Heart-lung Transplant Patients Research Articles

(980) Short Term Outcomes of Combined Heart-Lung Transplant Patients from India

(980) Short Term Outcomes of Combined Heart-Lung Transplant Patients from India

Two consecutive major lower limb operations in a heart-lung transplant recipient during COVID pandemic: A case report and literature review

Introduction: Combined heart and lung transplant is a rare procedure performed for patients with congenital heart disease and end stage pulmonary disease. Due to improvement in survival, non-cardiac surgeries are frequently performed in these patients and anaesthetists are involved in their perioperative management. Apart from increasing the physical and mental health risks, COVID-19 pandemic has posed an additional challenge to health care providers in the management of these immunosuppressed patients. Case presentation: We report a case of a 64-year-old female patient with a previous combined heart and lung transplant who underwent two consecutive lower limb surgeries during COVID pandemic.Conclusion: Meticulous preoperative assessment involving multidisciplinary team, knowledge of the pathophysiology of heart–lung transplant patients, choosing appropriate anaesthetic technique is vital in successful management of these patients. Psychological implications of COVID-19 pandemic in immunosuppressed patients should be considered.

Torque Teno Virus Does Not Predict Cytomegalovirus Infection Post-Lung Transplantation

Purpose Torque teno virus (TTV) is a highly prevalent, non-pathogenic DNA virus that has been shown to correlate with immunosuppression post-transplantation. Cytomegalovirus (CMV) is the most common opportunistic infection to occur post-lung transplantation and is associated with morbidity and mortality. We evaluated the association between plasma TTV load and subsequent occurrence of CMV infection in lung transplant recipients at moderate risk for a CMV infection. Methods All adult, first-time lung and heart-lung transplant patients with moderate risk serotype for CMV infection [donor positive (D+) / recipient positive (R+)] transplanted between September 2005 and December 2013 in our program were included in the study. During this period, our program's CMV prophylaxis strategy was to use valganciclovir for 3 months post-transplant. Existing stored blood samples were retrieved and TTV DNA was quantified using real-time polymerase chain reaction (PCR), measured at 3, 4 and 5 months after lung transplantation, as well as at the time of detection in those who developed a CMV infection. Paired t-tests were used for serial data comparisons and Cox regression was performed to determine an association between log TTV PCR levels and CMV infection within 6 months of discontinuing antiviral prophylaxis. Results During the study period 297 patients were transplanted. Of these patients, 89 patients had D+/R+ serostatus, of which blood samples for TTV PCR testing were available for 76 patients. Only 1 patient did not have any detectable TTV PCR post-transplant. Within this cohort, 34/75 patients (45%) developed a CMV infection within 6 months of discontinuing antiviral prophylaxis. Baseline mean log TTV PCR levels one week after discontinuation of CMV prophylaxis was no different between those that went on to develop a CMV infection and those that did not (6.80 ± 1.08 vs 7.08 ± 0.75, p=0.20). For those developing CMV infection, mean log TTV PCR levels were slightly lower at the time of CMV infection compared to baseline levels (6.45 ± 1.36 vs 6.98 ± 0.72, p=0.04). TTV viral load was not associated with time to CMV infection, HR 0.76 (95% CI 0.55 - 1.05, p=0.09). Conclusion TTV PCR levels at the time of discontinuation of CMV prophylaxis in CMV D+/R+ lung transplant recipients were not associated with subsequent CMV infection. TTV's role in predicting future infection requires further study.

Lung transplantation as an intervention for pediatric pulmonary hypertension.

