Nonadherence is associated with late rejection in pediatric heart transplant recipients

Long-term outcomes for pediatric heart transplant recipients transitioning to adult care teams

BACKGROUND

There are limited data evaluating the success of a structured transition plan specifically for pediatric heart transplant (HT) recipients following their transfer of care to an adult specialist. We sought to identify risk factors for poor adherence, graft failure, and mortality following the transfer of care to adult HT care teams.

METHODS

We retrospectively reviewed all patients who underwent transition from the pediatric to adult HT program at our center between January 2011 and June 2021. Demographic characteristics, comorbid conditions, and psychosocial history were collected at the time of HT, the time of transition, and the most recent follow-up. Adverse events including mortality, graft rejection, infection, and renal function were also captured before and after the transition.

RESULTS

Seventy-two patients were identified (54.1% male, 54.2% Caucasian). Mean age at the time of transition was 23 years after a median of 11.6 years in the pediatric program. The use of calcineurin inhibitors was associated with reduced mortality (HR .04, 95% CI .0-.6, p = .015), while prior psychiatric hospitalization (HR 45.3, 95% CI, 6.144-333.9, p = .0001) was associated with increased mortality following transition. Medication nonadherence and young age at the time of transition were markers for high-risk individuals prior to the transition of care.

CONCLUSIONS

Transition of HT recipients from a pediatric program to an adult program occurs during a vulnerable time of emerging adulthood, and we have identified risk factors for mortality following transition. Development of a formalized transition plan with a large multidisciplinary team with focused attention on high-risk patients, including those with psychiatric comorbidities, may favorably influence outcomes.

Cardiac allograft vasculopathy and survival in pediatric heart transplant recipients transitioned to adult care

BACKGROUND

Cardiac allograft vasculopathy (CAV) is an important cause of mortality after pediatric heart transplantation (HT) but there is a paucity of data regarding its incidence and impact on survival in pediatric recipients transitioned to adult care.

METHODS

We conducted a retrospective review of consecutive pediatric HT patients from 1989 to 2017 at the Hospital for Sick Children who transitioned to adult care at ≥18 years at Toronto General Hospital. We evaluated the incidence of International Society of Heart and Lung Transplantation CAV grade ≥1 using competing risk models. We assessed the association between all-cause mortality and CAV using Cox proportional hazards and used Kaplan Meier methods to evaluate all-cause mortality stratified by CAV and transplant era (1989-2001, 2002-2017).

RESULTS

Ninety-six patients were transitioned to adult care by January 2022, of which 53 underwent repeat coronary angiography as adults. CAV was newly diagnosed in 49% patients after transition to adult care. The overall incidence of CAV was 3.9 cases per 100 person-years. There was no difference in the adjusted incidence of CAV according to transplant era (subdistribution hazard ratios = 1.17, 95% confidence interval (CI) 0.54-2.66). CAV was associated with a higher risk of death in the early era (hazard ratio (HR) 10.29, 95% CI 2.16-49.96), but not in the recent era (HR 1.61, 95% 0.35-7.47).

CONCLUSIONS

There is a role for continued CAV surveillance after the transition to adult care. The implications of diagnosing CAV after the transition to adult care require further study, particularly because the risk of death in pediatric HT recipients diagnosed with CAV in the more recent era may be attenuated compared to the earlier HT era.

A Systematic Review of Adherence to Immunosuppression among Pediatric Heart Transplant Patients

After pediatric heart transplant, commitment to lifelong immunosuppression is crucial to maintaining graft health. However, a review of the current literature surrounding adherence to immunosuppression in pediatric heart transplant patients is lacking. This systematic review aims to summarize the current landscape of adherence to immunosuppression in pediatric heart transplant patients. We conducted searches in PubMed MEDLINE, Embase, CENTRAL register of Controlled Trials (Wiley), and Scopus, from inception to March 2020. Studies were eligible if they outlined an aspect of adherence to immunosuppression and the measurement of adherence was performed with an objective or otherwise validated measure of adherence (e.g., drug levels, adherence questionnaires). The titles/abstracts of 880 articles were reviewed. After initial screening, 106 articles underwent full text review. As such, 14 articles were included in the final review. Baseline adherence estimates varied greatly, with most values between 40% and 70%. Nonadherence to immunosuppression is associated with worse outcomes (rejection, hospitalization, mortality), impaired quality of life, and mental health concerns in pediatric heart transplant patients. As nonadherence to immunosuppression is common and associated with worse outcomes, there is a need for further development and evaluation of interventions in this space.

