Primary Heart Transplantation Research Articles

Treatment Results of LVAD Implantation and Heart Transplantation for Oncotherapy Induced Cardiomyopathy in Women and Men

<h3>Purpose</h3> Due to the increase of patient's survival after different types of malignancies, patient's cardiovascular morbidity during these treatments is rising in mid and long term. Heart failure is one of these entities- mainly due to the increasing complexity of chemotherapeutic substances and preexisting heart disease. <h3>Methods</h3> We retrospectively analyzed our patient's files to assess the options and outcome of HF therapies after tumor related therapy. <h3>Results</h3> Out of 450 patients treated at our institution for HF after oncological therapy 46 pts. (14 female/32 male) received advanced surgical heart failure therapy as LVAD implantation and/or and heart transplantation (HTx). The individual types of tumor and the timeline of individual therapies will be reported. Heart transplantation was considered to be possible again 5 years after tumor treatment and recurrence free oncological follow up. Surgical procedures took place during Jan 2011 and May 2021. At the time point of tumor diagnosis, women were 37,9 ± 12 years of age and developed severe heart failure 10,25 ± 4 years later. Men at time point of tumor diagnosis, were 44 ± 16 years. Terminal heart failure was diagnosed and surgically treated 7,2 ± 4 years later in men. This age related disparity is due to different carcinoma entities among men and women. 35 patients received an LVAD exclusively. 3 patients recovered from VAD. 7 patients initially received LVAD followed by subsequent HTx in 4 cases. 3 pts. still are listed for Htx. Four patients underwent primary heart transplantation. Preexisting heart failure was present in 5 % of women and 7 % of men prior to the diagnosed malignancy. 80 % of women and 72 % of men are alive. <h3>Conclusion</h3> Terminal heart failure is one the leading morbidities in oncological patients in mid and long term caused by available treatment options. Higher age and better survival make advanced HF therapies (LVAD/HTx) possible with reasonable results. Patients should be referred early to evaluate these specific options.

Geographic Variation in Heart Transplant Extended Criteria Donors in the United States

BackgroundRecent research has explored the use of higher risk extended criteria donors (ECDs) as a means of expanding the donor pool for heart transplantation. Here we sought to explore the current geographic distribution and survival outcomes of ECD utilization in various regions across the United States. MethodsThe United Network for Organ Sharing database was retrospectively queried for adult primary heart transplantation from 2000 to 2019. The EXPAND trial definition of ECD was used: ischemic time ≥ 4 hours, ejection fraction < 50%, age > 55 years, and history of coronary artery disease. Geographic data and 2019 population estimates were obtained from the US Census Bureau. ResultsOf the 42 642 transplants included in our analysis, 11 750 (27.6%) used ECDs. Region utilization of ECDs ranged from 18.4% to 46.5% of transplants. Region 6 had the highest utilization rate at 46.5%; this was primarily driven by the number of transplants with ischemic time ≥ 4 hours. Region 6 encompasses the largest total area (1.08 million square miles) and smallest population density (15.6 people per square mile). Region 8 had the lowest marginal donor utilization rate at 18.4%. Regions with high utilization of low ejection fractions, older donors, and donors with coronary artery disease (ie, regions 1 and 2) were able to maintain an average utilization rate of ECDs by maintaining short ischemic times. ConclusionsLarge discrepancies in the use of ECDs exist across the different United Network for Organ Sharing regions. This is primarily driven by longer ischemic times, likely guided by variance in population densities between different regions.

Matching Donor and Recipient Size in Pediatric Heart Transplantation.

Previous analyses in pediatric heart transplant (HT) recipients using weight or height have not found donor-recipient size-mismatch to be associated with post-transplant mortality. A recent study in 3,215 normal US children developed an equation for left ventricular (LV) mass using body surface area (BSA). We assessed whether donor-recipient size match using predicted LV mass (PLM) is associated with post-transplant in-hospital mortality or 1-year graft survival. We identified 4,717 children <18yrs old who received primary HT in the US during 01/2000 to 03/2015 and divided them into five groups [10%, 10%, 60% (reference group), 10% and 10%, respectively] with increasing donor-recipient PLM ratio. In adjusted analysis, group 1 children (PLM ratio ≤.90) were at higher risk of post-transplant in-hospital mortality [Odds Ratio (OR) 1.55, 95% CI 1.04, 2.31]. This association of the most undersized donors with recipient in-hospital mortality was similar when donor-recipient weight ratio<.88 or BSA ratio<.92 (lowest decile) were used instead. There was no difference in 1-year graft survival among groups. Utilizing donors with donor-recipient PLM ratio ≤.90 is associated with higher risk of early post-transplant mortality in pediatric HT recipients. However, this metric is not superior to donor-recipient weight ratio or BSA ratio for assessing size match.

