Improved survival in pediatric heart transplant recipients: have white, black and Hispanic children benefited equally?

Improvement in patient selection, management and outcomes in infant heart transplant from 2000 to 2020

OBJECTIVES

The study's primary outcome was to evaluate if post-transplant survival has improved over the last 2 decades. Secondary outcomes were the infant's waitlist mortality, waitlist time and identifying factors that affected the infant's survival.

METHODS

United Network for Organ Sharing (UNOS) database was queried for infants (age ≤ 1) who were listed for heart transplantation between 2000 and 2020. The years were divided into 3 eras (Era 1 2000-2006, Era 2 2007-2013 and Era 3 2014-2020). Non-parametric tests, Chi-Squared, Log-Rank test and Cox-Proportional hazard ratio were used for analysis (α = 0.05).

RESULTS

4234 infants were listed for heart transplants between 2000 and 2020. At the time of listing, Infants in era 3 were more likely to be heavier [in kg (P < 0.001)] and had better renal function (P < 0.001). Additionally, they were less likely to be on dialysis (P < 0.001), on a ventilator (P < 0.001) and on extracorporeal membrane oxygenation (P < 0.001). There has been a significant increase in left ventricular assist device use (P < 0.001), though there was no difference in waitlist (0.154) or post-transplant survival (0.51). In all 3 eras, waitlist survival (P < 0.001) and post-transplant survival (P < 0.001) have improved significantly. Congenital heart disease and extracorporeal membrane oxygenation were associated with worse waitlist survival in all 3 eras (P < 0.05). Infants are now waiting longer on the waitlist (in days) (33 Era 1 vs 46 Era 2 vs 67 Era 3, P < 0.001).

CONCLUSIONS

Infant heart transplant outcomes have improved, but they are now waiting longer on the waitlist. Further improvement in increasing the donor pool, expert consensus on listing strategies and donor utilization is needed to improve outcomes.

Lower opportunity ZIP code is associated with worse outcomes after listing in pediatric heart transplantation

BACKGROUND

The Child Opportunity Index (COI) comprehensively measures children's social determinants of health. We describe association between COI and outcomes after listing for heart transplantation.

METHODS

We conducted a retrospective review of the United Network for Organ Sharing (UNOS) database for U.S. children listed for heart transplant between 2012 and 2020. ZIP codes were utilized to assign COI. Primary outcome was survival from time of listing. Secondary outcomes included waitlist survival, 1-year post-transplant survival, and conditional 1-year post-transplant survival. Cox regression was performed adjusting for payor, age, race, diagnosis, and support at listing for all outcomes except waitlist survival, for which Fine-Gray competing risk analysis was performed.

RESULTS

Of 5,723 children listed, 109 were excluded due to missing ZIP codes. Race/ethnicity and payor were associated with COI (p < 0.001). Patients living in very low COI ZIP codes compared to all others had increased mortality from time of listing (HR 1.16, CI 1.03-1.32, p = 0.02) with 1-, 5-, and 9-year survival of 79.3% vs 82.2%, 66.5% vs 73.0%, and 53.6% vs 64.7% respectively, were more likely to be removed from the waitlist due to death or being too sick (subdistribution HR 1.26, 95% CI 1.10-1.42), and had increased mortality conditional on one-year post-transplant survival (HR 1.38, 1.09-1.74, p = 0.008) with 1-, 3-, and 5- year survival of 94.7% vs 97.3%, 87.0% vs 93.1%, and 78.6% vs 86.9%.

CONCLUSIONS

Children living in lower opportunity ZIP codes had poorer survival from time of listing, poorer waitlist survival, and poorer conditional one-year post-transplant survival.

Review on clinician bias and its impact on racial and socioeconomic disparities in pediatric heart transplantation

This expert review seeks to highlight implicit bias in health care, transplant medicine, and pediatric heart transplantation to focus attention on the role these biases may play in the racial/ethnic and socioeconomic disparities noted in pediatric heart transplantation. This review breaks down the transplant decision making process to highlight points at which implicit bias may affect outcomes and discuss how the science of human decision making may help understand these complex processes.

