Are heart-lung transplant recipients protected from developing bronchiolitis obliterans syndrome?

Which strategy is better for lung transplantation: Cardiopulmonary bypass or extracorporeal membrane oxygenation?

Background: In lung transplantation surgery, extracorporeal life support (ECLS) is essential for safety. Various support methods, including cardiopulmonary bypass (CPB) and off-pump techniques, are used, with extracorporeal membrane oxygenation (ECMO) gaining prominence. However, consensus on the best support strategy is lacking.Purpose: This article reviews risks, benefits, and outcomes of different support strategies in lung transplantation. By consolidating knowledge, it aims to clarify selecting the most appropriate ECLS modality.Research Design: A comprehensive literature review examined CPB, off-pump techniques, and ECMO outcomes in lung transplantation, including surgical results and complications.Study Sample: Studies, including clinical trials and observational research, focused on ECLS in lung transplantation, both retrospective and prospective, providing a broad evidence base.Data Collection and/or Analysis: Selected studies were analyzed for surgical outcomes, complications, and survival rates associated with CPB, off-pump techniques, and ECMO to assess safety and effectiveness.Results: Off-pump techniques are preferred, with ECMO increasingly vital as a bridge to transplant, overshadowing CPB. However, ECMO entails hidden risks and higher costs. While safer than CPB, optimizing ECMO postoperative use and monitoring is crucial for success.Conclusions: Off-pump techniques are standard, but ECMO's role is expanding. Despite advantages, careful ECMO management is crucial due to hidden risks and costs. Future research should focus on refining ECMO use and monitoring to improve outcomes, emphasizing individualized approaches for LT recipients.

Prognosis factors in heart-lung transplantation: 30 years experience in a reference center

INTRODUCTION

Heart-lung transplantation has shown a progressive decrease in the number of procedures. There is a lack of information about this field in Spain. The main goal of this study is to analyze the experience of a national reference hospital.

METHODS

We performed a retrospective study of a historical cohort of heart-lung transplanted patients in a single center, during a 30 years period (from 1990 to 2021). The associations between variables were evaluated using the χ2 test or Fisher's exact test. Survival was analyzed using the Kaplan-Meier method. Differences were evaluated using the log-rank test and multivariate analysis with the Cox method.

RESULTS

A decrease in the number of procedures performed in the last decade was observed [2000-2009: 19 procedures (44.2%); 2010-2021: 15 procedures (34.8%)]. Early postoperative mortality was 23.3%, falling to 13.3% from 2010. In-hospital mortality was 41%, falling to 33% from 2010. Main factors related to higher mortality: previous thoracic surgery, corticosteroid therapy, extracorporeal circulation (ECLS) greater than 200 min, ischemia time greater than 300 min, and tracheal dehiscence (p < 0.005). Overall survival at one, five, and ten years was 58%, 44.7%, and 36.1%, respectively. Factors associated with lower survival rates: previous thoracic surgery, male donor, extracorporeal circulation greater than 200 min, ischemia time greater than 300 min, tracheal dehiscence and weight difference (p < 0.005).

CONCLUSIONS

There has been a progressive decrease in the number of heart-lung transplantations, being more evident in the last decade, but showing an improvement in both mortality and survival.

Double-lung versus heart-lung transplantation for end-stage cardiopulmonary disease: a systematic review and meta-analysis

We compared posttransplant outcomes following double-lung transplantation (DLTx) and heart-lung transplantation (HLTx), based on a search of PubMed, Cochrane Library, and Embase, from inception to March 8, 2022, for studies that report outcomes of these procedures. We then performed a meta-analysis of baseline characteristics and posttransplant outcomes. Subgroup analyses were implemented according to indication, publication year, and center. This study was registered on PROSPERO (number CRD42020223493). Ten studies were included in this meta-analysis, involving 1230 DLTx patients and 1022 HLTx patients. The DLTx group was characterized by older donors (P = 0.04) and a longer allograft ischemia time (P < 0.001) than the HLTx group. The two groups had comparable 1-year, 3-year, 5-year, 10-year survival rates (all P > 0.05), with similar results identified in subgroup analyses. We found no significant differences in 1-year, 5-year, and 10-year chronic lung allograft dysfunction (CLAD)-free survival, length of intensive care unit stay and hospital stay, length of postoperative ventilation, in-hospital mortality, or surgical complications between the groups (all P > 0.05). Thus, DLTx provides similar posttransplant survival to HLTx for end-stage cardiopulmonary disease. These two procedures have a comparable risk of CLAD and other posttransplant outcomes.

