Disparities in outcome for black patients after pediatric heart transplantation

Social Determinants of Health and Outcomes After Pediatric Ventricular Assist Device Implantation

BACKGROUND

Limited research exists on the influence of social determinants of health (SDOH) on outcomes in pediatric patients with advanced heart failure receiving mechanical circulatory support.

METHODS

Linkage of the Pediatric Interagency Registry for Mechanical Circulatory Support (Pedimacs) and Society of Thoracic Surgeon's Congenital Heart Surgery Database (STS-CHSD) identified pediatric patients who underwent ventricular assist device (VAD) implantation from 2012 to 2022 with available residential zip codes. Utilizing the available zip codes, each patient was assigned a Childhood Opportunity Index (COI) score. Level of childhood opportunity, race, and insurance type were used as proxies for SDOH. Major outcomes included death, transplant, alive with device, and recovery. Secondary outcomes were adverse events. Statistical analyses were performed using the Kaplan-Meier survival, competing risk analyses, and multivariable Cox proportional hazards model.

RESULTS

Three hundred seventeen patients were included in the study. Childhood opportunity level and insurance status did not significantly impact morbidity or mortality after VAD implantation. White race was associated with reduced 1-year survival (71% in White vs. 87% in non-White patients, p = 0.05) and increased risk of pump thrombosis (p = 0.02).

CONCLUSION

Childhood opportunity level and insurance status were not linked to morbidity and mortality in pediatric patients after VAD implantation. Notably, White race was associated with higher mortality rates. The study underscores the importance of considering SDOH in evaluating advanced therapies for pediatric heart failure and emphasizes the need for accurate socioeconomic data collection in future studies and national registries.

Outcomes of heart transplantation in children with previously palliated hypoplastic left heart syndrome

OBJECTIVES

Paediatric heart transplantation in children who fail multistage palliation for hypoplastic left heart syndrome is associated with challenges related to immune, clinical or anatomic risk factors. We review current outcomes and risk factors for survival following heart transplantation in this challenging patient population.

METHODS

The United Network for Organ Sharing transplantation database was merged with Paediatric Health Information System database to identify children who received heart transplantation following prior palliation for hypoplastic left heart syndrome. Multivariable Cox analysis of outcomes and factors affecting survival was performed.

RESULTS

Our cohort included 849 children between 2009 and 2021. The median age was 1044 days (interquartile range 108-3535), and the median weight was 13 kg (interquartile range 7-26). Overall survival at 10 years following heart transplantation was 71%, with most of the death being perioperative. On multivariable analysis, risk factors for survival included Black race (hazard ratio = 1.630, P = 0.0253), blood type other than B (hazard ratio = 2.564, P = 0.0052) and male donor gender (hazard ratio = 1.367, P = 0.0483). Recipient age, the use of ventricular assist device or extracorporeal membrane oxygenation were not significantly associated with survival. Twenty-four patients underwent retransplantation, and 10-year freedom from retransplantation was 98%. Rejection before hospital discharge and within 1 year from transplantation was 20% and 24%, respectively, with infants having lower rejection rates.

CONCLUSIONS

Compared with existing literature, the number of children with prior hypoplastic left heart syndrome palliation who receive heart transplantation has increased in the current era. Survival following transplantation in this patient population is acceptable. Most of the death is perioperative. Efforts to properly support these patients before transplantation might decrease early mortality and improve overall survival.

DQB1 antigen matching improves rejection-free survival in pediatric heart transplant recipients

BACKGROUND

Presence of donor-specific antibodies (DSAs), particularly to class II antigens, remains a major challenge in pediatric heart transplantation. Donor-recipient human leukocyte antigen (HLA) matching is a potential strategy to mitigate poor outcomes associated with DSAs. We evaluated the hypothesis that antigen mismatching at the DQB1 locus is associated with worse rejection-free survival.

METHODS

Data were collected from Scientific Registry of Transplant Recipients for all pediatric heart transplant recipients 2010-2021. Only transplants with complete HLA typing at the DQB1 locus for recipient and donor were included. Primary outcome was rejection-free graft survival through 5 years.

RESULTS

Of 5,115 children, 4,135 had complete DQB1 typing and were included. Of those, 503 (12%) had 0 DQB1 donor-recipient mismatches, 2,203 (53%) had 1, and 1,429 (35%) had 2. Rejection-free survival through 5 years trended higher for children with 0 DQB1 mismatches (68%), compared to those with 1 (62%) or 2 (63%) mismatches (pairwise p = 0.08 for both). In multivariable analysis, 0 DQB1 mismatches remained significantly associated with improved rejection-free graft survival compared to 2 mismatches, while 1 DQB1 mismatch was not. Subgroup analysis showed the strongest effect in non-Hispanic Black children and those undergoing retransplant.

CONCLUSIONS

Matching at the DQB1 locus is associated with improved rejection-free survival after pediatric heart transplant, particularly in Black children, and those undergoing retransplant. Assessing high-resolution donor typing at the time of allocation may further corroborate and refine this association. DQB1 matching may improve long-term outcomes in children stabilized either with optimal pharmacotherapy or supported with durable devices able to await ideal donors.

The effect of socioeconomic status on pediatric heart transplant outcomes at a single institution between 2013 and 2022

BACKGROUND

Disparities in pediatric heart transplant outcomes based on socioeconomic status (SES) have been previously observed. However, there is a need to reevaluate these associations in contemporary settings with advancements in transplant therapies and increased awareness of health disparities. This retrospective study aims to investigate the relationship between SES and outcomes for pediatric heart transplant patients.

METHODS

Data were collected through a chart review of 176 pediatric patients who underwent first orthotopic heart transplantation (OHT) at a single center from 2013 to 2021. The Area Deprivation Index (ADI), a composite score based on U.S. census data, was used to quantify SES. Cox proportional hazards models and generalized linear models were employed to analyze the association between SES and graft failure, rejection rates, and hospitalization rates.

RESULTS

The analysis revealed no statistically significant differences in graft failure rates, rejection rates, or hospitalization rates between low-SES and high-SES pediatric heart transplant patients for our single-center study.

CONCLUSION

There may be patient education, policies, and social resources that can help mitigate SES-based healthcare disparities. Additional multi-center research is needed to identify post-transplant care that promotes patient equity.