A primer for managing cardiac transplant patients in the emergency department setting

BACKGROUND

Cardiac transplant is an effective long-term management option for several severe cardiac diseases. These cardiac transplant patients may present to the emergency department with a range of issues involving the cardiac transplantation, including complications due to their transplant as well as altered presentations of disease resulting from their transplant.

OBJECTIVE

This narrative review provides a focused guide to the evaluation and management of patients with cardiac transplantation and its complications.

DISCUSSION

Cardiac transplant is an effective therapy for end-stage heart failure. A transplanted heart varies both anatomically and physiologically from a native heart. Several significant complications may occur. Graft failure, rejection, and infection are common causes of morbidity and mortality within the first year of transplant. As these patients are on significant immunosuppressive medication regimens, they are at risk of infection, but inadequate immunosuppression increases the risk of acute rejection. A variety of dysrhythmias such as atrial fibrillation and ventricular dysrhythmias may occur. These patients are also at risk of acute coronary syndrome, cardiac allograft vasculopathy, and medication adverse events. Importantly, patients with acute coronary syndrome can have an altered presentation with the so-called "painless" myocardial infarction. Consultation with the transplant physician is recommended, if available, for these patients to assist in evaluation and management.

CONCLUSIONS

An understanding of the presentations and various complications that may affect patients with cardiac transplant will assist emergency clinicians in the care of these patients.

Prospective single-centre clinical observational study on electronically monitored medication non-adherence, its psychosocial risk factors and lifestyle behaviours after heart transplantation: a study protocol

INTRODUCTION

In heart transplant recipients (HTRs), non-adherence (NA) to immunosuppressive (IS) medication and to recommended lifestyle behaviours are a common phenomenon and associated with higher risk of allograft rejection, organ loss and mortality. Risk factors for NA are highly diverse and still insufficiently researched. Precise measures of NA and an accurate understanding of its aetiology are of undisputable importance to detect patients at risk and intervene accordingly. The aim of this study is to assess the accuracy and concordance of different measures for NA as well as to determine potential risk factors.

METHODS AND ANALYSIS

This is a single-centre prospective observational trial. HTRs who are at least aged 18 are no less than 6 months post-transplant and receive tacrolimus (Prograf or Advagraf), cyclosporine (Sandimmun) or everolimus (Certican) as their prescribed IS medication are eligible for participation. We only include patients during the phase of medication implementation. At study enrolment, we assess depression, health-related quality of life, self-efficacy, social support, attachment, experiences and attitudes towards IS medication, emotional responses after transplantation, satisfaction with information about IS medication and perceptions and beliefs about medications. We further ask patients to rate their lifestyle behaviours concerning alcohol, smoking, diet, physical activity, sun protection and appointment keeping via questionnaires. Three different measurement methods for NA are applied at T0: self-reports, physician's estimates and IS trough levels. NA is monitored prospectively using an electronic multicompartment pillbox (MEMS, VAICA) over a 3-month period. Meanwhile, participants receive phone calls every second week to obtain additional self-reports, resulting in a total of seven measurement points.

ETHICS AND DISSEMINATION

The study was approved by the Clinical Ethics Committee of the University Hospital Erlangen (Friedrich-Alexander-University, Erlangen-Nürnberg). Written informed consent is attained from all participants. The results of this study will be published in peer-reviewed journals and presented at conferences.

TRIAL REGISTRATION NUMBER

DRKS00020496.

Assessment of rejection risk following subtherapeutic calcineurin inhibitor levels after pediatric heart transplantation

CNIs are the mainstay of immunosuppressive therapy after pediatric HTx. While regular laboratory surveillance is performed to ensure blood levels are within targeted range, the risk of acute rejection associated with subtherapeutic CNI levels has never been quantified. This is a retrospective single-center review of 8413 CNI trough levels in 138 pediatric HTx recipients who survived >1 year after HTx. Subtherapeutic CNI levels were defined as <50% of the lower limit of target range. The risk of acute, late (>12 months post-transplant) rejection following recipients' subtherapeutic CNI levels was assessed using time-varying multivariable Cox proportional hazards analysis. We found that 79 of 138 recipients (57%) had at least one subtherapeutic CNI level on routine surveillance laboratories during a mean follow-up of 5.5 ± 3.6 years. Following an episode of subtherapeutic levels, 17 recipients (22%) had biopsy-proven rejection within the next 3 months; the majority (9/17) within the first 2 weeks. After presenting with subtherapeutic CNI levels, recipients incurred a 6.1 times increased risk of acute rejection in the following 3 months (HR = 6.11 [2.41, 15.51], P = <.001). Age at HTx, HLA sensitization, or positive crossmatch were not associated with acute late rejection, but rejection in the first post-transplant year was (HR 2.61 [1.27, 5.35], P = .009). Thus, maintaining therapeutic CNI levels is the most important factor in preventing acute rejection in recipients who are >12 months after pediatric HTx. Recipients who present with subtherapeutic CNI levels on surveillance monitoring are 6.1 times more likely to develop rejection in the following 3 months.

