n = 6 (7.1%), p = 0.004). In conclusion, among patients who underwent LT, there was no significant association between operative time and survival.

Pulmonary Capillary Hemangiomatosis as a Rare Underlying Cause of Primary Pulmonary Hypertension: A Case Report in an Adolescent.

Despite its rarity, pulmonary capillary hemangiomatosis (PCH) presents a significant diagnostic challenge. Due to its similarity to other pulmonary vascular diseases, such as pulmonary veno-occlusive disease, it is characterized by abnormal pulmonary capillary proliferation, which is a rare cause of primary pulmonary hypertension. This case was the first reported instance of PCH in Shahid Rajaee Heart Hospital in Tehran, Iran, in 2023, which was confirmed by genetic testing. It highlighted the importance of considering PCH among the differential diagnoses for pulmonary hypertension, even in adolescent patients. The 13-year-old patient's main complaints were progressive exertional dyspnea and chest pain. He had no previous medical history and had not taken any pharmaceutical or herbal medications. Critical clinical findings included a heart murmur, an electrocardiogram revealing right ventricular hypertrophy, and echocardiogram evidence of pulmonary hypertension. The main diagnosis was PCH, as shown by CT findings of pulmonary artery dilatation and diffuse nodular ground glass opacities. Genetic tests indicated pathogenic EIF2AK4 mutations and suspicion of PCH. Therapeutic intervention included vasodilator therapy, which exacerbated the patient's condition. This case emphasized the importance of maintaining a high index of suspicion for rare causes of pulmonary hypertension, such as PCH. The outcome was to prepare the patient for lung transplantation. To differentiate PCH from other pulmonary vascular diseases, a combination of clinical presentation, radiologic studies, genetic analysis, and response to treatment is required to determine appropriate management, particularly lung transplantation.

Hyperacute experimental model of rat lung transplantation using a coronary shunt cannula.

BACKGROUND: Lung transplantation is a well-established treatment of end-stage lung disease. A rodent model is an inexpensive way to collect biological data from a living model after lung transplantation. However, mastering the surgical technique takes time owing to the small organ size. AIM: To conduct rat lung transplantation using a shunt cannula (SC) or modified cannula (MC) and assess their efficacy. METHODS: Rat lung transplantation was performed in 11 animals in the SC group and 12 in the MC group. We devised a method of rat lung transplantation using a coronary SC for coronary artery bypass surgery as an anastomosis of pulmonary arteriovenous vessels and bronchioles. The same surgeon performed all surgical procedures in the donor and recipient rats without using a magnifying glass. The success rate of lung transplantation, operating time, and PaO2 values were compared after 2-h reperfusion after transplantation. RESULTS: Ten and 12 lungs were successfully transplanted in the SC and MC groups, respectively. In the SC group, one animal had cardiac arrest within 1 h after reperfusion owing to bleeding during pulmonary vein anastomosis. The operating time for the removal of the heart-lung block from the donor and preparation of the left lung graft was 26.8 ± 2.3 and 25.7 ± 1.3 min in the SC and MC groups, respectively (P = 0.21). The time required for left lung transplantation in the recipients was 37.5 ± 2.8 min and 35.9 ± 1.4 min in the SC and MC groups, respectively (P = 0.12). PaO2 values at 2 h after reperfusion were 456.2 ± 25.5 and 461.2 ± 21.5 mmHg in the SC and MC groups, respectively (P = 0.63), without difference between the groups. CONCLUSION: A hyperacute rat lung transplantation model using a coronary SC was created using a simple technique. The MC was inexpensive, easy to prepare, and simple to operate.

Pseudomonas aeruginosa infection correlates with high MFI donor-specific antibody development following lung transplantation with consequential graft loss and shortened CLAD-free survival.

