Does Failure to Rescue Drive Race/Ethnicity-based Disparities in Survival After Heart Transplantation?

OBJECTIVE: The objective was to assess whether race/ethnicity is an independent predictor of failure to rescue (FTR) after orthotopic heart transplantation (OHT). SUMMARY BACKGROUND DATA: Outcomes following OHT vary by patient level factors; for example, non-White patients have worse outcomes than White patients after OHT. Failure to rescue is an important factor associated with cardiac surgery outcomes, but its relationship to demographic factors is unknown. METHODS: Using the United Network for Organ Sharing database, we included all adult patients who underwent primary isolated OHT between 1/1/2006 snd 6/30/2021. FTR was defined as the inability to prevent mortality after at least one of the UNOS-designated postoperative complications. Donor, recipient, and transplant characteristics, including complications and FTR, were compared across race/ethnicity. Logistic regression models were created to identify factors associated with complications and FTR. Kaplan Meier and adjusted Cox proportional hazards models evaluated the association between race/ethnicity and posttransplant survival. RESULTS: There were 33,244 adult, isolated heart transplant recipients included: the distribution of race/ethnicity was 66% (n=21,937) White, 21.2% (7,062) Black, 8.3% (2,768) Hispanic, and 3.3% (1,096) Asian. The frequency of complications and FTR differed significantly by race/ethnicity. After adjustment, Hispanic recipients were more likely to experience FTR than White recipients (OR 1.327, 95% CI[1.075-1.639], P =0.02). Black recipients had lower 5-year survival compared with other races/ethnicities (HR 1.276, 95% CI[1.207-1.348], P <0.0001). CONCLUSIONS: In the US, Black recipients have an increased risk of mortality after OHT compared with White recipients, without associated differences in FTR. In contrast, Hispanic recipients have an increased likelihood of FTR, but no significant mortality difference compared with White recipients. These findings highlight the need for tailored approaches to addressing race/ethnicity-based health inequities in the practice of heart transplantation.

Registro español de trasplante cardiaco. XXXIV informe oficial de la Asociación de Insuficiencia Cardiaca de la Sociedad Española de Cardiología / Spanish heart transplant registry. 34th official report of the Heart Failure Association of the Spanish Society of Cardiology

Introducción y objetivos: El Registro español de trasplante cardiaco actualiza sus datos anualmente. En este artículo se presentan los datos correspondientes al año 2022.Métodos: Se describen las principales características clínicas, del tratamiento recibido y de los resultados en términos de supervivencia de los procedimientos realizados en 2022, así como las tendencias de estos desde el año 2013.Resultados: En 2022 se han realizado 311 trasplantes cardiacos (un 3,0% más que el año anterior). No se han observado cambios relevantes en las características demográficas y clínicas en 2022 respecto a los años inmediatamente anteriores, lo que confirma las tendencias ya descritas en la última década a una disminución de los procedimientos urgentes y el uso de asistencia circulatoria, sobre todo de dispositivos de asistencia ventricular. En el último decenio, las supervivencias son del 81,4 y el 73,4% a 1 año y a los 3 años, con una mejoría numérica que no ha alcanzado significación estadística.Conclusiones: En la última década se observa una estabilización en las características de los procedimientos de trasplante cardiaco y de sus resultados. Registrado en ClinicalTrial.gov (Identificador: NCT03015311).(AU)

Introduction and objectives: The Spanish heart transplant registry updates its data annually. The current update presents the data for the year 2022.Methods: We describe the main clinical characteristics, treatments received, and survival outcomes including procedures performed in 2022, along with their trends since 2013.Results: In 2022, 311 cardiac transplants were performed, representing a 3.0% increase compared with 2021. Compared with previous years, no significant changes in demographic and clinical characteristics were observed in 2022, confirming the trends identified in the last decade. These trends indicate a decrease in urgent procedures and the use of circulatory support, particularly ventricular assist devices. In the last decade, survival rates at 1 and 3 years were 81.4% and 73.4% respectively, with a slight, nonsignificant improvement.Conclusions: In the last decade, there has been a stabilization in the characteristics of heart transplant procedures and their outcomes. This trial was registered at ClinicalTrial.gov (Identifier: NCT03015311).(AU)

The impact of postoperative cognitive impairment on mid-term survival after heart transplantation.

