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.

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.

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.

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.

Comparison of outcomes in lung and heart transplant recipients from the same multiorgan donor.

BACKGROUND: Primary graft dysfunction (PGD) and acute cellular rejection (ACR) are important causes of early morbidity and mortality following lung and heart transplantation. While many studies have elucidated donor-related risk factors of PGD and ACR, these complications often occur even with "ideal" donors. Therefore, we investigated potential associations of PGD and ACR between bilateral lung and heart transplant recipients from the same multiorgan donor, respectively. METHODS: Between 2011 and 2017, 100 donors contributed 100 bilateral lung transplants and 100 heart transplants performed. Logistic regression analysis for PGD and Cox proportional hazards regression analysis for ACR were used to estimate the relationship of heart and lung transplants. RESULTS: The incidence of PGD was 33% among lung and 17% among heart transplant recipients. Similarly, the incidence of ACR grade ≥ A2 for lung recipients was 38% (30/80), and the incidence of ACR grade ≥ 2R for heart recipients was 19% (15/80). There was no association between the development of PGD and ACR in lung and heart transplant recipients from the same donor, respectively. CONCLUSIONS: These findings suggest that inherent donor factors are not critical to the development of PGD and ACR after lung and heart transplantation.

Unintended consequences of changes to lung allocation policy.

Organ allocation for transplantation aims to balance the principles of justice and medical utility to optimally utilize a scarce resource. To address practical considerations, the United States is divided into 58 donor service areas (DSA), each constituting the first unit of allocation. In November 2017, in response to a lawsuit in New York, an emergency action change to lung allocation policy replaced the DSA level of allocation for donor lungs with a 250 nautical mile circle around the donor hospital. Similar policy changes are being implemented for other organs including heart and liver. Findings from a recent US Department of Health and Human Services report, supplemented with data from our institution, suggest that the emergency policy has not resulted in a change in the type of patients undergoing lung transplantation (LT) or early postoperative outcomes. However, there has been a significant decline in local LT, where donor and recipient are in the same DSA. With procurement teams having to travel greater distances, organ ischemic time has increased and median organ cost has more than doubled. We propose potential solutions for consideration at this critical juncture in the field of transplantation. Policymakers should choose equitable and sustainable access for this lifesaving discipline.

Implantation of left ventricular assist device in a patient with left ventricular non-compaction.

Left ventricular noncompaction (LVNC) may result in systolic left ventricular (LV) failure resulting in the need for heart transplantation. LV assist devices (LVAD) have been used to bridge these patients to transplantation; however, the extensive trabeculations found in these patients predispose them to thromboembolic events and pump thrombosis. We describe a patient with LVNC in whom an aggressive surgical approach was used to debride the LV cavity of trabeculations to successfully implant an LVAD.

Heterogeneity of systolic dysfunction in patients with severe aortic stenosis and preserved ejection fraction.

BACKGROUND AND AIM: Left ventricular (LV) systolic strain has been shown to be an early marker of LV dysfunction in patients with severe aortic stenosis (AS) despite preserved ejection fraction (EF). Echocardiography has provided useful data on regional LV strain patterns, but is not as sensitive as magnetic resonance imaging (MRI). No prior studies have used MRI-based strain analysis to characterize regional three-dimensional strain in patients with severe AS. METHODS: Twelve patients with severe AS and preserved EF underwent MRI-based multiparametric strain analysis. Circumferential and longitudinal strain values were calculated at individual points throughout the LV and analyzed in 12 discrete regions. Strain values were compared to a database of normal controls. RESULTS: Compared to control patients, circumferential strain in AS patients was significantly reduced at the base (P = 0.002), mid (P = 0.042), and inferior walls (P < 0.001). Longitudinal strain was significantly reduced at the base (P < 0.001), mid (P < 0.001), anterior (P < 0.001), and septal (P < 0.001) walls. Among patients with AS, there was heterogeneity in the location and severity of abnormalities in circumferential and longitudinal strains despite the presence of a preserved EF and lack of prior myocardial infarction. CONCLUSIONS: LV systolic strain is significantly impaired in patients with AS and preserved EF compared to healthy volunteers. Abnormalities in circumferential and longitudinal strains were heterogeneously distributed across the LV of patients with AS, allowing us to identify sentinel regions that may reflect the earliest signs of developing LV dysfunction.