Obesity and dyslipidemia predict cardiac allograft vasculopathy and graft loss in children and adolescents post-heart transplant: A PHTS multi-institutional analysis.

Obesity and dyslipidemia afflict children of all ages. We explored the prevalence of obesity and dyslipidemia in pediatric heart transplant (HT) recipients and its effects on cardiac allograft vasculopathy (CAV) and survival. This study included primary HT recipients (≤18years) transplanted between 01/1996 and 12/2018 included in the Pediatric Heart Transplant Society database. Obesity was categorized according to WHO/CDC guidelines and dyslipidemia according to the National Cholesterol Education Program. Kaplan-Meier analyses for CAV and graft loss stratified for BMI and lipid panels were generated and risk factors identified using multivariate analyses. Among 6291 HT patients (median age [range] at HT=4.3 [0.6-12.8]years; 45% Female; 68% White), 56% had a normal BMI at HT. Obese patients at HT had an increased risk for graft loss (HR 1.19, 95% CI 1.01-1.4, p=.04). Poor total cholesterol (TC), LDL-C, and TG were associated with the risk of both CAV (HR 1.79, p<.0001; HR 1.65, p=.0015; HR 1.53, p<.0001, respectively) and graft loss (HR 1.58, p=.0008; HR 1.22, p=.04; HR 1.43, p=.0007, respectively). Pediatric patients who are obese at the time of HT and dyslipidemic at 1year post-HT are at an increased risk for CAV and graft loss. Preventative interventions may reduce morbidity and mortality among this cohort.

Abstract 10073: Characterization of Mechanical Circulatory Support in Peripartum Cardiomyopathy

Introduction: Peripartum cardiomyopathy (PPCM) is a severe complication of pregnancy which is hallmarked by non-ischemic reduction in left ventricular ejection fraction (LVEF) to &lt;45% late in gestation or shortly postpartum. This study evaluated outcomes among women who required mechanical circulatory support (MCS) for end-stage heart failure in the setting of PPCM. Methods: Thirty female patients 18-46 years of age underwent cardiac surgery for PPCM between 2012-2020. Primary heart transplant patients (n=2) were excluded. PPCM patients with a new MCS requirement (n=28) were classified by device type and escalations in device support. Results: Mean age was 29±7 years and 21 patients (75%) were African American. Median time from delivery to MCS requirement was 418 [91-1201] days. Nineteen (68%) patients required temporary MCS (tMCS): 12 (63%) on intraaortic balloon pump, 9 (47%) on veno-arterial extracorporeal membrane oxygenation, and 4 (21%) on Impella. Nine (32%) patients underwent left ventricular assist device (LVAD) implant after failure of medical therapy. LVEF and left ventricular end-diastolic diameter (LVEDD) at MCS insertion were 14±5mm and 68±11mm, respectively. LVEF progressed to 24%±16% post-insertion and 29%±17% one year (Figure 1). Of the 19 tMCS patients, 5 (26%) required escalations with additional modalities. Ten (53%) patients were bridged to durable LVAD. Complications included right ventricular failure (n=4), stroke (n=2), sepsis (n=1), dialysis (n=5), and cardiac arrest (n=3). Duration of support was 9±7 days for tMCS and 996±625 days for LVAD. Overall survival to discharge was 89% (n=25). Twelve patients underwent transplant (43%) and two (7%) recovered native heart function. Conclusions: Severe PPCM can be effectively managed with tMCS as a bridging strategy to either transplant or durable LVAD. Patients will often require multiple escalations in resource-intensive therapy, but outcomes are excellent with vigilant management.

Contemporary outcomes of durable ventricular assist devices in adults with congenital heart disease as a bridge to heart transplantation.