BACKGROUND: Heart transplantation is the definitive therapy for patients with end-stage heart failure. Antecedent studies reported that a substantial proportion of heart transplant recipients developed postoperative cognitive impairment in the long term. However, no studies have explored the association between postoperative cognitive impairment and survival after heart transplantation. METHODS: The data of 43 adult patients who underwent heart transplantation were consecutively enrolled and assessed using the MMSE and MoCA neuropsychological tests. Kaplan-Meier curves and Cox proportional hazards models were used for survival analyses. Primary component analysis was performed to integrate MoCA subtests into the "Attention factor," "Naming factor," and "Orientation factor." RESULTS: About 30% of the patients were diagnosed with short-term postoperative cognitive impairment. The impairment group was older and had lower baseline cognitive performances, larger LV diameter, worse MMSE decline and higher ratio of significant MoCA decline. Postoperative cognitive impairment was significantly associated with worse survival (P = .028). Multivariate Cox analyses showed that higher postoperative MoCA score was significantly associated with lower mid-term post-transplant mortality (HR = .744 [.584, .949], P = .017), in which "Attention factor" contributed to this association most (HR = .345 [.123, .970], P = .044) rather than "Naming factor" or "Orientation factor." Notably, preoperative cognitive impairment was closely related with postoperative cognitive impairment and also indicated the worse post-transplant survival (P = .015). CONCLUSION: Postoperative as well as preoperative cognitive impairments were associated with a worse mid-term survival after heart transplantation, indicating that neuropsychological assessments before and after heart transplantation should be routinely performed for heart transplant recipients for better risk stratification.

Hemodynamic markers of pulmonary vasculopathy for prediction of early right heart failure and mortality after heart transplantation.

BACKGROUND: Elevated pulmonary vascular resistance (PVR) is broadly accepted as an imminent risk factor for mortality after heart transplantation (HTx). However, no current HTx recipient risk score includes PVR or other hemodynamic parameters. This study examined the utility of various hemodynamic parameters for risk stratification in a contemporary HTx population. METHODS: Patients from seven German HTx centers undergoing HTx between 2011 and 2015 were included retrospectively. Established risk factors and complete hemodynamic datasets before HTx were analyzed. Outcome measures were overall all-cause mortality, 12-month mortality, and right heart failure (RHF) after HTx. RESULTS: The final analysis included 333 patients (28% female) with a median age of 54 (IQR 46-60) years. The median mean pulmonary artery pressure was 30 (IQR 23-38) mm Hg, transpulmonary gradient 8 (IQR 5-10) mm Hg, and PVR 2.1 (IQR 1.5-2.9) Wood units. Overall mortality was 35.7%, 12-month mortality was 23.7%, and the incidence of early RHF was 22.8%, which was significantly associated with overall mortality (log-rank HR 4.11, 95% CI 2.47-6.84; log-rank p < .0001). Pulmonary arterial elastance (Ea) was associated with overall mortality (HR 1.74, 95% CI 1.25-2.30; p < .001) independent of other non-hemodynamic risk factors. Ea values below a calculated cutoff represented a significantly reduced mortality risk (HR 0.38, 95% CI 0.19-0.76; p < .0001). PVR with the established cutoff of 3.0 WU was not significant. Ea was also significantly associated with 12-month mortality and RHF. CONCLUSIONS: Ea showed a strong impact on post-transplant mortality and RHF and should become part of the routine hemodynamic evaluation in HTx candidates.

Association of Donors With US Public Health Service Risk Criteria and Outcomes After Adult vs Pediatric Cardiac Transplant.