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.

Socioeconomic Disparities in Surgical Care for Congenital Hand Differences

BACKGROUND

The purpose of this study was to evaluate the influence of socioeconomic factors on access to congenital hand surgery care, hospital admission charges, and analyze these geographic trends across regions of the country.

METHODS

Retrospective cohort study was conducted of congenital hand surgery performed in the United States from 2010 through 2020 using the Pediatric Health Information System. Multivariate regression was used to analyze the impact of socioeconomic factors.

RESULTS

During the study interval, 5531 pediatric patients underwent corrective surgery for congenital hand differences, including syndactyly repair (n = 2439), polydactyly repair (n = 2826), and pollicization (n = 266). Patients underwent surgery at significantly earlier age when treated at above-median case volume hospitals (P < .001). Patients with above-median income (P < .001), non-white race (P < .001), commercial insurance (P < .001), living in an urban community (P < .001), and not living in an underserved area (P < .001) were more likely to be treated at high-volume hospitals. Nearly half of patients chose to seek care at a distant hospital rather than the one locally available (49.5%, n = 1172). Of those choosing a distant hospital, most patients chose a higher-volume facility (80.9%, n = 948 of 1172). On multivariate regression, white patients were significantly more likely to choose a more distant, higher-volume hospital (P < .001).

CONCLUSIONS

Socioeconomic and geographic factors significantly contribute to disparate access to congenital hand surgery across the country. Patients with higher socioeconomic status are more likely to be treated at high-volume hospitals. Treatment at hospitals with higher case volume is associated with earlier age at surgery and decreased hospital admission charges.

Racial and Ethnic Disparities in U.S Children Undergoing Surgery for Congenital Heart Disease: A Narrative Literature Review

Congenital Heart Disease (CHD) is a significant source of pediatric morbidity and mortality. As in other fields of medicine, studies have demonstrated racial and ethnic disparities in congenital heart disease outcomes. The cause of these outcome disparities is multifactorial, involving biological, behavioral, environmental, sociocultural, and systemic medical factors. Potential contributors include differences in preoperative illness severity secondary to coexisting medical conditions, differences in the rate of prenatal and early postnatal detection of CHD, and delayed access to care, as well as discrepancies in socioeconomic and insurance status, and systemic disparities in hospital care. Understanding the factors that contribute to these disparities is an essential step towards developing strategies to address them. As stewards of the perioperative surgical home, anesthesiologists have an important role in developing institutional policies that mitigate racial disparities. Here, we provide a thorough narrative review of recent research concerning perioperative factors contributing to surgical outcomes disparities for children of all ages with CHD, examine potentially modifiable contributing factors, discuss avenues for future research, and suggest strategies to address disparities both locally and nationally.

Extracorporeal membrane oxygenation bridge to pediatric lung transplantation: Modern era analysis

BACKGROUND

Survival outcomes of children on extracorporeal membrane oxygenation (ECMO) at time of lung transplant (LTx) remain unclear.

METHODS

Pediatric first-time LTx recipients transplanted between January 2000 and December 2020 were identified in the United Network for Organ Sharing Registry to compare post-transplant survival according to ECMO support at time of transplant. For a comprehensive analysis of the data, univariate analysis, multivariable Cox regression, and propensity score matching were performed.

RESULTS

During the study period, 954 children under 18 years of age underwent LTx with 40 patients on ECMO. We did not identify a post-LTx survival difference between patients receiving ECMO when compared to those that did not. A multivariable Cox regression model (Hazard ratio = 0.83; 95% confidence interval: 0.47, 1.45; p = .51) did not demonstrate an increased risk for death post-LTx. Lastly, a propensity score matching analysis, retaining 33 ECMO and 33 non-ECMO patients, further confirmed no post-LTx survival difference comparing ECMO to no ECMO cohorts (Hazard ratio = 0.98; 95% confidence interval: 0.48, 2.00; p = .96).

CONCLUSIONS

In this contemporary cohort of children, the use of ECMO at the time of LTx did not negatively impact post-transplant survival.

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.

Surgical Management of Facial Paralysis: Demographic and Socioeconomic Associations

Objective: To determine demographic and socioeconomic variables associated with whether surgery is performed for patients with facial paralysis (FP). Background: Management of FP may include elective surgery dependent on patient goals of care and physician experience. Methods: The 2016 State Inpatient Database and State Ambulatory Surgery Services Database for six states were queried to identify patients with FP. These patients were then stratified based on receiving surgery for FP. Demographic and socioeconomic information was collected. Multivariable logistic regression modeling was used to identify predictors of undergoing FP surgery, as well as the hospital setting in which surgery was performed. Results: Of 20,218 patients with FP, 515 underwent surgery. Black patients were significantly less likely to undergo surgery (p < 0.001), as were patients with Medicaid or self-pay insurance (p < 0.001). Those living in rural areas were also less likely to receive surgery (p = 0.001). Individuals receiving surgery in the inpatient setting were more likely to have private insurance, whereas those in the ambulatory setting were more likely to have Medicare (p < 0.001). Conclusion: Several variables are correlated with whether FP is managed surgically, including insurance status, race, and type of residential area.

Trends in Contemporary Use of Ventricular Assist Devices in Children Awaiting Heart Transplantation and Their Outcomes by Race/Ethnicity

This retrospective study included children aged ≤18 years who had durable ventricular assist devices (VADs) as a bridge to transplantation from the United Network Organ Sharing (UNOS) database between 2011 and 2020. We evaluated 90 day waitlist mortality and 1 year posttransplant mortality after VAD implantation in children stratified by race/ethnicity: Black, White, and Others. The VAD was used in a higher proportion of Black children listed for heart transplantation (HT) (26%) versus Other (25%) versus White (22%); p < 0.01. Black children had Medicaid health insurance coverage (67%) predominantly at the time of listing for HT. There was no significant overall difference in waitlist survival among the three groups supported with VAD at the time of listing (log-rank p = 0.4). On the other hand, the 90 day waitlist mortality after the VAD implantation at listing and while listed was the lowest among Black (6%) compared with White (13%) and Other (14%) ( p < 0.01). The multivariate regression analysis showed that Other race (hazard ratio [HR], 2.29; p < 0.01), Black race (HR, 2.13; p < 0.01), use of mechanical ventilation (HR, 1.72; p = 0.01), and Medicaid insurance (HR, 1.54; p = 0.04) were independently associated with increased 1 year posttransplant mortality. In conclusion, Black children had more access to durable VAD support than White children. The 90 day waitlist mortality was significantly lower in Black children compared with White and Other after VAD implantation. However, Black and Other racial/ethnic children with VAD at transplant had higher 1 year posttransplant mortality than White children. Future studies to elucidate the reasons for these disparities are needed.

