Controlled donation after circulatory death lung transplantation: Results of the French protocol including in situ abdominal normothermic regional perfusion and ex vivo lung perfusion

BACKGROUND

The French national protocol for controlled donation after circulatory determination of death (cDCD) includes normothermic regional perfusion (NRP) in case of abdominal organ procurement and additional ex-vivo lung perfusion (EVLP) before considering lung transplantation (LT).

METHODS

We made a retrospective study of a prospective registry that included all donors considered for cDCD LT from the beginning of the program in May 2016 to November 2021.

RESULTS

One hundred grafts from 14 donor hospitals were accepted by 6 LT centers. The median duration of the agonal phase was 20 minutes [2-166]. The median duration from circulatory arrest to pulmonary flush was 62 minutes [20-90]. Ten lung grafts were not retrieved due to prolonged agonal phases (n = 3), failure of NRP insertion (n = 5), or poor in situ evaluation (n = 2). The remaining 90 lung grafts were all evaluated on EVLP, with a conversion rate of 84% and a cDCD transplantation rate of 76%. The median total preservation time was 707 minutes [543-1038]. Seventy-one bilateral LTs and 5 single LTs were performed for chronic obstructive pulmonary disease (n = 29), pulmonary fibrosis (n = 21), cystic fibrosis (n = 15), pulmonary hypertension (n = 8), graft-versus-host disease (n = 2), and adenosquamous carcinoma (n = 1). The rate of PGD3 was 9% (n = 5). The 1-year survival rate was 93.4%.

CONCLUSION

After initial acceptance, cDCD lung grafts led to LT in 76% of cases, with outcomes similar to those already reported in the literature. The relative impacts of NRP and EVLP on the outcome following cDCD LT should be assessed prospectively in the context of comparative studies.

Réponse vaccinale contre la Covid en transplantation pulmonaire

Introduction

La vaccination contre la Covid a été recommandée chez les patients transplantés d’organes solides en début d’année 2021, selon un schéma comprenant 3 doses chez les patients n’ayant pas présenté d’infection par la Covid 19 et selon un schéma comprenant 2 injections chez les patients ayant été infectés par la Covid.

Méthodes

Nous avons étudié la réponse vaccinale après un schéma complet dans une cohorte de patients transplantés pulmonaires et cardiopulmonaires à l’hôpital Marie Lannelongue. Selon les recommandations de l’OMS, l’absence de réponse vaccinale est définie par une sérologie dont le taux est < 30 BAU/ml. Le taux d’Anticorps considéré comme protecteur est un taux > 260 BAU/ml. Les patients dont le taux est compris entre 30 et 260 BAU/ml sont considérés comme faiblement répondeurs. La sérologie a été effectuée entre 1 et 3 mois après la dernière injection.

Résultats

Dans notre cohorte comprenant 373 patients, une sérologie Covid a pu être obtenue chez 75% des patients. Une absence complète de séroconversion a été constatée chez 75% des patients. Une séroconversion avec un taux d’anticorps considéré comme protecteur n’a été obtenu que chez 14% des patients, dont la moitié a présenté une infection par la Covid. Par ailleurs, 11% des patients ont été faiblement répondeurs.

Conclusion

Notre étude mono-centrique suggère une très faible réponse vaccinale chez les patients transplantés pulmonaires et cardiopulmonaires, suggérant la réalisation d’une 4^e dose chez les patients partiellement répondeurs et/ou un traitement par anticorps monoclonaux spécifiques chez les patients non répondeurs.

Radiofrequency ablation versus surgical resection for the treatment of oligometastatic lung disease

PURPOSE

The purpose of this study was to compare efficacy and tolerance between radiofrequency ablation (RFA) and surgery for the treatment of oligometastatic lung disease.

