Characteristics of donor lungs declined on site and impact of lung allocation policy change.

OBJECTIVE: National and institutional data suggest an increase in organ discard rate (donor lungs procured but not implanted) after a new lung allocation policy was introduced in 2017. However, this measure does not include on-site decline rate (donor lungs declined intraoperatively). The objective of this study is to examine the impact of the allocation policy change on on-site decline. METHODS: We used a Washington University (WU) and our local organ procurement organization (Mid-America Transplant [MTS]) database to abstract data on all accepted lung offers from 2014 to 2021. An on-site decline was defined as an event in which the procuring team declined the organs intraoperatively, and the lungs were not procured. Logistic regression models were used to investigate potentially modifiable reasons for decline. RESULTS: The overall study cohort comprised 876 accepted lung offers, of which 471 donors were at MTS with WU or others as the accepting center and 405 at other organ procurement organizations with WU as the accepting center. At MTS, the on-site decline rate increased from 4.6% to 10.8% (P = .01) after the policy change. Given the greater likelihood of non-local organ placement and longer travel distance after policy change, the estimated cost of each on-site decline increased from $5727 to $9700. In the overall group, latest partial pressure of oxygen (odds ratio [OR], 0.993; 95% confidence interval [CI], 0.989-0.997), chest trauma (OR, 2.474; CI, 1.018-6.010), chest radiograph abnormality (OR, 2.902; CI, 1.289-6.532), and bronchoscopy abnormality (OR, 3.654; CI, 1.813-7.365) were associated with on-site decline, although lung allocation policy era was unassociated (P = .22). CONCLUSIONS: We found that nearly 8% of accepted lungs are declined on site. Several donor factors were associated with on-site decline, although lung allocation policy change did not have a consistent impact on on-site decline.

Development and validation of the lung donor (LUNDON) acceptability score for pulmonary transplantation.

There is a chronic shortage of donor lungs for pulmonary transplantation due, in part, to low lung utilization rates in the United States. We performed a retrospective cohort study using data from the Scientific Registry of Transplant Recipients database (2006-2019) and developed the lung donor (LUNDON) acceptability score. A total of 83 219 brain-dead donors were included and were randomly divided into derivation (n = 58 314, 70%) and validation (n = 24 905, 30%) cohorts. The overall lung acceptance was 27.3% (n = 22 767). Donor factors associated with the lung acceptance were age, maximum creatinine, ratio of arterial partial pressure of oxygen to fraction of inspired oxygen, mechanism of death by asphyxiation or drowning, history of cigarette use (≥20 pack-years), history of myocardial infarction, chest x-ray appearance, bloodstream infection, and the occurrence of cardiac arrest after brain death. The prediction model had high discriminatory power (C statistic, 0.891; 95% confidence interval, 0.886-0.895) in the validation cohort. We developed a web-based, user-friendly tool (available at https://sites.wustl.edu/lundon) that provides the predicted probability of donor lung acceptance. LUNDON score was also associated with recipient survival in patients with high lung allocation scores. In conclusion, the multivariable LUNDON score uses readily available donor characteristics to reliably predict lung acceptability. Widespread adoption of this model may standardize lung donor evaluation and improve lung utilization rates.

Pulmonary Carcinoid Tumorlet in the Explanted Lungs for Lung Transplantation: A Case Series of 15 Patients.