Lung transplantation is a treatment option for selected children with end-stage lung disease and pulmonary vascular disorders. Overall, pulmonary hypertension (PH) is the second most frequent indication for infants and children requiring lung transplants. In pediatric PH patients, timing for listing remains a difficult decision due to patient heterogeneity and varying allocation policies across different countries. Furthermore, perioperative management can be challenging, making interdisciplinary collaboration among surgical, anesthesiology, critical care, and lung transplant teams essential. Because pediatric PH patients typically have preserved cardiac index and exercise tolerance even with advanced disease, they should be referred early even if they do not meet the criteria for listing of primarily adults by International Society for Heart and Lung Transplantation (ISHLT) published in 2015: New York Heart Association (NYHA) functional class III or IV without improvement, cardiac index < 2 L/min/m2 , mean right atrial pressure of >15 mmHg. Bridging strategies with extracorporeal support should be determined at the time of listing in anticipation of possible clinical deterioration. Bilateral lung transplantation using cardiopulmonary bypass to provide hemodynamic stability is nowadays the standard surgical approach in pediatric centers. The immediate post-transplant period is characterized by dramatic changes in the right ventricle (RV) and and left ventricle (LV) anatomy and physiology, which can be life-threatening. Induction, immunosuppression, prophylaxis, and surveillance are not different from patients without PH. Overall, outcomes in pediatric lung and heart-lung transplant patients for PH are not different from those children undergoing transplantation for other indications. In fact, long-term survival is superior in children with idiopathic PH compared to other diseases, providing most recipients with improved quality of life.

Why do lung transplant patients discontinue triazole prophylaxis?

Lung transplant recipients are prone to invasive fungal infections prompting many transplant centers to use prolonged triazole antifungal prophylaxis. From a practical standpoint, it is unclear if lung transplant recipients are able to continue prolonged or lifelong prophylaxis without premature discontinuation from side effects, drug interactions, development of fungal disease, or medication cost. We examined the number of patients that are able to reach a prophylactic endpoint and understand the reasons for early termination. We conducted a retrospective chart review of all lung and heart-lung transplant patients at Mayo Clinic Rochester from May 1, 2002 to December 31, 2017. Type, duration, and reason for discontinuation of triazole prophylaxis were examined. During the study period, 193 patients underwent lung or heart-lung transplantation. Itraconazole, voriconazole, and posaconazole were given to 180, 73, and 60 post-transplant patients, respectively. Providers switched itraconazole to another prophylactic antifungal medication for reasons other than prophylactic completion in 61.8% (126 out of 204) of exposure episodes; this was similar with voriconazole (68.8%, 53 out of 77, P=0.41). Posaconazole was actively discontinued significantly less often (18.3%, 11 out of 60, P<0.05). The most common reasons for discontinuing itraconazole were malabsorption (15.5% of exposure episodes) and concern for breakthrough fungal infection (10.2%). In comparison, the most common reason for voriconazole discontinuation was side effect or intolerance (54.5% of VR exposure episodes vs 9.8% of IT exposure episodes, P<0.05). Itraconazole and posaconazole appeared to have fewer side effects prompting discontinuation than voriconazole, but itraconazole was discontinued more often because of malabsorption and clinical suspicion of fungal infections.

Survival for Combined Heart-Lung Transplant (HLT) Recipients over the Past 30 Years

Purpose Comparison outcomes in HLT recipients have not been well described over time. We sought to investigate the impact of era in HLT survival (ERA1: 1987-1998 & ERA2: 1999-2018). Methods We conducted a retrospective, cohort analysis of the UNOS Registry of all HLT patients between 1987-2018, comparing mortality rates between ERA1 & ERA2. Exclusions include age proportional hazard regression analysis (adjusted for age, sex, diabetes , race, ischemic time , dialysis, life support, waiting time & HLA mismatch) was performed. Results 1132 HLT pts were identified from 1987-2018, of which 584 and 548 underwent HLT during ERA1 & ERA2, respectively. ERA2 recipients were more likely to be older (36.9 ± 15.8y vs 32.3 ± 14.1y, p graft failure increased (11.3 vs 6.9%) (p=0.001). Conclusion Overall, HLT survival improved in the more recent era despite higher risk characteristics. Improvement in survival is likely multifactorial with improved patient selection, surgical technique and post-HLT immunosuppressive management. Further study is warranted to better understand and improve outcomes.