Pediatric Heart Transplantation: Transitioning to Adult Care (TRANSIT): Feasibility of a Pilot Randomized Controlled Trial

BACKGROUND

Young-adult heart transplant recipients transferring to adult care are at risk for poor health outcomes. We conducted a pilot randomized controlled trial to determine the feasibility of and to test a transition intervention for young adults who underwent heart transplantation as children and then transferred to adult care.

METHODS

Participants were randomized to the transition intervention (4 months long, focused on heart-transplant knowledge, self-care, self-advocacy, and social support) or usual care. Self-report questionnaires and medical records data were collected at baseline and 3 and 6 months after the initial adult clinic visit. Longitudinal analyses comparing outcomes over time were performed using generalized estimating equations and linear mixed models.

RESULTS

Transfer to adult care was successful and feasible (ie, excellent participation rates). The average patient standard deviation of mean tacrolimus levels was similar over time in both study arms and < 2.5, indicating adequate adherence. There were no between-group or within-group differences in percentage of tacrolimus bioassays within target range (> 50%). Average overall adherence to treatment was similarly good in both groups. Rates of appointment keeping through 6 months after transfer declined over time in both groups.

CONCLUSIONS

The feasibility of the study was demonstrated. Our transition intervention did not improve outcomes.

Applying the Self-determination Theory to Health-related Quality of Life for Adolescents with Congenital Heart Disease

PURPOSE

The purpose of this study is to examine the relationship among the three innate needs of Self-Determination Theory (SDT), self-management of care and adherence to treatment, and the relationship to health-related quality of life (HRQOL) for adolescents with congenital heart disease (CHD).

DESIGN AND METHODS

A non-experimental, cross-sectional, correlational design was conducted in a sample of 92 participants with CHD, ages 13 to 18 years. For data analysis, Pearson's correlations were used to explore associations between variables, and the hypotheses were tested using multiple linear regression.

RESULTS

Demographic and clinical data were collected: 15 ± 1.6 yrs; 59% male; 65% White; 43% mild CHD; 25% severe CHD. After controlling for covariates, regression analyses revealed relatedness (β = 0.64) and competence (β = 0.79) contributed significant variance to HRQOL, R² = 0.56, p < .001; however, autonomy and self-management of care and treatment adherence did not contribute significant variance to HRQOL.

CONCLUSIONS

This study found that relatedness and competence were significantly associated with HRQOL in adolescents with CHD; however, autonomy and self-management of care and adherence to treatment were not. These findings demonstrate the importance of further examining relatedness and competence in adolescents with CHD.

PRACTICE IMPLICATIONS

Nursing care should focus on the improvement of social support systems and interventions to increase self-efficacy for adolescents with CHD.

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.

Psychosocial predictors of medication non-adherence in pediatric organ transplantation: A systematic review

Adherence to immunosuppressant medication is critical to health and quality-of-life outcomes for children who have received a solid organ transplant. Research on the psychological and social predictors of medication adherence is essential to the advancement of pretransplant assessments and transplant psychosocial services. Despite the importance of identifying risk factors, the literature remains limited regarding psychosocial predictors of non-adherence. A systematic search was conducted to identify studies of the psychosocial predictors of post-transplant medication non-adherence in pediatric solid organ transplantation. From 1363 studies identified in searches of empirical literature, a final sample consisted of 54 publications representing 49 unique studies. Findings regarding psychosocial predictors were inconsistent with non-adherence associated largely with adolescence, racial/ethnic minority status, and presence of mental health issues. Familial predictors of non-adherence problems included single-parent households, lower socioeconomic status, lower family cohesion, presence of family conflict, and poor family communication. Several studies reported an association between non-adherence and social pressures (eg, peer social interaction, wanting to feel normal) among adolescent transplant recipients. While significant methodological and substantive gaps remain in this body of knowledge, this review synthesizes current evidence for assessment for transplant clinicians and researchers.