BACKGROUND: Pulmonary carcinoid tumorlet (PCT) is defined as small proliferation of neuroendocrine cells that invade the adjacent basement membrane. It is often associated with chronic pulmonary inflammatory processes. However, the characteristics of PCT in end-stage lung diseases remain unclear. METHODS: We conducted a retrospective cohort study of the explanted lungs after transplantation at our institution between January 1999 and October 2020. Patients who underwent re-transplantation were excluded. RESULTS: Pulmonary carcinoid tumorlet was incidentally discovered in the explanted lungs from 15 patients (1.1%) out of 1367 lung transplants performed during the study period. Nine patients (60.0 %) were women, with a median age of 59 years (IQR: 57-62) at transplant. Underlying pulmonary indications for lung transplantation were chronic obstructive pulmonary disease (9/15, 60.0%), interstitial lung disease (2/15, 13.0%), pulmonary vascular disease (2/15, 13.0%), alpha-1 antitrypsin deficiency (1/15, 7.0%), and bronchiectasis (1/15, 7.0%). Of the patients who underwent bilateral lung transplantation (13/15, 86.7%), PCT was found in the right lung in 10 patients (10/13, 76.9%). Thirteen patients had one lesion, 1 patient had 2 lesions and 1 patient had multiple lesions. CONCLUSION: Our study shows that PCT is generally uncommon, but when it occurs, it occurs more frequently on the right side and in female patients with end-stage pulmonary disease. Chronic obstructive pulmonary disease may be a predisposing factor for developing PCT.

Outcomes of Extracorporeal Membrane Oxygenation for Primary Graft Dysfunction After Lung Transplantation.

BACKGROUND: Primary graft dysfunction (PGD) is the leading cause of death in the first 30 days after lung transplantation and is also associated with worse long-term outcomes. Outcomes of patients with PGD grade 3 requiring extracorporeal membrane oxygenation (ECMO) support after lung transplantation have yet to be well described. We sought to describe short- and long-term outcomes for patients with PGD grade 3 who required ECMO support. METHODS: This is a single-center retrospective cohort study of patients undergoing lung transplantation. We stratified patients with PGD grade 3 into non-ECMO, venoarterial (VA) ECMO, and venovenous (VV) ECMO groups after transplantation. We then compared the outcomes between the groups. RESULTS: Of 773 lung transplant recipients, PGD grade 3 developed in 204 (26%) at any time in the first 72 hours after lung transplantation. Of these, 13 (5%) required VA ECMO and 25 (10%) required VV ECMO support. The 30-day, 1-year, and 5-year survival in the VA ECMO group was 62%, 54%, and 43% compared with 96%, 84%, and 65% in the VV ECMO group and 99%, 94%, and 71% in the non-ECMO group. Multivariable Cox regression analysis showed that VA ECMO was associated with increased mortality (hazard ratio, 2.37; 95% CI, 1.06-5.28; P = .04). CONCLUSIONS: Patients who required VA ECMO support for PGD grade 3 have significantly worse survival compared with those who did not require ECMO and those who required VV ECMO support. This suggests that VA ECMO treatment of patients with PGD grade 3 after lung transplantation can be a predictable risk factor for mortality.

Electronic Health Record-Based Deep Learning Prediction of Death or Severe Decompensation in Heart Failure Patients.

BACKGROUND: Surgical mechanical ventricular assistance and cardiac replacement therapies, although life-saving in many heart failure (HF) patients, remain high-risk. Despite this, the difficulty in timely identification of medical therapy nonresponders and the dire consequences of nonresponse have fueled early, less selective surgical referral. Patients who would have ultimately responded to medical therapy are therefore subjected to the risk and life disruption of surgical therapy. OBJECTIVES: The purpose of this study was to develop deep learning models based upon commonly-available electronic health record (EHR) variables to assist clinicians in the timely and accurate identification of HF medical therapy nonresponders. METHODS: The study cohort consisted of all patients (age 18 to 90 years) admitted to a single tertiary care institution from January 2009 through December 2018, with International Classification of Disease HF diagnostic coding. Ensemble deep learning models employing time-series and densely-connected networks were developed from standard EHR data. The positive class included all observations resulting in severe progression (death from any cause or referral for HF surgical intervention) within 1 year. RESULTS: A total of 79,850 distinct admissions from 52,265 HF patients met observation criteria and contributed >350 million EHR datapoints for model training, validation, and testing. A total of 20% of model observations fit positive class criteria. The model C-statistic was 0.91. CONCLUSIONS: The demonstrated accuracy of EHR-based deep learning model prediction of 1-year all-cause death or referral for HF surgical therapy supports clinical relevance. EHR-based deep learning models have considerable potential to assist HF clinicians in improving the application of advanced HF surgical therapy in medical therapy nonresponders.