Racial disparity exists in the utilization and post-transplant survival benefit of ventricular assist device support in children

PURPOSE

Children of minority race and ethnicity experience inferior outcomes postheart transplantation (HTx). Studies have associated ventricular assist device (VAD) bridge-to-transplant (BTT) with similar-to-superior post-transplant-survival (PTS) compared to no mechanical circulatory support. It is unclear whether racial and ethnic discrepancies exist in VAD utilization and outcomes.

METHODS

The United Network for Organ Sharing (UNOS) database was used to identify 6,121 children (<18 years) listed for HTx between 2006 and 2021: black (B-22% of cohort), Hispanic (H-21%), and white (W-57%). VAD utilization, outcomes, and PTS were compared between race/ethnicity groups. Multivariable Cox proportional analyses were used to study the association of race and ethnicity on PTS with VAD BTT, using backward selection for covariates.

RESULTS

Black children were most ill at listing, with greater proportions of UNOS status 1A/1 (p < 0.001 vs H & W), severe functional limitation (p < 0.001 vs H & W), and greater inotrope requirements (p < 0.05 vs H). Non-white children had higher proportions of public insurance. VAD utilization at listing was: B-11%, H-8%, W-8% (p = 0.001 for B vs H & W). VAD at transplant was: B-24%, H-21%, W-19% (p = 0.001 for B vs H). At transplant, all VAD patients had comparable clinical status (functional limitation, renal/hepatic dysfunction, inotropes, mechanical ventilation; all p > 0.05 between groups). Following VAD, hospital outcomes and one-year PTS were equivalent but long-term PTS was significantly worse among non-whites-(p < 0.01 for W vs B & H). On multivariable analysis, black race independently predicted mortality (hazard ratio 1.67 [95% confidence interval 1.22-2.28]) while white race was protective (0.54 [0.40-0.74]).

CONCLUSIONS

Pediatric VAD use is, seemingly, equitable; the most ill patients receive the most VADs. Despite similar pretransplant and early post-transplant benefits, non-white children experience inferior overall PTS after VAD BTT.

Racial disparities in post-transplant stroke and mortality following stroke in adult cardiac transplant recipients in the United States

Black heart transplant recipients have a higher mortality rate than white recipients 6-12 months after transplant. Whether there are racial disparities in post-transplant stroke incidence and all-cause mortality following post-transplant stroke among cardiac transplant recipients is unknown. Using a nationwide transplant registry, we assessed the association between race and incident post-transplant stroke using logistic regression and the association between race and mortality among adults who survived a post-transplant stroke using Cox proportional hazards regression. We found no evidence of an association between race and the odds of post-transplant stroke (OR = 1.00, 95% CI: 0.83-1.20). The median survival time of those with a post-transplant stroke in this cohort was 4.1 years (95% CI: 3.0, 5.4). There were 726 deaths among the 1139 patients with post-transplant stroke, including 127 deaths among 203 Black patients and 599 deaths among 936 white patients. Among post-transplant stroke survivors, Black transplant recipients experienced a 23% higher rate of mortality compared to white recipients (HR = 1.23, 95% CI: 1.00-1.52). This disparity is strongest in the period beyond the first 6 months and appears to be mediated by differences in the post-transplant setting of care between Black and white patients. The racial disparity in mortality outcomes was not evident in the past decade. The improved survival of Black patients in the recent decade may reflect overall protocol improvements for heart transplant recipients irrespective of race, such as advancements in surgical techniques and immediate postoperative care as well as increased awareness about reducing racial disparities.

A systematic review of social determinants of health in pediatric organ transplant outcomes

BACKGROUND

Equitable access to pediatric organ transplantation is critical, although risk factors negatively impacting pre- and post-transplant outcomes remain. No synthesis of the literature on SDoH within the pediatric organ transplant population has been conducted; thus, the current systematic review summarizes findings to date assessing SDoH in the evaluation, listing, and post-transplant periods.

METHODS

Literature searches were conducted in Web of Science, Embase, PubMed, and Cumulative Index to Nursing and Allied Health Literature databases.

RESULTS

Ninety-three studies were included based on pre-established criteria and were reviewed for main findings and study quality. Findings consistently demonstrated disparities in key transplant outcomes based on racial or ethnic identity, including timing and likelihood of transplant, and rates of rejection, graft failure, and mortality. Although less frequently assessed, variations in outcomes based on geography were also noted, while findings related to insurance or SES were inconsistent.