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.

Race and Socioeconomic Bias in Pediatric Cardiac Transplantation

BACKGROUND

To date, no studies evaluated implicit bias among clinicians caring for children with advanced heart failure.

OBJECTIVES

This study aims to evaluate implicit racial and socioeconomic bias among pediatric heart transplant clinicians.

METHODS

A cross-sectional survey of transplant clinicians from the Pediatric Heart Transplant Society was conducted between June and August 2021. The survey consisted of demographic questions along with explicit and validated race and socioeconomic status (SES) implicit association tests (IATs). Implicit and explicit biases among survey group members were studied and associations were tested between implicit and explicit measures.

RESULTS

Of 500 members, 91 (18.2%) individuals completed the race IAT and 70 (14%) completed the SES IAT. Race IAT scores indicated moderate levels of implicit bias (mean = 0.33, d = 0.76; P < 0.001; ie, preference for White individuals). SES IAT scores indicated strong implicit bias (mean = 0.52, d = 1.53; P < 0.001; ie, preference for people from upper SES). There were weak levels of explicit race and wealth bias. There was a strong level of explicit education bias (mean = 5.22, d = 1.19; P < 0.001; ie, preference for educated people). There were nonsignificant correlations between the race and the SES IAT and explicit measures (P > 0.05 for all).

CONCLUSIONS

As observed across other health care disciplines, among a group of pediatric heart transplant clinicians, there is an implicit preference for individuals who are White and from higher SES, and an explicit preference for educated people. Future studies should evaluate how implicit biases affect clinician behavior and assess the impact of efforts to reduce such biases.

Waitlist and post-transplant outcomes for children with myocarditis listed for heart transplantation over 3 decades

BACKGROUND

There is limited and conflicting information on waitlist and transplant outcomes for children with myocarditis.

METHODS

Retrospective review included children with myocarditis and dilated cardiomyopathy (DCM) listed for HT from January 01, 1993 to December 31, 2019 in the Pediatric Heart Transplant Society database. Clinical characteristics, waitlist and post-HT outcomes (graft loss, rejection, cardiac allograft vasculopathy, infection and malignancy) for children listed from early (1993-2008) and current era (2009-2019) with myocarditis were evaluated and compared to those with DCM.

RESULTS

Of 9755 children listed, 322 (3.3%) had myocarditis and 3178 (32.6%) DCM. Compared to DCM, children with myocarditis in the early and the current era were significantly more likely to be listed at higher urgency; be in intensive care unit; on mechanical ventilation; extracorporeal membrane oxygenation and ventricular assist device (p < 0.05 for all). While unadjusted analysis revealed lower transplant rates and higher waitlist mortality for children with myocarditis, in multivariable analysis, myocarditis was not a risk factor for waitlist mortality. Myocarditis, however, was a significant risk factor for early phase post-HT graft loss (HR 2.46; p = 0.003). Waitlist and post-HT survival for children with myocarditis were similar for those listed and transplanted in the early era to those listed and transplanted in the current era (p > 0.05 for both).

CONCLUSIONS

Children with myocarditis have a higher acuity of illness at listing and at HT and have inferior post-HT survival compared to children with DCM. Outcomes for children with myocarditis have not improved over the 3 decades and efforts are needed to improve outcomes for this cohort.

Worsening racial disparity in waitlist mortality for pediatric heart transplant candidates since the 2016 Pediatric Heart Allocation Policy revision

BACKGROUND

The US Pediatric Heart Allocation Policy (PHAP) was revised in March 2016, with the goal of reducing waitlist mortality. We evaluated the hypothesis that these changes, which increased status exceptions, have worsened racial disparities in waitlist outcomes.

METHODS

Children in the Pediatric Heart Transplant Study database listed for first heart transplant from January 2012 - June 2020 were included and stratified by listing before (Era 1) or after (Era 2) the PHAP revision.

RESULTS

A total of 4,089 children were listed during the study period. Compared with white children (n = 2648), non-white children (n = 1441) were more likely to have an underlying diagnosis of cardiomyopathy in both eras. Waitlist mortality was similar in white and non-white children in Era 1, but comparatively worse for non-white children in Era 2. In multivariable analysis controlling for diagnosis, age, and severity markers, non-white children had a significantly higher waitlist mortality only in Era 2 (Era 1: sHR 1.22 [95%CI 0.90 - 1.66] vs. Era 2: sHR 1.57 [95%CI 1.17 - 2.10]).

CONCLUSIONS

Widening racial disparities in waitlist mortality may be an unintended consequence of the 2016 PHAP revision. Additional analyses may inform the degree to which this policy vs. unrelated changes in care differentially contribute to these disparities.

Risk factors and outcomes of sudden cardiac arrest in pediatric heart transplant recipients

BACKGROUND

Sudden cardiac arrest (SCA) is a prevailing cause of mortality after pediatric heart transplant (HT) but remains understudied. We analyzed the incidence, outcomes, and risk factors for SCA at our center.

METHODS

Retrospective review of all pediatric HT patients at our center from January 1, 2009 to January 1, 2021. SCA was defined as an abrupt loss of cardiac function requiring cardiopulmonary resuscitation and/or mechanical circulatory support (MCS). Events that occurred in the setting of limited resuscitative wishes, or while on MCS were excluded. Patient characteristics and risk factors were analyzed.