This study aimed to compare the clinical characteristics, risk factors, and overall survival outcomes in adults with congenital heart disease (ACHD) bridged to transplantation with a ventricular assist device (VAD) versus no-VAD. The study included 894 ACHD patients aged ≥18years listed for primary heart transplantation between 2010 and 2019 from the United Network for Organ Sharing database. Primary outcomes were waitlist and 1-year post-transplant mortality between VAD and no-VAD ACHD patients. Of 894 ACHD patients included in the study, 91(10.1%) had VAD support at the time of listing. Patients who needed VAD support were mostly males, heavier, and had higher pulmonary artery pressure than the no-VAD group at the listing. The overall waitlist mortality was 38% in the VAD group than 17% in the no-VAD group (p<0.01). ECMO use was associated with significantly higher mortality than either group. There was no significant difference in 1-year post-transplant mortality between VAD versus no-VAD at the time of transplant (15% vs. 17%; p=0.66). Multivariate regression analysis found that BMI <20kg/m2 (hazard ratio (HR) 1.1; p=0.01), bilirubin >2mg/dl (HR 1.1; p=0.03), creatinine >2mg/dl (HR 1.3; p=0.04) and ECMO at transplant (HR 1.4; p=0.03) increased early post-transplant mortality. The one-year post-transplant mortality rate was no different for ACHD patients that received VAD versus no-VAD. These findings suggest that a VAD should be considered an option to support ACHD patients as a bridge to heart transplantation.

Redo orthotopic heart transplantation in the current era

ObjectiveThis study aims to investigate the trends, outcomes, and risk factors for mortality after redo orthotopic heart transplantation. MethodsThe United Network for Organ Sharing registry was used to identify adult orthotopic heart transplantation recipients from 2000 to 2020 and stratify into primary and redo cohorts. Five-year post-transplant survival was compared between 2 propensity-matched cohorts. Multivariable modeling was performed to identify risk-adjusted predictors of redo post-transplant mortality, both conditional and nonconditional on shorter-term survival. ResultsA total of 40,711 recipients were analyzed, 39,657 (97.4%) primary and 1054 (2.6%) redo. Redo recipients had a lower median age and were more frequently bridged with intravenous inotropes, intra-aortic balloon pump, or extracorporeal membrane oxygenation (all P < .05). One- and 5-year survivals were lower after redo orthotopic heart transplantation (90.0% vs 83.4% and 77.6% vs 68.6%, respectively) and remained lower after comparing 2 propensity-matched cohorts. Multivariable modeling found factors such as increasing donor age and graft ischemic times, along with pretransplant mechanical ventilation and blood transfusion, to negatively affect 90-day survival. Contingent on 1-year survival, donor factors such as hypertension (hazard ratio, 1.51; 95% confidence interval, 1.15-2.00, P = .004) and left ventricular ejection fraction less than 50% (hazard ratio, 2.22, 95% confidence interval, 1.16-4.24, P = .016) negatively affected survival at 5 years. ConclusionsAlthough infrequently performed, redo orthotopic heart transplantation remains associated with worse post-transplant outcomes compared with primary orthotopic heart transplantation. Although several high-risk features were identified to affect post-retransplant outcomes in the acute perioperative period, donor characteristics such as hypertension and decreased ejection fraction continue to have lasting negative impacts in the longer term.

Resultados del retrasplante cardiaco: subanálisis del Registro Español de Trasplante Cardiaco

Introduction and objectivesHeart retransplantation (ReHT) is controversial in the current era. The aim of this study was to describe and analyze the results of ReHT in Spain. MethodsWe performed a retrospective cohort analysis from the Spanish Heart Transplant Registry from 1984 to 2018. Data were collected on donors, recipients, surgical procedure characteristics, immunosuppression, and survival. The main outcome was posttransplant all-cause mortality or need for ReHT. We studied differences in survival according to indication for ReHT, the time interval between transplants and era of ReHT. ResultsA total of 7592 heart transplants (HT) and 173 (2.3%) ReHT were studied (median age, 52.0 and 55.0 years, respectively). Cardiac allograft vasculopathy was the most frequent indication for ReHT (42.2%) and 59 patients (80.8%) received ReHT >5 years after the initial transplant. Acute rejection and primary graft failure decreased as indications over the study period. Renal dysfunction, hypertension, need for mechanical ventilation or intra-aortic balloon pump and longer cold ischemia time were more frequent in ReHT. Median follow-up for ReHT was 5.8 years. ReHT had worse survival than HT (weighted HR, 1.43; 95%CI, 1.17-1.44; P<.001). The indication of acute rejection (HR, 2.49; 95%CI, 1.45-4.27; P<.001) was related to the worst outcome. ReHT beyond 5 years after initial HT portended similar results as primary HT (weighted HR, 1.14; 95%CI, 0.86-1.50; P<.001). ConclusionsReHT was associated with higher mortality than HT, especially when indicated for acute rejection. ReHT beyond 5 years had a similar prognosis to primary HT.