Comparison of mechanical cardiopulmonary support strategies during lung transplantation

INTRODUCTION

Lung transplantation outcomes are influenced by the intraoperative mechanical cardiopulmonary support strategy used. This surgery was historically done either on cardiopulmonary bypass (CPB) or off pump. Recently, there has been increased interest in intraoperative support with veno-arterial (VA) or veno-venous (VV) extracorporeal membrane oxygenation (ECMO). However, there is a lack of consensus on the relative risks, benefits and indications for each intraoperative support strategy.

AREAS COVERED

This review includes information from cohort studies, case-control studies, and case series that compare morbidity and/or mortality of two or more intraoperative cardiopulmonary support strategies during lung transplantation.

EXPERT OPINION

The optimal strategy for intraoperative cardiopulmonary support during lung transplantation remains an area of debate. Current data suggest that off pump is associated with better outcomes and could be considered whenever feasible. ECMO is generally associated with preferable outcomes to CPB, but the data supporting this association is not robust. Interestingly, whether CPB is unplanned or prolonged might influence outcomes more than the use of CPB itself. These observations can help guide surgical teams in their approach for intraoperative mechanical support strategy during lung transplantation and should serve as the basis for further investigations.

Combined Heart Lung Transplantation: An Updated Review of the Current Literature

Heart lung transplantation is a viable treatment option for patients with many end-stage heart and lung pathologies. However, given the complex nature of the procedure, it is imperative that patients are selected appropriately, and the clinician is aware of the many unique aspects in management of this population. This review seeks to describe updated organ selection policies, perioperative and postoperative management strategies, monitoring of graft function, and clinical outcomes for patients after combined heart-lung transplantation in the current era.

Quality of Life and Bronchiolitis Obliterans Syndrome in Patients after Lung Transplantation

Background

Lung transplantation has become an established and effective treatment for patients with end-stage pulmonary disease.

Objective

To investigate health-related quality of life in correlation with occurrence and degree of bronchiolitis obliterans syndrome after transplantation.

Methods

In a cross-sectional study design, 119 consecutive lung transplant recipients (63.9% bilateral and 36.1% single lung transplants) responded voluntarily to a set of standardized questionnaires (12-Item Short-Form Health Survey, Center for Epidemiologic Studies-Depression Scale, Coping With Everyday Life, Beck Anxiety Inventory, Zerssen list of complaints) that covered health-related quality of life and psychological well being. Also, we performed pulmonary function studies to clinically grade bronchiolitis obliterans syndrome in all patients.

Results

In this cohort, 41.2% of patients developed bronchiolitis obliterans syndrome at a mean interval of 5.6 years after lung transplantation. Actuarial freedom from bronchiolitis obliterans syndrome was 90.1%±2.3% at 1 year, 79.9%±3.7% at 3 years, and 59.5%±4.8% at 5 years after lung transplantation. Recipients with bronchiolitis obliterans syndrome reported significantly lower well being and quality of life than those without bronchiolitis obliterans syndrome, who scored similar to healthy volunteers. In a subanalysis, body functioning ( P<.001) and related areas of coping ( P<.001) were mostly affected by bronchiolitis obliterans syndrome.

Conclusions

Quality of life was negatively affected by the onset of bronchiolitis obliterans syndrome. However, even patients who develop bronchiolitis obliterans syndrome reported a temporary benefit from lung transplantation. In addition to optimal medical care and efforts in preventing bronchiolitis obliterans syndrome, psychological support of lung recipients seems to be essential, especially when bronchiolitis obliterans syndrome occurs.

Clinical Outcomes of Heart-Lung Transplantation: Review of 10 Single-Center Consecutive Patients

BACKGROUND

Heart-lung transplantation (HLT) has provided hope to patients with end-stage lung disease and irreversible heart dysfunction. We reviewed the clinical outcomes of 10 patients who underwent heart-lung transplantation at Asan Medical Center.

METHODS

Between July 2010 and August 2014, a total of 11 patients underwent HLT at Asan Medical Center. After excluding one patient who underwent concomitant liver transplantation, 10 patients were enrolled in our study. We reviewed the demographics of the donors and the recipients' baseline information, survival rate, cause of death, and postoperative complications. All patients underwent follow-up, with a mean duration of 26.1±16.7 months.

RESULTS

Early death occurred in two patients (20%) due to septic shock. Late death occurred in three patients (38%) due to bronchiolitis obliterans (n=2) and septic shock (n=1), although these patients survived for 22, 28, and 42 months, respectively. The actuarial survival rates at one year, two years, and three years after HLT were 80%, 67%, and 53%, respectively.

CONCLUSION

HLT is a procedure that is rarely performed in Korea, even in medical centers with large heart and lung transplant programs. In order to achieve acceptable clinical outcomes, it is critical to carefully choose the donor and the recipient and to be certain that all aspects of the transplant procedure are planned in advance with the greatest care.