Everolimus Use for Intolerance or Failure of Baseline Immunosuppression in Adult Heart and Lung Transplantation.

BackgroundEverolimus can be utilized after heart or lung transplantation to reduce calcineurin inhibitor associated nephrotoxicity, due to cell cycle inhibitor adverse effects, and as adjunct therapy for rejection, cardiac allograft vasculopathy, and bronchiolitis obliterans syndrome.Material/MethodsA single-center, retrospective cohort study was conducted including 51 adult heart transplant patients (n=32) and lung transplant patients (n=19) started on everolimus due to immunosuppressive therapy intolerance or failure, between 2010 and 2017. Everolimus indication, response, efficacy, and tolerability were assessed.ResultsEverolimus was most commonly initiated due to leukopenia/neutropenia (n=17, 33%) or renal dysfunction (n=13, 25%). Leukopenia/neutropenia resolved in 76% of patients (13 out of 17 patients). Renal function (GFR) increased 7.4 mL/min from baseline to 3 months after everolimus initiation (P=0.011). The most common adverse effects were edema (n=23, 45%) and hyperlipidemia (n=25, 49%). A high discontinuation rate was observed (n=21, 41%), mostly from edema.ConclusionsEverolimus might be beneficial in heart and lung transplant patients with leukopenia or neutropenia and lead to modest, short-term renal function improvement. Patient selection is crucial because adverse effects frequently lead to everolimus discontinuation.

Abstract 120: A Retrospective Study on Heart-lung Transplantation Patient Utilizing United Network for Organ Sharing Database to Identify the Effect of CMV Donor Recipient Serostatus, Age, Sex, or Anti-thymocyte Immunoglobulin Therapy on Mortality

Background: Heart-lung transplant is the treatment of choice for the end-stage disease to improve the survival and the overall quality of life. One of the major causes of the morbidity and hospitalization after the heart-lung transplant is cytomegalovirus (CMV) infection. The major determinant of CMV infection includes the donor (D) and recipient (R) serological status present (+) or absent (-) at the time of transplant. Different category of serostatus include high risk (D+/R-), intermediate risk (D+/R+, D-/R+) and low risk (D-/R). The risk of CMV infection is also related to the immunosuppressive protocol. Our aim was to identify if age, sex, or anti-thymocyte immunoglobulin (ATG) immunosuppressive therapy are associated with mortality in heart-lung transplant patients. Methods: We retrospectively analyzed heart-lung transplant patients identified within the United Network for Organ Sharing (UNOS) database. For mortality data, differences in donor-recipient CMV serostatus were evaluated using unadjusted and adjusted logistic regression models. SAS v. 9.4 was used for statistical analysis with p &lt; .05 used to indicate statistical significance. Results: Of the 79,015 patients who had a heart and/or lung transplant, CMV serostatus data was available for 49,294 patients (62%). All 49,294 patients had gender and age data; however, only 3,080 (6%) had ATG induction data. The overall mortality rate was 39%, with statistically significant differences in mortality rate observed between the low and intermediate risk groups (36% vs. 40%; p &lt; 0.001) and between the low and high risk groups (36% vs. 39%; p &lt; 0.001). After adjusting for age, sex, and ATG induction at discharge, low risk patients had 21% lower odds of dying compared to high risk patients (95% CI = 1% to 37%; p = 0.040). The effect of serostatus on mortality was not moderated by age, biological sex, or ATG induction at discharge. Finally, a 1% increase in the odds of dying was observed between patients who were one-year older at transplant ( p = 0.006), and patients who received ATG induction at discharge had 54% lower odds of dying relative to patients who did not receive ATG induction ( p &lt; 0.001). Conclusion: Serostatus had the exclusive effect on mortality with higher mortality rate in high risk group compared to low risk serostatus group. Young population group had lower mortality rate and ATG induction therapy tends to lower the mortality rate.