Favorable outcomes after heart transplantation in Barth syndrome

Barth Syndrome (BTHS) is a rare, X-linked disease characterized by cardioskeletal myopathy and neutropenia. Comparative outcomes after heart transplantation have not been reported. We identified BTHS recipients across 3 registries (Pediatric Heart Transplant Study Registry [PHTS], Barth Syndrome Research Registry and Repository, and Scientific Registry of Transplant Recipient-Pediatric Health Information System) and matched them 1:4 to non-BTHS, male heart transplant (HT) recipients listed with dilated cardiomyopathy in PHTS. Demographics and survival data were analyzed for all recipients, whereas post-HT infection, malignancy, allograft vasculopathy, and acute rejection were only available for analysis for individuals with PHTS data. Forty-seven BTHS individuals with 51 listings and 43 HTs (including 2 re-transplants) were identified. Age at primary HT was 1.7 years (IQR: 0.6-4.5). Mechanical circulatory support at HT was common (ventricular assist device 29%, extracorporeal membrane oxygenation 5%). Over a median follow-up of 4.5 years (IQR 2.7-9.1), survival for BTHS HT recipients was no different than non-BTHS HT recipients (HR 0.91, 95% CI 0.40-2.12, p=0.85). Among those with PHTS data (n=28), BTHS HT recipients showed no difference in freedom from infection (HR 0.64, 0.34-1.22; p=0.18), malignancy (HR 0.22, 0.02-2.01, p=0.18), and allograft vasculopathy (HR 0.58, 0.16-2.1, p=0.41). Freedom from acute rejection (HR 0.39, 0.17-0.86, p=0.02) was greater for BTHS HT recipients despite similar use of induction (61 vs 73%, p=0.20), steroids at 30-days (75 vs 62%, p=0.27), and dual/triple drug immunosuppression at 1-year (80 vs 84%, p=0.55). In this largest cohort yet reported, individuals with BTHS have equivalent survival with less acute rejection and no difference in infection or malignancy after HT. When indicated, HT for individuals with BTHS is appropriate.

Results of heart retransplantation: subanalysis of the Spanish Heart Transplant Registry

Introduction and objectivesHeart retransplantation (ReHT) is controversial in the current era. The aim of this study was to describe and analyze the results of ReHT in Spain. MethodsWe performed a retrospective cohort analysis from the Spanish Heart Transplant Registry from 1984 to 2018. Data were collected on donors, recipients, surgical procedure characteristics, immunosuppression, and survival. The main outcome was posttransplant all-cause mortality or need for ReHT. We studied differences in survival according to indication for ReHT, the time interval between transplants and era of ReHT. ResultsA total of 7592 heart transplants (HT) and 173 (2.3%) ReHT were studied (median age, 52.0 and 55.0 years, respectively). Cardiac allograft vasculopathy was the most frequent indication for ReHT (42.2%) and 59 patients (80.8%) received ReHT >5 years after the initial transplant. Acute rejection and primary graft failure decreased as indications over the study period. Renal dysfunction, hypertension, need for mechanical ventilation or intra-aortic balloon pump and longer cold ischemia time were more frequent in ReHT. Median follow-up for ReHT was 5.8 years. ReHT had worse survival than HT (weighted HR, 1.43; 95%CI, 1.17-1.44; P<.001). The indication of acute rejection (HR, 2.49; 95%CI, 1.45-4.27; P<.001) was related to the worst outcome. ReHT beyond 5 years after initial HT portended similar results as primary HT (weighted HR, 1.14; 95%CI, 0.86-1.50; P<.001). ConclusionsReHT was associated with higher mortality than HT, especially when indicated for acute rejection. ReHT beyond 5 years had a similar prognosis to primary HT.