Acute Interstitial Pneumonia (Hamman-Rich Syndrome) in Lung Transplantation: A Case Series.

BACKGROUND: Acute interstitial pneumonia (AIP), also known as Hamman-Rich syndrome, is a rare and rapidly progressive idiopathic interstitial lung disease with a high mortality rate. Treatment is limited to supportive care and empirical high-dose steroids; however, outcomes are generally poor. There are few reports of lung transplantation (LTx) in patients with AIP. METHODS: We retrospectively identified patients with AIP among those who underwent LTx at our center between January 2008 and December 2020. RESULTS: During the study period, 4 patients with AIP underwent bilateral LTx: 3 men and 1 woman, between 30 and 57 years of age. The lung allocation score ranged between 71 and 89. Of the 4 patients, 2 needed extracorporeal membrane oxygenation and mechanical ventilation (MV) and 1 needed MV preoperatively. Time of onset to transplant ranged from 1 to 3 months. None of the patients had primary graft dysfunction after LTx; 2 had acute cellular rejection and 1 had chronic lung allograft dysfunction. The 4 patients are alive with survival ranging between 1 and 12 years after LTx. CONCLUSION: AIP should be considered in patients with acute respiratory failure without a clear etiology. Our study showed that LTx led to good outcomes and should be considered as a treatment option in appropriate candidates.

Clinical features and outcomes of unplanned single lung transplants.

OBJECTIVE: The decision to perform single lung transplants or double lung transplants is usually made before the operation. We have previously reported that a proportion of single lung transplants were unexpectedly performed in the setting of an aborted double lung transplant, and these patients may be at a higher risk of worse short-term outcomes. Long-term outcomes in unplanned single lung transplants remain unknown. METHODS: We analyzed a single-center database of lung transplants from 2000 to 2020. Single lung transplants were classified into planned and unplanned groups after reviewing operative notes. Root cause analysis was performed for unplanned single lung transplants. RESULTS: Of the 1326 lung transplants, 1265 (95%) were double lung transplants and 61 (5%) were single lung transplants (22 planned [36%], 39 unplanned [64%]). Underlying indications for transplant were significantly different; planned single lung transplant: chronic obstructive pulmonary disease (55%) and idiopathic pulmonary fibrosis (45%); unplanned single lung transplants: chronic obstructive pulmonary disease (23%), idiopathic pulmonary fibrosis (39%), and bronchiolitis obliterans syndrome (13%). The primary reasons for unplanned single lung transplant were donor-related (3, 7.7%), recipient-related (31, 80%), and donor and recipient-related factors (5, 13%). Unplanned single lung transplants were more likely to require cardiopulmonary bypass during the operation (planned: 4/22, 18% vs unplanned: 20/39, 51%) but had shorter ischemic times (planned: 251 ± 58 minutes vs unplanned: 221 ± 48 minutes). The 5-year overall survival was 53% in the planned and 58% in the unplanned groups, respectively (P = .323). No difference in chronic lung allograft dysfunction-free survival (P = .995) was observed. CONCLUSIONS: Unplanned single lung transplants in the setting of aborted double lung transplant may be associated with acceptable long-term outcomes.

Transplantation of Donor Lung With Partial Anomalous Pulmonary Venous Return Using a Carrel Patch.

Partial anomalous pulmonary venous return is a rare congenital aberrancy that involves oxygen-rich pulmonary venous drainage into the right atrium instead of into the systemic circulation. This report describes a case of isolated partial anomalous pulmonary venous return of the right upper lobe in a donor lung. Successful transplantation was performed with a Carrel patch technique for left atrial cuff reconstruction using a segment of donor vena cava. This report of partial anomalous pulmonary venous return in a right donor lung describes this reconstructive approach to restore physiologic venous drainage.