BACKGROUND: Donor-specific antibodies (DSAs) are common following lung transplantation (LuTx), yet their role in graft damage is inconclusive. Mean fluorescent intensity (MFI) is the main read-out of DSA diagnostics; however its value is often disregarded when analyzing unwanted post-transplant outcomes such as graft loss or chronic lung allograft dysfunction (CLAD). Here we aim to evaluate an MFI stratification method in these outcomes. METHODS: A cohort of 87 LuTx recipients has been analyzed, in which a cutoff of 8000 MFI has been determined for high MFI based on clinically relevant data. Accordingly, recipients were divided into DSA-negative, DSA-low and DSA-high subgroups. Both graft survival and CLAD-free survival were evaluated. Among factors that may contribute to DSA development we analyzed Pseudomonas aeruginosa (P. aeruginosa) infection in bronchoalveolar lavage (BAL) specimens. RESULTS: High MFI DSAs contributed to clinical antibody-mediated rejection (AMR) and were associated with significantly worse graft (HR: 5.77, p < 0.0001) and CLAD-free survival (HR: 6.47, p = 0.019) compared to low or negative MFI DSA levels. Analysis of BAL specimens revealed a strong correlation between DSA status, P. aeruginosa infection and BAL neutrophilia. DSA-high status and clinical AMR were both independent prognosticators for decreased graft and CLAD-free survival in our multivariate Cox-regression models, whereas BAL neutrophilia was associated with worse graft survival. CONCLUSIONS: P. aeruginosa infection rates are elevated in recipients with a strong DSA response. Our results indicate that the simultaneous interpretation of MFI values and BAL neutrophilia is a feasible approach for risk evaluation and may help clinicians when to initiate DSA desensitization therapy, as early intervention could improve prognosis.

[Outcomes of respiratory rehabilitation program in lung transplant recipients: a quasi experimental study]. / Resultados de un programa de rehabilitación respiratoria en pacientes receptores de trasplante pulmonar: estudio cuasiexperimental.

INTRODUCTION: Lung transplant (LT) is the ultimate option for end-stage lung diseases. Malnutrition and sarcopenia, common in LT recipients, can be reversible with adequate exercise and nutrition. This study aims to assess changes in physical performance and aerobic capacity after a 10-week rehabilitation program (RP) in LT recipients, as well as to describe the prevalence of sarcopenia and malnutrition before and after RP and their influence on clinically relevant outcomes. MATERIALS AND METHODS: Quasi-experimental study, before and after a 10-week PR in first-time TP recipients, aged over 18 years, from January 2022 to September 2023. Aerobic exercise capacity was assessed through the 6-minute walking test (6MWT) and peak oxygen consumption (VO2peak); and physical performance was measured using the Short Physical Performance Battery (SPPB). Additionally, the prevalence of sarcopenia was described according to the criteria of the European Working Group on Sarcopenia in Older People (EWGSOP2) and malnutrition according to the criteria of the Global Leadership Initiative on Malnutrition (GLIM). RESULTS: Of the 41 patients, 56% had sarcopenia and 80% had malnutrition. After RP, the distance walked in the 6MWT increased by 66.3m (p=0.004) in men and 61m (p=0.001) in women. VO2peak increased in men by a mean of 3.1ml/min/kg (p=0.024). Physical performance improved significantly in both men and women according to the Short Physical Performance Battery (SPPB), with clinically relevant differences of 1.6 pts (p<0.001) and 1.2 pts (p=0.012), respectively. The prevalence of sarcopenia decreased to 24% and malnutrition to 61%. CONCLUSIONS: RP proved to be an effective and safe intervention for LT recipients. In addition to improvements in skeletal muscle strength and exercise capacity, a reduction in the prevalence of sarcopenia and malnutrition was also observed.

Prognosis of Lung Transplantation in Patients with Acute Exacerbations of Interstitial Lung Disease: A Meta-Analysis Based on Cohort Studies.