RESULTS

Fourteen of 254 (6%) experienced SCA at a median of 3 (1, 4) years post-HT. Seven (50%) events occurred out-of-hospital. Eleven (79%) died from their initial event, 2 (18%) after failure to separate from extracorporeal membrane (ECMO). In univariate analysis, black race, younger donor age, prior acute cellular rejection (ACR) episode, pacemaker and/or ICD in place, and pre-mortem diagnosis of allograft vasculopathy were associated with SCA (P = .003-0.02). In multivariable analysis, history of ACR, younger donor age, and black race retained significance. [OR = 6.3, 95% CI: 1.6-25.4, P = .01], [OR = 0.9, 95% CI: 0.8-1, P = .04], and [OR = 7.3, 95% CI: 1.1-49.9, P = .04], respectively. SCA occurred in 3 patients with a functioning ICD or pacemaker, which failed to restore a perfusing rhythm.

CONCLUSIONS

SCA occurs relatively early after pediatric HT and is usually fatal. Half of events happen at home. Those who received younger donors, have a history of ACR, or are of black race are at increased risk. ICDs/pacemakers may offer limited protection.

Postoperative physiological parameters associated with severe acute kidney injury after pediatric heart transplant

BACKGROUND

The primary objective was to evaluate associations between perioperative clinical variables and postoperative hemodynamic indices after HT with the development of severe AKI. The secondary objective was to evaluate associations between UOP or creatinine as AKI indicators and morbidity after HT.

METHODS

Retrospective study of all patients who underwent HT 1/2016-11/2019 at a quaternary pediatric institution. Severe AKI was defined as KDIGO stage 2 or higher.

RESULTS

Of 94 HT patients, 73 met inclusion criteria; 45% of patients developed severe AKI. In univariate analysis, non-Hispanic Black race, preoperative AKI, longer CPB duration, lower weight, and peak lactate within 12 h post-HT were associated with severe AKI. CVP ≤12 h post-HT had a quadratic relationship, rather than linear, with severe AKI. PPV >18% was significantly associated with severe AKI but equated to noncontiguous 10 min of high variation over a 12-h period, and thus was deemed not clinically significant. In multivariate analysis, Black race, longer CPB duration, and higher CVP remained associated with severe AKI (c: 0.84, 95% CI 0.73-0.92). Severe AKI per creatinine, but not UOP criteria, was associated with longer duration of ventilation (p = .012) and longer intensive care unit length of stay (p = .003).

CONCLUSIONS

In pediatric HT patients, non-Hispanic Black race, longer CPB time, and higher postoperative CVP ≤12 h post-HT were associated with severe AKI. AKI based on creatinine, not UOP, was associated with postoperative HT morbidity.

Socioeconomic factors associated with pediatric moyamoya disease hospitalizations: a nationwide cross-sectional study

OBJECTIVE

Healthcare disparities are widely described in adults, but barriers affecting access to care for pediatric patients with moyamoya disease (MMD) are unknown. Understanding socioeconomic factors impacting hospital access and outcomes is necessary to address pediatric healthcare disparities.

METHODS

In this cross-sectional observational study, the Kids' Inpatient Database was used to identify patients admitted with a primary diagnosis of MMD from 2003 to 2016. Patients ≤ 18 years with a primary diagnosis of MMD based on International Classification of Diseases (ICD) codes were included. Hospital admissions were queried for use of cerebral revascularization based on ICD procedure codes.

RESULTS

Query of the KID yielded 1449 MMD hospitalizations. After multivariable regression, Hispanic ethnicity (OR 0.52 [95% CI 0.33-0.81], p = 0.004) was associated with lack of surgical revascularization. Private insurance (OR 1.56 [95% CI 1.15-2.13], p = 0.004), admissions at medium- and high-volume centers (OR 2.01 [95% CI 1.42-2.83], p < 0.001 and OR 2.84 [95% CI 1.95-4.14], p < 0.001, respectively), and elective hospitalization (OR 3.37 [95% CI 2.46-4.64], p < 0.001) were positively associated with revascularization. Compared with Caucasian race, Hispanic ethnicity was associated with increased mean (± SEM) length of stay by 2.01 ± 0.70 days (p = 0.004) and increased hospital charges by $24,333.61 ± $7918.20 (p = 0.002), despite the decreased utilization of surgical revascularization. Private insurance was associated with elective admission (OR 1.50 [95% CI 1.10-2.05], p = 0.01) and admission to high-volume centers (OR 1.90 [95% CI 1.26-2.88], p = 0.002). African American race was associated with the development of in-hospital complications (OR 2.52 [95% CI 1.38-4.59], p = 0.003).

CONCLUSIONS

Among pediatric MMD hospitalizations, multiple socioeconomic factors were associated with access to care, whether surgical treatment is provided, and whether in-hospital complications occur. These results suggest that socioeconomic factors are important drivers of healthcare disparities in children with MMD and warrant further study.

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.

An ethical analysis of obesity as a determinant of pediatric heart transplant candidacy

BACKGROUND

Inclusion of BMI as criterion in the determination of heart transplant candidacy in children is a clinical and ethical challenge. Childhood obesity is increasing and children with heart disease are not spared. Currently, many adult heart transplant centers consider class II obesity and higher (BMI > 35 kg/m² ) to be a relative contraindication for transplantation due to risk of poor outcome after transplant. No national guidelines exist regarding consideration of BMI in pediatric heart transplant and outcomes data are limited. This leaves decisions about transplant candidacy in obese pediatric patients to individual institutions or on a case-by-case basis, allowing for bias and inequity.

METHODS

We review (a) the prevalence of childhood obesity, including among heart transplant candidates, (b) the lack of existing BMI guidelines, and (c) relevant literature on BMI and pediatric heart transplant outcomes. We discuss the ethical considerations of using obesity as a criterion using the principles of utility, justice, and respect for persons.

RESULTS

Existing transplant outcomes data do not show that obese children have different or poor enough outcomes compared to non-obese children to warrant exclusion. Moreover, obesity in the United States is unequally distributed by race and socioeconomic status. Children already suffering from health disparities are therefore doubly penalized if obesity denies them access to life-saving transplant.

CONCLUSION

Insufficient data exist to support using any BMI cutoff as an absolute contraindication for heart transplant in children. Attention should be paid to health equity issues when considering excluding a patient for transplant based on obesity.

Increased Incidence of Chronic Kidney Injury in African Americans Following Cardiac Transplantation

OBJECTIVES

This study examined whether African American race was associated with an elevated risk of chronic kidney disease (CKD) post-cardiac transplantation.