30 Years of Heart Transplant: Outcomes After Mechanical Circulatory Support From a Single Center.

BACKGROUND: Survival after bridge to transplantation with mechanical circulatory support (MCS) has yielded varying outcomes on the basis of device type and baseline characteristics. Continuous-flow left ventricular assist devices (CF-LVADs) have significantly improved waitlist mortality, but recent changes to the transplantation listing criteria have dramatically altered the use of MCS for bridge to transplantation. METHODS: Orthotopic heart transplantations from 1988 to 2019 at our institution (Washington University School of Medicine, Barnes-Jewish Hospital, St Louis, MO) were retrospectively reviewed and stratified by pretransplantation MCS status into CF-LVAD (n = 224), pulsatile LVAD (n = 49), temporary MCS (n = 71), and primary transplantation (n = 463) groups. Patients who underwent heart transplantation after the approval of CF-LVAD for bridge to transplantation and before the 2018 allocation policy changes underwent subgroup analysis to evaluate predictors of survival and complications in a contemporary cohort. RESULTS: Rates of primary transplantation declined from 88% to 14% over the course of the study. No significant difference in survival was detected in the cohort stratified by MCS status (P = .18). In the modern era, survival of patients treated with CF-LVADs and temporary MCS was noninferior to that seen with primary transplantation (P = .22). Notable predictors of long-term mortality included lower body mass index, peripheral vascular disease, previous coronary artery bypass graft, ABO nonidentical transplant, and increased donor age (all P ≤ .02). There were no differences in major postoperative complications. CONCLUSIONS: CF-LVAD has grown to account for the majority of transplantations at our center in the last decade, with no adverse effect on survival or postoperative complications. Temporary MCS increased after the 2018 listing criteria change, with acceptable early outcomes.

Association of STS database variables with repair durability in ischemic mitral regurgitation using machine learning.

BACKGROUND: Machine learning (ML) can identify nonintuitive clinical variable combinations that predict clinical outcomes. To assess the potential predictive contribution of standardized Society of Thoracic Surgeons (STS) Database clinical variables, we used ML to detect their association with repair durability in ischemic mitral regurgitation (IMR) patients in a single institution study. METHODS: STS Database variables (n = 53) served as predictors of repair durability in ML modeling of 224 patients who underwent surgical revascularization and mitral valve repair for IMR. Follow-up mortality and echocardiography data allowed 1-year outcome analysis in 173 patients. Supervised ML analyses were performed using recurrence (≥3+ IMR) or death versus nonrecurrence (<3+ IMR) as the binary outcome classification. RESULTS: We tested standard ML and deep learning algorithms, including support vector machines, logistic regression, and deep neural networks. Following training, final models were utilized to predict class labels for the patients in the test set, producing receiver operating characteristic (ROC) curves. The three models produced similar area under the curve (AUC), and predicted class labels with promising accuracy (AUC = 0.72-0.75). CONCLUSIONS: Readily-available STS Database variables have potential to play a significant role in the development of ML models to direct durable surgical therapy in IMR patients.

The Impact of Center Volume on Outcomes in Lung Transplantation.

BACKGROUND: Studies in lung transplantation have shown variable association between hospital volume and clinical outcomes. We aimed to identify the pattern of effect of hospital volume on individual patient survival after lung transplantation. METHODS: We performed a retrospective analysis using the United Network for Organ Sharing national thoracic organ transplantation database. Adult patients who underwent lung transplantation between January 2013 and December 2017 were included. The association between mean annual center volume and 1-year overall survival was examined using restricted cubic splines in a random effects multivariable Cox model. The volume threshold for optimal 1-year overall survival was subsequently approximated by the maximum likelihood approach using segmented linear splines in the same model. RESULTS: The study included 10,007 patients at 71 transplant centers. Median annual center volume was 22 cases (interquartile range, 10.6 to 38). A center volume threshold was identified at 33 cases per year (95% confidence interval, 28 to 37). Higher center volume, to 33 cases per year, was associated with better 1-year survival (hazard ratio 0.989, 95% confidence interval, 0.980 to 0.999 every additional case). Further increase in center volume above 33 cases per year showed no additional benefit (hazard ratio 1.000, 95% confidence interval, 0.996 to 1.003 every additional case). Twenty-three centers (32.4%) reached the volume threshold of 33 cases per year. CONCLUSIONS: One-year survival after lung transplantation improved with increasing center volume to as many as 33 cases per year. Low volume centers below the 33 cases per year threshold had large variations in their outcomes and had a higher risk of performing poorly, although many of them maintained good performance.