CONCLUSION

This review underscores the persistence of SDoH and disparity in equitable transplant outcomes and discusses the importance of individual and systems-level change to reduce such disparities.

Children from socioeconomically disadvantaged communities present in more advanced heart failure at the time of transplant listing

Transplant registries in the US do not collect information about community level risk factors. We utilized a community level socio-economic risk indicator, the distressed communities' index to understand its association with clinical presentation among children listed for heart transplant (HT). We found that currently, majority (40%) of children listed from distressed communities are Black. On multivariable analysis, compared to children from prosperous communities, those from distressed communities listed for HT were significantly more likely to be Status 1A (adjusted odds ratio [aOR] 1.39) and on a ventricular assist device (aOR 1.44). Compared to White children from prosperous communities, both Black and White children from distressed communities were more likely to be listed Status 1A (aOR 2.1 and 1.36 respectively) and have renal dysfunction (aOR 1.71 and 1.52 respectively). In conclusion, heart failure severity at listing appears more likely associated with community-level risk factors and less so with child's race/ethnicity.

Racial and socioeconomic disparities in pediatric heart transplant outcomes in the era of anti-thymocyte globulin induction

BACKGROUND

Black race is associated with worse outcomes across solid organ transplantation. Augmenting immunosuppression through antithymocyte globulin (ATG) induction may mitigate organ rejection and graft loss. We investigated whether racial and socioeconomic outcome disparities persist in children receiving ATG induction.

METHODS

Using the Pediatric Heart Transplant Society registry, we compared outcomes in Black and White children who underwent heart transplant with ATG induction between 2000 and 2020. The primary outcomes of treated rejection, rejection with hemodynamic compromise (HC), and graft loss (death or re-transplant). We explored the association of these outcomes with race and socioeconomic disparity, assessed using a neighborhood deprivation index [NDI] score at 1-year post-transplant (high NDI score implies more socioeconomic disadvantage).

RESULTS

The study cohort included 1,719 ATG-induced pediatric heart transplant recipients (22% Black, 78% White). There was no difference in first year treated rejection (Black 24.5%, White 28.1%, p = 0.2). During 10 year follow up, the risk of treated rejection was similar; however, Black recipients were at higher risk of HC rejection (p = 0.009) and graft loss (p = 0.02). Black recipients had a higher mean NDI score (p < 0.001). Graft loss conditional on 1-year survival was associated with high NDI score in both White and Black recipients (p < 0.0001). In a multivariable Cox model, both high NDI score (HR 1.97, 95% CI 1.23-3.17) and Black race (HR 2.22, 95% CI 1.40-3.53) were associated with graft loss.

CONCLUSION

Black race and socioeconomic disadvantage remain associated with late HC rejection and graft loss in children with ATG induction. These disparities represent important opportunities to improve long term transplant outcomes.

Racial and Ethnic Disparities in Incidence and Prognosis of Perioperative Stroke Among Pediatric Cardiac Transplant Recipients

Background

In the general population, Black children have a higher incidence of stroke and all‐cause mortality after stroke than White children. Beginning 6 months following cardiac transplantation, Black children have higher mortality than White children. However, whether there are racial and ethnic disparities in incidence and all‐cause mortality following perioperative stroke among pediatric cardiac transplant recipients is unknown.

Methods and Results

Using the Scientific Registry of Transplant Recipients, we studied children who underwent their first heart transplant in the United States between January 1994 and September 2019. Using multivariable logistic regression, we assessed the association between race and ethnicity and perioperative stroke. We used multivariable piecewise Cox regression to examine the association between race and ethnicity and mortality among survivors of perioperative stroke. Among 8224 children who had a first cardiac transplant, 255 (3%) had a perioperative stroke. Black children had 32% lower odds of perioperative stroke compared with White children (adjusted odds ratio, 0.68 [95% CI, 0.46–0.996]). Following perioperative stroke, mortality rates were similar for Black and White children in the first 6 months (adjusted hazard ratio [HR], 0.99 [95% CI, 0.44–2.26]). However, Black children had a higher mortality rate than White children beyond 6 months (adjusted HR, 3.36 [95% CI, 1.22–9.22]).