BACKGROUND

CKD often occurs after cardiac transplantation and may require renal replacement therapy (RRT) or renal transplant. African American patients have a higher risk for kidney disease as well as worse post-cardiac transplant morbidity and mortality. It is unclear, however, if there is a propensity for African Americans to develop CKD after cardiac transplant.

METHODS

The Institutional Review Board of Columbia University Medical Center approved the retrospective study of 151 adults (57 African American and 94 non-African American) who underwent single-organ heart transplant from 2013 to 2016. The primary outcome was a decrease in estimated glomerular filtration rate (eGFR), development of CKD, and end-stage renal disease (ESRD) requiring RRT after 2 years.

RESULTS

African American patients had a significant decline in eGFR post-cardiac transplant compared to non-African American patients (- 34 ± 6 vs. - 20 ± 4 mL/min/1.73 m2, p < 0.0006). African American patients were more likely to develop CKD stage 2 or worse (eGFR < 90 mL/min/1.73 m2) than non-African American patients (81% vs. 59%, p < 0.0005).

CONCLUSIONS

This is the first study to report that African American patients are at a significantly higher risk for eGFR decline and CKD at 2 years post-cardiac transplant. Future investigation into risk reduction is necessary for this patient population.

Progress in research of enhanced recovery after surgery and surgery related differences

Enhanced recovery after surgery (ERAS) refers to the use of standardized, multimodal perioperative strategies to reduce physiological stress and organ dysfunction caused by surgery. Since the ERAS concept was put forward, it has been widely respected in the surgical field. Its benefits in the surgical field for the vast majority of patients, medical staff and healthcare systems are obvious. However, for some specific people undergoing surgery, the benefits are not certain, which is the so-called surgery-related differences. This article analyzes recent studies of different surgical fields related to surgical-related differences in different ethnic groups, reviews a large number of positive effects of the implementation of ERAS on surgical-related differences, and elaborates its possible mechanism. It is finally concluded that ERAS, a standardized model for resolving surgical-related differences, should become the gold standard for surgical perioperative management.

Comparison of 10-year graft failure rates after induction with basiliximab or anti-thymocyte globulin in pediatric heart transplant recipients-The influence of race

BACKGROUND/OBJECTIVE

The impact of induction therapy in pediatric heart transplantation has been uncertain. Given the risk of poor outcomes in black pediatric heart transplant recipients, we evaluated the effect on graft survival of ATG and BAS induction in black and non-black pediatric recipients.

METHODS

This was a retrospective analysis of pediatric candidates (aged ≤18 years) who underwent heart transplantation from 2000 to 2016 identified from the UNOS database. Primary outcome was 10-year graft survival.

RESULTS

This study included 654 patients receiving BAS, 2385 patients receiving ATG, and 2425 receiving no induction. Ten-year survival was similar for the following groups: non-black BAS (57%), non-black ATG (66%), and black ATG (51%). The black BAS group had a 10-year graft survival of 39% which was inferior on pairwise comparison to the other groups (all P values < 0.001). On multivariate analysis, ATG was associated with decreased risk of graft failure when compared to no induction (HR 0.86, 95% CI 0.76-0.97, P = 0.011) and had an association approaching statistical significance when compared to BAS induction (0.84, 0.7-1.01, P = 0.069). This association was seen in black recipients in whom ATG was strongly associated with decreased risk of graft failure when compared to either no induction (0.65, 0.5-0.83, P = 0.001) or BAS (0.64, 0.46-0.89, P = 0.008) but was not seen in non-black recipients.

CONCLUSIONS

Black pediatric heart transplant recipients who received ATG induction had an improved long-term graft survival compared to those who received BAS induction or no induction.

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.

Obesity class does not further stratify outcome in overweight and obese pediatric patients after heart transplantation

The effect of obesity stratification on pediatric heart transplant outcomes is unknown. The UNOS database was queried for patients ≥2-<18 years listed for heart transplant and stratified by BMI: normal (BMI>5%-≤85 percentile), overweight (BMI=86%-95 percentile), class 1 (BMI=100%-120% of 95 percentile), class 2 (BMI=121%-140% of 95 percentile), and class 3 obesity (BMI>140% of 95 percentile). A total of 5056 individuals were listed for transplant, with 71% normal, 13% overweight, 10% class 1, 4% class 2, and 2% class 3 obesity. Waitlist survival was not different between groups. Post-transplant survival was decreased in overweight and combined obese groups vs normal, with no further difference between overweight and obese classes. Overweight and obese patients had higher listing status and were more likely to have ventilator, inotrope, and mechanical circulatory support at listing. After transplant, there was an association of overweight-obese patients with diabetes and rejection requiring hospitalization. Stricter definition of normal weight reveals overweight-obese status was an independent risk factor for poorer post-transplant survival, without further effect by stratification of weight class. However, because there is no difference in waitlist survival, this study does not allow the selection of absolute weight-based criteria regarding transplant listing and suggests the need to look further for modifiable risk factors post-transplant.

County socioeconomic characteristics and heart transplant outcomes in the United States

BACKGROUND

Geographic disparities in survival after heart transplantation have received mixed support in prior studies, and specific geographic characteristics that might be responsible for these differences are unclear. We tested for differences in heart transplant outcomes across United States (US) counties after adjustment for individual-level covariates. Our secondary aim was to evaluate whether specific county-level socioeconomic characteristics explained geographic disparities in survival.

METHODS

Data on patients aged ≥18 years undergoing a first-time heart transplant between July 2006 and December 2014 were obtained from the United Network for Organ Sharing. Residents of counties represented by <5 patients were excluded. Patient survival (censored in March 2016) was analyzed using multivariable Cox regression. Shared frailty models were used to test for residual differences in overall all-cause mortality across counties after adjusting for recipient and donor characteristics. Measures of county economic disadvantage, inequality, and racial segregation were obtained from US Census data and coded into quintiles. A likelihood ratio test determined whether adjusting for each county measure improved the fit of the Cox model.