PURPOSE: This meta-analysis aimed to examine the prognosis of patients with acute exacerbation of interstitial lung disease (AE-ILD) treated with lung transplantation compared to those with stable interstitial lung disease (ILD). METHODS: We conducted a detailed search in PubMed, Embase, Web of Science, and the Cochrane Library, with the primary outcomes being overall survival (OS), acute cellular rejection (ACR), primary graft dysfunction (PGD), and length of stay (LOS). RESULTS: Five cohort studies were included in this meta-analysis, with 183 patients enrolled in the AE-ILD group and 337 patients in the stable-ILD group. The results showed that in regard to perioperative outcomes, the AE-ILD group did not differ from the stable-ILD group in the incidence of ACR (relative risks [RR] = 0.34, p = 0.44) and the incidence of PGD Ⅲ (RR = 0.53, p = 0.43), but had a longer LOS (mean difference = 9.15, p = 0.02). Regarding prognosis, the two also did not differ in 90-day OS (RR = 0.97, p = 0.59), 1-year OS (RR = 1.05, p = 0.66), and 3-year OS (RR = 0.91, p = 0.76). CONCLUSION: Our study concluded that the efficacy of lung transplantation in patients with AE-ILD is not inferior to that of patients with stable ILD. Lung transplantation is one of the potential treatments for patients with AE-ILD.

Living-donor lobar lung transplantation for pulmonary Langerhans cell histiocytosis complicated by extensive thrombi in central pulmonary arteries.

BACKGROUND: Pulmonary Langerhans cell histiocytosis (PLCH) is a rare disorder characterized by the proliferation of Langerhans cells along the small airways, which causes nodular and cystic changes in the lung parenchyma. Lung transplantation can be a life-saving option for patients with severe respiratory failure or pulmonary hypertension. Herein, we present a case of successful lung transplantation in a patient with PLCH who developed unusually large thrombi in the central pulmonary artery. CASE PRESENTATION: A 47-year-old woman with 16-year history of PLCH with rapidly developing respiratory failure was admitted to our hospital for the evaluation of a lung transplant. Enhanced computed tomography revealed large thrombi in dilated central pulmonary arteries. Right heart catheterization revealed severe pulmonary hypertension, with a mean pulmonary artery pressure of 48 mmHg. The thrombi shrank markedly after 3 months of anticoagulation therapy. However, the respiratory status of the patient did not improve. We performed bilateral living-donor lobar lung transplantation with thrombectomy under extracorporeal membrane oxygenation for the remaining thrombi in the main pulmonary arteries. The dilated main pulmonary arteries of the recipient required direct plication for size mismatch. The patient survived in good condition for more than 2 years with no recurrence of thrombosis. CONCLUSION: Preoperative anticoagulation therapy for massive thrombi in the pulmonary arteries was effective and led to safe lung transplantation.

Remdesivir and molnupiravir had comparable efficacy in lung transplant recipients with mild-to-moderate COVID-19: a single center experience.

Introduction: Remdesivir (REM) and molnupiravir (MOL) are commonly used to treat lung transplant recipients (LTRs) with COVID-19; however, the clinical efficacy of these medications is yet to be compared. In this retrospective cohort study, we compared the clinical outcomes between LTRs with mild-to-moderate COVID-19 treated with REM and those treated with MOL. Methods and Results: Between March 2020 and August 2022, 195 LTRs developed COVID-19 at our center. After excluding 82 who presented with severe disease requiring hospitalization, the remaining 113 were included in the analysis: 54 did not receive antiviral treatment, 30 were treated with REM, and 29 were treated with MOL. Adjusted multivariable logistic regression analysis showed similar rates of hospitalization (adjusted odds ratio (aOR) 1.169, [95% confidence interval (95% CI) 0.105-12.997, p = 0.899], ICU admission (aOR 0.822, 95% CI 0.042-16.220, p = 0.898), mechanical ventilation (aOR 0.903, 95% CI 0.015-55.124, p = 0.961), and COVID-19-related mortality (aOR 0.822, 95% CI 0.042-16.220, p = 0.898) between LTRs treated with REM and those treated with MOL for mild-to-moderate COVID-19, irrespective of SARS-CoV-2 strain. Conclusion: MOL may be a suitable alternative to REM to treat LTRs with mild-to-moderate COVID-19, and the choice of antiviral therapy can be driven by practical considerations such as route of administration and drug availability.