Preliminary investigation of multiparametric strain Z-score (MPZS) computation using displacement encoding with simulated echoes (DENSE) and radial point interpretation method (RPIM).

PURPOSE: To describe and assess an automated normalization method for identifying sentinel (septal) regions of myocardial dysfunction in nonischemic, nonvalvular dilated cardiomyopathy (DCM), using an unprecedented combination of the navigator-gated 3D spiral displacement encoding with stimulated echoes (DENSE) magnetic resonance imaging (MRI), radial point interpolation (RPIM) and multiparametric strain z-score (MPZS). MATERIALS AND METHODS: Navigator-gated 3D spiral DENSE, in a 1.5T MRI machine, was used for acquiring the displacement encoded complex images, MR Analytical Software System (MASS) for automated boundary detection and automated meshfree RPIM for left-ventricular (LV) myocardial strain computation to analyze MPZS in 36 subjects (with n = 17 DCM patients). Pearson's r correlation established relations between global/sentinel MPZS and ejection fraction (EF). The time taken for combined RPIM-MPZS computations was recorded. RESULTS: Maximum MPZS differences were seen between anteroseptal and posterolateral regions in the base (2.0 ± 0.3 vs. 0.9 ± 0.5) and the mid-wall (2.1 ± 0.4 vs. 1.0 ± 0.4). These regional differences were found to be consistent with historically documented septal injury in nonischemic DCM. Correlations were 0.6 between global MPZS and EF, and 0.7 between sentinel MPZS and EF. The time taken for combined RPIM-MPZS computations per subject was 18.9 ± 5.9 seconds. CONCLUSION: Heterogeneous contractility found in the sentinel regions with the current automated MPZS computation scheme and the correlation found between MPZS and EF may lead to the creation of a new clinical metric in LV DCM surveillance. J. MAGN. RESON. IMAGING 2016;44:993-1002.

Three-dimensional regional strain computation method with displacement encoding with stimulated echoes (DENSE) in non-ischemic, non-valvular dilated cardiomyopathy patients and healthy subjects validated by tagged MRI.

PURPOSE: Fast cine displacement encoding with stimulated echoes (DENSE) MR has higher spatial resolution and enables rapid postprocessing. Thus we compared the accuracy of regional strains computation by DENSE with tagged MR in healthy and non-ischemic, non-valvular dilated cardiomyopathy (DCM) subjects. MATERIALS AND METHODS: Validation of three-dimensional regional strains computed with DENSE was conducted in reference to standard tagged MRI (TMRI) in healthy subjects and patients with DCM. Additional repeatability studies in healthy subjects were conducted to increase confidence in DENSE. A meshfree multiquadrics radial point interpolation method (RPIM) was used for computing Lagrange strains in sixteen left ventricular segments. Bland-Altman analysis and Student's t-tests were conducted to observe similarities in regional strains between sequences and in DENSE repeatability studies. RESULTS: Regional circumferential strains ranged from -0.21 ± 0.07 (Lateral-Apex) to -0.11 ± 0.05 (Posterorseptal-Base) in healthy subjects and -0.15 ± 0.04 (Anterior-Apex) to -0.02 ± 0.08 (Posterorseptal-Base) in DCM patients. Computed mean differences in regional circumferential strain from the DENSE-TMRI comparison study was 0.01 ± 0.03 (95% limits of agreement) in normal subjects, -0.01 ± 0.06 in DCM patients and 0.0 ± 0.02 in repeatability studies, with similar agreements in longitudinal and radial strains. CONCLUSION: We found agreement between DENSE and tagged MR in patients and volunteers in terms of evaluation of regional strains.

Left main disease progression following left branch vessel percutaneous intervention in patients who are referred for coronary artery bypass grafting.