Conclusions

Among pediatric cardiac transplant recipients, Black children have a lower incidence of perioperative stroke than White children. Among survivors of perioperative stroke, mortality is initially similar by race and ethnicity, but beyond 6 months, Black children have over a 3‐fold higher mortality rate than White children. Identifying and intervening on potential differences in care is essential to addressing these disparities.

Racial and Ethnic Disparities Persist in the Current Era of Pediatric Heart Transplantation

BACKGROUND

Previous studies have demonstrated that children in the United States who were of racial and ethnic minorities have inferior waitlist and post-heart transplant (HT) outcomes. Whether these disparities still exist in the contemporary era of increased ventricular assist device use remains unknown.

METHODS

All children (age <18 years) in the Scientific Registry of Transplant Recipients database listed for HT from December 2011 to February 2019 were included and were separated into 5 races/ethnicities: Caucasian, African American, Hispanic, Asian, and Other. Differences in clinical characteristics and survival among children of different racial/ethnic groups were compared at listing and at HT.

RESULTS

The waitlist cohort consisted of 2134 (52.2%) Caucasian, 840 (20.5%) African American, 808 (19.8%) Hispanic, 161 (3.9%) Asian, and 146 children of Other races (3.6%). At listing, Asian children mostly had cardiomyopathy (70.8%), whereas Caucasian children had congenital heart disease (58.7%). African American children were most likely to be listed as Status 1A and to have renal dysfunction and hypoalbuminemia at listing. African American and Hispanic children were most likely to be on Medicaid. After multivariable analysis, it was found that only African American children were at increased risk for waitlist mortality as compared to Caucasian children (adjusted hazard ratio = 1.25; P = 0.029). Post-HT, there were no disparities in early and midterm graft survival among groups, but African American children had increased numbers of rejection episodes compared to Caucasian and Hispanic children.

CONCLUSION

African American children continue to experience increased waitlist mortality and have increased rejection episodes post-HT. Studies exploring barriers to health care access and implicit bias as reasons for these disparities need to be conducted.

Examining racial and socioeconomic disparity in the pediatric heart transplant evaluation

Racial disparities have been reported among pediatric patients waitlisted for and undergoing heart transplantation but have not been studied further upstream in the transplant candidate evaluation process. We retrospectively studied our single-center experience in order to investigate any potential biases in the evaluation process. Results of the heart transplant evaluation in children ≤18 years old at our institution were analyzed. Primary outcome was final disposition to waitlist or not. Race was defined by family self-identification. Descriptive and comparative statistical analyses were performed. From 2013 to 2019, 133 unique patients were referred for listing consideration. While Black patients comprised 44% of the referral population and had more markers of socioeconomic disadvantage, they comprised 43% of the patients who were listed for transplantation with no significant difference between these proportions (p = .96). Black and White patients made up a similar proportion of patients deemed too well or too ill for listing. Black patients had lower annual household income estimates and rates of household marriage. Despite identifying significant social challenges in 27 patients (18 of them Black), only five patients (3 Black and 2 White) were turned down for listing due to social barriers. While limited by the small number of patients turned down for social barriers, our transplant evaluation process does not appear to result in racial disparities in access to listing. Further studies are needed using national cohorts to explore possible racial disparities upstream from waitlisting and transplantation, such as during the referral and evaluation.

Racial differences in attitudes to clinical pig organ Xenotransplantation

INTRODUCTION

In addition to an organ donor shortage, racial disparities exist at different stages of the transplantation process. Xenotransplantation (XTx) could alleviate these issues. This study describes racial differences in attitudes to XTx among populations who may need a transplant or are transplant recipients.

METHODS

A Likert-scale survey was distributed at outpatient clinics to parents of children with congenital heart disease (CHD) and kidney patients on their attitudes to pig organ XTx. Data from these two groups were stratified by race and compared.

RESULTS

Ninety-seven parents of children with CHD (74.2% White and 25.8% Black) and 148 kidney patients (50% White and 50% Black) responded to our survey. Black kidney patients' acceptance of XTx although high (70%) was lower than White kidney patients (91%; P .003). White kidney patients were more likely to accept XTx if results are similar to allotransplantation (OR 4.14; 95% CI 4.51-11.41), and less likely to be concerned with psychosocial changes when compared to Black kidney patients (receiving a pig organ would change your personality OR 0.08; 95% CI 0.01-0.67 and would change social interaction OR 0.24; 95% CI 0.07-0.78). There were no racial differences in attitudes to XTx among parents of children with CHD.