Innate and adaptive effector immune drivers of cytomegalovirus disease in lung transplantation: a double-edged sword.

Up to 90% of the global population has been infected with cytomegalovirus (CMV), a herpesvirus that remains latent for the lifetime of the host and drives immune dysregulation. CMV is a critical risk factor for poor outcomes after solid organ transplant, though lung transplant recipients (LTR) carry the highest risk of CMV infection, and CMV-associated comorbidities compared to recipients of other solid organ transplants. Despite potent antivirals, CMV remains a significant driver of chronic lung allograft dysfunction (CLAD), re-transplantation, and death. Moreover, the extended utilization of CMV antiviral prophylaxis is not without adverse effects, often necessitating treatment discontinuation. Thus, there is a critical need to understand the immune response to CMV after lung transplantation. This review identifies key elements of each arm of the CMV immune response and highlights implications for lung allograft tolerance and injury. Specific attention is paid to cellular subsets of adaptive and innate immune cells that are important in the lung during CMV infection and reactivation. The concept of heterologous immune responses is reviewed in depth, including how they form and how they may drive tissue- and allograft-specific immunity. Other important objectives of this review are to detail the emerging role of NK cells in CMV-related outcomes, in addition to discussing perturbations in CMV immune function stemming from pre-existing lung disease. Finally, this review identifies potential mechanisms whereby CMV-directed treatments may alter the cellular immune response within the allograft.

Intensive care unit-acquired weakness - preventive, and therapeutic aspects; future directions and special focus on lung transplantation.

In this editorial, comments are made on an interesting article in the recent issue of the World Journal of Clinical Cases by Wang and Long. The authors describe the use of neural network model to identify risk factors for the development of intensive care unit (ICU)-acquired weakness. This condition has now become common with an increasing number of patients treated in ICUs and continues to be a source of morbidity and mortality. Despite identification of certain risk factors and corrective measures thereof, lacunae still exist in our understanding of this clinical entity. Numerous possible pathogenetic mechanisms at a molecular level have been described and these continue to be increasing. The amount of retrievable data for analysis from the ICU patients for study can be huge and enormous. Machine learning techniques to identify patterns in vast amounts of data are well known and may well provide pointers to bridge the knowledge gap in this condition. This editorial discusses the current knowledge of the condition including pathogenesis, diagnosis, risk factors, preventive measures, and therapy. Furthermore, it looks specifically at ICU acquired weakness in recipients of lung transplantation, because - unlike other solid organ transplants- muscular strength plays a vital role in the preservation and survival of the transplanted lung. Lungs differ from other solid organ transplants in that the proper function of the allograft is dependent on muscle function. Muscular weakness especially diaphragmatic weakness may lead to prolonged ventilation which has deleterious effects on the transplanted lung - ranging from ventilator associated pneumonia to bronchial anastomotic complications due to prolonged positive pressure on the anastomosis.

Augmented humoral response to third and fourth dose of SARS-CoV-2 mRNA vaccines in lung transplant recipients.

