Lung transplantation for acute respiratory distress syndrome: a retrospective European cohort study.

BACKGROUND: The published experience of lung transplantation in acute respiratory distress syndrome (ARDS) is limited. The aim of this study was to investigate the contemporary results of lung transplantation attempts in ARDS in major European centres. METHODS: We conducted a retrospective multicentre cohort study of all patients listed for lung transplantation between 2011 and 2019. We surveyed 68 centres in 22 European countries. All patients admitted to the waitlist for lung transplantation with a diagnosis of "ARDS/pneumonia" were included. Patients without extracorporeal membrane oxygenation (ECMO) or mechanical ventilation were excluded. Patients were followed until 1 October 2020 or death. Multivariable analysis for 1-year survival after listing and lung transplantation was performed. RESULTS: 55 centres (81%) with a total transplant activity of 12 438 lung transplants during the 9-year period gave feedback. 40 patients with a median age of 35 years were identified. Patients were listed for lung transplantation in 18 different centres in 10 countries. 31 patients underwent lung transplantation (0.25% of all indications) and nine patients died on the waitlist. 90% of transplanted patients were on ECMO in combination with mechanical ventilation before lung transplantation. On multivariable analysis, transplantation during 2015-2019 was independently associated with better 1-year survival after lung transplantation (OR 10.493, 95% CI 1.977-55.705; p=0.006). 16 survivors out of 23 patients with known status (70%) returned to work after lung transplantation. CONCLUSIONS: Lung transplantation in highly selected ARDS patients is feasible and outcome has improved in the modern era. The selection process remains ethically and technically challenging.

The GermAn Laser Lead Extraction RegistrY: GALLERY.

AIMS: The GermAn Laser Lead Extraction RegistrY: GALLERY is a retrospective, national multicentre registry, investigating the safety and efficacy of laser lead extraction procedures in Germany. METHODS AND RESULTS: Twenty-four German centres that are performing laser lead extraction have participated in the registry. All patients, treated with a laser lead extraction procedure between January 2013 and March 2017, were consecutively enrolled. Safety and efficacy of laser lead extraction were investigated. A total number of 2524 consecutive patients with 6117 leads were included into the registry. 5499 leads with a median lead dwell time of 96 (62-141) months were treated. The mean number of treated leads per patient was 2.18 ± 1.02. The clinical procedural success rate was 97.86% and the complete lead removal was observed in 94.85%. Additional extraction tools were used in 6.65% of cases. The rate of procedural failure was 2.14% with lead age ≥10 years being its only predictor. The overall complication rate was 4.32%, including 2.06% major and 2.26% minor complications. Procedure-related mortality was 0.55%. Female sex and the presence of abandoned leads were predictors for procedure-related complications. The all-cause in-hospital mortality was 3.56% with systemic infection being the strongest predictor, followed by age ≥75 years and chronic kidney disease. CONCLUSION: In the GALLERY, a high success- and low procedure-related complication rates have been demonstrated. In multivariate analysis, female sex and the presence of abandoned leads were predictors for procedure-related complications, while the presence of systemic infection, age ≥75 years, and chronic kidney disease were independent predictors for all-cause mortality.

Lost in circulation.

BACKGROUND: Device complications in complex percutaneous coronary interventions are rare but potentially deadly. Surgical removal is often required. However, an evaluation of surgical therapy beyond case reports is practically not existent. METHODS: We prospectively followed all cases of retained guide wires and/or other devices referred to us for surgical removal between 2015 and 2019 and retrospectively searched our database for such cases between 2010 and 2014. RESULTS: From 2015 on, eight cases were referred for surgical removal from six different cardiology departments. In the 5 years before, there was not a single case. Six patients were operated emergently. Patients were 60.5 ± 5.42 years old, overweight (body mass index 30.1 ± 3.77) and except for one case (left ventricular-assist device) showed preserved ejection fraction (EF) (mean EF 57 ± 18.01). The retained devices were mostly located in the right coronary artery (50%), followed by the circumflex artery (37.5%) and diagonal branch (12.5%). The devices were remnants of guide wires (n = 4), balloon catheters (n = 3), and in one case a rotablator. Full sternotomy was performed in six patients and two received a left-sided minithoracotomy (n = 2). The operations were performed on-pump in five (62.5%) and off-pump in three patients. Complete extraction of the foreign bodies was possible in all patients. Two patients died; one in unrelated multiorgan failure and one due to retained-device-related right heart failure. The other patients survived and had uneventful postoperative courses. CONCLUSIONS: Retained foreign bodies from cardiac interventions can be completely removed surgically using individualized approaches. There appears to be a trend toward a rising incidence of such interventional complications.