CONCLUSION

There are differences in attitudes to XTx particularly among Black kidney patients. Because kidneys may be the first organ for clinical trials of XTx, future studies that decrease scientific mistrust and XTx concerns among the Black community are needed to prevent disparities in uptake of possible future organ transplant alternatives.

Center effect on posttransplant survival among currently active United States pediatric heart transplant centers

The official analysis of posttransplant survival considers only recently transplanted patients and suggests absence of outcome differences among pediatric heart transplant (HT) centers. We sought to compare posttransplant survival among currently active pediatric HT centers in the United States over 15 years of activity. We identified all children <18 years old who underwent their first HT during 2000-2014 at US centers active during 2013-14. Recipients were followed until March 2016. A mixed-effects survival model with center as a random effect was used to assess center differences in patient and graft survival. Center case-mix and standardized mortality ratio (SMR) for 90-day mortality were assessed by applying an internally validated risk-model. Overall, 4271 children transplanted at 46 centers were analyzed. There was a significant center effect on risk-adjusted patient (P = .01) and graft survival (P < .001). Adjusting for 90-day SMR or center-volume, but not for case-mix, was associated with a significant reduction in center effect on long-term survival. There was no center effect on conditional survival in 90-day survivors. In conclusion, there are significant differences in posttransplant survival among pediatric HT centers in the United States. Centers with better short-term performance (lower SMR for 90-day mortality) maintain their outcome advantage on follow-up and have superior longer-term outcomes.

Pediatric Heart Transplantation Long-Term Survival in Different Age and Diagnostic Groups: Analysis of a National Database

BACKGROUND

The purpose of this study was to evaluate differences in long-term survival without the influence of early mortality, and to identify factors associated with one-year conditional ten-year survival after heart transplantation (HTx) across different age and diagnostic groups.

METHODS

Organ Procurement and Transplant Network data from January 1990 to December 2005 were used. Cohort was divided according to age (infants [<1 year], children [>1-10 years], and adolescents [11-18 years]) and diagnosis (cardiomyopathy and congenital heart disease [CHD]). Factors associated with one-year conditional ten-year survival were identified using multivariable logistic regression and using a case-control design.

RESULTS

One-year conditional ten-year survivors included 1,790 patients compared to 1,114 patients who died after the first posttransplant year and within ten years of transplant with a median follow-up of 4.8 years. Predictors of one-year conditional ten-year survival for infants were recipient's Caucasian race (odds ratio [OR]: 1.9, 95% confidence interval [CI]: 1.3-2.7) and donor-recipient weight ratio (OR: 0.8, 95% CI: 0.6-1); for children: Caucasian race (OR: 1.6, 95% CI: 1.2-2.1), retransplantation (OR: 0.4, 95% CI: 0.2-0.6), and transplantation after the year 2000 (OR: 1.5, 95% CI: 1.1-2.1); for adolescents only Caucasian race (OR: 2.5, 95% CI: 1.9-2.3). In both CHD and cardiomyopathy, adolescents had worse survival compared to infants and children. There was an era effect with improved survival after 2000. Male gender was a predictor of survival in cardiomyopathy group.

CONCLUSION

Predictors of one-year conditional ten-year survival varied among groups. These data and analyses provide important information that may be useful to clinicians, particularly when counseling patients and families regarding expectations of survival after pediatric HTx.

Predictors of Poor Outcomes in Pediatric Venoarterial Extracorporeal Membrane Oxygenation

BACKGROUND

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) provides respiratory and hemodynamic support to pediatric patients in severe cardiac failure. We aim to identify risk factors associated with poorer outcomes in this population.

METHODS

A retrospective chart review was conducted of pediatric patients requiring VA-ECMO support for cardiac indications at our institution from 2004 to 2015. Data were collected on demographics, indication, markers of cardiac output, ventricular assist device (VAD) insertion, heart transplantation, or left atrial (LA) decompression. Univariate Cox proportional hazards models were used to calculate hazard ratios (HRs) for variables associated with the composite primary outcome of transplant-free survival (TFS).