Competing Risks to Transplant in Bridging With Continuous-flow Left Ventricular Assist Devices.

BACKGROUND: Continuous-flow left ventricular assist device (CF-LVAD) support is a mainstay in the hemodynamic management of patients with end-stage heart failure refractory to optimal medical therapy. In this report we evaluated waitlist complications and competing outcomes for CF-LVAD patients compared with primary transplant candidates listed for orthotopic heart transplantation at a single center. METHODS: All patients listed for orthotopic heart transplantation between 2006 and 2020 at our institution were retrospectively reviewed (CF-LVAD, 300; primary transplant, 244). Kaplan-Meier methodology with log-rank testing was used to evaluate survival outcomes. Terminal outcomes of death, delisting, and transplant were assessed as competing risks and compared between groups using Gray's test. Multivariable Fine-Gray regression was used to identify predictors of transplantation. RESULTS: One-year rates of transplant, delisting, and death were 48%, 8%, and 2%, respectively, for CF-LVAD patients and 45%, 15%, and 9%, respectively, for primary transplant (all P < .001). Waitlist mortality at 5 years was 4% among CF-LVAD patients and 13% for primary transplants. All-cause mortality after listing was lower for CF-LVAD patients (P = .017). There was no difference in posttransplant survival between groups (P = .250). On multivariable Fine-Gray regression stroke (P = .017), respiratory failure (P = .032), right ventricular failure (P = .019), and driveline infection (P = .050) were associated with decreased probability of transplantation. Posttransplant survival was not significantly worse for CF-LVAD patients who experienced device-related complications (P = .901). CONCLUSIONS: Although device-related complications were significantly associated with decreased rates of transplant, CF-LVAD patients had excellent waitlist outcomes overall. In light of the 2018 allocation score change the risk of complications should be taken into account when deciding whether to offer CF-LVAD as a bridge to transplant.

Incidentally Detected Chronic Lymphocytic Leukemia in Hilar Lymph Nodes at the Time of Lung Transplantation: A Case Report.

A 68-year-old man with interstitial pulmonary fibrosis underwent bilateral lung transplantation. Histopathologic examination of hilar lymph nodes in the explanted lungs showed effacement of normal nodal architecture by the proliferation of small lymphocytes, consistent with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL). Unexpectedly discovered malignancies at the time of lung transplantation is uncommon, especially in the lymph nodes. The clinical management was challenging because of attempts to balance treatment of CLL and immunosuppressive treatment to prevent graft rejection. Here, we report a case of incidentally detected CLL in hilar lymph nodes with explanted lungs and review the relevant literature.

Clinical Features and Outcomes of Combined Pulmonary Fibrosis and Emphysema After Lung Transplantation.