BACKGROUND AND AIM OF THE STUDY: We studied patients presenting for coronary artery bypass grafting (CABG) with significant left main coronary artery disease (LMD) despite previously documented minimal or no LMD at percutaneous coronary intervention (PCI) for left-sided branch coronary artery disease. METHODS: Patients undergoing CABG for LMD with previous PCI were separated into fast or slow stenosis progression using percent change in LMD from first PCI to CABG divided by time (progression velocity). Outcomes and Kaplan-Meier survival were compared between the two groups. RESULTS: Between September 1997 and June 2010, 4837 patients underwent CABG with 1235 of them having previous PCI of which 118 had LMD and previous left-sided branch PCI. Using median progression velocity fast and slow progression groups were identified (0.53 ± 0.18 and 4.5 ± 4.8%/month, p < 0.001). Mean follow-up was 4.9 ± 3.6 years and 6.9 ± 3.9 years, respectively. Fast progression patients were younger (p = 0.042), with higher baseline LMD at PCI (16.4% vs. 9% stenosis, p = 0.025), and a mean of 2.5 years to LMD compared to 10.6 years for the slow group (p < 0.001). There was no difference between the groups in number or type of PCI and number or type of vessel intervened. Kaplan-Meier survival was similar at one, three, and five years. CONCLUSIONS: Fast LMD progression patients were younger and made up 4.7% (59/1235) of patients undergoing CABG with a history of PCI. Rapid progression was not related to number, type of PCI, or branch vessel intervened.

Radial artery free and T graft patency as coronary artery bypass conduit over a 15-year period.

BACKGROUND: The radial artery is often used as the second arterial graft for coronary artery bypass grafting. Little is known about the differences in long-term patency between radial free and T grafts. This study was performed to determine long-term radial artery patency over a 15-year period. METHODS AND RESULTS: Radial arteries were used as free grafts or T grafts for coronary artery bypass grafting over a 15-year period. Patients were contacted to determine if postoperative cardiac catheterization was performed and examination of any reports and films was performed. Grafts were graded as patent, luminal irregularity, or occluded. Each sequential graft was counted separately. Between September 1993 and December 2008, 13,926 patients underwent isolated coronary artery bypass grafting and 3248 patients had at least one radial artery graft used as a conduit. Catheterizations were performed at a mean of 7.4 ± 3.8 years (range, 3 days to 14.4 years) on 372 radial artery grafts (103 free and 269 T) in 215 patients. Kaplan-Meier freedom from occlusion for radial free and T grafts at 1 and 10 years was 97.1% and 75.4% and 99.6% and 62.9%, respectively (P=0.146 free versus T). Kaplan-Meier survival to 15 years was not statistically different between free and T graft patients (P=0.5). CONCLUSIONS: In 215 patients with postoperative catheterization after coronary artery bypass grafting with a radial artery graft, radial free and T grafts had similar and acceptable long-term patency to support their use as a coronary artery bypass graft conduit.

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.

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.

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.

MRI-based multiparametric strain analysis predicts contractile recovery after aortic valve replacement for aortic insufficiency.

BACKGROUND: Guidelines for referral of chronic aortic insufficiency (AI) patients for aortic valve replacement (AVR) suggest that surgery can be delayed until symptoms or reduction in left ventricular (LV) contractile function occur. The frequent occurrence of reduced LV contractile function after AVR for chronic AI suggests that new contractile metrics for surgical referral are needed. METHODS: In 16 chronic AI patients, cardiac MRI tagged images were analyzed before and 21.5 ± 13.8 months after AVR to calculate LV systolic strain. Average measurements of three strain parameters were obtained for each of 72 LV regions, normalized using a normal human strain database (n = 63), and combined into a composite index (multiparametric strain z score [MSZ]) representing standard deviation from the normal regional average. RESULTS: Preoperative global MSZ (72-region average) correlated with post-AVR global MSZ (R(2) = 0.825, p < 0.001). Preoperative global MSZ also predicts improvement of impaired regions (N = 271 regions from 14 AI patients, R(2) = 0.392, p < 0.001). Preoperative MRI-based LV ejection fraction (LVEF) is also predictive (r = 0.410, p < 0.001). Although global preoperative MSZ had a significantly higher correlation than preoperative LVEF with improvement of injured regions (p < 0.001), both measures convey the same phenomenon. CONCLUSIONS: Global preoperative MRI-based multiparametric strain predicts global strain postoperatively, as well as improvement of regions (n = 72 per LV) with impaired contractile function. Global contractile function is an important correlate with improvement in regionally impaired contractile function, perhaps reflecting total AI volume-overload burden (severity/duration of AI).

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.

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.

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.