Importance: The United Network for Organ Sharing (UNOS) evaluates donor risk for acute transmission of HIV, hepatitis B, or hepatitis C based on US Public Health Services (PHS)-specific criteria. However, recent data regarding use and outcomes of those donors with PHS risk criteria among pediatric and adult heart transplant recipients are lacking. Objective: To compare use and outcomes of graft from donors with PHS risk criteria vs those with a standard-risk donor (SRD) in children vs adults in a contemporary cohort. Design, Setting, and Participants: This cohort was a nationwide analysis of heart transplants in the US that used data from the UNOS database. Participants were children (<18 years old) and adults (≥18 years old) who received a heart transplant from January 1, 2010, to December 31, 2021. Exposures: UNOS-defined donor risk status. Main Outcomes and Measures: Trend analysis compared changes in PHS risk criteria use among children and adults. Patient survival was analyzed using Kaplan-Meier curves with log rank and Cox proportional hazards to compare PHS risk-criteria outcomes vs SRD-criteria outcomes in children and adult heart transplant recipients. Additional analysis was performed among adults who received a PHS-risk criteria graft that was previously declined for pediatric recipients. Results: Of 5115 pediatric transplant recipients (donor without PHS risk median [IQR] age, 5 [0-13] years and donor with PHS risk median [IQR] age, 8 [0-14] years) and 30 289 adult heart transplant recipients (donor without PHS risk median [IQR] age, 56 [46-63] years and donor with PHS risk median [IQR] age, 57 [47-63] years), PHS risk criteria comprised 8% in children vs 25% in adults. PHS criteria are being increasingly used over the past decade with the proportion of recipients transplanted with PHS risk-criteria donors being approximately 3 times greater among adult recipients than children recipients. Pediatric recipients of a PHS risk-criteria donor had greater pretransplant ventilatory support, whereas adult recipients of a PHS risk-criteria donor had greater pretransplant extracorporeal membrane oxygenation use. Patient survival was similar between pediatric recipients of PHS risk-criteria grafts vs SRD-criteria grafts and slightly higher among adult recipients of PHS risk-criteria grafts vs SRD-criteria grafts. The 1778 adult recipients who received a PHS criteria-risk donor that was previously declined for pediatric recipients had similar patient survival recipients compared with SRD-criteria donors (HR, 0.92; 95% CI, 0.81-1.03; P = .18). Conclusions and Relevance: In the current era, a 3-fold greater proportion of adult recipients receive a PHS risk-criteria graft compared with children despite similar posttransplant patient survival. The ongoing organ donor shortage underscores the need for consideration of PHS risk criteria where these donors remain underused.

Association of COVID-19 Vaccination With Risk of COVID-19 Infection, Hospitalization, and Death in Heart Transplant Recipients.

Importance: Orthotopic heart transplant (OHT) recipients are at increased risk for morbidity and mortality after SARS-CoV-2 infection. Although antibody response to COVID-19 vaccination is lower in solid organ transplant recipients, there has been no study assessing the safety and effectiveness of COVID-19 vaccination in OHT recipients. Objective: To assess the safety and effectiveness of COVID-19 vaccination and associations with SARS-CoV-2 infection and clinical outcomes in a large population of adult OHT recipients. Design, Setting, and Participants: This case-control study examined data from a US heart transplant program at a single center for all adult recipients of OHT who were followed up from January 15, 2021, through January 31, 2022. Main Outcomes and Measures: The primary outcome was number of SARS-CoV-2 infections and related hospitalizations, intensive care unit (ICU) admissions, and deaths between vaccinated vs unvaccinated adult recipients of OHT. Results: A total of 436 patients who received OHT were included in the study, of which 106 patients were infected with COVID-19. The mean (SD) age was 54 (17) years; 303 (69.5%) were men and 133 (30.5%) were women. There were 366 patients in the vaccinated cohort with 72 COVID-19 infections (19.7%), 15 hospitalizations (4.1%), 4 ICU admissions (1.1%), and 3 deaths (0.8%). There were 70 patients in the unvaccinated cohort with 34 COVID-19 infections (48.6%), 10 hospitalizations (14.3%), 3 ICU admissions (4.3%), and 3 deaths (4.3%). COVID-19 vaccination was associated with a lower risk of COVID-19 infection (risk ratio [RR], 0.41; 95% CI, 0.30-0.56), hospitalization (RR, 0.29; 95% CI, 0.14-0.61), and death (RR, 0.19; 95% CI, 0.05-0.82). Among the 366 vaccinated OHT recipients, there was no echocardiographic evidence of graft dysfunction, clinically significant rejection, or allosensitization at 6 months after they received the COVID-19 vaccine. Conclusions and Relevance: Patients with OHT who are infected with SARS-CoV-2 are at greater risk of severe infection and death compared with immunocompetent individuals. COVID-19 vaccination was associated with fewer COVID-19 infections, hospitalizations, and deaths, with no heart transplant-specific adverse events. COVID-19 vaccination for all OHT recipients is of paramount importance.