BACKGROUND: Since lung transplant recipients (LTRs) exhibit low immunogenicity after two doses of SARS-CoV-2 mRNA vaccines, optimal vaccine strategies for SARS-CoV-2 are required in LTRs. This study aimed to investigate the efficacy and safety of the third and fourth doses of the SARS-CoV-2 mRNA vaccines in LTRs. METHODS: We conducted a single-center study of 73 LTRs and 23 healthy controls (HCs). Participants received two-to-four doses of SARS-CoV-2 mRNA vaccines. The LTRs were divided into three groups based on the number of vaccine dose. IgG titers against SARS-CoV-2 spike protein were measured, and adverse events were assessed. Factors associated with humoral response were analyzed using univariate and multivariate analyses. RESULTS: The Dose 4 group (n = 27) had a higher humoral response rate (P = 0.018) and higher levels of anti-SARS-CoV-2 IgG antibody (P = 0.04) than the Dose 2 group (n = 14). The Dose 3 group (n = 32) had lower humoral response rates (P = 0.005) and levels of anti-SARS-CoV-2 IgG antibody (P = 0.0005) than the HCs (n = 23) even after the same dose. Systemic adverse events were milder in the LTRs than in the HCs (P < 0.05). Increased number of vaccine dose was identified as a predictor of positive humoral response (P = 0.021). CONCLUSION: Booster doses of SARS-CoV-2 mRNA vaccines may enhance humoral response with mild adverse events in LTRs. Repeated vaccination might be warranted for LTRs to prevent SARS-CoV-2 infection.

Impact of Pre-Transplant Left Ventricular Diastolic Pressure on Primary Graft Dysfunction after Lung Transplantation: A Narrative Review.

Lung transplantation (LT) constitutes the last therapeutic option for selected patients with end-stage respiratory disease. Primary graft dysfunction (PGD) is a form of severe lung injury, occurring in the first 72 h following LT and constitutes the most common cause of early death after LT. The presence of pulmonary hypertension (PH) has been reported to favor PGD development, with a negative impact on patients' outcomes while complicating medical management. Although several studies have suggested a potential association between pre-LT left ventricular diastolic dysfunction (LVDD) and PGD occurrence, the underlying mechanisms of such an association remain elusive. Importantly, the heterogeneity of the study protocols and the various inclusion criteria used to define the diastolic dysfunction in those patients prevents solid conclusions from being drawn. In this review, we aim at summarizing PGD mechanisms, risk factors, and diagnostic criteria, with a further focus on the interplay between LVDD and PGD development. Finally, we explore the predictive value of several diastolic dysfunction diagnostic parameters to predict PGD occurrence and severity.

Impact of Dual Thoracic Recovery from Circulatory Death Donors on Heart and Lung Transplant Outcomes.

OBJECTIVES: Concomitant heart and lung recovery can result in increased operative complexity, ischemic time, and competition for resources and anatomic territory. Dual thoracic recovery from circulatory death donors (DCD) may have additional risks that are not fully understood. We investigated the effects of dual heart and lung recovery from DCD donors on thoracic transplant outcomes. METHODS: Using the United Network for Organ Sharing database, we categorized all adult thoracic DCD transplants 2019-2023 by whether the donor heart, lung, or both (dual donors) were recovered. Heart and lung transplant outcomes were compared between dual recovery donors and heart-only or lung-only donors, respectively, using multivariable analyses. RESULTS: Of the 2,513 donors included, 42.9% were heart-only,45.0% were lung-only, and 12.0% were dual donors. Recipients of dual versus heart-only donors had similar likelihood of post-transplant dialysis (18.9% vs. 18.3%, p=0.84), likelihood of stroke (2.9% vs. 4.7%, p=0.34), and 2-year risk of mortality (aHR 1.15 [95% CI: 0.90-1.47], p=0.26), but lower likelihood of acute rejection (10.2% vs. 16.1%, p=0.04). Recipients of dual and lung-only donors had similar likelihood of pre-discharge acute rejection (7.6% vs. 8.5%, p=0.70), intubation at 72 hours (38.9% vs. 45.1%, p=0.13), and ECMO at 72 hours (13.1% vs. 18.1%, p=0.11), as well as 2-year risk of mortality (aHR 1.16 [95% CI: 0.74-1.82], p=0.52). CONCLUSIONS: Recovering both the heart and lungs from a DCD donor does not negatively impact transplant outcomes. Outcomes in this population should continue to be investigated as more data and longer-term follow up become available.

xTrends in racial and ethnic disparities in pediatric lung transplantation in the United States.