Low Fibrinogen Is Associated with Increased Bleeding-Related Re-exploration after Cardiac Surgery.

BACKGROUND: Re-exploration after cardiac surgery remains a relatively frequent complication associated with adverse effects on outcome. We aimed to identify risk factors for re-exploration. METHODS: We retrospectively reviewed 2,403 patients having undergone cardiac surgical procedure between January 2013 and December 2014. Re-exploration was required in 114 patients (4.7%). Patients with oral anticoagulation, infective endocarditis, or a clearly identified bleeding source were excluded. Therefore, 42 patients remained for analysis. A matched cohort was selected for age, sex, ejection fraction, creatinine, and procedure out of the non-re-explored patients. RESULTS: Demographic data were similar in both groups, except for a higher prevalence of diabetes (45 vs. 21%; p = 0.036) in the non-re-explored patients. Surgery was elective in two-thirds and preoperative plasma fibrinogen concentration was lower in patients requiring re-exploration (2.8 ± 0.9 vs. 3.6 ± 0.9 g/L; p = 0.002). During the initial operation, re-explored patients received more packed red blood cells (1.5 ± 3 vs. 0 ± 1 units; p < 0.001), Postoperatively, re-explored patients had higher lactate levels (1.7 ± 1.4 vs. 1.3 ± 0.6 mmol/L, p = 0.044), more chest tube drainage (1,245 ± 948 vs. 685 ± 413 mL; p < 0.001), higher hospital mortality (19 vs. 7%; p = 0.19), and longer intensive care unit (ICU) stays (8 ± 8 vs. 4 ± 7 days; p = 0.010). In addition, more fibrinogen was administrated during the initial surgery. Plasma fibrinogen concentration upon arrival at the ICU was lower in patients requiring re-exploration (2 ± 0.6 vs. 2.7 ± 0.7 g; p < 0.001). Multivariable linear regression analysis identified fibrinogen upon arrival at the ICU as an independent predictor of postoperative bleeding. CONCLUSION: Cardiac surgery patients with low perioperative plasma fibrinogen concentration appear to be more susceptible to bleeding and re-exploration. Re-exploration in this group of patients is associated with increased morbidity and mortality.

The Diagnostic Value of ACSL1, ACSL4, and ACSL5 and the Clinical Potential of an ACSL Inhibitor in Non-Small-Cell Lung Cancer.

Abnormal expression of ACSL members 1, 3, 4, 5, and 6 is frequently seen in human cancer; however, their clinical relevance is unclear. In this study, we analyzed the expression of ACSLs and investigated the effects of the ACSL inhibitor Triacsin C (TC) in lung cancer. We found that, compared to normal human bronchial epithelial (NHBE) cells, ACSL1, ACSL4, and ACSL6 were highly expressed, while ACSL3 and ACSL5 were lost in the majority of lung cancer cell lines. ACSL activity was associated with the expression levels of the ACSLs. In primary lung tumors, a higher expression of ACSL1, ACSL4, and ACSL5 was significantly correlated with adenocarcinoma (ADC). Moreover, ACSL5 was significantly reversely related to the proliferation marker Ki67 in low-grade tumors, while ACSL3 was positively associated with Ki67 in high-grade tumors. Combination therapy with TC and Gemcitabine enhanced the growth-inhibitory effect in EGFR wild-type cells, while TC combined with EGFR-TKIs sensitized the EGFR-mutant cells to EGFR-TKI treatment. Taken together, the data suggest that ACSL1 may be a biomarker for lung ADC, and ACSL1, ACSL4, and ACSL5 may be involved in lung cancer differentiation, and TC, in combination with chemotherapy or EGFR-TKIs, may help patients overcome drug resistance.