Combined heart and liver transplantation: an updated systematic review.

INTRODUCTION: Combined heart and liver transplantation (CHLT) is one of the most complex procedures of surgery that has been implemented in the last 35 years. The aim of our meta-analysis was to investigate the safety and efficacy of CHLT. MATERIALS: The meta-analysis was designed according to PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) and AMSTAR (A MeaSurement Tool to Assess systematic Reviews) recommendations. A literature search was conducted up to April 2020 using the MEDLINE,® SCOPUS,® ClinicalTrials.gov, Embase™, Cochrane Central Register of Controlled Trials and Google Scholar™ databases. RESULTS: Our meta-analysis included 16 studies with 860 patients. The mortality rate following CHLT was 14.1%. One and five-year survival rates were 85.3% and 71.4% while the heart and liver rejection rates were 6.1% and 9.1% respectively. The hospital stay was 25.8 days and the intensive care unit stay was 9.9 days. Pooled values were also calculated for cardiopulmonary bypass duration, units of transfused red blood cells and fresh frozen plasma, postoperative infection rate, mechanical ventilation rate and follow-up duration. CONCLUSIONS: Despite its complexity, CHLT is a safe and effective procedure for the management of lethal diseases that lead to progressive heart and/or liver failure. Nevertheless, there must be strict adherence to the indications for surgery, and future studies should compare CHLT with isolated cardiac and hepatic transplantations.

Effect of Moderate Hypothermia vs Normothermia on 30-Day Mortality in Patients With Cardiogenic Shock Receiving Venoarterial Extracorporeal Membrane Oxygenation: A Randomized Clinical Trial.

IMPORTANCE: The optimal approach to the use of venoarterial extracorporeal membrane oxygenation (ECMO) during cardiogenic shock is uncertain. OBJECTIVE: To determine whether early use of moderate hypothermia (33-34 °C) compared with strict normothermia (36-37 °C) improves mortality in patients with cardiogenic shock receiving venoarterial ECMO. DESIGN, SETTING, AND PARTICIPANTS: Randomized clinical trial of patients (who were eligible if they had been endotracheally intubated and were receiving venoarterial ECMO for cardiogenic shock for <6 hours) conducted in the intensive care units at 20 French cardiac shock care centers between October 2016 and July 2019. Of 786 eligible patients, 374 were randomized. Final follow-up occurred in November 2019. INTERVENTIONS: Early moderate hypothermia (33-34 °C; n = 168) for 24 hours or strict normothermia (36-37 °C; n = 166). MAIN OUTCOMES AND MEASURES: The primary outcome was mortality at 30 days. There were 31 secondary outcomes including mortality at days 7, 60, and 180; a composite outcome of death, heart transplant, escalation to left ventricular assist device implantation, or stroke at days 30, 60, and 180; and days without requiring a ventilator or kidney replacement therapy at days 30, 60, and 180. Adverse events included rates of severe bleeding, sepsis, and number of units of packed red blood cells transfused during venoarterial ECMO. RESULTS: Among the 374 patients who were randomized, 334 completed the trial (mean age, 58 [SD, 12] years; 24% women) and were included in the primary analysis. At 30 days, 71 patients (42%) in the moderate hypothermia group had died vs 84 patients (51%) in the normothermia group (adjusted odds ratio, 0.71 [95% CI, 0.45 to 1.13], P = .15; risk difference, -8.3% [95% CI, -16.3% to -0.3%]). For the composite outcome of death, heart transplant, escalation to left ventricular assist device implantation, or stroke at day 30, the adjusted odds ratio was 0.61 (95% CI, 0.39 to 0.96; P = .03) for the moderate hypothermia group compared with the normothermia group and the risk difference was -11.5% (95% CI, -23.2% to 0.2%). Of the 31 secondary outcomes, 30 were inconclusive. The incidence of moderate or severe bleeding was 41% in the moderate hypothermia group vs 42% in the normothermia group. The incidence of infections was 52% in both groups. The incidence of bacteremia was 20% in the moderate hypothermia group vs 30% in the normothermia group. CONCLUSIONS AND RELEVANCE: In this randomized clinical trial involving patients with refractory cardiogenic shock treated with venoarterial ECMO, early application of moderate hypothermia for 24 hours did not significantly increase survival compared with normothermia. However, because the 95% CI was wide and included a potentially important effect size, these findings should be considered inconclusive. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02754193.