BACKGROUND: Racial and ethnic disparities in pediatric lung transplantation (LTx) related to the shifting cystic fibrosis (CF) population receiving highly effective modulator therapy (HEMT) has not been well investigated. METHODS: The UNOS Registry was queried for patients age 1-25 years undergoing bilateral LTx between 1 January 2012 and 31 December 2021. Race and ethnicity were classified as non-Hispanic White, non-Hispanic Black, Hispanic, or none of the above. The primary outcome was posttransplant mortality. Trends in the association between race/ethnicity and mortality were examined using transplant year as a continuous variable and stratifying year based on introduction of HEMT (triple combination therapy) in November 2019. RESULTS: In the study sample (N = 941), 7% of patients were non-Hispanic Black, 15% were Hispanic, and 2% were some other racial or ethnic group. One hundred (11%) received LTx after approval of triple combination therapy, and 407 (43%) died during follow-up. We identified a statistically significant disparity in mortality hazard (hazard ratio: 1.91; 95% confidence interval: 1.31, 2.80) in non-Hispanic Black compared to non-Hispanic White patients in the pre-triple combination therapy era. CONCLUSIONS: We found higher mortality hazard among non-Hispanic Black compared to non-Hispanic White children undergoing LTx in the United States. Further monitoring of LTx outcomes to identify and address disparities is needed in the current era of triple combination therapy for CF.

Recurrent Treatment of Refractory Acute Cellular Rejection with Alemtuzumab after Lung Transplantation.

We present an exceptional case of a lung transplant recipient successfully treated by multiple courses of alemtuzumab for refractory acute cellular rejection. The patient experienced multiple episodes of acute cellular rejection following the transplantation procedure. Alemtuzumab was initiated as third-line rejection treatment and was repeated six times. Each treatment course resulted in complete recovery of the pulmonary function and depletion of T- and B-lymphocytes and NK cells. The onset of rejection was consistently preceded by the recovery of NK cells, while T- and B-lymphocytes remained depleted. This suggests a rejection process mediated by NK cells. This case contributes to recent research findings suggesting that NK cells play a significant role in acute cellular rejection in lung transplant recipients and stresses the importance to further investigate the role of NK cells in rejection. Furthermore, it demonstrates that acute cellular rejection following lung transplantation can be repeatedly managed by treatment with alemtuzumab. DATA AVAILABILITY STATEMENT: The authors confirm that the data supporting the findings of this study are available within the article.

Therapeutic Use of Carbon Monoxide in Ex-Vivo Lung Perfusion in Donor With Prolonged Cold Ischemia.

INTRODUCTION: Carbon monoxide (CO) has been shown to exert protective effects in multiple organs following ischemic injury, including the lung. The purpose of this study was to examine the effects of CO administration during ex vivo lung perfusion (EVLP) on lung grafts exposed to prolonged cold ischemia. METHODS: Ten porcine lungs were subjected to 18 h of cold ischemia followed by 6 h of EVLP. Lungs were randomized to EVLP alone (control, n = 5) or delivery of 500 ppm of CO during the 1st hour of EVLP (treatment, n = 5). Following EVLP, the left lungs were transplanted and reperfused for 4 h. RESULTS: At the end of EVLP, pulmonary vascular resistance (P = 0.007) and wet to dry lung weight ratios (P = 0.027) were significantly reduced in CO treated lungs. Posttransplant, lung graft PaO2/FiO2 (P = 0.032) and compliance (P = 0.024) were significantly higher and peak airway pressure (P = 0.032) and wet to dry ratios (P = 0.003) were significantly lower in CO treated lungs. Interleukin-6 was significantly reduced in plasma during reperfusion in the CO treated group (P = 0.040). CONCLUSIONS: In this preclinical porcine model, CO application during EVLP resulted in better graft performance and outcomes after reperfusion.

Risk factors for mid- and long-term mortality in lung transplant recipients aged 70 years and older.