Psychosocial predictors of medication adherence in pediatric heart and lung organ transplantation

Few studies have identified the psychosocial characteristics of those children and their families associated with future non-adherence to immunosuppressive medications following a heart or lung transplant. UNOS data and medical records information were used to test the association between patient and family psychosocial characteristics and medication adherence. Medication adherence outcomes were obtained using the physician assessments in the UNOS data and measured through patient-level standard deviation scores of immunosuppressive medication blood levels. Complete data were collected on 105 pediatric heart and lung transplant recipients and their families. Multivariate, stepwise analyses were conducted with each adherence outcome. Physician reports of adherence were associated with age of the child at transplantation, parental education, two-parent families, significant psychosocial problems, and the pretransplant life support status of the child. The resulting model (χ² =28.146, df=5, P<.001) explained approximately 39.5% of the variance in physician reports of adherence (Nagelkerke r² =.395). Blood level standard deviation scores were predicted by age at transplant (F=5.624, P=.02, r² =.05). Results point to the difficulties experienced by children and families when undergoing a heart or lung transplantation. Efforts to develop standardized and evidence-based pretransplant psychosocial assessments in pediatric populations are suggested, especially those surrounding familial risk factors.

Reported Nonadherence to Immunosuppressive Medication in Young Adults After Heart Transplantation: A Retrospective Analysis of a National Registry

BACKGROUND

Young adult heart transplantation (HTx) recipients experience high mortality risk attributed to increased nonadherence to immunosuppressive medication in this age window. This study sought to test whether a high-risk age window in HTx recipients persisted in the absence of reported nonadherence.

METHODS

Heart transplantation recipients aged 2 to 40 years, transplanted between October 1999 and January 2007, were identified in the United Network for Organ Sharing database. Multivariable survival analysis was used to estimate influences of age at transplantation and attained posttransplant age on mortality hazard among patients stratified by center report of nonadherence to immunosuppression that compromised recovery.

RESULTS

Three thousand eighty-one HTx recipients were included, with univariate analysis demonstrating peak hazards of mortality and reported nonadherence among 567 patients transplanted between ages 17 and 24 years. Multivariable analysis adjusting for reported nonadherence demonstrated lower mortality among patients transplanted at younger (hazards ratio, 0.813; 95% confidence interval, 0.663-0.997; P = 0.047) or older (hazards ratio, 0.835; 95% confidence interval, 0.701-0.994; P = 0.042) ages. Peak mortality hazard at ages 17 to 24 years was confirmed in the subgroup of patients with no nonadherence reported during follow-up. This result was replicated using attained age after HTx as the time metric, with younger and older ages predicting improved survival in the absence of reported nonadherence.

CONCLUSIONS

Late adolescence and young adulthood coincide with greater mortality hazard and greater chances of nonadherence to immunosuppressive medication after HTx, but the elevation of mortality hazard in this age range persists in the absence of reported nonadherence. Other causes of the high-risk age window for post-HTx mortality should be demonstrated to identify opportunities for intervention.

Patient-reported non-adherence and immunosuppressant trough levels are associated with rejection after renal transplantation

Background

Different measures of non-adherence to immunosuppressant (IS) medication have been found to be associated with rejection episodes after successful transplantation. The aim of the current study was to investigate whether graft rejection after renal transplantation is associated with patient-reported IS medication non-adherence and IS trough level variables (IS trough level variability and percentage of sub-therapeutic IS trough levels).

Methods

Patient-reported non-adherence, IS trough level variability, percentage of sub-therapeutic IS trough levels, and acute biopsy-proven late allograft rejections were assessed in 267 adult renal transplant recipients who were ≥12 months post-transplantation.

Results

The rate of rejection was 13.5%. IS trough level variability, percentage of sub-therapeutic IS trough levels as well as patient-reported non-adherence were all significantly and positively associated with rejection, but not with each other. Logistic regression analyses revealed that only the percentage of sub-therapeutic IS trough levels and age at transplantation remained significantly associated with rejection.

Conclusions

Particularly, the percentage of sub-therapeutic IS trough levels is associated with acute rejections after kidney transplantation whereas IS trough level variability and patient-reported non-adherence seem to be of subordinate importance. Patient-reported non-adherence and IS trough level variables were not correlated; thus, non-adherence should always be measured in a multi-methodological approach. Further research concerning the best combination of non-adherence measures is needed.

Transplantation

Despite improvement in median life expectancy and overall health, some children with cystic fibrosis (CF) progress to end-stage lung or liver disease and become candidates for transplant. Transplants for children with CF hold the promise to extend and improve the quality of life, but barriers to successful long-term outcomes include shortage of suitable donor organs; potential complications from the surgical procedure and immunosuppressants; risk of rejection and infection; and the need for lifelong, strict adherence to a complex medical regimen. This article reviews the indications and complications of lung and liver transplantation in children with CF.