Uncovering a unique pathogenic mechanism of SARS-CoV-2 omicron variant: selective induction of cellular senescence.

BACKGROUND: SARS-CoV-2 variants are constantly emerging with a variety of changes in the conformation of the spike protein, resulting in alterations of virus entry mechanisms. Solely omicron variants use the endosomal clathrin-mediated entry. Here, we investigate the influence of defined altered spike formations to study their impact on premature cellular senescence. METHODS: In our study, in vitro infections of SARS-CoV-2 variants delta (B.1.617.2) and omicron (B.1.1.529) were analyzed by using human primary small alveolar epithelial cells and human ex vivo lung slices. We confirmed cellular senescence in human lungs of COVID-19 patients. Hence, global gene expression patterns of infected human primary alveolar epithelial cells were identified via mRNA sequencing. RESULTS: Solely omicron variants of SARS-CoV-2 influenced the expression of cell cycle genes, highlighted by an increased p21 expression in human primary lung cells and human ex vivo lungs. Additionally, an upregulated senescence-associated secretory phenotype (SASP) was detected. Transcriptomic data indicate an increased gene expression of p16, and p38 in omicron-infected lung cells. CONCLUSIONS: Significant changes due to different SARS-CoV-2 infections in human primary alveolar epithelial cells with an overall impact on premature aging could be identified. A substantially different cellular response with an upregulation of cell cycle, inflammation- and integrin-associated pathways in omicron infected cells indicates premature cellular senescence.

Hemodynamic markers of pulmonary vasculopathy for prediction of early right heart failure and mortality after heart transplantation.

BACKGROUND: Elevated pulmonary vascular resistance (PVR) is broadly accepted as an imminent risk factor for mortality after heart transplantation (HTx). However, no current HTx recipient risk score includes PVR or other hemodynamic parameters. This study examined the utility of various hemodynamic parameters for risk stratification in a contemporary HTx population. METHODS: Patients from seven German HTx centers undergoing HTx between 2011 and 2015 were included retrospectively. Established risk factors and complete hemodynamic datasets before HTx were analyzed. Outcome measures were overall all-cause mortality, 12-month mortality, and right heart failure (RHF) after HTx. RESULTS: The final analysis included 333 patients (28% female) with a median age of 54 (IQR 46-60) years. The median mean pulmonary artery pressure was 30 (IQR 23-38) mm Hg, transpulmonary gradient 8 (IQR 5-10) mm Hg, and PVR 2.1 (IQR 1.5-2.9) Wood units. Overall mortality was 35.7%, 12-month mortality was 23.7%, and the incidence of early RHF was 22.8%, which was significantly associated with overall mortality (log-rank HR 4.11, 95% CI 2.47-6.84; log-rank p < .0001). Pulmonary arterial elastance (Ea) was associated with overall mortality (HR 1.74, 95% CI 1.25-2.30; p < .001) independent of other non-hemodynamic risk factors. Ea values below a calculated cutoff represented a significantly reduced mortality risk (HR 0.38, 95% CI 0.19-0.76; p < .0001). PVR with the established cutoff of 3.0 WU was not significant. Ea was also significantly associated with 12-month mortality and RHF. CONCLUSIONS: Ea showed a strong impact on post-transplant mortality and RHF and should become part of the routine hemodynamic evaluation in HTx candidates.

Diabetes Is an Independent Risk Factor for Cancer after Heart and/or Lung Transplantation.

Background: De novo cancers are feared complications after heart or lung transplantation. Recent data suggest that diabetes mellitus (DM) might also be a risk factor for cancer. We hypothesized that transplanted diabetic patients are at greater risk of developing cancer compared to non-diabetic ones. Methods: We reviewed 353 patients post-heart and/or -lung transplantation from our center between October 1999 and June 2021. Patients with follow-up <180 days (n = 87) were excluded from the analysis. The remaining 266 patients were divided into patients who had preoperative DM (n = 88) or developed it during follow-up (n = 40) and patients without DM (n = 138). Results: The diabetic cohort showed higher rates of malignancies in all patients (30.33 vs. 15.97%, p = 0.005) and in the matched population (31.9 vs. 16.1%, p < 0.001). There were also significantly more solid tumors (17.9 vs. 9.4%, p = 0.042; matched: 16.6 vs. 9.1%, p = 0.09) The presence of diabetes was associated with a 13% increased risk of cancer when compared to non-diabetic patients. New-onset post-transplant diabetes doubled the likelihood of cancer development. Conclusions: Pre-transplant diabetes mellitus increases the risk of cancer after heart and/or lung transplantation. However, new-onset diabetes after transplantation is associated with a much greater cancer risk. This information is relevant for screening during follow-up.