Trends in Survival for Pediatric Transplantation.

OBJECTIVES: Progress in pediatric transplantation measured in the context of waitlist and posttransplant survival is well documented but falls short of providing a complete perspective for children and their families. An intent-to-treat analysis, in which we measure survival from listing to death regardless of whether a transplant is received, provides a more comprehensive perspective through which progress can be examined. METHODS: Univariable and multivariable Cox regression was used to analyze factors impacting intent-to-treat survival in 12 984 children listed for heart transplant, 17 519 children listed for liver transplant, and 16 699 children listed for kidney transplant. The Kaplan-Meier method and log-rank test were used to assess change in waitlist, posttransplant, and intent-to-treat survival. Wait times and transplant rates were compared by using χ2 tests. RESULTS: Intent-to-treat survival steadily improved from 1987 to 2017 in children listed for heart (hazard ratio [HR] 0.96, 95% confidence interval [CI] 0.96-0.97), liver (HR 0.95, 95% CI 0.94-0.97), and kidney (HR 0.97, 95% CI 0.95-0.99) transplant. Waitlist and posttransplant survival also improved steadily for all 3 organs. For heart transplant, the percentage of patients transplanted within 1 year significantly increased from 1987 to 2017 (60.8% vs 68.7%); however, no significant increase was observed in liver (68.9% vs 72.5%) or kidney (59.2% vs 62.7%) transplant. CONCLUSIONS: Intent-to-treat survival, which is more representative of the patient perspective than individual metrics alone, steadily improved for heart, liver, and kidney transplant over the study period. Further efforts to maximize the donor pool, improve posttransplant outcomes, and optimize patient care while on the waitlist may contribute to future progress.

Circumstances surrounding end-of-life in pediatric patients pre- and post-heart transplant: a report from the Pediatric Heart Transplant Society.

BACKGROUND: Although mortality has decreased considerably in pediatric heart transplantation, waitlist and post-transplant death rates remain notable. End-of-life focused research in this population, however, is very limited. This Pediatric Heart Transplant Society study aimed to describe the circumstances surrounding death of pediatric heart transplant patients. METHODS: A retrospective analysis of the multi-institutional, international, Pediatric Heart Transplant Society registry was conducted. Descriptive statistics and univariate analyses were performed to 1) describe end-of-life in pediatric pre- and post-heart transplant patients and 2) examine associations between location of death and technological interventions at end-of-life with demographic and disease factors. RESULTS: Of 9217 patients (0-18 years) enrolled in the registry between 1993 and 2018, 2804 (30%) deaths occurred; 1310 while awaiting heart transplant and 1494 post-heart transplant. The majority of waitlist deaths (89%) occurred in the hospital, primarily in ICU (74%) with most receiving mechanical ventilation (77%). Fewer post-transplant deaths occurred in the hospital (22%). Out-of-hospital death was associated with older patient age (p < .01). CONCLUSIONS: ICU deaths with high use of technological interventions at end-of-life were common, particularly in patients awaiting heart transplant. In this high mortality population, findings raise challenging considerations for clinicians, families, and policy makers on how to balance quality of life amidst high risk for hospital-based death.