The Direct Route, Alternative Paths, and Informing the Future Directions of Single Ventricle Palliation

The treatment of single ventricle congenital heart disease through staged, surgical palliation to Fontan circulation is now widely accepted as the best route to years of high-quality life. The recent era’s improved survival through and following Fontan palliation is a remarkable achievement for pediatric cardiothoracic surgeons and cardiologists. The short- and midterm outcomes AFTER Fontan palliation are now such that proponents of the main alternative pathway for single ventricle diseases, primary heart transplant, are relatively infrequently heard from for standard risk disease.

Outcomes of Heart Transplant Recipients Bridged with Percutaneous versus Durable LVADs

<h3>Purpose</h3> The new UNOS heart allocation policy prioritizes patients with percutaneous ventricular support devices over durable LVADs. We examined one-year survival of heart transplant recipients successfully bridged with Impella versus durable LVADs in the most recent era. <h3>Methods</h3> We retrospectively reviewed all primary adult orthotopic heart transplant recipients in the UNOS registry between Jan 1, 2016 to June 12, 2020. Recipients were identified as having an isolated durable LVAD or Impella device at the time of transplant. Those bridged with ECMO, RVAD, BIVAD, or TAH were excluded. One-year survival was examined with the Kaplan Meier method and multivariable Cox proportional hazards regression. <h3>Results</h3> Of 10,492 heart transplant recipients in the study period, 4610(44%) were bridged with a durable LVAD and 158(2%) with Impella. Impella use increased following the UNOS allocation policy change (3% vs 1% of transplants, p<0.01) and a higher proportion were status 1 or 2 compared to those bridged with durable LVADs (96% vs 26%, p<0.01). Median days between listing and transplant were 40, 218, and 13 days for no MCS, durable LVAD, and Impella, respectively (p<0.01). Impella-bridged recipients were less likely to be obese (26% vs 41%, p<0.01), have diabetes (24% vs 31%, p<0.01), ischemic cardiomyopathy (28% vs 35%, p<0.01), prior cardiac surgery (27% vs 73%, p<0.01), and were more likely to be on inotropes at the time of transplant (65% vs 6%, p<0.01). On multivariate analysis, neither bridge with durable LVAD (aHR 1.25, 95% CI 0.97-1.62, p = 0.08) nor Impella (aHR 1.07, 95% CI 0.55-2.08, p=0.84) was associated with a difference in one-year survival following heart transplantation. <h3>Conclusion</h3> Impella utilization as bridge to transplant has tripled in the current era of heart transplantation with no significant difference in one-year survival compared to those bridged with durable LVADs. Percutaneous LVAD platforms can be cautiously considered in the sickest patients requiring LVAD bridge to transplantation.

Sex-Related Temporal Trends in Donor and Recipient Profile and Outcome after Heart Transplantation: Analysis of the ISHLT Registry

<h3>Purpose</h3> The complex interactions between recipient and donor risk factors play a critical role in heart transplantation (HT) outcomes, particularly in light of the changing clinical phenotypes of candidates and donors and the continuing improvements and utilization of evidence-based therapies in women. The aim of this study was to explore temporal sex-related changes in recipient and donor features and effect of sex on HT outcomes. <h3>Methods</h3> We performed an analysis of the ISHLT Registry including primary adult HT performed in 1996-2018. We built a multivariable regression model which explored the likelihood of a set of high-risk clinical characteristics (Figure 1A) to be prevalent in earlier vs later years. We treated transplant year as a continuous variable and the analysis was stratified by sex. Interaction terms of recipient sex and each variable were used to identify differences between male and female recipient sex. <h3>Results</h3> Among 86,307 recipients, there were 19,983 women and 66,324 men. The proportion of transplanted women increased from 19% in 1996 to 27% in 2018 (p<0.001). Recipient and donor characteristics changed significantly over time. This change has been similar for both male and female recipients, with the exception of women with diabetes and history of dialysis having lower likelihood of transplant and women with recent infection having higher likelihood of transplant (Figure 1A). A significant reduction in 5-year mortality and 5-year malignancy rate after transplant was seen over the years. There were no significant sex-related differences in the degree of mortality and malignancy improvement (p=NS for interaction with sex, Figure 1B). <h3>Conclusion</h3> The proportion of women receiving HT has increased. Among those transplanted, there does not appear to be significant sex disparities, as evidenced by similar recipient and donor profiles and a similar improvement of survival and post-transplant malignancy rates in both male and female recipients.

Heart Transplant Waitlist Outcomes and Wait Time by Center Volume: Where Should You List?

