International society for heart and lung transplantation statement on transplant ethics

Examining a 12-year experience within Kazakhstan's national heart transplantation program

Kazakhstan has one of the lowest heart transplantation (HTx) rates globally, but there are no studies evaluating the outcomes of HTx. This study aimed to provide a comprehensive analysis of the national HTx program over a 12-year period (2012-2023). Survival analysis of the national HTx cohort was conducted using life tables, Kaplan‒Meier curves, and Cox regression methods. Time series analysis was applied to analyze historical trends in HTx per million population (pmp) and to make future projections until 2030. The number of patients awaiting HTx in Kazakhstan was evaluated with a regional breakdown. The pmp rates of HTx ranged from 0.06 to 1.08, with no discernible increasing trend. Survival analysis revealed a rapid decrease in the first year after HTx, reaching 77.0% at 379 days, with an overall survival rate of 58.1% at the end of the follow-up period. Among the various factors analyzed, recipient blood levels of creatinine and total bilirubin before surgery, as well as the presence of infection or sepsis and the use of ECMO after surgery, were found to be significant contributors to the survival of HTx patients. There is a need for public health action to improve the HTx programme.

Donor blood cultures and outcomes after lung transplantation: a single-center report

BACKGROUND

Transplanting lungs from donors with positive blood cultures has not been shown to adversely affect survival. There is limited evidence for potential effects on other outcomes, such as hospital course, graft function, and transmission of infection.

METHODS

This retrospective cohort study included adult patients who underwent lung-only transplantation for the first time between March 2010 and December 2022. Outcomes of patients whose donors had positive blood cultures within 72 h of transplant were compared to patients whose donors had negative blood cultures.

RESULTS

Twenty-five (10.8%) of 232 donors had positive blood cultures, including a single, unexpected case with candidemia. The most commonly isolated bacteria were Enterobacter cloacae (n = 5), Klebsiella pneumoniae (n = 5), Acinetobacter baumannii (n = 3), Pseudomonas aeruginosa (n = 3), and Staphylococcus aureus (n = 3). Eleven donors had identical bacteria in their respiratory cultures. All patients who were transplanted from donors with positive blood cultures survived beyond 90 days. Positive donor blood cultures were not associated with longer hospital stay, in-hospital complications, acute cellular rejection, or the achievement of 80% predicted forced expiratory volume in the first second. Probable transmission of donor bacteremia occurred in only two cases (both with S. aureus). These two donors had positive respiratory cultures with the same organism.

CONCLUSION

The study did not find an increased risk of adverse events when transplanting lungs from donors with positive blood cultures. Allograft cultures may be more predictive of the risk of transmitting infections.

Ex vivo lung perfusion in donation after circulatory death: A post hoc analysis of the Normothermic Ex Vivo Lung Perfusion as an Assessment of Extended/Marginal Donors Lungs trial

OBJECTIVE

Donation after circulatory death (DCD) donors offer the ability to expand the lung donor pool and ex vivo lung perfusion (EVLP) further contributes to this ability by allowing for additional evaluation and resuscitation of these extended criteria donors. We sought to determine the outcomes of recipients receiving organs from DCD EVLP donors in a multicenter setting.

METHODS

This was an unplanned post hoc analysis of a multicenter, prospective, nonrandomized trial that took place during 2011 to 2017 with 3 years of follow-up. Patients were placed into 3 groups based off procurement strategy: brain-dead donor (control), brain-dead donor evaluated by EVLP, and DCD donors evaluated by EVLP. The primary outcomes were severe primary graft dysfunction at 72 hours and survival. Secondary outcomes included select perioperative outcomes, and 1-year and 3-years allograft function and quality of life measures.

RESULTS

The DCD EVLP group had significantly higher incidence of severe primary graft dysfunction at 72 hours (P = .03), longer days on mechanical ventilation (P < .001) and in-hospital length of stay (P = .045). Survival at 3 years was 76.5% (95% CI, 69.2%-84.7%) for the control group, 68.3% (95% CI, 58.9%-79.1%) for the brain-dead donor group, and 60.7% (95% CI, 45.1%-81.8%) for the DCD group (P = .36). At 3-year follow-up, presence observed bronchiolitis obliterans syndrome or quality of life metrics did not differ among the groups.

CONCLUSIONS

Although DCD EVLP allografts might not be appropriate to transplant in every candidate recipient, the expansion of their use might afford recipients stagnant on the waitlist a viable therapy.

Severe Acute Kidney Injury Postheart Transplantation: Analysis of Risk Factors

Background

Acute kidney injury (AKI) is a common complication postheart transplantation and is associated with significant morbidity and increased mortality.