Ventriculitis due to infection with Rhizopus arrhizus

A 52-year-old heart–lung transplant patient presented to the emergency department with acute onset of neurologic symptoms. MRI showed ballooning of the left ventricle, midline shift and contrast enhancement in the anterior horn of the left ventricle. Ventricle neuroendoscopy revealed whitish, floccose aerial structures within the left ventricle. Brain biopsy cultures grew Rhizopus arrhizus. Therapy with liposomale amphotericin B and posaconazole was performed. Except for hemianopsia and deficits in minute motor activity, the patient completely recovered.

Low-dose computed tomography volumetry for subtyping chronic lung allograft dysfunction

The long-term success of lung transplantation is challenged by the development of chronic lung allograft dysfunction (CLAD) and its distinct subtypes of bronchiolitis obliterans syndrome (BOS) and restrictive allograft syndrome (RAS). However, the current diagnostic criteria for CLAD subtypes rely on total lung capacity (TLC), which is not always measured during routine post-transplant assessment. Our aim was to investigate the utility of low-dose 3-dimensional computed tomography (CT) lung volumetry for differentiating RAS from BOS. This study was a retrospective evaluation of 63 patients who had developed CLAD after bilateral lung or heart‒lung transplantation between 2006 and 2011, including 44 BOS and 19 RAS cases. Median post-transplant follow-up was 65 months in BOS and 27 months in RAS. The median interval between baseline and the disease-onset time-point for CT volumetry was 11 months in both BOS and RAS. Chronologic changes and diagnostic accuracy of CT lung volume (measured as percent of baseline) were investigated. RAS showed a significant decrease in CT lung volume at disease onset compared with baseline (mean 3,916 ml vs 3,055 ml when excluding opacities, p < 0.0001), whereas BOS showed no significant post-transplant change (mean 4,318 ml vs 4,396 ml, p = 0.214). The area under the receiver operating characteristic curve of CT lung volume for differentiating RAS from BOS was 0.959 (95% confidence interval 0.912 to 1.01, p < 0.0001) and the calculated accuracy was 0.938 at a threshold of 85%. In bilateral lung or heart‒lung transplant patients with CLAD, low-dose CT volumetry is a useful tool to differentiate patients who develop RAS from those who develop BOS.

Quantification of propionaldehyde in breath of patients after lung transplantation

Oxygen-derived free radicals (ROS) have been identified to contribute significantly to ischemia–reperfusion (I/R) injury by initiating chain reactions with polyunsaturated membrane lipids (lipid peroxidation, LPO) resulting in the generation of several aldehydes and ketones. Due to their volatile nature these LPO products can be measured noninvasively in breath. We hypothesized that one of these markers, namely propionaldehyde, will be increased in lung and heart–lung transplant patients where severe oxidative stress due to I/R injury with early graft dysfunction represents one of the major postoperative complications resulting in prolonged ventilation and increased in-hospital morbidity and mortality. Expiratory air measurements for acetone, isoprene, and propionaldehyde were performed in seven patients after lung (n=5) or heart–lung (n=2) transplantation, ventilated patients (n=12), and healthy volunteers (n=17) using online ion-molecule reaction mass spectrometry. Increased concentrations of acetone (transplanted: 3812 [2347–12498]; ventilated: 1255 [276–1959]; healthy: 631 [520–784] ppbv; P<.001) and propionaldehyde (transplanted: 270 [70–424]; ventilated: 82 [41.8–142]; healthy: 1.7 [0.1–11.8] ppbv; P<.001) were found in expiratory air of transplanted and ventilated patients. Propionaldehyde resulting from spontaneous fragmentation of peroxides due to free radical-induced LPO after I/R injury in patients after lung or heart–lung transplantation can be quantified in expired breath.