BACKGROUND: Combined pulmonary fibrosis and emphysema (CPFE) is recognized as a characteristic syndrome of smoking-related interstitial lung disease that has a worse prognosis than idiopathic pulmonary fibrosis (IPF). However, outcomes after lung transplantation for CPFE have not been reported. The aim of this study is to describe the clinical features and outcomes of CPFE after lung transplantation. RESEARCH QUESTION: What are the clinical features and outcomes of CPFE after lung transplantation? STUDY DESIGN AND METHODS: This is a single-center retrospective cohort study of patients with CPFE and IPF who underwent lung transplantation at our center between January 2011 and December 2016. We defined CPFE as ≥10% emphysema in the upper lung fields combined with fibrosis on high-resolution CT scan. We characterized the clinical features of patients with CPFE and compared their outcomes after lung transplantation with those with IPF. RESULTS: Twenty-seven of 172 (16%) patients with IPF met criteria for CPFE. Severe pulmonary hypertension was present in 16 of 27 (59%) patients with CPFE. On logistic regression analysis, CPFE was significantly associated with primary graft dysfunction (PGD) grade 3 (OR, 3.14; 95% CI, 1.18-8.37; P = .02). On competing risk regression analysis, CPFE was associated with acute cellular rejection (ACR) grade ≥ A2, and chronic lung allograft dysfunction (CLAD) (hazard ratio [HR], 1.89; 95% CI, 1.10-3.25; P = .02; HR, 1.96; 95% CI, 1.02-3.77; P = .04, respectively). Five-year survival was 79.0% for the CPFE group and 75.4% for the IPF group (log-rank P = .684). INTERPRETATION: After transplantation, patients with CPFE were more likely to develop PGD, ACR, and CLAD compared with those with IPF. However, survival was not significantly different between the two groups.

Different-team procurements: A potential solution for the unintended consequences of change in lung allocation policy.

The new lung allocation policy has led to an increase in distant donors and consequently enhanced logistical burden of procuring organs. Though early single-center studies noted similar outcomes between same-team transplantation (ST, procuring team from transplanting center) and different-team transplantation (DT, procuring team from different center), the efficacy of DT in the contemporary era remains unclear. In this study, we evaluated the trend of DT, rate of transplanting both donor lungs, 1-year graft survival, and risk of Grade 3 primary graft dysfunction (PGD) using the Scientific Registry of Transplant Recipient (SRTR) database from 2006 to 2018. A total of 21619 patients (DT 2085, 9.7%) with 19837 donors were included. Utilization of DT decreased from 15.9% in 2006 to 8.5% in 2018. Proportions of two-lung donors were similar between the groups, and DT had similar 1-year graft survival as ST for both double (DT, HR 1.108, 95% CI 0.894-1.374) and single lung transplants (DT, HR 1.094, 95% CI 0.931-1.286). Risk of Grade 3 PGD was also similar between ST and DT. Given our results, expanding DT may be a feasible option for improving lung procurement efficiency in the current era, particularly in light of the COVID-19 pandemic.

Clinical Outcomes of Lung Transplants From Donors With Unexpected Pulmonary Embolism.

BACKGROUND: Pulmonary embolism (PE) is unexpectedly detected in some donor lungs during organ procurement for lung transplantation. Anecdotally, such lungs are usually implanted; however, the impact of this finding on recipient outcomes remains unclear. We hypothesized that incidentally detected donor PE is associated with adverse short-term and long-term outcomes among lung transplant recipients. METHODS: We analyzed a prospectively maintained database of all lung donors procured by a single surgeon and transplanted at our institution between 2009 and 2018. A standardized approach was used for all procurements and included antegrade and retrograde flush. Pulmonary embolism was defined as macroscopic thrombus seen in the pulmonary artery during the donor procurement operation. RESULTS: A total of 501 consecutive lung procurements were performed during the study period. The incidence of donor PE was 4.4% (22 of 501). No organs were discarded owing to PE. Donors with PE were similar to donors without PE in baseline characteristics and Pao2. Recipients in the two groups were also similar. Pulmonary embolism was associated with a higher likelihood of acute cellular rejection grade 2 or more (10 of 22 [45.5%] vs 120 of 479 [25.1%], P = .03). Multivariable Cox modeling demonstrated an association between PE and the development of chronic lung allograft dysfunction (hazard ratio 2.02; 95% confidence interval, 1.23 to 3.30; P = .005). CONCLUSIONS: Lungs from donors with incidentally detected PE may be associated with a higher incidence of recipient acute cellular rejection as well as reduced chronic lung allograft dysfunction-free survival. Surgeons must use caution when transplanting lungs with incidentally discovered PE. These preliminary findings warrant corroboration in larger data sets.