Methods

We conducted a single-center, retrospective, observational cohort study of 109 consecutive patients undergoing heart transplantation between September 2019 and September 2021 to determine major risk factors for, and the incidence of, severe postoperative AKI as defined by Kidney Disease Improving Global Outcomes criteria in the first 48-h posttransplantation and the impact that this has on mortality and dialysis dependence.

Results

One hundred nine patients were included in our study, 83 of 109 (78%) patients developed AKI, 42 (39%) developed severe AKI, and 37 (35%) required renal replacement therapy in the first-week posttransplantation. We found preoperative estimated glomerular filtration rate (eGFR), postoperative noradrenaline dose, and the need for postoperative mechanical circulatory support to be independent risk factors for the development of severe AKI. Patients who developed severe AKI had a 19% 12-mo mortality compared with 1% for those without. Of those who survived to hospital discharge, 20% of patients in the severe AKI group required dialysis at time of hospital discharge compared with 3% in those without severe AKI.

Conclusion

Severe AKI is common after heart transplantation. Preoperative kidney function, postoperative vasoplegia with high requirements for vasoactive drugs, and graft dysfunction with the need for mechanical circulatory supports were independently associated with the development of severe AKI in the first-week following heart transplantation. Severe AKI is associated with a significantly increased mortality and dialysis dependence at time of hospital discharge.

Short airway telomeres are associated with primary graft dysfunction and chronic lung allograft dysfunction

Primary graft dysfunction (PGD) is a major risk factor for chronic lung allograft dysfunction (CLAD) following lung transplantation, but the mechanisms linking these pathologies are poorly understood. We hypothesized that the replicative stress induced by PGD would lead to erosion of telomeres, and that this telomere dysfunction could potentiate CLAD. In a longitudinal cohort of 72 lung transplant recipients with >6 years median follow-up time, we assessed tissue telomere length, PGD grade, and freedom from CLAD. Epithelial telomere length and fibrosis-associated gene expression were assessed on endobronchial biopsies taken at 2 to 4 weeks post-transplant by TeloFISH assay and nanoString digital RNA counting. Negative-binomial mixed-effects and Cox-proportional hazards models accounted for TeloFISH staining batch effects and subject characteristics including donor age. Increasing grade of PGD severity was associated with shorter airway epithelial telomere lengths (p = 0.01). Transcriptomic analysis of fibrosis-associated genes showed alteration in fibrotic pathways in airway tissue recovering from PGD, while telomere dysfunction was associated with inflammation and impaired remodeling. Shorter tissue telomere length was in turn associated with increased CLAD risk, with a hazard ratio of 1.89 (95% CI 1.16-3.06) per standard deviation decrease in airway telomere length, after adjusting for subject characteristics. PGD may accelerate telomere dysfunction, potentiating immune responses and dysregulated repair. Epithelial cell telomere dysfunction may represent one of several mechanisms linking PGD to CLAD.

Hemodynamic failure and graft dysfunction after lung transplant: A possible clinical continuum with immediate and long-term consequences

INTRODUCTION

The postoperative hemodynamic management after lung transplant (LUTX) is guided by limited evidence. We aimed to describe and evaluate risk factors and outcomes of postoperative vasoactive support of LUTX recipients.

METHODS

In a single-center retrospective analysis of consecutive adult LUTX, two cohorts were identified: (1) patients needing prolonged vasoactive support (>12 h from ICU admission) (VASO+); (2) or not (VASO-). Postoperative hemodynamic characteristics were thoroughly analyzed. Risk factors and outcomes of VASO+ versus VASO- cohorts were assessed by multivariate logistic regression and propensity score matching.

RESULTS

One hundred and thirty-eight patients were included (86 (62%) VASO+ versus 52 (38%) VASO-). Vasopressors (epinephrine, norepinephrine, dopamine) were used in the first postoperative days (vasoactive inotropic score at 12 h: 6 [4-12]), while inodilators (dobutamine, levosimendan) later. Length of vasoactive support was 3 [2-4] days. Independent predictors of vasoactive use were: LUTX indication different from cystic fibrosis (p = .003), higher Oto score (p = .020), longer cold ischemia time (p = .031), but not preoperative cardiac catheterization. VASO+ patients showed concomitant hemodynamic and graft impairment, with longer mechanical ventilation (p = .010), higher primary graft dysfunction (PGD) grade at 72 h (PGD grade > 0 65% vs. 31%, p = .004, OR 4.2 [1.54-11.2]), longer ICU (p < .001) and hospital stay (p = .013). Levosimendan as a second-line inodilator appeared safe.

CONCLUSIONS

Vasoactive support is frequently necessary after LUTX, especially in recipients of grafts of lesser quality. Postoperative hemodynamic dysfunction requiring vasopressor support and graft dysfunction may represent a clinical continuum with immediate and long-term consequences. Further studies may elucidate if this represents a possible treatable condition.