RESULTS

Of the 68 reviewed patients, 65% were male, 84% were white, 38% had a prior surgery, 13% had a prior transplant, 10% had a prior ECMO support, and 87.5% required vasoactive support within six hours of cannulation. The ECMO indications included congenital heart disease repaired >30 days prior (12%), cardiomyopathy (41%), posttransplant rejection (7%), and cardiorespiratory failure (40%). The TFS was 54.5% at discharge and 47.7% at one year. Predictors of transplant and/or death include epinephrine use (hazard ratio [HR] = 2.269, P = .041), elevated lactate (HR = 1.081, P = 0005), and elevated creatinine (HR = 1.081, P = .005) within six hours prior to cannulation. Sixteen (23.6%) patients underwent LA decompression. Placement of VAD occurred in 16 (23.5%) patients, for which nonwhite race (HR = 2.94, P = .034) and prior ECMO (HR = 3.42, P = .053) were the only identified risk factors.

CONCLUSIONS

Need for VA-ECMO for cardiac support carries high inpatient morbidity and mortality. Epinephrine use and elevated lactate and creatinine were associated with especially poor outcomes. Patients who survived to discharge had good short-term follow-up results.

The Influence of Race and Common Genetic Variations on Outcomes After Pediatric Heart Transplantation

Significant racial disparity remains in the incidence of unfavorable outcomes following heart transplantation. We sought to determine which pediatric posttransplantation outcomes differ by race and whether these can be explained by recipient demographic, clinical, and genetic attributes. Data were collected for 80 black and 450 nonblack pediatric recipients transplanted at 1 of 6 centers between 1993 and 2008. Genotyping was performed for 20 candidate genes. Average follow-up was 6.25 years. Unadjusted 5-year rates for death (p = 0.001), graft loss (p = 0.015), acute rejection with severe hemodynamic compromise (p = 0.001), late rejection (p = 0.005), and late rejection with hemodynamic compromise (p = 0.004) were significantly higher among blacks compared with nonblacks. Black recipients were more likely to be older at the time of transplantation (p < 0.001), suffer from cardiomyopathy (p = 0.004), and have public insurance (p < 0.001), and were less likely to undergo induction therapy (p = 0.0039). In multivariate regression models adjusting for age, sex, cardiac diagnosis, insurance status, and genetic variations, black race remained a significant risk factor for all the above outcomes. These clinical and genetic variables explained only 8-19% of the excess risk observed for black recipients. We have confirmed racial differences in survival, graft loss, and several rejection outcomes following heart transplantation in children, which could not be fully explained by differences in recipient attributes.

Predictors of cardiac allograft vasculopathy in pediatric heart transplant recipients

CAV remains a leading cause of late graft loss and mortality among survivors of pediatric heart transplantation. We sought to define the incidence of CAV and identify its predictors in pediatric heart transplant recipients. The OPTN/UNOS database was analyzed for pediatric recipients who underwent heart transplant between 1987 and 2011. The primary end-point is time from heart transplantation to development of CAV (CAV-free survival). To identify predictors of CAV-free survival, demographic and transplant data were analyzed by the Kaplan-Meier survival method and Cox proportional hazards regression. Of 5211 pediatric heart transplant recipients with at least one-yr follow-up, the incidence of CAV at five, 10, and 15 yr was 13%, 25%, and 54%, respectively. Multivariate analysis found that risk of CAV was associated with the following variables: Recipient age 1-4 yr (HR 1.25), 5-9 yr (1.45), 10-18 yr (1.83), donor age >18 yr (1.34), re-transplantation (2.14), recipient black race (1.55), and donor cigarette use (1.54). Older recipient and donor age, recipient black race, donor cigarette use, and re-transplantation were highly associated with shorter CAV-free survival.

Current Outcomes in US Children With Cardiomyopathy Listed for Heart Transplantation

Background—

Previous studies have reported worse outcomes in children with nondilated cardiomyopathy (CMP) listed for heart transplant compared with children with dilated CMP. We sought to compare wait-list and posttransplant outcomes in these groups in the current era.