RESULTS

Multivariable analysis of 10,879 heart transplant recipients found that, adjusting for individual-level characteristics, there remained statistically significant variation in mortality hazard across US counties (P=.004). Adjusting for quintiles of community disadvantage, economic inequality, or racial segregation did not significantly improve model fit (likelihood ratio test P=.092, P=.273, and P=.107, respectively) and did not explain residual differences in patient survival across counties.

CONCLUSIONS

Heart transplantation outcomes vary by county, but this difference is not attributable to county-level socioeconomic disadvantage.

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.

Validation of a Simple Score to Determine Risk of Early Rejection After Pediatric Heart Transplantation

OBJECTIVES

This study aimed to develop a reliable and feasible score to assess the risk of rejection in pediatric heart transplantation recipients during the first post-transplant year.

BACKGROUND

The first post-transplant year is the most likely time for rejection to occur in pediatric heart transplantation. Rejection during this period is associated with worse outcomes.

METHODS

The United Network for Organ Sharing database was queried for pediatric patients (age <18 years) who underwent isolated orthotopic heart transplantation from January 1, 2000 to December 31, 2012. Transplantations were divided into a derivation cohort (n = 2,686) and a validation (n = 509) cohort. The validation cohort was randomly selected from 20% of transplantations from 2005 to 2012. Covariates found to be associated with rejection (p < 0.2) were included in the initial multivariable logistic regression model. The final model was derived by including only variables independently associated with rejection. A risk score was then developed using relative magnitudes of the covariates' odds ratio. The score was then tested in the validation cohort.

RESULTS

A 9-point risk score using 3 variables (age, cardiac diagnosis, and panel reactive antibody) was developed. Mean score in the derivation and validation cohorts were 4.5 ± 2.6 and 4.8 ± 2.7, respectively. A higher score was associated with an increased rate of rejection (score = 0, 10.6% in the validation cohort vs. score = 9, 40%; p < 0.01). In weighted regression analysis, the model-predicted risk of rejection correlated closely with the actual rates of rejection in the validation cohort (R(2) = 0.86; p < 0.01).

CONCLUSIONS

The rejection score is accurate in determining the risk of early rejection in pediatric heart transplantation recipients. The score has the potential to be used in clinical practice to aid in determining the immunosuppressant regimen and the frequency of rejection surveillance in the first post-transplant year.

Is Myocarditis an Independent Risk Factor for Post-Transplant Mortality in Pediatric Heart Transplant Recipients?

BACKGROUND

Previous studies suggest that children with myocarditis who receive heart transplantation (HT) may be at higher risk of post-transplant mortality compared with children who are transplanted for idiopathic dilated cardiomyopathy. We hypothesized that these differences are because of more severe heart failure at HT in children with myocarditis.

METHODS AND RESULTS

We identified 221 children with myocarditis and 1583 with idiopathic dilated cardiomyopathy who were <18 years old and listed for HT in the United States between July 2004 and December 2013 using the Organ Procurement and Transplant Network database. We compared baseline characteristics at listing and at HT and used Cox models to determine whether myocarditis is independently associated with wait-list mortality (or becoming too sick to transplant) or post-transplant graft loss (death/re-HT). Children with myocarditis were more likely to be listed while on assisted ventilation, mechanical circulatory support and with renal dysfunction. Overall, 137 children with myocarditis and 1249 with idiopathic dilated cardiomyopathy received HT. In unadjusted analysis, children with myocarditis were at higher risk of wait-list mortality (hazard ratio 2.1; 95% confidence interval 1.5-3.0) and showed a trend toward increased risk of post-transplant graft loss (hazard ratio 1.4; 95% confidence interval 1.0-2.2). However, in adjusted analysis, myocarditis was not associated with wait-list mortality (hazard ratio 1.3, 95% confidence interval 0.9-1.9) or post-transplant graft loss (hazard ratio 1.3, 95% confidence interval 0.9-2.0).

CONCLUSIONS

Among children listed for HT, those with myocarditis have more severe heart failure than children with idiopathic dilated cardiomyopathy. After adjustment for severity of illness, myocarditis does not confer additional risk for wait-list or post-transplant mortality.

High Risk of Graft Failure in Emerging Adult Heart Transplant Recipients

Emerging adulthood (17-24 years) is a period of high risk for graft failure in kidney transplant. Whether a similar association exists in heart transplant recipients is unknown. We sought to estimate the relative hazards of graft failure at different current ages, compared with patients between 20 and 24 years old. We evaluated 11 473 patients recorded in the Scientific Registry of Transplant Recipients who received a first transplant at <40 years old (1988-2013) and had at least 6 months of graft function. Time-dependent Cox models were used to estimate the association between current age (time-dependent) and failure risk, adjusted for time since transplant and other potential confounders. Failure was defined as death following graft failure or retransplant; observation was censored at death with graft function. There were 2567 failures. Crude age-specific graft failure rates were highest in 21-24 year olds (4.2 per 100 person-years). Compared to individuals with the same time since transplant, 21-24 year olds had significantly higher failure rates than all other age periods except 17-20 years (HR 0.92 [95%CI 0.77, 1.09]) and 25-29 years (0.86 [0.73, 1.03]). Among young first heart transplant recipients, graft failure risks are highest in the period from 17 to 29 years of age.

Effect of human leukocyte antigen-C and -DQ matching on pediatric heart transplant graft survival

BACKGROUND

A higher degree of human leukocyte antigen (HLA) matching at the A, B, and DR loci has been associated with improved long-term survival after pediatric heart transplantation in multiple International Society for Heart and Lung Transplantation registry reports. The aim of this study was to investigate the association of HLA matching at the C and DQ loci with pediatric graft survival.

METHODS

The United Network of Organ Sharing database was queried for isolated heart transplants that occurred from 1988 to 2012 with a recipient age of 17 or younger and at least 1 postoperative follow-up encounter. When HLA matching at the C or DQ loci were analyzed, only transplants with complete typing of donor and recipient at the respective loci were included. Transplants were divided into patients with at least 1 match at the C locus (C-match) vs no match (C-no), and at least 1 match at the DQ (DQ-match) locus vs no match (DQ-no). Primary outcome was graft loss. Univariate analysis was performed with the log-rank test. Cox regression analysis was performed with the following patient factors included in the model: recipient age, ischemic time; recipient on ventilator, extracorporeal membrane oxygenation, ventricular assist device, or inotropes at transplant; recipient serum bilirubin and creatinine closest to transplant, ratio of donor weight to recipient weight, underlying cardiac diagnosis, crossmatch results, transplant year, and HLA matching at the A, B, and DR loci.