MATERIALS AND METHODS

This retrospective study reviewed patients treated in two institutions for up to 5 pulmonary metastases with a maximal diameter of 4cm and without associated pleural involvement or thoracic lymphadenopathy. Patient demographics, tumor characteristics, treatment outcome, and length of hospital stay were compared between the two groups. Efficacy endpoints were overall survival (OS), progression-free survival (PFS) and pulmonary or local tumor progression rates.

RESULTS

Among 204 patients identified, 78 patients (42 men, 36 women; mean age, 53.3±14.9 [SD]; age range: 15-81 years) were treated surgically, while 126 patients (59 men, 67 women; mean age, 62.2±10.8 [SD]; age range: 33-80 years) were treated by RFA. In the RFA cohort, patients were significantly older (P<0.0001), with more extra-thoracic localisation (P=0.015) and bilateral tumour burden (P=0.0014). In comparison between surgery and RFA cohorts, respectively, the 1- and 3-year OS were 94.8 and 67.2% vs. 94 and 72.1% (P=0.46), the 1- and 3-year PFS were 49.4% and 26.1% vs. 38.9% and 14.8% (P=0.12), the pulmonary progression rates were 39.1% and 56% vs. 41.2% and 65.3% (P>0.99), and the local tumour progression rates were 5.4% and 10.6% vs. 4.8% and 18.6% (P=0.07). Tumour size>2cm was associated with a significantly higher local tumor progression in the RFA group (P=0.010). Hospitalisation stay was significantly shorter in the RFA group (median of 3 days; IQR=2 days; range: 2-12 days) than in the surgery group (median of 9 days; IQR=2 days; range: 6-21 days) (P<0.01).

CONCLUSION

RFA should be considered a minimally-invasive alternative with similar OS and PFS to surgery in the treatment of solitary or multiple lung metastases measuring less than 4cm in diameter without associated pleural involvement or thoracic lymphadenopathy.

Blood CD9+ B cell, a biomarker of bronchiolitis obliterans syndrome after lung transplantation

Bronchiolitis obliterans syndrome is the main limitation for long-term survival after lung transplantation. Some specific B cell populations are associated with long-term graft acceptance. We aimed to monitor the B cell profile during early development of bronchiolitis obliterans syndrome after lung transplantation. The B cell longitudinal profile was analyzed in peripheral blood mononuclear cells from patients with bronchiolitis obliterans syndrome and patients who remained stable over 3 years of follow-up. CD24^hi CD38^hi transitional B cells were increased in stable patients only, and reached a peak 24 months after transplantation, whereas they remained unchanged in patients who developed a bronchiolitis obliterans syndrome. These CD24^hi CD38^hi transitional B cells specifically secrete IL-10 and express CD9. Thus, patients with a total CD9⁺ B cell frequency below 6.6% displayed significantly higher incidence of bronchiolitis obliterans syndrome (AUC = 0.836, PPV = 0.75, NPV = 1). These data are the first to associate IL-10-secreting CD24^hi CD38^hi transitional B cells expressing CD9 with better allograft outcome in lung transplant recipients. CD9-expressing B cells appear as a contributor to a favorable environment essential for the maintenance of long-term stable graft function and as a new predictive biomarker of bronchiolitis obliterans syndrome-free survival.

P2540Sex-specific differences in the clinical presentation, surgical complications, and course of chronic thromboembolic pulmonary hypertension

Background

Women are more susceptible to develop several forms of pulmonary hypertension, but they may have better survival rates than men. Sparse data are available concerning sex-specific differences in chronic thromboembolic pulmonary hypertension (CTEPH).

Purpose and methods

We investigated sex-specific differences in the clinical presentation of CTEPH, functional parameters, exposure to pulmonary endarterectomy (PEA), and survival.

