Long-term outcomes of lung transplantation with ex vivo lung perfusion technique.

Ex vivo lung perfusion (EVLP) has demonstrated encouraging short- and medium-term outcomes with limited data available on its long-term outcomes. This study assesses (1) EVLP long-term outcomes and (2) EVLP era-based sub-analysis in addition to secondary outcomes of recipients with EVLP-treated donor lungs compared with recipients of conventionally preserved donor lungs in unmatched and propensity score-matched cohorts. Double lung transplants performed between 1st January 2012 and 31st December 2021 were included. A total of 57 recipients received EVLP-treated lungs compared to 202 unmatched and 57 matched recipients who were subjected to non-EVLP-treated lungs. The EVLP group had a significantly lower mean PaO2/FiO2 ratio and significantly higher mean BMI than the non-EVLP group in the unmatched and matched cohorts. The proportion of smoking history in the unmatched cohort was significantly higher in the EVLP group, while a similar smoking history was demonstrated in the matched cohorts. No difference was demonstrated in overall freedom from death and retransplantation between the groups in the unmatched and matched cohorts (unmatched: hazard ratio (HR) 1.28, 95% confidence interval (CI) 0.79-2.07, P = 0.32; matched: HR 1.06, 95% CI 0.59-1.89). P = 0.89). In the unmatched cohort, overall freedom from chronic allograft dysfunction (CLAD) was significantly different between the groups (HR 1.64, 95% CI 1.07-2.52, P = 0.02); however, the cumulative CLAD incidence was similar (HR 0.72, 95% CI 0.48-1.1, P = 0.13). In the matched cohort, the overall freedom from CLAD (HR 1.69, 95% CI 0.97-2.95, P = 0.06) and cumulative CLAD incidence (HR 0.91, 95% CI 0.37-2.215, P = 0.83) were similar between the groups. The EVLP era sub-analysis of the unmatched cohort in 2012-2014 had a significantly higher cumulative CLAD incidence in the EVLP group; however, this was not demonstrated in the matched cohort. All secondary outcomes were similar between the groups in the unmatched and matched cohorts. In conclusion, transplantation of marginal donor lungs after EVLP evaluation is non-detrimental compared to conventionally preserved donor lungs in terms of mortality, retransplantation, cumulative CLAD incidence, and secondary outcomes. Although the unmatched EVLP era of 2012-2014 had a significantly higher cumulative CLAD incidence, no such finding was demonstrated in the matched cohort of the same era.

Urgent lung allocation system in the Scandiatransplant countries.

BACKGROUND: Throughout the world, the scarcity of donor organs makes optimal allocation systems necessary. In the Scandiatransplant countries, organs for lung transplantation are allocated nationally. To ensure shorter wait time for critically ill patients, the Scandiatransplant urgent lung allocation system (ScULAS) was introduced in 2009, giving supranational priority to patients considered urgent. There were no pre-defined criteria for listing a patient as urgent, but each center was granted only 3 urgent calls per year. This study aims to explore the characteristics and outcome of patients listed as urgent, assess changes associated with the implementation of ScULAS, and describe how the system was utilized by the member centers. METHODS: All patients listed for lung transplantation at the 5 Scandiatransplant centers 5 years before and after implementation of ScULAS were included. RESULTS: After implementation, 8.3% of all listed patients received urgent status, of whom 81% were transplanted within 4 weeks. Patients listed as urgent were younger, more commonly had suppurative lung disease, and were more often on life support compared with patients without urgent status. For patients listed as urgent, post-transplant graft survival was inferior at 30 and 90 days. Although there were no pre-defined criteria for urgent listing, the system was not utilized at its maximum. CONCLUSIONS: ScULAS rapidly allocated organs to patients considered urgent. These patients were younger and more often had suppurative lung disease. Patients with urgent status had inferior short-term outcome, plausibly due to the higher proportion on life support before transplantation.

Pulmonary hypertension as a risk factor of mortality after lung transplantation.

PURPOSE: Pulmonary hypertension (PH) is recognized as a risk factor in lung transplantation as reflected in the lung allocation score (LAS). We examined the impact of PH on outcome after lung transplantation, with special emphasis on pre- and post-capillary PH. METHODS: Consecutive lung transplant recipients were evaluated according to ISHLT criteria including right heart catheterization in the period from 1992 to October 2014. Post-transplant survival was assessed according to hemodynamic characteristics: post-capillary PH (mean pulmonary arterial pressure [mPAP] ≥ 25 mmHg and pulmonary arterial wedge pressure [PAWP] > 15 mmHg), pre-capillary PH (mPAP ≥ 25 mmHg, PAWP ≤ 15 mmHg) and non-PH (mPAP < 25 mmHg). RESULTS: Of 518 transplant recipients, 58 (11%) had post-capillary PH. Pre-capillary PH was present in 211 (41%) and 249 (48%) non-PH. Post-capillary PH and pre-capillary PH were associated with worse 90-d outcomes after transplantation compared to non-PH (p = 0.043 and 0.003, respectively). The negative effect persisted 1 yr post-transplantation in pre-capillary PH (p = 0.037), but not in post-capillary PH (p = 0.447). Long-term survival was unaffected by hemodynamic classification. CONCLUSION: Post-capillary PH was present in 11% and pre-capillary PH in 41% of the transplant cohort. Post-capillary PH and pre-capillary PH were associated with inferior 90-d survival, but long-term survival was unaffected.

The number of FoxP3+ cells in transbronchial lung allograft biopsies does not predict bronchiolitis obliterans syndrome within the first five years after transplantation.

BACKGROUND: An important limitation to the success of lung transplantation is the development of bronchiolitis obliterans syndrome (BOS). It has been hypothesized that regulatory T lymphocytes (Tregs) are related to the risk of BOS. We aim to evaluate whether the number of forkhead box P3 (FoxP3+) cells/mm(2) in lung allograft biopsies is a predictor of long-term outcome. MATERIALS AND METHODS: A total of 58 consecutive lung transplant patients were included in the study. For 233 routine surveillance biopsy samples, the numbers of FoxP3+ cells/mm(2) were assessed by immunohistochemical staining with antibodies against FoxP3. BOS scores were calculated for the first five yr after transplantation. RESULTS: We determined that acute rejection was related to the time elapsed from transplantation to BOS with hazard ratios of 3.18 (p = 0.02) and 3.73 (p = 0.04) when comparing the levels of acute rejection grade 1 and grade 2/3, respectively, to no rejection. According to a Cox regression analysis, the number of FoxP3+ cells/mm(2) was not predictive of time to BOS. DISCUSSION AND CONCLUSIONS: Our data indicate that the number of FoxP3+ cells in the lung allograft did not correlate with BOS-free survival time. Previous studies have been contradictory and included different time points. Our findings emphasize the importance of including a time factor.