Medication Adherence after Heart Transplantation: Adolescents and Their Issues

Context

Medication nonadherence among adolescent heart transplant recipients can have overwhelming negative consequences including rejection and mortality. Because of issues specific to adolescents such as peer pressure, risk taking, independence, self-image, and self-esteem, they are a population susceptible to nonadherence. Adherence may be associated with a supportive environment, fewer physical and cosmetic side effects, and a sufficient knowledge of therapies. Adherence also may be related to regimens with fewer medications, predominantly fewer immunosuppressive drugs.

Objective

To examine the differences in motivation between adolescents who are more adherent and those who are less adherent to their medication regimen following transplant surgery.

Design

A descriptive design and mixed methodology, including a modified written survey, the Frazier Noncompliance Inventory; a self-report measure of overall medication adherence; and an interview designed by the investigator. Interview questions were reviewed for content validity by nurse clinicians and researchers.

Setting

A heart transplant follow-up clinic in the southeastern United States.

Results

Findings for 2 participants revealed striking contrasts in adolescent issues and factors affecting adherence. These findings are presented in a case comparison. Data show that a supportive environment and knowledge of medications were significant in increasing self-responsibility and adherence in adolescent transplant recipients. Also, experiencing rejection early in treatment because of less adherence led to increased adherence for fear of further rejections or death.

Monitoring drug adherence

TOPIC

Medication nonadherence is prevalent in transplant recipients and is a major reason for graft loss. The present review discusses the measurement of adherence in transplant recipients and strategies to improve adherence. SOURCES REVIEWED: Since adherence research is not confined to transplant recipients, our literature review included studies relevant to transplant recipients as well as adherence to medical recommendations more generally. We reviewed manuscripts in the English language indexed in PubMed Central, as well as ancillary sources of information such as textbook chapters that are not indexed.

CONCLUSION

There is no consensus in the literature about an optimal way to monitor adherence, nor is there agreement about a preferred management strategy. Until definitive studies demonstrate the effectiveness of intervention strategies, knowledge of the monitoring as well as intervention methods that are described in this review is expected to give practitioners the initial tools to deal with nonadherence as an important aspect of patient care.

Heart Failure in Children

Heart failure (HF) in children differs from that in adults in many respects. The causes and clinical presentations may differ considerably among children of different age groups and between children and adults. The time of onset of HF holds the key to the etiological diagnosis. Clinical presentation of HF in younger children can be nonspecific requiring heightened degree of suspicion. The overall outcome with HF is better in children than in adults as HF in children is commonly due to structural heart disease and reversible conditions which are amenable to therapy. The principles of management include treatment of the cause, correction of any precipitating event, and treatment of systemic or pulmonary congestion. Though HF in adults has been the subject of extensive research and generation of evidence-based guidelines, there is a scarcity of evidence base in pediatric HF.

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.

Population pharmacokinetics and pharmacogenetics of once daily tacrolimus formulation in stable liver transplant recipients

Purpose

The once daily formulation of tacrolimus is an important immunosuppressive drug. Interpatient variability in metabolism has been related to genetic variation in CYP3A4 and CYP3A5. However, in liver transplantation, both donor and recipient genotypes may affect pharmacokinetics. The primary objective of this study was to investigate the effect of CYP3A4*22 and CYP3A5*3 of both donor and recipient on once daily tacrolimus pharmacokinetics. The secondary objective was to develop a limited sampling model able to accurately predict exposure.

Methods

Stable liver transplant patients receiving once daily tacrolimus (N = 66) were included. Population pharmacokinetic analysis was performed with patients of whom DNA was available (N = 49), and demographic factors, CYP3A4*22 and CYP3A5*3, were tested as covariates. Moreover, a limited sampling model was developed using data of 66 patients.

Results

Pharmacokinetics was best described by a two-compartment model with delayed absorption. CYP3A5*1 carrying recipients engrafted with a CYP3A5*1 carrying liver had an average 1.7-fold higher clearance compared to non-carriers. CYP3A5*1 carrying recipients engrafted with a CYP3A5*1 non-carrying liver or vice versa showed an average 1.3-fold higher clearance compared with non-carriers. CYP3A4*22 was not significantly associated with once daily tacrolimus pharmacokinetics. Using 0, 2, and 3 h postdose as limited sampling model resulted in significantly improved prediction of tacrolimus exposure compared with trough concentration.

Conclusions

Both donor and recipient CYP3A5 genotype significantly influences tacrolimus once daily pharmacokinetics. In contrast, CYP3A4*22 appears not suitable as biomarker. The developed limited sampling model can be used to accurately estimate tacrolimus once daily exposure.

Electronic supplementary material

The online version of this article (doi:10.1007/s00228-015-1963-3) contains supplementary material, which is available to authorized users.