Results

Women constituted half of the study population (N=679 treatment-naïve patients from the European CTEPH registry) and were characterized by a lower prevalence of some cardiovascular risk factors (e.g. prior acute coronary syndrome, smoking habit, chronic obstructive pulmonary disease), but more prevalent obesity, cancer, and thyroid diseases. Median age was 62 (IQR 50–73) years in women and 63 (IQR 53–70) in men. Women underwent PEA less often than men (54% vs 65%; Figure 1, Panel A) and were exposed to fewer additional cardiac procedures, notably coronary artery bypass graft surgery (0.5% vs. 9.5%). The prevalence of specific reasons for not being operated, including the patient's refusal and the proportion of proximal vs. distal lesions, did not differ between sexes. A total of 57 (17.0%) deaths in women and 70 (20.7%) in men were recorded over long-term follow-up. Female sex was positively associated with long-term survival (adjusted Hazard Ratio 0.66; 95% Confidence Interval 0.46–0.94). Short-term mortality was identical in the two groups (Figure 1, Panel B).

Conclusions

Women with CTEPH had a lower prevalence of cardiovascular risk factors and underwent PEA less frequently than men, who, in turn, were more often exposed to additional major cardiac surgery procedures. Women had more favorable long-term survival.

Acknowledgement/Funding

The CTEPH registry is supported by a research grant from Actelion Pharmaceuticals Ltd.

[Massive pulmonary embolism. When medical treatment is not enough]

Emergency bedside veno-arterious ECMO implantation can be the only saving gesture in the suspicion of acute massive pulmonary embolism leading to haemodynamic failure, even before CT-scan imaging. Once the massive pulmonary embolism is confirmed it is possible to undergo surgical or percutaneous pulmonary thrombectomy, when thrombolytic therapy is contraindicated.

Prevention of ischemia-reperfusion lung injury during static cold preservation by supplementation of standard preservation solution with HEMO2life® in pig lung transplantation model

We describe the results of adding a new biological agent HEMO₂life^® to a standard preservation solution for hypothermic static lung preservation aiming to improve early functional parameters after lung transplantation. HEMO₂life^® is a natural oxygen carrier extracted from Arenicola marina with high oxygen affinity developed as an additive to standard organ preservation solutions. Standard preservation solution (Perfadex^®) was compared with Perfadex^® associated with HEMO₂life^® and with sham animals after 24 h of hypothermic preservation followed by lung transplantation. During five hours of lung reperfusion, functional parameters and biomarkers expression in serum and in bronchoalveolar lavage fluid (BALF) were measured. After five hours of reperfusion, HEMO₂life^® group led to significant improvement in functional parameters: reduction of graft vascular resistance (p < .05) and increase in graft oxygenation ratio (p < .05). Several ischemia-reperfusion related biomarkers showed positive trends in the HEMO₂life^® group: expression of HMG B1 in serum tended to be lower in comparison (2.1 ± 0.8 vs. 4.6 ± 1.5) with Perfadex^® group, TNF-α and IL-8 in BALF were significantly higher in the two experimental groups compared to control (p < .05). During cold ischemia, expression of HIF1α and histology remained unchanged and similar to control. Supplementation of the Perfadex^® solution by an innovative oxygen carrier HEMO₂life^® during hypothermic static preservation improves early graft function after prolonged cold ischemia in lung transplantation.

Bronchial Paraganglioma with SDHB Deficiency

Though most paragangliomas arise as sporadic tumors, the recent advantages in the genetic screening revealed that about 30 % of paragangliomas are linked to hereditary mutations, such as those involving SDH genes. A 22-year-old woman carrying a left main bronchus tumor underwent surgery in our institution. Her past medical history included a GIST without KIT or PDGFRA mutation. The histological examination revealed a nested proliferation of medium-sized cells expressing neuroendocrine markers (chromogranin A and synaptophysin). The neoplastic cells failed to express SDHB gene product. These findings led us to the final diagnosis of bronchial paraganglioma in the setting of Carney-Stratakis syndrome. Bronchial paragangliomas are exceedingly rare tumors with polymorphous clinical presentation, and usually benign clinical course. Though most paragangliomas are sporadic, some tumors are associated with specific hereditary disease, especially those occurring in young patients or in combination with other neoplasms.