Mediastinal Rhabdomyosarcoma Feeding Off the Left Anterior Descending Artery.

We report the rare case of a 51-year-old patient with a 15 cm mediastinal rhabdomyosarcoma with blood supply from the left anterior descending artery presenting as a large mass including the pericardium with extensive contact to the epicardium compressing heart and left lung. The tumor was successfully removed through median sternotomy, blunt dissection from the heart and the left lung, resection of the infiltrated pericardium, and ligation of the tumor-feeding vessels using off-pump stabilizers. Histopathological examination revealed a spindle cell rhabdomyosarcoma with R0 resection. The postoperative course was uneventful, and patient is feeling well at 3-month follow-up.

Study design and rationale of the pAtients pResenTing with cOngenital heaRt dIseAse Register (ARTORIA-R).

AIM: Due to improved therapy in childhood, many patients with congenital heart disease reach adulthood and are termed adults with congenital heart disease (ACHD). ACHD often develop heart failure (HF) as a consequence of initial palliative surgery or complex anatomy and subsequently require advanced HF therapy. ACHD are usually excluded from trials evaluating heart failure therapies, and in this context, more data about heart failure trajectories in ACHD are needed to guide the management of ACHD suffering from HF. METHODS AND RESULTS: The pAtients pResenTing with cOngenital heaRt dIseAse Register (ARTORIA-R) will collect data from ACHD evaluated or listed for heart or heart-combined organ transplantation from 16 countries in Europe and the Asia/Pacific region. We plan retrospective collection of data from 1989-2020 and will include patients prospectively. Additional organizations and hospitals in charge of transplantation of ACHD will be asked in the future to contribute data to the register. The primary outcome is the combined endpoint of delisting due to clinical worsening or death on the waiting list. The secondary outcome is delisting due to clinical improvement while on the waiting list. All-cause mortality following transplantation will also be assessed. The data will be entered into an electronic database with access to the investigators participating in the register. All variables of the register reflect key components important for listing of the patients or assessing current HF treatment. CONCLUSION: The ARTORIA-R will provide robust information on current management and outcomes of adults with congenital heart disease suffering from advanced heart failure.

Epstein-Barr virus-associated pneumonia and bronchiolitis obliterans syndrome in a lung transplant recipient.

We report the case of a 25-year-old lung and liver transplant recipient who developed respiratory failure. High levels of Epstein-Barr virus (EBV) genome copies were detectable in respiratory tract specimens, while the search for various other viral, bacterial or fungal pathogens remained empty. Post-transplant lymphoproliferative disease was excluded. Due to the rapid progression of respiratory insufficiency, a re-transplantation of the lung was performed. EBV-encoded small RNAs could be demonstrated by in situ hybridization within pneumocytes and lymphocytes of the explanted lung tissue. The clinical situation improved soon after re-transplantation, and the EBV load detected in the lower respiratory tract decreased significantly.

Clinical characteristics and outcomes of patients with adult congenital heart disease listed for heart and heart‒lung transplantation in the Eurotransplant region.