Purpose With new devices and policy changes in the heart transplantation, patients are faced with increasingly complex management options. Among one of the decisions they must make is which transplant center they can and should list under. Here we explored waitlist outcomes by transplant center volume. Methods We performed a retrospective analysis of adults listed for primary heart transplantation from 2008 to 2018 using the UNOS Database. Transplant centers were split into low ( 30 HTx/year) volume. Multivariable Cox Proportional Hazards analysis identified predictors of death prior to transplantation; Cox model was adjusted for age at listing, transpulmonary gradient, and use of LVAD while on the waitlist. Results Of the 37,779 patients included in our study, only 24,285 (64.3%) underwent transplantation. Of the remaining 13,494, 6,687 (49.6% of non-transplanted patients) died before receiving transplantation. Of the 140 centers, 51 were low volume (1,412 HTx), 64 were medium volume (11,687 HTx), and 25 were high volume (11,186 HTx); 118 patients were listed at centers which did not perform any transplants in the years analyzed. LVAD utilization (at listing or while listed) was 20.2% for low, 31.8% for medium, and 25.1% for high volume centers. Of the 3,192 patients listed in low-volume centers, only 1,412 (44.2%) underwent transplantation, while 800 (25.1%) died prior to transplant; of the 18,538 listed in medium volume centers, 11,687 (63.0%) underwent transplantation, while 3,343 (18.0%) died prior to transplant; of the 15,931 listed in high volume center, 11,186 (70.2%) underwent transplantation, while 2,503 (15.7%) died prior to transplant. Average time on waitlist was 328.7 + 453.7 days for low-volume, 358.5+469.8 for medium-volume, and 313.7+484.6 for high-volume centers (p = NS). Cox proportional hazards analysis demonstrated listing at a higher volume center to be an independent predictor of lower death rate while on transplant waitlist (HR 0.89, P Conclusion Survival to transplantation was higher for patients listed in higher volume centers. This may be associated with higher utilization rates of LVADs which was also associated with improved waitlist outcomes, or possibly better management of advanced heart failure in centers more experienced with this patient population.

Utility of Total Cardiac and Right Ventricular Mass Ratios in Recipients with Pulmonary Hypertension: A UNOS Database Analysis

<h3>Purpose</h3> Cardiac mass ratio (CMR) is validated for donor-recipient sizing, and as a predictor of transplant outcomes. However, there is a lack of data reviewing the role CMR plays in transplant recipients with pulmonary hypertension (pHTN). In particular, the right ventricular (RV) mass ratio (RVMR) is a component of CMR not yet studied separately for this purpose. We aimed to review the relationship of CMR and RVMR with pHTN in terms of development of primary graft dysfunction (PGD) and overall survival. <h3>Methods</h3> The United Network for Organ Sharing (UNOS) database was queried for primary heart transplant patients from 1987 to 2020. Missing data was imputed using a Bayesian network. Left ventricular (LV), RV, total cardiac mass (CM), and their ratios were calculated for donors and recipients. Relevant hemodynamic variables were included in logistic regression and cox proportional-hazards models to evaluate a relationship to PGD and overall survival. A stepwise regression created parsimonious models. Covariates with statistically significant relationships to the outcomes were included in tensor product spline models. <h3>Results</h3> 62,169 patients were identified. A parsimonious logistic model for odds of PGD included RVMR (OR 0.99, p<0.001) and mean PAP (mPAP) (OR 1.00, p<0.001). A parsimonious cox model for survival included diastolic PAP (HR 1.01, p<0.001), systolic PAP (HR 1.01, p<0.001), mPAP (HR 0.98, p<0.001), transpulmonary gradient (TPG) (HR 1.01, p<0.001), and CMR (HR 0.76, p<0.001). A tensor product spline model evaluating PGD demonstrated increasing odds of PGD in patients with elevated mPAP and smaller RVMR (Figure, p<0.001). Comparable models evaluating overall survival demonstrated smaller CMR was associated with reduced survival at elevated mPAP (p<0.001) and TPG (p<0.001). <h3>Conclusion</h3> In patients with pHTN, RVMR is significantly associated with odds of developing PGD, and CMR is with overall survival. Some RV oversizing may be beneficial to mitigate the risk of PGD.

AT1R-Ab: A New Player in Pediatric Heart Transplant AMR?