RESULTS

Complete typing at the C locus occurred in 2,429 of 4,731 transplants (51%), and complete typing at the DQ locus occurred in 3,498 of 4,731 transplants (74%). Patient factors were similar in C-match and C-no, except for year of transplant (median year, 2007 [interquartile range, 1997-2010] vs year 2005 [interquartile range, 1996-2009], respectively; p = 0.03) and the degree of HLA matching at the A, B, and DR loci (high level of HLA matching in 11.9% vs 3%, respectively; p < 0.01). Matching at the C locus was not associated with a decreased risk of graft loss (median graft survival: 13.1 years [95% confidence interval {CI}, 11.5-14.8] in C-no vs 15.1 years [95% CI, 13.5-16.6) in C-match, p = 0.44 log-rank; hazard ratio, 0.93; 95% CI, 0.76-1.15; p = 0.52). DQ-match did not differ from DQ-no in any of the analyzed patient factors, except DQ-match was more likely to have high degree of matching at the A, B, and DR loci vs DQ-no (9.8% vs 3.2%, p < 0.01). Matching at the DQ locus was not associated with decreased risk of graft loss (median graft survival: DQ-no, 13.1 years [95% CI, 11.7-14.6) vs DQ-match, 13.0 years [95% CI, 11.4-14.6], p = 0.80, log-rank; hazard ratio, 0.95; 95% CI, 0.81-1.1; p = 0.51.

CONCLUSIONS

Complete typing at the C locus of both donor and recipient occurs less often then typing at the DQ locus. A higher degree of donor-recipient HLA matching at the C locus or the DQ locus appears not to confer any graft survival advantage.

The role of disparities and socioeconomic factors in access to kidney transplantation and its outcome

BACKGROUND

Research focused on identifying vulnerable populations and revealing specific risk factors for barriers along the pathway from ESRD to kidney transplantation has been mostly descriptive and the causes of existing disparities remain unclear. However, several socio-economic factors that are associated with the access to and the outcome of the kidney transplantation have been identified.

SUMMARY

While the presence of racial, gender, and geographic disparities is noted, we were interested mostly to describe potential socio-economic factors associated with and possibly responsible for the presence of such disparities. In this review we focused on five factors: education level, employment status, income, presence of substance addiction or abuse, and marital status. We describe the new method to quantify patients' socio-economic status and identify the group of high risk in terms of the transplant outcome, easily calculated social adaptability index, previously associated with clinical outcome in several patient populations including those with kidney transplant. At the end, based on literature analyzed we offer potential interventions that potentially can be used in order to reduce the degree of disparities.

CONCLUSION

Based on review of literature socio-economic factors are associated with and possibly responsible for healthcare disparities. Social adaptability index allows quantifying the degree of socio-economic status and identifying the group of high risk for inferior transplant outcome.

Association of human leukocyte antigen donor-recipient matching and pediatric heart transplant graft survival

BACKGROUND

The effect of donor-recipient human leukocyte antigen (HLA) matching on outcomes remains relatively unexplored in pediatric patients. The objective of this study was to investigate the effects of donor-recipient HLA matching on graft survival in pediatric heart transplantation.

METHODS AND RESULTS

The UNOS (United Network for Organ Sharing) database was queried for heart transplants occurring between October 31, 1987, and December 31, 2012, in a recipient aged ≤17 years with ≥1 postoperative follow-up visit. Retransplants were excluded. Transplants were divided into 3 donor-recipient matching groups: no HLA matches (HLA-no), 1 or 2 HLA matches (HLA-low), and 3 to 6 HLA matches (HLA-high). Primary outcome was graft loss. Four thousand four hundred seventy-one heart transplants met the study inclusion criteria. High degree of donor-recipient HLA matching occurred infrequently: HLA-high (n=269; 6%) versus HLA-low (n=2683; 60%) versus HLA-no (n=1495; 34%). There were no differences between HLA matching groups in the frequency of coronary vasculopathy (P=0.19) or rejection in the first post-transplant year (P=0.76). Improved graft survival was associated with a greater degree of HLA donor-recipient matching: HLA-high median survival, 17.1 (95% confidence interval, 14.0-20.2) years; HLA-low median survival, 14.2 (13.1-15.4) years; and HLA-no median survival, 12.1 (10.9-13.3 years) years; P<0.01, log-rank test. In Cox-regression analysis, HLA matching was independently associated with decreased graft loss: HLA-low versus HLA-no hazard ratio, 0.86 (95% confidence interval, 0.74-0.99), P=0.04; HLA-high versus HLA-no, 0.62 (95% confidence interval, 0.43-0.90), P<0.01.

CONCLUSIONS

Decreased graft loss in pediatric heart transplantation was associated with a higher degree of donor-recipient HLA matching, although a difference in the frequency of early rejection or development of coronary artery vasculopathy was not seen.

Racial and socioeconomic disparities in pediatric and young adult liver transplant outcomes

Racial and socioeconomic disparities exist in liver transplantation (LT) outcomes among adults, but little research exists for pediatric LT populations. We examined racial differences in graft survival and mortality within a retrospective cohort of pediatric and young adult LT recipients at a large children's transplant center in the Southeast between 1998 and 2011. The association between race/ethnicity and rates of graft failure and mortality was examined with Cox proportional hazards models that were adjusted for demographic and clinical factors as well as individual-level and census tract-level socioeconomic status (SES). Among the 208 LT recipients, 51.0% were white, 34.6% were black, and 14.4% were other race/ethnicity. Graft survival and patient survival were higher for whites versus minorities 1, 3, 5, and 10 years after transplantation. The 10-year graft survival rates were 84% [95% confidence interval (CI) = 76%-91%] for white patients, 60% (95% CI = 46%-74%) for black patients, and 49% (95% CI = 23%-77%) for other race/ethnicity patients. The 10-year patient survival rates were 92% (95% CI = 84%-96%), 65% (95% CI = 52%-79%), and 76% (95% CI = 54%-97%) for the white, black, and other race/ethnicity groups, respectively. In analyses adjusted for demographic, clinical, and socioeconomic characteristics, the rates of graft failure [black: hazard ratio (HR) = 2.59, 95% CI = 1.29-5.45; other: HR = 3.01, 95% CI = 1.23-7.35] and mortality (black: HR = 4.24, 95% CI = 1.54-11.69; other: HR = 3.09, 95% CI = 0.78-12.19) were higher for minority groups versus whites. In conclusion, at a large pediatric transplant center in the Southeastern United States, racial/ethnic disparities exist in pediatric and young adult LT outcomes that are not fully explained by measured SES and clinical factors.