Methods and Results—

We analyzed all children <18 years of age with a diagnosis of CMP listed for heart transplant in the United States between July 2004 and December 2010. Multivariable risk factors for death on the wait-list (or becoming too sick to transplant) and posttransplant graft loss (median follow-up 2 years) were assessed using Cox models. Of the 1436 children analyzed, 1197 (83%) had dilated CMP and 239 (17%) had nondilated CMP (167 restrictive CMP, 72 hypertrophic CMP). In adjusted analysis, children with nondilated CMP were at higher risk of wait-list mortality only if they were on a ventilator support at listing (hazard ratio, 2.3; CI, 1.2–4.5). The risk was similar among children not on a ventilator support (hazard ratio, 0.6; CI, 0.3–1.1). Posttransplant 30-day and 1-year survival was 98% and 94%, respectively, in children with dilated CMP versus 95% and 89%, respectively, in children with nondilated CMP ( P =0.17, log-rank test). In adjusted analysis, the risk of posttransplant graft loss was higher in nondilated CMP (hazard ratio, 1.8; CI, 1.2–2.7) versus dilated CMP.

Conclusions—

The increased risk of wait-list mortality in children with nondilated CMP is limited to those on ventilator support at listing. Although the risk of graft loss is modestly higher in children with nondilated forms of CMP, their short-term transplant outcomes are good.

Adult-derived Index for Mortality Prediction After Cardiac Transplantation (IMPACT) risk score predicts short-term mortality after pediatric heart transplantation

BACKGROUND

We have previously derived and validated the Index for Mortality Prediction After Cardiac Transplantation (IMPACT), which predicts short-term mortality after adult orthotopic heart transplantation (OHT). This study evaluated the predictive accuracy of the IMPACT score in pediatric OHT.

METHODS

The United Network for Organ Sharing registry was used to identify pediatric (< 18 years) OHT patients from 2000 to 2008. The IMPACT score was calculated for each patient. The association of IMPACT score with 1-year mortality was evaluated with univariate and multivariable logistic regression analysis. The correlation coefficient between predicted and actual 1-year mortality was determined for each IMPACT score. Kaplan-Meier survival estimates were calculated and stratified by IMPACT score.

RESULTS

We identified 2,518 eligible pediatric OHT patients (1,128 girls [44.8%]). Mean IMPACT score was 10.3 ± 6.3 (range, 0 to 38). A total of 297 patients (11.8%) died within the first year after OHT. Each point increase in the IMPACT score increased the odds of 1-year mortality by 13% (odds ratio, 1.13; 95% confidence interval, 1.11 to 1.15; p < 0.001). The correlation coefficient between predicted and actual 1-year mortality was 0.93 (p < 0.001). One-year survival by disjoint categories of the IMPACT score was 0 to 4 (96.7%), 5 to 9 (92.9%), 10 to 14 (87.6%), 15 to 19 (81.3%), and 20 or more (64.2%; p < 0.001).

CONCLUSIONS

In this large-cohort analysis, the IMPACT score accurately predicted mortality following pediatric OHT. The IMPACT score could therefore be useful to providers for organ allocation and prognostication in this patient population.

Trends in wait-list mortality in children listed for heart transplantation in the United States: era effect across racial/ethnic groups

We sought to evaluate trends in overall and race-specific pediatric heart transplant (HT) wait-list mortality in the United States (US) during the last 20 years. We identified all children <18 years old listed for primary HT in the US during 1989-2009 (N = 8096, 62% White, 19% Black, 13% Hispanic and 6% Other) using the Organ Procurement and Transplant Network database. Wait-list mortality was assessed in four successive eras (1989-1994, 1995-1999, 2000-2004 and 2005-2009). Overall wait-list mortality declined in successive eras (26%, 23%, 18% and 13%, respectively). The decline across eras remained significant in adjusted analysis (hazard ratio [HR] 0.70 in successive eras, 95% confidence interval [CI], 0.67-0.74) and was 67% lower for children listed during 2005-2009 versus those listed during 1989-1994 (HR 0.33; CI, 0.28-0.39). In models stratified by race, wait-list mortality decreased in all racial groups in successive eras. In models stratified by era, minority children were not at higher risk of wait-list mortality in the most recent era. We conclude that the risk of wait-list mortality among US children listed for HT has decreased by two-thirds during the last 20 years. Racial gaps in wait-list mortality present variably in the past are not present in the current era.