The Role of Infections in BOS

Background: Infectious agents, particularly cytomegalovirus (CMV), have long been considered to be potential triggers for BOS, although the exact magnitude of the role of infections and the mechanisms thereof remain an area of active research. Methods: This chapter will review previous literature and newer results concerning the possible roles of CMV, other herpesviruses, community-acquired respiratory viruses, bacteria (including Pseudomonas, other gram-negative, gram-positive, and atypical organisms), and fungi, including colonization as well as invasive infection. Results: The text reviews and evaluates the body of literature supporting a role for these infectious agents as risk factors for BOS and time to BOS. Changing patterns of infection over time are taken into account, and studies that have shown an association between BOS (or lack thereof) and CMV are reviewed. Strategies for prevention or early treatment of infections are discussed as potential means of preserving allograft function long term. Immunizations, stringent infection-control practices, and antimicrobial treatment including newer therapies will be discussed. Conclusion: In addition to the classic literature that has focused on CMV, an expanding spectrum of infectious organisms has been implicated as possible risk factors for BOS. Increasing knowledge of the impact of long-term antiviral suppression, prophylaxis, and outcomes of early therapy will help guide future recipient management.

Aggressive coronary artery vasculopathy after combined heart-lung transplantation

Combined heart-lung transplantation remains as a treatment option for patients with cardiopulmonary failure. There is speculation that lung grafts protect the heart from developing graft vasculopathy after combined heart-lung transplantation. This protective mechanism is more likely, at best, a delay in the onset of coronary artery vasculopathy. We present our experiences in two cases of an aggressive form of cardiac allograft vasculopathy after combined heart-lung transplantation that resulted in the death of both patients.

Acute rejection and humoral sensitization in lung transplant recipients

Despite the recent introduction of many improved immunosuppressive agents for use in transplantation, acute rejection affects up to 55% of lung transplant recipients within the first year after transplant. Acute lung allograft rejection is defined as perivascular or peribronchiolar mononuclear inflammation. Although histopathologic signs of rejection often resolve with treatment, the frequency and severity of acute rejections represent the most important risk factor for the subsequent development of bronchiolitis obliterans syndrome (BOS), a condition of progressive airflow obstruction that limits survival to only 50% at 5 years after lung transplantation. Recent evidence demonstrates that peribronchiolar mononuclear inflammation (also known as lymphocytic bronchiolitis) or even a single episode of minimal perivascular inflammation significantly increase the risk for BOS. We comprehensively review the clinical presentation, diagnosis, histopathologic features, and mechanisms of acute cellular lung rejection. In addition, we consider emerging evidence that humoral rejection occurs in lung transplantation, characterized by local complement activation or the presence of antibody to donor human leukocyte antigens (HLA). We discuss in detail methods for HLA antibody detection as well as the clinical relevance, the mechanisms, and the pathologic hallmarks of humoral injury. Treatment options for cellular rejection include high-dose methylprednisolone, antithymocyte globulin, or alemtuzumab. Treatment options for humoral rejection include intravenous immunoglobulin, plasmapheresis, or rituximab. A greater mechanistic understanding of cellular and humoral forms of rejection and their role in the pathogenesis of BOS is critical in developing therapies that extend long-term survival after lung transplantation.

Effects of Sinus Surgery on lung Transplantation Outcomes in Cystic Fibrosis

Background

In cystic fibrosis (CF) patients who are candidates for lung transplant, pretransplant sinus surgery has been advocated to avoid bacterial seeding of the transplanted lungs. This study reviews the 17-year experience of pretransplant sinus surgery among CF patients at a major transplant center.

Methods

Retrospective chart review was performed in all CF patients who underwent heart-lung or lung transplantation at Stanford Medical Center between 1988 and 2005. Postoperative culture data from bronchoalveolar lavage (BAL) and sinus aspirates were evaluated, in addition to survival data.

Results

Eighty-seven CF transplant recipients underwent pretransplant sinus surgery; 87% (n = 59/68) of patients showed recolonization of the lung grafts with Pseudomonas on BAL cultures. The median postoperative time to recolonization was 19 days. Bacterial floras cultured from sinuses were similar in type and prevalence as the floras cultured from BAL. When compared with published series of comparable cohorts in which pretransplant sinus surgery was not performed, there was no statistically significant difference in the prevalence of Pseudomonas recolonization. Times to recolonization also were similar. Survival rates in our cohort were similar to national survival rates for CF lung transplant recipients.

Conclusion

Despite pretransplant sinus surgery, recolonization of lung grafts occurs commonly and rapidly with a spectrum of flora that mimics the sinus flora. Survival rates of CF patients who undergo prophylactic sinus surgery are similar to those from centers where prophylactic sinus surgery is not performed routinely. Pretransplant sinus surgery does not appear to prevent lung graft recolonization and is not associated with overall survival benefit.