BACKGROUND: The therapeutic success in patients with congenital heart disease (CHD) leads to a growing number of adults with CHD (adult CHD [ACHD]) who develop end-stage heart failure. We aimed to determine patient characteristics and outcomes of ACHD listed for heart transplantation. METHODS: Using data from all the patients with ACHD in 20 transplant centers in the Eurotransplant region from 1999 to 2015, we analyzed patient characteristics, waiting list, and post-transplantation outcomes. RESULTS: A total of 204 patients with ACHD were listed during the study period. The median age was 38 years, and 62.3% of the patients were listed in high urgency (HU), and 37.7% of the patients were in transplantable (T)-listing status. A total of 23.5% of the patients died or were delisted owing to clinical worsening, and 75% of the patients underwent transplantation. Median waiting time for patients with HU-listing status was 4.18 months and with T-listing status 9.07 months. There was no difference in crude mortality or delisting between patients who were HU status listed and T status listed (p = 0.65). In multivariable regression analysis, markers for respiratory failure (mechanical ventilation, hazard ratio [HR]: 1.41, 95% CI: 1.11-1.81, p = 0.006) and arrhythmias (anti-arrhythmic medication, HR: 1.42, 95% CI: 1.01-2.01, p = 0.044) were associated with a higher risk of death or delisting. In the overall cohort, post-transplantation mortality was 26.8% after 1 year and 33.4% after 5 years. CONCLUSIONS: Listed patients are at high risk of death without differences in the urgency of listing. Respiratory failure requiring invasive ventilation and possibly arrhythmias requiring anti-arrhythmic medication indicate worse outcomes on waiting list.

Current status and evolution of robotic-assisted thoracic surgery in Germany-results from a nationwide survey.

BACKGROUND: Robot-assisted surgery has made a significant entry into surgical practice within Germany, including thoracic surgery. As no published data exists regarding robotic-assisted thoracic surgery (RATS), we conducted a survey to investigate its current status. METHODS: We performed a nationwide survey of all centers active in RATS, using a standardized questionnaire. The annual number of operations, mean duration of surgery, docking time, length of hospital stay(s), conversions, chest tube duration, the RATS program start date, robot system used, operating room capacity, and staplers and instruments used were recorded. RESULTS: Of the 22 centers contacted, 14 responded. In total, 786 RATS interventions were recorded. Most were anatomical lung resections, comprising 372 (bi-) lobectomies and 80 segmentectomies. During the study period, eight bronchoplastic procedures were performed robotically. There were 93 wedge lung resections, 148 thymectomies, 26 sympathectomies, and 59 other RATS procedures, and a single-center series of around 1,000 RATS thymectomies (excluded from statistical analysis). The average incision-suture time of the RATS lobectomy was 245 (range, 80-419) minutes, average residence time seven days. The conversion rate was 6.7% across all interventions, with significant inter-intervention differences. All surveyed centers plan to further expand RATS, with OR capacity being a frequent impediment. Five RATS interventions were performed in Germany in 2013, versus 320 in 2018. CONCLUSIONS: Overall, RATS is becoming more established in everyday clinical practice in Germany. The number of operations, active centers, and trained RATS surgeons has increased steadily since 2013. A German-speaking operation course for entry into RATS already exists. Even extended resections can be carried out safely, and RATS has become standard procedure in some centers.

The clinical impact of donor-specific antibodies in heart transplantation.

Donor-specific antibodies (DSA) are integral to the development of antibody-mediated rejection (AMR). Chronic AMR is associated with high mortality and an increased risk for cardiac allograft vasculopathy (CAV). Anti-donor HLA antibodies are present in 3-11% of patients at the time of heart transplantation (HTx), with de novo DSA (predominantly anti-HLA class II) developing post-transplant in 10-30% of patients. DSA are associated with lower graft and patient survival after HTx, with one study suggesting a three-fold increase in mortality in patients who develop de novo DSA (dnDSA). DSA against anti-HLA class II, notably DQ, are at particularly high risk for graft loss. Although detection of DSA is not a criterion for pathologic diagnosis of AMR, circulating DSA are found in almost all cases of AMR. MFI thresholds of ~5000 for DSA against class I antibodies, 2000 against class II antibodies, or an overall cut-off of 5-6000 for any DSA, have been suggested as being predictive for AMR. There is no firm consensus on pre-transplant strategies to treat HLA antibodies, or for the elimination of antibodies after diagnosis of AMR. Minimizing the risk of dnDSA is rational but data on risk factors in HTx are limited. The effect of different immunosuppressive regimens is largely unexplored in HTx, but studies in kidney transplantation emphasize the importance of adherence and maintaining adequate immunosuppression. One study has suggested a reduced risk for dnDSA with rabbit antithymocyte globulin induction. Management of DSA pre- and post-HTx varies but typically most centers rely on a plasmapheresis or immunoadsorption, with or without rituximab and/or intravenous immunoglobulin. Based on the literature and a multi-center survey, an algorithm for a suggested surveillance and therapeutic strategy is provided.