OBJECTIVES: With increased lung transplantation in those aged 70 and older, limited literature addresses risk factors affecting their survival. Our study aims to identify independent factors impacting mid- and long-term mortality in this elderly population. METHODS: This study analyzed lung transplant patients over 70 from May 2005 to December 2022 using United Network for Organ Sharing data. The 3- or 5-year cohort excluded multi-organ, secondary transplantation and loss to follow-up. Univariable Cox analysis was conducted to assess recipient, donor and transplant factors. Factors with a significance level of P < 0.2 were subsequently included in a multivariable Cox model to identify correlations with 3- and 5-year mortality in patients aged over 70. RESULTS: Multivariable analysis has identified key factors affecting 3- and 5-year mortality in elderly lung transplant patients over 70. Common notable factors include recipient total bilirubin, intensive care unit status at the time of transplantation, donor diabetes, Cytomegalovirus (CMV) mismatch and single lung transplantation. Additionally, Hispanic/Latino patients and ischaemia time of the transplant significantly impact the 3-year mortality, while recipient age, diabetes, nitric oxide use before transplantation and creatinine were identified as unique independent risk factors affecting the 5-year morality. CONCLUSIONS: The study identified several independent risk factors that impact the mid- and long-term survival of lung transplantation for individuals over 70 years. These findings can contribute to the optimization of lung transplant treatment strategies and perioperative management in elderly patients, thereby enhancing the survival rate of this age group.

Outcomes of Concomitant Cardiac Surgical Procedures Performed During Pediatric Lung Transplantation in the United States.

Data on concomitant cardiac surgery (CCS) performed during pediatric lung transplantation (LTx) is limited. Therefore, we conducted a multi-institutional analysis to identify the incidence and outcomes of CCS in pediatric (< 18 years) LTx recipients by merging data (2004-2023) from the United Network for Organ Sharing (UNOS) and Pediatric Health Information System (PHIS) databases. Of the total of 596 pediatric LTx recipients, 87 (15%) underwent CCS. The majority of these cardiac surgeries were atrial septal defect (ASD) closure (90%) followed by aortic arch/descending aortic repair (3%), atrial repair (3%), ventricular septal defect closure (2%), patent ductus arteriosus ligation (2%), and tricuspid valve repair (2%). The median age at LTx was 3 years (IQR: 0-12). Pulmonary hypertension (PHT) was the predominant indication for LTx (54%). Survival to discharge was 94% and 5-years survival was 64%. Our findings indicate CCS in children undergoing LTx has acceptable outcomes.

Bidirectional transfer of human cytomegalovirus strains in donor and recipient seropositive lung transplant patients.

Donor and recipient human cytomegalovirus (HCMV) seropositive (D+R+) lung transplant recipients (LTRs) often harbor multiple strains of HCMV, likely due to transmitted donor (D) strains and reactivated recipient (R) strains. To date, the extent and timely occurrence of each likely source in shaping the post-transplantation (post-Tx) strain population is unknown. Here, we deciphered the D and R origin of the post-Tx HCMV strain composition in blood, bronchoalveolar lavage (BAL), and CD45+ BAL cell subsets. We investigated either D and/or R formalin-fixed paraffin-embedded blocks or fresh D lung tissue from four D+R+ LTRs obtained before transplantation. HCMV strains were characterized by short amplicon deep sequencing. In two LTRs, we show that the transplanted lung is reseeded by R strains within the first 6 months after transplantation, likely by infiltrating CD14+ CD163+/- alveolar macrophages. In three LTRs, we demonstrate both rapid D-strain dissemination and persistence in the transplanted lung for >1 year post-Tx. Broad inter-host diversity contrasts with intra-host genotype sequence stability upon transmission, during follow-up and across compartments. In D+R+ LTRs, HCMV strains of both, D and R origin can emerge first and dominate long-term in subsequent episodes of infection, indicating replication of both sources despite pre-existing immunity.