Lower socioeconomic status is associated with worse outcomes after both listing and transplanting children with heart failure

The relationship between SES and outcomes surrounding pediatric cardiac transplantation is complex and influenced by recipient race. Broad-based studies of SES have not been performed. A retrospective review of all 5125 primary pediatric heart transplants performed in the United States between 2000 and 2011. Patients were stratified by SES based on zip code of residence and U.S. census data (low SES: 1637; mid-SES: 2253; high SES: 1235). Survival following listing and transplantation was compared across strata. Risk-adjusted long-term mortality on the waitlist was higher among low SES patients (hazard 1.32, CI 1.07-1.63). The relationship between SES and outcomes varied by race. Early risk-adjusted post-transplant outcomes were worst among high SES patients (10.8% vs. low SES: 8.9%, p < 0.05). The incidence of non-compliance was higher among low SES patients (p < 0.0001). Long-term risk-adjusted patient survival was poorer among low (hazard 1.41, CI 1.10-1.80) and mid-SES (1.29, 1.04-1.59) groups. Low SES is associated with worse outcomes on both the waitlist and late following transplantation. Higher SES patients had more complex transplants with higher early mortality. Further research should be directed at identifying and addressing underlying causal factors for these disparities.

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.

Factors associated with survival in patients who undergo peritoneal dialysis catheter placement following cardiac surgery

PURPOSE

Pediatric post-cardiac surgery patients are at risk for acute kidney injury and intraabdominal hypertension. The present study assesses indications and outcomes of postoperative peritoneal dialysis catheter (PDC) placement in this population.

METHODS

We retrospectively reviewed single-institution patients who underwent PDC placement post-cardiac surgery between 1999 and 2011 (n=55). Baseline, clinical course, and outcome data were recorded pre- and post-PDC. We used multivariable logistic and Cox analyses to assess factors associated with mortality.

RESULTS

In-hospital mortality of the study cohort was 67.3% (n=37). Peritoneal dialysis was performed in 21 patients (38.2%). Five patients (9.1%) experienced adverse events related to PDC placement. Greater post-PDC decreases in abdominal girth (adjusted odds ratio [OR]=2.43; P=0.02) and BUN (OR=1.06; P=0.04) were associated with survival. Additionally, preoperative ventilator independence (hazard ratio [HR]=1.18; P<0.01) and lower creatinine (HR=8.32; P<0.01), as well as greater post-PDC decrease in inotrope score (HR=1.33; P<0.02) were associated with survival.

CONCLUSIONS

In-hospital mortality of the study cohort was 67%. Less severe pre-PDC renal impairment, increased pre-PDC abdominal girth, and greater post-PDC improvement of abdominal girth, renal function, and inotrope requirements were associated with survival. Prospective trials are needed to assess appropriate indications and timing of PDC placement, with consideration of more aggressive treatment for intraabdominal hypertension.

Continuous-flow left ventricular assist device implantation as a bridge to transplantation or destination therapy: racial disparities in outcomes

BACKGROUND

There is a paucity of data assessing racial disparities in outcomes after left ventricular assist device (LVAD) implantation. This may be due to the relatively low percentage of African American (AA) patients at a given center. Given the high proportion of AAs in our patient population, we sought to evaluate outcomes of LVAD implantation in AAs vs Caucasians.

METHODS

We stratified 88 LVAD patients by AA or Caucasian race. Variables were compared using 2-sided t-tests, chi-square tests, Cox proportional hazards models, and log-rank tests to determine whether a difference existed between AAs and Caucasians and whether race was a significant independent predictor of outcome.

RESULTS

AAs represented 36.4% (32 of 88) of our LVAD patients. The two groups did not differ significantly in the incidence of hypertension, diabetes, or chronic renal insufficiency, reoperation rates, pre-operative body mass index, left ventricular ejection fraction, central venous pressure, pulmonary capillary wedge pressure, pulmonary artery pressure, or right ventricular function. Compared with Caucasians, AAs were significantly younger (48.6 vs 54.8 years, p = 0.019), and had a significantly higher mean body surface area (p = 0.009) and a higher rate of non-ischemic dilated cardiomyopathy (61% vs 39%, p = 0.008). No significant difference was found in 30-day (p = 0.12), 180-day (p = 0.166), or 360-day (p = 0.18) survival. Analysis by univariate Cox proportional hazard models (hazard ratio [95% confidence interval]) showed race was not an independent predictor of 30-day (4.5 [0.56-35.94], p = 0.157), 180-day (3.9 [0.48-31.95], p = 0.2), or 360-day survival (1.8 [0.6-5.71], p = 0.286). Age and pre-operative renal failure were the only independent predictors of survival at 30 days (1.1 [1.02-1.19], p = 0.019; 4.99 [1.24-20], p = 0.023, respectively), 180 days (1.09 [1-1.18], p = 0.041; 4.14 [0.99-17.39], p = 0.05), and 360 days (1.05 [1-1.1], p = 0.044; 2.52 [0.94-6.75], p = 0.05). Analysis by a multivariate logistic regression model showed age and chronic renal failure were no longer statistically significant for survival at 30, 180, and 360 days.

CONCLUSIONS

Although multiple studies have demonstrated that AAs experience worse outcomes after coronary artery bypass grafting, heart transplantation, and valve surgery, we did not find similar results in our LVAD population. More rigorous pre-operative LVAD workup, including an evaluation by a multidisciplinary team, along with more intense post-operative follow-up, may explain improved outcomes in AAs after LVAD implantation compared with other cardiac surgical procedures, although additional analysis is required.