Late rejection occurred in recipients who experienced acute cellular rejection within the first year after heart transplantation

Serial endomyocardial biopsies (EMBs) are scheduled even several years after heart transplantation (HTx) to monitor for late rejection (LR). However, repeated EMBs are associated with an increased risk for fatal complications and decrease the quality of life of the recipient. We retrospectively analyzed clinical data from 42 adult recipients who had received HTx and were followed > 1 year at the University of Tokyo Hospital. Five recipients experienced LR at 1130 ± 157 days after HTx, and all 5 had experienced acute cellular rejection (ACR) with ISHLT grade ≥ 2R within the first year, which was treated with methylprednisolone pulse therapy (sensitivity, 1.000; specificity, 0.7027). Logistic regression analyses demonstrated that positive panel reactive antibody (PRA) was the only significant predictor for LR among all parameters at 1 year after HTx (P = 0.020, odds ratio 24.00). Among the 5 recipients with LR, LR occurred earlier in the two PRA positive recipients than in those with a negative PRA (981 ± 12 versus 1230 ± 110 days, P = 0.042). Among the perioperative parameters, gender mismatch [n = 13 (31%)] was the only significant predictor for ACR within the first year in logistic regression analyses (P = 0.042, odds ratio 4.200). In conclusion, the current schedule of serial EMBs should perhaps be reconsidered for recipients without any history of ACR within the first year due to their lower risk of LR.

Pediatric heart transplantation-indications and outcomes in the current era

Pediatric heart transplantation (HTx) remains an important treatment option in the care of children with end-stage heart disease, whether it is secondary to cardiomyopathy or congenital heart disease (CHD). As surgical outcomes for CHD have improved, the indications for pediatric HTx have had to be dynamic, not only for children with CHD but also for the growing population of adults with CHD. As the field of pediatric HTx has evolved, the outcomes for children undergoing HTx have improved. This is undoubtedly due to the continued research efforts of both single-center studies, as well as research collaboratives such as the International Society for Heart and Lung Transplantation (ISHLT) and the Pediatric Heart Transplant Study (PHTS) group. Research collaboratives are increasingly important in pediatric HTx as single center studies for a limited patient population may not elicit strong enough evidence for practice evolution. Similarly, complications that limit the long term graft survival may occur in a minority of patients thus pooled experience is essential. This review focuses on the indications and outcomes for pediatric HTx, with a special emphasis on studies generated by these research collaboratives.

Pediatric heart transplantation-indications and outcomes in the current era

Pediatric heart transplantation (HTx) remains an important treatment option in the care of children with end-stage heart disease, whether it is secondary to cardiomyopathy or congenital heart disease (CHD). As surgical outcomes for CHD have improved, the indications for pediatric HTx have had to be dynamic, not only for children with CHD but also for the growing population of adults with CHD. As the field of pediatric HTx has evolved, the outcomes for children undergoing HTx have improved. This is undoubtedly due to the continued research efforts of both single-center studies, as well as research collaboratives such as the International Society for Heart and Lung Transplantation (ISHLT) and the Pediatric Heart Transplant Study (PHTS) group. Research collaboratives are increasingly important in pediatric HTx as single center studies for a limited patient population may not elicit strong enough evidence for practice evolution. Similarly, complications that limit the long term graft survival may occur in a minority of patients thus pooled experience is essential. This review focuses on the indications and outcomes for pediatric HTx, with a special emphasis on studies generated by these research collaboratives.

Adolescent age and heart transplantation outcomes in myocarditis or congenital heart disease

BACKGROUND

Adolescents often fare poorly after heart transplantation. However, whether the effect of age varies according to the etiology of heart failure is unknown. We tested the hypothesis that age-related heart transplantation outcomes are different in patients with myocarditis and congenital heart disease (CHD).

METHODS

A retrospective analysis of the United Network of Organ Sharing database was performed for patients with myocarditis (n = 709) and CHD (n = 1,631) undergoing heart transplantation from 1987 to 2011. The effect of age on graft survival was assessed. Age was categorized as children (6-12 years), adolescents (13-18 years), younger adults (19-30 years), and older adults (31-50 years).

RESULTS

For myocarditis, the median graft survival for adolescents was 6.9 years (95% confidence interval [CI], 5.6-9.6), which was significantly lower than other age groups (children: 14.1 [95% CI, 9.8-10.9] years, p = 0.004; younger adults: 11.8 [95% CI, 8.3-15.2] years, p = 0.172; older adults: 12.0 years [95% CI, 10.0-14.3 years], p = 0.033). For CHD, the median graft survival for adolescents was 7.4 years (95% CI, 6.8-8.6), which was not significantly different from other age groups (children: 9.0 [95% CI, 7.9-11.0] years, p = 0.737; younger adults: 11.2 [95% CI, 8.6-13.3] years, p = 0.744; older adults: 11.6 [95% CI, 9.2-15.3] years, p = 0.608). Multivariable analysis showed adolescent age was independently associated with worse graft survival for patients with myocarditis but not for CHD.

