Search

Background: Donor hearts and lungs are more susceptible to the inflammatory physiologic changes that occur after brain death. Prior investigations have shown that protocolized management of potential organ donors can rehabilitate donor organs that are initially deemed unacceptable. In this review we discuss advances in donor management models with particular attention to the specialized donor care facility model. In addition we review specific strategies to optimize donor thoracic organs and improve organ yield in thoracic transplantation., Methods: We performed a literature review by searching the PubMed database for medical subject heading terms associated with organ donor management models. We also communicated with our local organ procurement organization to gather published and unpublished information first-hand., Results: The specialized donor care facility model has been shown to improve the efficiency of organ donor management and procurement while reducing costs and minimizing travel and its associated risks. Lung protective ventilation, recruitment of atelectatic lung, and hormone therapy (eg, glucocorticoids and triiodothyronine/thyroxine) are associated with improved lung utilization rates. Stroke volume-based resuscitation is associated with improved heart utilization rates, whereas studies evaluating hormone therapy (eg, glucocorticoids and triiodothyronine/thyroxine) have shown variable results., Conclusions: Lack of high-quality prospective evidence results in conflicting practices across organ procurement organizations, and best practices remain controversial. Future studies should focus on prospective, randomized investigations to evaluate donor management strategies. The specialized donor care facility model fosters a collaborative environment that encourages academic inquiry and is an ideal setting for these investigations., (Copyright © 2022 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Purpose of Review: Transplantation continues to be the only treatment option for end-stage organ failure when other interventions have failed. Although short-term outcomes have improved due to advances in perioperative care, long-term outcomes continue to be adversely affected by chronic rejection. Little is known about the role microbiota play in modulating alloimmune responses and potentially contributing to graft failure. Initial data have identified a correlation between specific changes of the recipient and/or donor microbiota and transplant outcomes. In this review, we will focus on recent findings concerning the complex interplay between microbiota and the innate immune system after heart and lung transplantation., Recent Findings: Gut microbiome derangements in heart failure promote an inflammatory state and have lasting effects on the innate immune system, with an observed association between increased levels of microbiota-dependent metabolites and acute rejection after cardiac transplantation. The lung allograft microbiome interacts with components of the innate immune system, such as toll-like receptor signalling pathways, NKG2C+ natural killer cells and the NLRP3 inflammasome, to alter posttransplant outcomes, which may result in the development of chronic rejection., Summary: The innate immune system is influenced by alterations in the microbiome before and after heart and lung transplantation, thereby offering potential therapeutic targets for prolonging allograft survival., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Primary graft dysfunction (PGD) and acute cellular rejection (ACR) are important causes of early morbidity and mortality following lung and heart transplantation. While many studies have elucidated donor-related risk factors of PGD and ACR, these complications often occur even with "ideal" donors. Therefore, we investigated potential associations of PGD and ACR between bilateral lung and heart transplant recipients from the same multiorgan donor, respectively., Methods: Between 2011 and 2017, 100 donors contributed 100 bilateral lung transplants and 100 heart transplants performed. Logistic regression analysis for PGD and Cox proportional hazards regression analysis for ACR were used to estimate the relationship of heart and lung transplants., Results: The incidence of PGD was 33% among lung and 17% among heart transplant recipients. Similarly, the incidence of ACR grade ≥ A2 for lung recipients was 38% (30/80), and the incidence of ACR grade ≥ 2R for heart recipients was 19% (15/80). There was no association between the development of PGD and ACR in lung and heart transplant recipients from the same donor, respectively., Conclusions: These findings suggest that inherent donor factors are not critical to the development of PGD and ACR after lung and heart transplantation., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Two-photon intravital microscopy has substantially broadened our understanding of tissue- and organ-specific differences in the regulation of inflammatory responses. However, little is known about the dynamic regulation of leukocyte recruitment into inflamed heart tissue, largely due to technical difficulties inherent in imaging moving tissue. Here, we report a method for imaging beating murine hearts using intravital 2-photon microscopy. Using this method, we visualized neutrophil trafficking at baseline and during inflammation. Ischemia reperfusion injury induced by transplantation or transient coronary artery ligation led to recruitment of neutrophils to the heart, their extravasation from coronary veins, and infiltration of the myocardium where they formed large clusters. Grafting hearts containing mutant ICAM-1, a ligand important for neutrophil recruitment, reduced the crawling velocities of neutrophils within vessels, and markedly inhibited their extravasation. Similar impairment was seen with the inhibition of Mac-1, a receptor for ICAM-1. Blockade of LFA-1, another ICAM-1 receptor, prevented neutrophil adherence to endothelium and extravasation in heart grafts. As inflammatory responses in the heart are of great relevance to public health, this imaging approach holds promise for studying cardiac-specific mechanisms of leukocyte recruitment and identifying novel therapeutic targets for treating heart disease. [ABSTRACT FROM AUTHOR]

With advancements in basic science and clinical medicine, lung transplantation (LT) has evolved rapidly over the last three decades. However, it is unclear if significant regional variations exist in long-term outcomes after LT. To investigate potential differences, we performed a retrospective, comparative cohort analysis of adult patients undergoing deceased donor single or double LT in North America (NA) or Europe between January 2006 and December 2016. Data up to April 2019 were abstracted from the International Society for Heart and Lung Transplantation (ISHLT) Thoracic Organ Registry. We compared overall survival (OS) between North American and European LT centers in a propensity score matched analysis. In 3,115 well-matched pairs, though 30-day survival was similar between groups (NA 96.2% vs Europe 95.4%, p = 0.116), 5-year survival was significantly higher in European patients (NA 60.1% vs Europe 70.3%, p < 0.001). This survival difference persisted in a sensitivity analysis excluding Canadian patients. Prior observations suggest that these disparities are at least partly related to better access to care via universal healthcare models prevalent in Europe. Future studies are warranted to confirm our findings and explore other causal mechanisms. It is likely that potential solutions will require concerted efforts from healthcare providers and policymakers. [ABSTRACT FROM AUTHOR]