Donor management using a specialized donor care facility is associated with higher organ utilization from drug overdose donors.

Drug overdoses have tripled in the United States over the last two decades. With the increasing demand for donor organs, one potential consequence of the opioid epidemic may be an increase in suitable donor organs. Unfortunately, organs from donors dying of drug overdose have poorer utilization rates than other groups of brain-dead donors, largely due to physician and recipient concerns about viral disease transmission. During the study period of 2011 to 2016, drug overdose donors (DODs) account for an increasingly greater proportion of the national donor pool. We show that a novel model of donor care, known as specialized donor care facility (SDCF), is associated with an increase in organ utilization from DODs compared to the conventional model of hospital-based donor care. This is likely related to the close relationship of the SDCF with the transplant centers, leading to improved communication and highly efficient donor care.

Machine Learning Outcome Prediction in Dilated Cardiomyopathy Using Regional Left Ventricular Multiparametric Strain.

The clinical presentation of idiopathic dilated cardiomyopathy (IDCM) heart failure (HF) patients who will respond to medical therapy (responders) and those who will not (non-responders) is often similar. A machine learning (ML)-based clinical tool to identify responders would prevent unnecessary surgery, while targeting non-responders for early intervention. We used regional left ventricular (LV) contractile injury patterns in ML models to identify IDCM HF non-responders. MRI-based multiparametric strain analysis was performed in 178 test subjects (140 normal subjects and 38 IDCM patients), calculating longitudinal, circumferential, and radial strain over 18 LV sub-regions for inclusion in ML analyses. Patients were identified as responders based upon symptomatic and contractile improvement on medical therapy. We tested the predictive accuracy of support vector machines (SVM), logistic regression (LR), random forest (RF), and deep neural networks (DNN). The DNN model outperformed other models, predicting response to medical therapy with an area under the receiver operating characteristic curve (AUC) of 0.94. The top features were longitudinal strain in (1) basal: anterior, posterolateral and (2) mid: posterior, anterolateral, and anteroseptal sub-regions. Regional contractile injury patterns predict response to medical therapy in IDCM HF patients, and have potential application in ML-based HF patient care.

Impact of Nighttime Lung Transplantation on Outcomes and Costs.

BACKGROUND: Previous studies in the field of organ transplantation have shown a possible association between nighttime surgery and adverse outcomes. We aim to determine the impact of nighttime lung transplantation on postoperative outcomes, long-term survival, and overall cost. METHODS: We performed a single-center retrospective cohort analysis of adult lung transplant recipients who underwent transplantation between January 2006 and December 2017. Data were extracted from our institutional Lung Transplant Registry and Mid-America Transplant services database. Patients were classified into 2 strata, daytime (5 AM to 6 PM) and nighttime (6 PM to 5 AM), based on time of incision. Major postoperative adverse events, 5-year overall survival, and 5-year bronchiolitis obliterans syndrome-free survival were examined after propensity score matching. Additionally we compared overall cost of transplantation between nighttime and daytime groups. RESULTS: Of the 740 patients included in this study, 549 (74.2%) underwent daytime transplantation and 191 (25.8%) underwent nighttime transplantation (NT). Propensity score matching yielded 187 matched pairs. NT was associated with a higher risk of having any major postoperative adverse event (adjusted odds ratio, 1.731; 95% confidence interval, 1.093-2.741; P = .019), decreased 5-year overall survival (adjusted hazard ratio, 1.798; 95% confidence interval, 1.079-2.995; P = .024), and decreased 5-year bronchiolitis obliterans syndrome-free survival (adjusted hazard ratio, 1.556; 95% confidence interval, 1.098-2.205; P = .013) in doubly robust multivariable analyses after propensity score matching. Overall cost for NT and daytime transplantation was similar. CONCLUSIONS: NT was associated with a higher risk of major postoperative adverse events, decreased 5-year overall survival, and decreased 5-year bronchiolitis obliterans syndrome-free survival. Our findings suggest potential benefits of delaying NT to daytime transplantation.