<h3>Purpose</h3> Angiotensin II type 1 receptor antibodies (AT1R-Ab) are associated with non-human leukocyte antigen (HLA) mediated antibody mediated rejection (AMR) and graft failure in adult renal transplantation. They can be stimulated by ventricular assist device (VAD) support, but data regarding AT1R-Ab in pediatric heart transplantation (HT) are scarce. The purpose of this study is to describe the incidence of non-HLA mediated AMR and identification of AT1R-Ab in a pediatric HT cohort. <h3>Methods</h3> We performed a single-center retrospective review of children who underwent primary HT from July 2016 to July 2020. AMR was defined by the presence of complement deposition (+C4d) on heart biopsy. Non-HLA mediated AMR was defined by the absence of donor-specific HLA antibodies (HLA-DSA). AT1R-Ab testing was defined as < 10 negative, 10-17 borderline, and > 17 positive (ELISA). <h3>Results</h3> There were 100 patients who underwent primary HT during the study period (median age 4.5 years). There were 19 episodes of AMR in 17 patients. HLA-DSA were present in 12 episodes (63%) and absent in 7 (37%) episodes. Non-HLA mediated AMR occurred earlier post-HT compared to AMR with HLA-DSA (median 7 days vs 244 days, p = 0.04). Four patients with AMR in the absence of HLA-DSA were tested for AT1R-Ab; 3 were positive and 1 was borderline. Of the 3 patients with positive AT1R-Ab, 2 were previously supported on VAD, 2 had symptomatic AMR, 2 subsequently received losartan, and none have had recurrence of AMR (Table). <h3>Conclusion</h3> Non-HLA mediated AMR accounted for 37% of AMR episodes and occurred earlier post-HT compared to AMR with HLA-DSA in a single-center cohort. AT1R-Ab were present in 3 of 4 patients with non-HLA mediated AMR in whom AT1R-Ab testing was performed. In light of the recent data regarding AT1R-Ab in renal transplantation, investigation of the prevalence and clinical significance of AT1R-Ab in pediatric HT, particularly in early non-HLA mediated AMR and in those bridged to HT with VAD, is warranted.

Prognosis of adults with left ventricular non compaction: Results from a prospective multricentric french study

Left ventricular non compaction (LVNC) is a rare cause of cardiomyopathy related to abnormal in utero myocardial development, leading to prominent trabeculations. Its prognosis remains unclear with conflicting data and mortality ranging from 2 to 38%. The aim of this study was to define the prognosis of newly diagnosed LVNC as compared to recently diagnosed dilated cardiomyopathy (DCM). A prospective multicentric study with a 2-year follow-up was designed. The primary endpoint combined cardiovascular death, heart transplantation and hospitalisation for cardiovascular events. Three groups of patients were defined: Group A: new cases of LVNC, Group B: new cases of DCM, Group C: 1st degree LVNCs’ relatives identified as affected with LVNC. Post Hoc analysis were designed according to the 2019 DCM definition and 3 LVEF-matched subgroups were described: Group 1: LVNC with LVEF < 45%, Group 2: LVNC with LVEF > 45%, Group 3: DCM with LVEF < 45%. 94 LVNC and 67 DCM were included, with significant difference on LVEF, (43.4% vs 35.7%, P = 0.001). The post hoc analysis of the LVEF-matched subgroups showed a tendency to more frequent primary endpoint occurrence in LVNC as compared with DCM ( N = 20 [35.7%], vs. N = 10; [19.6%], respectively, P = 0.075). In the LVNC population, 28.5% of rhythmic complications, 17.8% of haemodynamic complications and 3.5% of thromboembolism were observed. We also observed a higher number of cardiovascular events by patient in LVNC as compared with DCM patients (20.7% vs. 8.5%, P = 0.087). We report the first prospective study comparing LVNC to DCM showing a tendency to an excess morbidity-mortality in the LVNC population. Our results allow to improve patient care as rhythmic disorders appear as the main complication, followed by heart failure and thromboembolism.