A computer simulation model of the cost-effectiveness of routine Staphylococcus aureus screening and decolonization among lung and heart-lung transplant recipients

Our objective was to model the cost-effectiveness and economic value of routine peri-operative Staphylococcus aureus screening and decolonization of lung and heart-lung transplant recipients from hospital and third-party payer perspectives. We used clinical data from 596 lung and heart-lung transplant recipients to develop a model in TreeAge Pro 2009 (Williamsport, MA, USA). Sensitivity analyses varied S. aureus colonization rate (5-15%), probability of infection if colonized (10-30%), and decolonization efficacy (25-90%). Data were collected from the Cardiothoracic Transplant Program at the University of Pittsburgh Medical Center. Consecutive lung and heart-lung transplant recipients from January 2006 to December 2010 were enrolled retrospectively. Baseline rates of S. aureus colonization, infection and decolonization efficacy were 9.6%, 36.7%, and 31.9%, respectively. Screening and decolonization was economically dominant for all scenarios tested, providing more cost savings and health benefits than no screening. Savings per case averted (2012 $US) ranged from $73,567 to $133,157 (hospital perspective) and $10,748 to $16,723 (third party payer perspective), varying with the probability of colonization, infection, and decolonization efficacy. Using our clinical data, screening and decolonization led to cost savings per case averted of $240,602 (hospital perspective) and averted 6.7 S. aureus infections (4.3 MRSA and 2.4 MSSA); 89 patients needed to be screened to prevent one S. aureus infection. Our data support routine S. aureus screening and decolonization of lung and heart-lung transplant patients. The economic value of screening and decolonization was greater than in previous models of other surgical populations.

Incidence of nosocomial pneumonia and risk of recurrence after antimicrobial therapy in critically ill lung and heart–lung transplant patients

Little is known about the resolution of symptoms of nosocomial pneumonia (NosoP) after lung and heart-lung transplantation. The aim of this study was to describe the clinical response to antimicrobial therapy in (ICU) patients with NosoP after lung or heart-lung transplantation. Between January 2008 and August 2010, 79 lung or heart-lung transplantations patients were prospectively studied. NosoPwas confirmed by quantitative cultures of bronchoalveolar lavage or endotracheal aspirates. Clinical variables, sequential organ failure assessment (SOFA) score, and radiologic score were recorded from start of therapy until day 9. Thirty-five patients (44%) experienced 64 episodes of NosoP in ICU. Fourteen patients (40%) had NosoP recurrence. Most frequently isolated organisms were Enterobacteriaceae (30%), Pseudomonas aeruginosa (25%), and Staphylococcus aureus (20%). Sequential organ failure assessment (SOFA) score improved significantly at day 6 and C-reactive protein level at day 9. SOFA and radiologic scores differed significantly between patients with and without NosoP recurrence at day 3 and 9. The ICU mortality rate did not differ between patients with and without NosoP recurrence, and free of NosoP (14.3%, 9.5%, 11.4%, respectively) (p=0.91). Severities of illness and lung injury were the two major risk factors for NosoP recurrence. Occurrence of NosoP has no impact on ICU mortality.

Simultaneous serum nicotine, cotinine, and trans-3′-hydroxycotinine quantitation with minimal sample volume for tobacco exposure status of solid organ transplant patients