Donor heart selection and outcomes: An analysis of over 2,000 cases.

BACKGROUND: Decision-making when offered a donor heart for transplantation is complex, and supportive data describing outcomes according to acceptance or non-acceptance choices are sparse. Our aim was to analyze donor heart acceptance decisions and associated outcomes at a single center, and after subsequent acceptance elsewhere. METHODS: This investigation was a retrospective analysis of data obtained from the University of Vienna Medical Center and Eurotransplant centers for the period 2001 to 2015. RESULTS: Our center accepted 31.8% (699 of 2,199) of donor hearts offered. Unlike other centers, the acceptance rate, with or without transplantation, did not increase over time. Of the donor hearts rejected by our center, 38.1% (572 of 1,500) were later accepted elsewhere. Acceptance rates were twice as high for donor hearts initially rejected for non-quality reasons (339 of 601, 56.4%) compared with initial rejection for quality reasons (233 of 899, 25.9%). Three-year patient survival rate was 79% at Vienna; for donor hearts initially rejected by Vienna for non-quality reasons or quality reasons, it was 73% and 63%, respectively (p < 0.001). Outcomes at other centers after transplantation of grafts rejected by Vienna varied according to the reason for rejection, with good 3-year survival rates for rejection due to positive virology (77%), high catecholamines (68%), long ischemic time (71%), or low ejection fraction (68%), but poor survival was observed for hearts rejected for hypernatremia (46%), cardiac arrest (21%), or valve pathology (50%). CONCLUSIONS: A less restrictive policy for accepting donor hearts at our center, particularly regarding rejection for non-quality reasons or for positive virology, high catecholamine levels, longer ischemic time, or low ejection fraction, could expand our donor pool while maintaining good outcomes.

Chronic Perforation of the Aortic Arch by Kirschner Wires.

Perforation of the heart or great vessels by orthopedic wires is a rare complication that mostly results in severe or even lethal organ injury. Therefore, such conditions mostly require immediate surgical removal of the wires. However, in some individual cases, a conservative approach may be preferable. We describe a case of a 70-year-old woman whose aortic arch has been penetrated by two Kirschner wires used for fixation of a right clavicle fracture 13 years ago. Notably, the complication was an incidental finding during computed tomography angiography for clarification of transient nonspecific neurological symptoms.

Donor pretreatment using the aerosolized prostacyclin analogue iloprost optimizes post-ischemic function of non-heart beating donor lungs.

BACKGROUND: Ischemia-reperfusion injury accounts for one-third of early deaths after lung transplantation. To expand the limited donor pool, lung retrieval from non-heart beating donors (NHBD) has been introduced recently. However, because of potentially deleterious effects of warm ischemia on microvascular integrity, use of NHBD lungs is limited by short tolerable time periods before preservation. After intravenous prostanoids are routinely used to ameliorate reperfusion injury, the latest evidence suggests similar efficacy of inhaled prostacyclin. Therefore, the impact of donor pretreatment with the prostacyclin analogue iloprost on postischemic NHBD lung function and preservation quality was evaluated. METHODS: Asystolic pigs (5 per group) were ventilated for 180 minutes of warm ischemia (Group 2). In Group 3, 100 microg iloprost was aerosolized during the final 30 minutes of ventilation with a novel mobile ultrasonic nebulizer. Lungs were then retrogradely preserved with Perfadex and stored for 3 hours. After left lung transplantation and contralateral lung exclusion, hemodynamics, rO2/FiO2, and dynamic compliance were monitored for 6 hours and compared with sham-operated controls (Group 1). Pulmonary edema was determined both stereologically and by wet-to-dry weight ratio (W/D). Statistics comprised analysis of variance with repeated measures and Mann-Whitney test. RESULTS: Flush preservation pressures, dynamic compliance, inspiratory pressures, and W/D were significantly superior in iloprost-treated lungs, and oxygenation and pulmonary hemodynamics were comparable between groups. Stereology revealed a trend toward lower intraalveolar edema formation in iloprost-treated lungs compared with untreated grafts. CONCLUSIONS: Alveolar deposition of Iloprost and NHBD lungs before preservation ameliorates postischemic edema and significantly improves lung compliance. This easily applicable innovation approach, which uses a mobile ultrasonic nebulizer, offers an important strategy for improvement of pulmonary preservation quality and might expand the pool of donor lungs.