Venoarterial extracorporeal membrane oxygenation is a viable option as a bridge to heart transplant.

OBJECTIVE: Venoarterial extracorporeal membrane oxygenation is a rescue therapy for patients in cardiogenic shock. We hypothesize that patients bridged to heart transplant with extracorporeal membrane oxygenation have decreased survival. METHODS: The United Network of Organ Sharing database was retrospectively reviewed from January 1, 1999, to March 31, 2018, for heart transplant recipients. Recipients bridged with any form of mechanical support and those without support were compared with recipients bridged with extracorporeal membrane oxygenation. The primary end point was restricted mean survival time through 16.7 years. RESULTS: Of 26,918 recipients, 15,076 required no pretransplant mechanical support (56.0%). Support patients included 9321 with left ventricular assist devices (34.6%), 53 with right ventricular assist devices (0.2%), 258 with total artificial hearts (1.0%), 686 with biventricular assist devices (2.6%), 1378 with intra-aortic balloon pumps (5.1%), and 146 who required extracorporeal membrane oxygenation (0.5%). In the first 16.7 years post-transplant, compared with recipients bridged with extracorporeal membrane oxygenation, estimated adjusted restricted mean survival time was higher in patients who required no mechanical support (16.6 months [14.0-19.4]) and patients with a left ventricular assist device (16.5 months [99% confidence interval, 13.9-19.2]), an intra-aortic balloon pump (11.2 months [8.3-14.7]), or a biventricular assist device (6.6 months [3.6-10.3]). Restricted mean survival time in patients with a right ventricular assist device or a total artificial heart was similar to patients with extracorporeal membrane oxygenation. CONCLUSIONS: Recipients bridged with extracorporeal membrane oxygenation were estimated to survive 16.6 months less than nonmechanical circulatory support recipients. Bridge to heart transplant with extracorporeal membrane oxygenation is a viable option, and these patients should be considered transplant candidates.

Outcomes after heart retransplantation: A 50-year single-center experience.

OBJECTIVES: To evaluate outcomes after heart retransplantation. METHODS: From January 6, 1968, to June 2019, 123 patients (112 adult and 11 pediatric patients) underwent heart retransplantation, and 2092 received primary transplantation at our institution. Propensity-score matching was used to account for baseline differences between the retransplantation and the primary transplantation-only groups. Kaplan-Meier survival analyses were performed. The primary end point was all-cause mortality, and secondary end points were postoperative complications. RESULTS: Retransplantation recipient age was 39.6 ± 16.4 years, and donor age was 26.4 ± 11.2 years. Ninety-two recipients (74.8%) were male. Compared with recipients who only underwent primary heart transplantation, retransplantation recipients were more likely to have hypertension (44/73.3% vs 774/53.3%, P = .0022), hyperlipidemia (40/66.7% vs 447/30.7%, P < .0001), and require dialysis (7/11.7% vs 42/2.9%, P = .0025). The indications for heart retransplantation were cardiac allograft vasculopathy (32/80%), primary graft dysfunction (6/15%), and refractory acute rejection (2/5%). After matching, postoperative outcomes such as hospital length of stay, severe primary graft dysfunction requiring intra-aortic balloon pump or extracorporeal membrane oxygenation, cerebral vascular accident, respiratory failure, renal failure requiring dialysis, and infection were similar between the 2 groups. Matched median survival after retransplantation was 4.6 years compared with 6.5 years after primary heart transplantation (log-rank P = .36, stratified log-rank P = .0063). CONCLUSIONS: In this single-center cohort, the unadjusted long-term survival after heart retransplantation was inferior to that after primary heart transplantation, and short-term survival difference persisted after propensity-score matching. Heart retransplantation should be considered for select patients for optimal donor organ usage.

Factors associated with mortality or transplantation versus Fontan completion after cavopulmonary shunt for patients with tricuspid atresia.