Concentrations of nicotine and its metabolites in blood are indicative of patients' current tobacco exposure, and their quantifications have been clinically applied to multiple assessments including demonstration of abstinence prior to heart-lung transplantation. For the purpose of transplant evaluation, the laboratory work up is extensive; thereby an assay with minimal sample volume is preferred. We developed and validated a rapid LC-MS/MS assay to simultaneously quantitate nicotine and its major metabolites, Cotinine and trans-3'-OH-cotinine (3-OH-Cot), in serum. 100μL of serum was spiked with deuterated internal standards and extracted by Oasis HLB solid phase extraction cartridge. Nicotine and metabolites in the reconstituted serum extract were separated by Agilent Eclipse XDB-C8 3.5μm 2.1mm×50mm HPLC column within 4.7min, and quantified by MS/MS with positive mode electrospray ionization and multiple reaction monitoring. Ion suppression was insignificant, and extraction efficiency was 79-110% at 50ng/mL for all compounds. Limit of detection was 1.0ng/mL for nicotine and 3-OH-Cot, and <0.5ng/mL for Cotinine. Linearity ranges for nicotine, cotinine and 3-OH-Cot were 2-100, 2-1000, and 5-1000ng/mL with recoveries of 86-115%. Within-day and twenty-day imprecision at nicotine/cotinine/3-OH-Cot levels of 22/150/90, 37/250/150, and 50/800/500ng/mL were all 1.1-6.5%. The reconstituted serum extracts were stable for at least 7 days stored in the HPLC autosampler at 5°C. Our method correlates well with alternative LC-MS/MS methods. We successfully developed and validated an LC-MS/MS assay to quantitate concentrations of nicotine and its metabolites in serum with minimal sample volume to assess tobacco exposure of heart-lung transplant patients.

Atrial arrhythmias after lung and heart–lung transplant: Effects on short-term mortality and the influence of amiodarone

The incidence and effect of atrial fibrillation or flutter (AF) after lung transplant are variable. An effect of pharmacologic treatment on outcomes is undetermined. One hundred thirty-seven consecutive lung or heart-lung transplant patients were reviewed retrospectively. Uni- and multivariate analyses were performed to determine statistically significant risk factors for AF and short-term mortality. AF occurred in 45.0% of patients within 26 days. By univariate analysis, male gender was predictive of AF (hazard ratio [HR] = 2.25, 95% confidence interval [CI] 1.21 to 4.20, p = 0.011). Mortality within 200 days occurred in 36 of 137 (22.6%) patients. Those with AF had higher mortality than those without AF (27 of 62 [43.5%] vs 9 of 75 [12%]; p < 0.0001). Twenty-four of the 38 (63.1%) patients treated with amiodarone died, whereas 3 of 26 (11.5%) patients treated without amiodarone died (p < 0.0001). Mortality was similar among patients without AF, and those with AF not receiving amiodarone (9 of 75 [12%] vs 3 of 26 [11.5%], p = 1.00). By multivariate analysis, chronic obstructive pulmonary disease (HR = 0.395, CI 0.175 to 0.892, p = 0.025), primary pulmonary hypertension (HR = 7.245, CI 1.89 to 27.84, p = 0.0039), and use of amiodarone (HR = 2.967, CI 1.187 to 7.415, p = 0.020) were associated with death. Amiodarone was shown to be a significant statistical moderator (p < 0.0001) and mediator (p < 0.001) of mortality in AF patients. There was a high incidence of AF after lung or heart-lung transplant, and a significant increase in mortality in AF patients treated with amiodarone. In patients with severe lung pathology, amiodarone pulmonary toxicity may be more common than previously known, and may be a significant contributor to mortality. Amiodarone use should be restricted in the lung transplant patient population.

Supranormal Expiratory Airflow after Bilateral Lung Transplantation Is Associated with Improved Survival

flow volume loops (FVL) in some bilateral lung transplant (BLT) and heart-lung transplant (HLT) patients suggest variable extrathoracic obstruction in the absence of identifiable causes. These FVLs usually have supranormal expiratory and normal inspiratory flow rates (SUPRA pattern). characterize the relationship of the SUPRA pattern to predicted donor and recipient lung volumes, airway size, and survival. we performed a retrospective review of adult BLT/HLT patients. We defined the SUPRA FVL pattern as: (1) mid-vital capacity expiratory to inspiratory flow ratio (Ve50:Vi50) > 1.0, (2) absence of identifiable causes of extrathoracic obstruction, and (3) Ve50/FVC ≥ 1.5 s(-1). We calculated predicted total lung capacity (pTLC) ratio by dividing the donor pTLC by the recipient pTLC. We measured airway luminal areas on thoracic computer tomographic scans. We compared survival in patients with and without the SUPRA pattern. the SUPRA FVL pattern occurred in 56% of the 89 patients who qualified for the analysis. The pTLC ratio of SUPRA and non-SUPRA patients was 1.11 and 0.99, respectively (P = 0.004). A higher pTLC ratio was correlated with increased probability of the SUPRA pattern (P = 0.0072). Airway luminal areas were larger in SUPRA patients (P = 0.009). Survival was better in the SUPRA cohort (P = 0.009). the SUPRA FVL pattern was frequent in BLT/HLT patients. High expiratory flows in SUPRA patients could result from increased lung elastic recoil or reduced airway resistance, both of which could be caused by the pTLC mismatch. Improved survival in the SUPRA cohort suggests potential therapeutic approaches to improve outcomes in BLT/HLT patients.