CONCLUSIONS

Adolescents with myocarditis have significantly worse graft survival after heart transplantation, but adolescents with CHD have similar outcomes to other patients with CHD. Further study is needed to improve outcomes in this vulnerable population.

Impact of medication non-adherence on survival after pediatric heart transplantation in the U.S.A

BACKGROUND

Medication non-adherence (NA) can result in life-threatening illness in children after solid-organ transplantation. Little is known about the incidence, risk factors and outcomes of NA in large numbers of pediatric heart transplant (HT) recipients.

METHODS

Organ Procurement Transplant Network (OPTN) data were used to identify all children <18 years of age in the U.S.A. who underwent HT from October 1999 to January 2007. Cox proportional hazards analysis was used to identify risk factors for NA and the effect on graft survival.

RESULTS

Of 2,070 pediatric heart transplants performed the median age at transplant was 6 years (interquartile range [IQR] 0 to 13 years); 40% had congenital heart disease (CHD), 7% were re-transplants, 42% were non-white and 43% had Medicaid insurance. Overall, 186 (9%) children had a report of NA at a median age of 15 years with more than two-thirds of NA episodes occurring after 12 years of age. Factors independently associated with NA were: adolescent age at transplant (hazard ratio [HR] 7.0, 95% confidence interval [CI] 4.1 to 12, compared with infants); black race (HR 2.3, 95% CI 1.7 to 3.3, compared with white); Medicaid insurance (HR 2.0, 95% CI 1.5 to 2.7, compared with non-Medicaid insurance); and ventilator or ventricular assist device (VAD) support at transplant. The risk of mortality conditional upon report of NA was 26% at 1 year and 33% at 2 years.

CONCLUSIONS

Medication NA is an important problem in pediatric HT recipients and is associated with high mortality. Adolescent age, black race, Medicaid insurance and invasive hemodynamic support at transplant were associated with NA, whereas time on the wait list and gender were not. Targeted interventions among at-risk populations may be warranted.

Essential Components of Transition to Adult Transplant Services: The Transplant Coordinators' Perspective

Context

Medical and surgical advancements have resulted in improved long-term survival of pediatric liver transplant recipients. As pediatric patients approach school age and adolescence, transplant centers are challenged to facilitate the process of transitioning from pediatric to adult centers.

Objective

To describe pediatric and adult liver transplant coordinators' perspective regarding practice for transitioning patients to adult-oriented transplant centers.

Design

Descriptive

Setting

Pediatric and adult liver transplant coordinators associated with Studies of Pediatric Liver Transplantation.

Participants

A total of 35 pediatric liver transplant coordinators and 24 adult liver transplant coordinators completed the survey.

Method

Investigator-developed survey to identify current practice for transition process and actual transfer of a patient from pediatric to adult care.

Results

Transplant coordinators play an integral role in the transition process, and study results highlight what experienced coordinators believe are important considerations for a successful transition process. Results also highlight the importance of communication and partnership between the pediatric and adult programs.

How ready are they? Parents of pediatric solid organ transplant recipients and the transition from hospital to home following transplant

Poor discharge transition is evidence of a gap between evidence-based practices and current health care delivery. Pediatric SOT recipients are a vulnerable population at risk of complications during the discharge transition. The aim of this study was to investigate factors associated with the transition care from hospital to home. We studied the transition experience of parents of heart, liver, or kidney recipients to identify opportunities for improvement in discharge and post-discharge care processes and outcomes. Thirty-seven parents from three different pediatric transplant centers completed questionnaires on the day of hospital discharge and three wk following hospital discharge. Care coordination was associated with readiness for hospital discharge. Readiness for hospital discharge was subsequently associated with post-discharge coping difficulty, adherence difficulty with medical follow-up, and family impact. Identifying parents who are not ready to go home provides an opportunity to offer additional support services so parents can effectively manage their child's recovery and continuing care at home.

Psychosocial implications during adolescence for infant heart transplant recipients

BACKGROUND & OBJECTIVES

As more heart transplant recipients survive into late adolescence, research addressing long-term psychosocial and neurodevelopmental outcomes is imperative. The limited literature available suggests risk for psychosocial difficulties and lower cognitive, academic, and neuropsychological functioning. This paper reviews topic-related literature and provides preliminary data examining psychosocial and neuropsychological functioning of adolescents who received their heart transplant during infancy.