OBJECTIVE: Tricuspid atresia with normally related great vessels (TA) is considered the optimal substrate for the Fontan pathway. The factors associated with death or transplantation after cavopulmonary shunt (CPS) are underappreciated. We aimed to determine factors associated with CPS-Fontan interstage death/transplantation versus transition to Fontan in TA. METHODS: A total of 417 infants younger than 3 months of age with TA were enrolled (January 1999 to February 2020) from 40 institutions into the Congenital Heart Surgeons' Society TA cohort. Parametric competing risk methodology was used to determine factors associated with the competing end points of death/transplantation without Fontan completion, and transition to Fontan. RESULTS: CPS was performed in 382 patients with TA; of those, 5% died or underwent transplantation without transition to Fontan and 91% transitioned to Fontan by 5 years after CPS. Prenatal diagnosis (hazard ratio [HR], 0.74; P < .001) and pulmonary artery band (PAB) at CPS (HR, 0.50; P < .001) were negatively associated with Fontan completion. Preoperative moderate or greater mitral valve regurgitation (HR, 3.0; P < .001), concomitant mitral valve repair (HR, 11.0; P < .001), PAB at CPS (HR, 3.0; P < .001), postoperative superior vena cava interventions (HR, 9.0; P < .001), and CPS takedown (HR, 40.0; P < .001) were associated with death/transplantation. CONCLUSIONS: The mortality rate after CPS in patients with TA is notable. Those with preoperative mitral valve regurgitation remain a high-risk group. PAB at the time of CPS being associated with both increased risk of death and decreased Fontan completion may represent a deleterious effect of antegrade pulmonary blood flow in the CPS circulation.

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.

Hepatorenal dysfunction assessment with the Model for End-Stage Liver Disease Excluding INR score predicts worse survival after heart transplant in pediatric Fontan patients.

BACKGROUND: Fontan physiology results in multiorgan dysfunction, most notably affecting the liver and kidney. We evaluated the utility of Model for End-Stage Liver Disease Excluding INR (MELD-XI) score, a score evaluating the function of both liver and kidney to identify Fontan patients at increased risk for morbidity and mortality post-heart transplant. METHODS: The Pediatric Heart Transplant Society database was queried to identify Fontan patients listed for heart transplant between January 2005 and December 2018. MELD-XI scores were calculated at listing and heart transplant. A multivariable analysis was conducted to identify risk factors for post-heart transplant mortality. Demographic, clinical characteristics, and survival differences were evaluated and compared between the high and low MELD-XI score cohorts. The impact of changing MELD-XI scores during the waitlist period on post-heart transplant outcomes was also evaluated. RESULTS: Of 565 Fontan patients who underwent transplantation, 524 (93%) had calculable MELD-XI scores at the time of heart transplant: 421 calculable at listing and 392 calculable at listing and at heart transplant. On multivariable analysis, only MELD-XI score (squared) (hazard ratio, 1.007), history of protein-losing enteropathy (hazard ratio, 2.1), and ventricular assist device use at transplant (hazard ratio, 3.4) were risk factors for early phase post-heart transplant mortality. Patients with high MELD-XI scores at heart transplant had inferior survival post-heart transplant (P = .02); those in the high MELD-XI score cohort at wait listing and heart transplant tend to have the worst post-heart transplant survival; however, this was not significant (P = .42). CONCLUSIONS: The MELD-XI, an easily calculated score, serves as a valuable aid in identifying pediatric Fontan patients at increased risk for post-heart transplant mortality.

Simultaneous pediatric heart-kidney transplant outcomes in the US: A-25 year National Cohort Study.