Feasibility of laparoscopic Nissen fundoplication after pediatric lung or heart–lung transplantation: should this be the standard?

Five-year graft survival in the pediatric lung transplant (LTxp) population is less than 50%, with obliterative bronchiolitis (OB) the leading cause of death at 1, 3, and 5 years post-transplant. Bronchiolitis obliterans syndrome (BOS), defined using spirometry values, is the clinical surrogate for the histological diagnosis of obliterative bronchiolitis. Surgical correction of documented gastroesophageal reflux disease (GERD) has been proposed as a means to potentially delay the onset of BOS and prolong allograft survival in adults before or after lung transplantation but only one such study exists in children. We have examined the safety and possible benefits of laparoscopic antireflux surgery in pediatric patients following lung (LTxp) and heart-lung transplantation (HLTxp). An Institutional Review Board (IRB)-approved retrospective chart review was performed to evaluate the outcomes and complications of laparoscopic antireflux surgery in pediatric lung and heart-lung transplant patients. Spirometry data were collected for BOS staging using BOS criteria for children. Twenty-five lung and heart-lung transplants were performed between January 2003 and July 2009. Eleven transplant recipients, including six double-lung and five heart-lung (HLTxp), with a median age of 11.7 years (range 5.1-18.4 years), underwent a total of 12 laparoscopic Nissen fundoplications at a median of 427 days after transplant (range 51-2310 days). GERD was determined based upon clinical impression, pH probe study, gastric emptying study, and/or esophagram in all patients. Three patients already had a gastrostomy tube in place and two had one placed at the time of fundoplication. There were no conversions to open surgery, 30-day readmissions, or 30-day mortalities. Complications included one exploratory laparoscopy for free air 6 days after laparoscopic Nissen fundoplication for a gastric perforation that had spontaneously sealed. Another patient required a revision laparoscopic Nissen 822 days following the initial fundoplication for a paraesophageal hernia and recurrent GERD. The average length of hospital stay was 4.4 ± 1.7 days. Nine of the 12 fundoplications were performed in patients with baseline spirometry values prior to fundoplication and who could also complete spirometry reliably. One of these nine operations was associated with improvement in BOS stage 6 months after fundoplication; seven were associated with no change in BOS stage; and one was associated with a decline in BOS stage. It is feasible to perform laparoscopic Nissen fundoplication in pediatric lung and heart-lung transplant recipients without mortality or significant morbidity for the treatment of GERD. The real effect on pulmonary function cannot be assessed due to our small sample size and lack of reproducible spirometry in our younger patients. Additional studies are needed to elucidate the relationship between antireflux surgery and the potential for improving pulmonary allograft function and survival in children which has been previously observed in adult patients.