Criteria for Selecting Patients for Inclusion in the Waiting List for Heart Transplantation

Objective. The aim of the study was to optimize the methods of selecting patients for inclusion in the «waiting list» for heart transplantation on the basis of available international data and the introduction of selection criteria.Materials and methods. The results of the study are based on survey data and dynamic monitoring of 49 patients (median age 38 (16; 65) years; 44 men, 5 women) who were treated from 2008-2018 in the centers: Republican Scientific and Practical Center «Cardiology», Minsk, Republic of Belarus; in the Center of cardiac surgery on the basis of Hospital «Feofania». Patients were examined during the initial examination, after 3 months, 6 months and after 1 year.&#x0D; Results and discussion. The first group consisted of 24 patients with CHF who were on the waiting list for orthotopic heart transplantation, for circulatory support, median age 40.95 (18.0; 65.0) years, men - 23, women - 1; The second group consisted of 25 patients with CHF who were on the waiting list fororthotopic heart transplantation without circulatory support, median age 38.56 (17.0; 64.0) years, men - 21, women - 4.Conclusions. Scientific novelty of the obtained results. For the first time in Ukraine, a road map has been developed and implemented and the dynamics of the movement of recipients who are in the «waiting list» for heart transplantation has been analyzed. Identified risk factors that affect the long-term outcomes and quality of life of patients with heart failure III-IV functional class according to the NYHA classification. Criteria for selection of patients for primary heart transplantation have been developed and implemented. For the first time in Ukraine, a «waiting list» for a heart transplant has been formed.

Impact of implantation time on early function of cardiac transplant.

Data on out-of-ice implantation ischemia in heart transplant are scarce. We examined implantation time's impact on allograft dysfunction. We conducted a single-site retrospective review of all primary adult heart transplants from June 2012 to August 2019 for implantation warm ischemic time (WIT), defined as first atrial stitch to aortic crossclamp removal. Univariate regression was used to assess the relationship of perioperative variables to primary graft dysfunction (PGD) and to pulmonary artery pulsatility index (PAPi) at postoperative hour 24. A threshold of p < .10 was set for the inclusion of covariates in multivariate regression. Secondary analyses evaluated for consistency among alternative criteria for allograft dysfunction. A post hoc subgroup analysis examined WIT effect in prolonged total ischemia of240 min or longer. Complete data were available for 201 patients. Baseline characteristics were similar between patients who did and did not have WIT documented. In univariate analysis, female gender, longer total ischemic time (TIT), longer bypass time, greater blood transfusions, and pretransplant intensive care unit (ICU) care were associated with PGD, whereas longer bypass time was associated with worse PAPi and pretransplant ICU care was associated with better PAPi. In multivariate analysis, longer bypass time predicted PGD, and worse PAPi and preoperative ICU admission predicted PGD and better PAPi. Results did not differ in secondary or subgroup analyses. This study is one of few examining the functional impact of cardiac implantation ischemia. Results suggest allograft implantation time alone may not impact postoperative graft function, which was driven by intraoperative bypass duration and by preoperative ICU care, instead.

Abstract 15629: Optimal Metrics for Assessing Donor-recipient Size Mismatch in Pediatric Heart Transplantation: A PHTS Multi-institutional Analysis

Introduction: Traditional weight &amp; height ratios as measures of donor-recipient (D-R) matching have been challenged in adult heart transplantation (HT). The optimal metrics for D-R matching in pediatric HT remain unclear, and were evaluated in the present study. Methods: All primary pediatric HT recipients in the Pediatric Heart Transplant Society database transplanted from 1993-2019 were included. Multiple metrics of size matching - height, weight, body mass index (BMI), body surface area (BSA), predicted heart mass (PHM) and total cardiac volume (TCV) were assessed to identify the metrics that would best predict 1-year post-transplant (PTx) graft loss (death/re-transplant). Kaplan-Meier analyses (risk unadjusted) and multivariate Cox proportional hazard models (risk adjusted) were used to assess the effect of differences of various size matching metrics on survival. Results: Among 6903 D-R pairs, multivariable hazard modeling identified the following risk factors for PTx mortality: female sex, black race, bilirubin, ECMO, VAD, mechanical ventilation, ICU admission at the time of transplant, presence of congenital heart disease, early era of transplant, donor ischemic time and cardiopulmonary bypass time. After adjusting for all covariates, increasing size mismatch by height, BSA, or PHM was associated with increased 1-year PTx graft loss, with a disproportionately higher hazard for undersized donors than oversized donors (Figure). Weight, BMI and TCV were not predictive of 1-year PTx graft loss on multivariate analysis. Conclusions: In pediatric HT recipients, increasing size mismatch by height, BSA and PHM is associated with increased 1-year PTx graft loss. Undersizing donors appears to carry a higher risk than oversizing.