BACKGROUND: Pediatric sHKTx remains uncommon in the US. We examined outcomes of pediatric sHKTx compared to PHTx alone. Our objective was to identify a threshold eGFR that justified pediatric sHKTx. METHODS: Data from the SRTR heart and kidney databases were used to identify 9245 PHTx, and 63 pediatric sHKTx performed between 1992 and 2017 (age ≤21 years). RESULTS: The median age for sHKTx was 16 years, and included 31 males (31/63 = 49%). Over half of sHKTx (36/63 = 57%) were performed in cases where pretransplant dialysis was initiated. Among patients who required pretransplant dialysis, the risk of death in sHKTx recipients was significantly lower than PHTx alone (sHKTx vs. PHTx: HR 0.4, 95% CI [0.2, 0.9], p = .01). In those without pretransplant dialysis, there was no improvement in survival between sHKTx and PHTx (p = .2). When stratified by eGFR, PHTx alone recipients had worse survival than sHKTx in the group with eGFR ≤35 ml/min/1.73 m2 (p = .04). The 1- and 5-year actuarial survival rates in pediatric sHKTx recipients were 87% and 81.5% respectively and was similar to isolated PHTx (p = .5). One-year rates of treated heart (11%) and kidney (7.9%) rejection were similar in sHKTx compared to PHTx alone (p = .7) and pediatric kidney transplant alone (p = .5) respectively. CONCLUSION: Pediatric sHKTx should be considered in HTx candidates with kidney failure requiring dialysis or eGFR ≤35 ml/min/1.73 m2 . The utility of sHKTx in cases of kidney failure not requiring dialysis warrants further study.

Overexpression of PD-1 on T cells promotes tolerance in cardiac transplantation via ICOS-dependent mechanisms.

The programmed death 1/programmed death ligand 1 (PD-1/PD-L1) pathway is a potent inhibitory pathway involved in immune regulation and is a potential therapeutic target in transplantation. In this study, we show that overexpression of PD-1 on T cells (PD-1 Tg) promotes allograft tolerance in a fully MHC-mismatched cardiac transplant model when combined with costimulation blockade with CTLA-4-Ig. PD-1 overexpression on T cells also protected against chronic rejection in a single MHC II-mismatched cardiac transplant model, whereas the overexpression still allowed the generation of an effective immune response against an influenza A virus. Notably, Tregs from PD-1 Tg mice were required for tolerance induction and presented greater ICOS expression than those from WT mice. The survival benefit of PD-1 Tg recipients required ICOS signaling and donor PD-L1 expression. These results indicate that modulation of PD-1 expression, in combination with a costimulation blockade, is a promising therapeutic target to promote transplant tolerance.

Changing Demographics, Temporal Trends in Waitlist, and Posttransplant Outcomes After Heart Transplantation in the United States: Analysis of the UNOS Database 1991-2019.

BACKGROUND: We sought to investigate temporal trends in patient characteristics, waitlist, and posttransplant outcomes after heart transplantation in the United States. METHODS: Using data from the United Network of Organ Sharing, we identified adults listed for heart transplantation between 1991 and 2019. Patients were divided into 4 eras based on the 3 time points in which changes were made to the patient selection/allocation policy (Era 1=January 1991-January 1999; Era 2=January 1999-July 2006; Era 3=July 2006-October 2018; and Era 4=October 2018-March 2020), and patient characteristics, waitlist, and posttransplant outcomes were evaluated for each era. RESULTS: Between 1991 and 2019, 95 179 patients were added to the heart transplantation waitlist. Compared with Era 1, patients listed in Era 4 were older (mean age: 50 versus 52 years) and with higher risk comorbidities (eg, 10% versus 28.8% diabetes, 23.3% versus 35.6% obese). Over the study period, 22 738 patients died or were permanently delisted for deterioration on the waitlist while 61 687 were transplanted. Compared with the preceding era, there was significant decrease in death or deterioration in the last 2 eras (sub-hazard ratio, 0.67 [95% CI, 0.65-0.70] for Era 3 versus Era 2 and sub-hazard ratio, 0.65 [95% CI, 0.58-0.73] for Era 4 versus 3). Across the years, 27.1% to 40.5% of those on the waitlist were transplanted. Among those transplanted, there was increase in the rates of in-hospital stroke (2.8% in Era 1 to 3.7% in Era 4), renal failure requiring dialysis (7.2%-17.1%), and length-of-stay (14-17days), P<0.001. However, this did not negatively impact short-term survival when compared with the preceding era (1-year graft survival from Era 1 to Era 4=84.1%, 86.4%, 90.4%, and 89.7%, respectively). CONCLUSIONS: There have been significant changes in the characteristics of patients listed for heart transplantation. Although transplant volume has increased, the wide supply-demand gap persisted. The last two changes in the allocation policy achieved their primary objective of reducing waitlist mortality.