Predicting the graft survival for heart–lung transplantation patients: An integrated data mining methodology

Background Predicting the survival of heart–lung transplant patients has the potential to play a critical role in understanding and improving the matching procedure between the recipient and graft. Although voluminous data related to the transplantation procedures is being collected and stored, only a small subset of the predictive factors has been used in modeling heart–lung transplantation outcomes. The previous studies have mainly focused on applying statistical techniques to a small set of factors selected by the domain-experts in order to reveal the simple linear relationships between the factors and survival. The collection of methods known as ‘data mining’ offers significant advantages over conventional statistical techniques in dealing with the latter's limitations such as normality assumption of observations, independence of observations from each other, and linearity of the relationship between the observations and the output measure(s). There are statistical methods that overcome these limitations. Yet, they are computationally more expensive and do not provide fast and flexible solutions as do data mining techniques in large datasets. Purpose The main objective of this study is to improve the prediction of outcomes following combined heart–lung transplantation by proposing an integrated data-mining methodology. Methods A large and feature-rich dataset (16,604 cases with 283 variables) is used to (1) develop machine learning based predictive models and (2) extract the most important predictive factors. Then, using three different variable selection methods, namely, (i) machine learning methods driven variables—using decision trees, neural networks, logistic regression, (ii) the literature review-based expert-defined variables, and (iii) common sense-based interaction variables, a consolidated set of factors is generated and used to develop Cox regression models for heart–lung graft survival. Results The predictive models’ performance in terms of 10-fold cross-validation accuracy rates for two multi-imputed datasets ranged from 79% to 86% for neural networks, from 78% to 86% for logistic regression, and from 71% to 79% for decision trees. The results indicate that the proposed integrated data mining methodology using Cox hazard models better predicted the graft survival with different variables than the conventional approaches commonly used in the literature. This result is validated by the comparison of the corresponding Gains charts for our proposed methodology and the literature review based Cox results, and by the comparison of Akaike information criteria (AIC) values received from each. Conclusions Data mining-based methodology proposed in this study reveals that there are undiscovered relationships (i.e. interactions of the existing variables) among the survival-related variables, which helps better predict the survival of the heart–lung transplants. It also brings a different set of variables into the scene to be evaluated by the domain-experts and be considered prior to the organ transplantation.

ULCERATIVE ASPERGILLUS TRACHEOBRONCHITIS IN A STEM CELL TRANSPLANT PATIENT

INTRODUCTION: Aspergillus tracheobronchitis (ATB) is a rare manifestation of invasive aspergillosis. Various forms described include ulcerative, nodular-obstructing, and pseudomembranous. The ulcerative type is the least common and was first described in heart-lung and lung transplant patients. Ulcerative aspergillus involving the tracheobronchial tree has been described in AIDS patients. Nodular-obstructing and pseudomembranous tracheobronchitis have been described in lupus, diabetes, bone marrow transplant (BMT), and stem cell transplant (SCT) patients. We report the first case of ulcerative type in a SCT patient.

Repeat Heart–Lung Transplantation Outcome in the United States

This study compared risk-adjusted survival between primary and repeat heart-lung transplantation. Data for 799 primary heart-lung and 19 repeat heart-lung transplants were extracted from the United Network Organ Sharing (UNOS) registry. Analyses were based on propensity score matching in which 1, 2, and 3 primary transplant patients were matched with 19 repeat transplant patients. The matching variables were sex of recipient and donor, ethnicity, race, age of recipient and donor, cytomegalovirus status, ABO match, human leukocyte antigen mismatch, medical condition (hospitalized), ventilator, employment status, functional status, UNOS transplant status, and ischemic time. Propensity score matching revealed incomplete overlap of covariate distributions between primary and repeat transplant patients. The 19 repeat heart-lung transplant patients were more severely impaired at the time of transplant, and 4 did not have an adequate primary transplant match. For 15 repeat transplant patients, survival time was not significantly different from matched primary transplant controls. For repeat transplant patients, being Hispanic, having longer ischemic time, poor functional status (needing assistance), being hospitalized, and requiring ventilator support were all associated with decreased survival time; however, only being on a ventilator was statistically significant. By contrast, being female, and younger were associated with increased survival, but were not statistically significant. When matched for a set of potential confounding variables, no difference in survival benefit was observed between primary and repeat heart-lung transplant patients. The only predictor significantly associated with decreased survival time among repeat transplant patients was being on a ventilator.