Experimental lung transplantation: impact of preservation solution and route of delivery.

BACKGROUND: Optimal preservation of allograft integrity is essential to reduce post-ischemic organ dysfunction after lung transplantation. Retrograde organ preservation leads to homogeneous intrapulmonary distribution and eliminates intravascular thrombi. So far, no comparative studies exist with regard to preservation quality following retrograde preservation with Perfadex and Celsior after extended cold-ischemia intervals. METHODS: In an in vivo pig model, 5 lungs each were preserved for 27 hours using antegrade or retrograde perfusion techniques with Celsior (Ce(ant)/CE(ret)) and Perfadex (PER(ant)/PER(ret)). After left lung transplantation and contralateral lung exclusion, hemodynamics, oxygenation and dynamic compliance were monitored for 6 hours and compared with sham-operated controls. Pulmonary edema was determined stereologically. Statistics consisted of analysis of variance (ANOVA) with repeated measures. RESULTS: Mortality of all Celsior-protected lungs was 100% due to severe reperfusion injury with profound lung edema. In contrast, organ preservation with PER(ant) led to sufficient graft function without mortality. Preservation quality after retrograde administration of Perfadex resulted in optimized oxygenation capacity compared with PER(ant) (p = 0.046). Furthermore, intra-alveolar edema was reduced and generally comparable with sham controls. In general, retrograde preservation led to continuous washout of small blood and fibrin clots from the pulmonary capillary system. CONCLUSIONS: Perfadex solution provided sufficient lung preservation for 27 hours of cold ischemia, and its retrograde application led to significant functional and histologic improvement compared with antegrade perfusion. In contrast, preservation with Celsior solution resulted in lethal post-ischemic outcome, regardless of the route of administration, and therefore must be considered unsuitable for extended lung procurement.

Innovative pulmonary preservation of non-heart-beating donor grafts in experimental lung transplantation.

OBJECTIVE: Lung transplantation is limited by scarcity of donor organs. Lung retrieval from non-heart-beating donors (NHBD) might have the potential to extend the donor pool and has been reported recently. However, no studies in NHBD exist using the novel approach of retrograde preservation with Perfadex solution. METHODS: Asystolic heparinized pigs (n = 5/group) were continuously ventilated for 90, 180 or 300 min of warm ischemia. Lungs were then retrogradely preserved with Perfadex and stored at 4 degrees C in inflation. After 3 h of additional cold ischemia, left lung transplantation was performed. Hemodynamics, pO(2)/F(i)O(2) and dynamic compliance were monitored for 5 h. Intrapulmonary lung water was determined by both global wet-to-dry lung weight ratio (W/D ratio) and standard stereological examination of relative volume fractions of intraalveolar edema. All results were compared to sham-operated controls and to lungs obtained from standard heart-beating donors after retrograde preservation with Perfadex and 27 h of cold ischemia. Statistics comprised ANOVA analysis with repeated measures and Mann-Whitney tests. RESULTS: No mortality was observed. During flush preservation of NHBD lungs, continuous elimination of blood clots via the pulmonary artery was observed. Oxygenation, compliance, intraalveolar edema fraction and W/D ratio were comparable between groups, whereas PVR was significantly lower in sham-controls. CONCLUSIONS: Use of NHBD lungs is feasible and results in similar postischemic outcome when compared to sham-controls and standard preservation procedures even after 5 h of pre-harvest warm ischemia. Especially, the NHBD with high-risk constellations for intravascular coagulation might benefit from retrograde preservation by elimination of thrombi from the pulmonary circulation. This innovative technique might also be considered in situations, where brain-dead organ donors become hemodynamically unstable prior to onset of organ harvest. Further trials with longer warm and cold ischemic periods are initiated to further elucidate this promising approach of donor pool expansion.