METHOD

This paper offers a literature review AND presents preliminary data from studies conducted through Loma Linda University Children's Hospital (LLUCH). Study one examined psychosocial functioning and quality of life of adolescent infant heart transplant recipients. In study two, cognitive, academic, and neuropsychological data were analyzed.

RESULTS

Study 1: Overall psychosocial functioning fell in the Average range, however, a significant percentage of participants presented with difficulties on one or more of the psychosocial domains. Quality of life was also within normal limits, though concerns with general health and bodily discomfort were noted. Study 2: Cognitive functioning was assessed to be Below Average, with 43-62% of the participants demonstrating significant impairments. Neuropsychological functioning yielded significant weakness on language functioning, and mild weakness on visual-motor integration and executive functioning.

CONCLUSION

While the majority of the participants demonstrate psychosocial resiliency, a subgroup present with difficulties suggesting the need for intervention. Cognitive/neuropsychological functioning suggests poorer functioning with patterns similar to other high-risk pediatric populations. These results are preliminary and further research on long-term psychosocial and neuropsychological development of pediatric heart transplant recipients is needed to better understand and ameliorate developmental trajectories.

Inter-rater reliability of the Pediatric Transplant Rating Instrument (P-TRI): challenges to reliably identifying adherence risk factors during pediatric pre-transplant evaluations

The purpose of this study was to assess the inter-rater reliability of the P-TRI, a 17-item instrument developed to identify risk factors associated with poor treatment adherence in pediatric solid organ transplant candidates. Because factors influencing treatment adherence may vary with age, the 89 subject samples were divided into pre-adolescent (0-11 yr) and adolescent (12-19 yr) groups. Each subject received two independent P-TRI ratings based on pretransplant psychosocial assessments separately conducted by a PSYC and a SWTC. Inter-rater reliability was assessed using the delta statistic. Overall, agreement was higher in the pre-adolescent group, with delta>0.70 for five items and delta<0.30 for two items. For the adolescent group, one item had a delta>0.70 and seven items had a delta<0.30. Overall, PSYC P-TRI ratings indicated fewer areas of concern on items assessing family dynamics compared with SWTC P-TRI ratings, whereas the reverse was true for items related to psychiatric history. Results highlight the challenges of conducting a reliable pretransplant assessment of adherence-related risk factors and suggest the need for revisions to the P-TRI prior to its use in clinical practice.

Variability in tacrolimus blood levels increases the risk of late rejection and graft loss after solid organ transplantation in older children

  Late graft rejection impairs the long-term function of organ transplants in children. Previous studies suggest patients with wide variation in tacrolimus levels may have higher rates of late kidney and liver graft rejection. The reproducibility of this finding and impact on graft and recipient survival have not been reported. We investigated factors associated with late rejection > 6 months post-transplant in 144 heart, kidney, liver, and lung transplant recipients (ages 8-18, ≥ 1-yr survivors, receiving tacrolimus-based immunosuppression), comparing late rejectors (n = 61, 42%) to non-rejectors (no rejection > 6 months); groups had similar mean tacrolimus concentrations ≤ 6 months post-transplant. For all organ types, increased standard deviation in intrapatient tacrolimus blood levels was an independent risk factor for late rejection (OR 1.6 [CI 1.1-2.1]; p = 0.02). Each 1-point increase in s.d. > 2 of tacrolimus level > 6 months post-transplant associated with 1.58 increase in hazard of graft loss (p = 0.003). Graft survival (conditional on one-yr survival) was significantly better for those with s.d. < 2 at > 6 months post-transplant: 98% at three and five yr, versus 88%, 70%, at three and five yr, in patients with s.d. > 2 (p = 0.003). In conclusion, high s.d. in serial tacrolimus concentrations associated with increased risk of late rejection and graft loss in pediatric organ transplant recipients, providing opportunities for screening and interventions.

Heart transplantation for heart failure in children

Heart transplantation has become standard therapy for end-stage heart failure in children with cardiomyopathy as well as complex congenital heart disease, and has a significant effect on survival and quality of life. The indications for listing and referral for transplantation are outlined. Evaluation for heart transplantation is discussed, including full pretransplant assessment. ABO incompatible listing and HLA sensitization are discussed, and listing algorithms are outlined for different countries.

Decline in rejection in the first year after pediatric cardiac transplantation: a multi-institutional study

BACKGROUND

Rejection is a major cause of morbidity and mortality after pediatric heart transplantation (HTx). Survival after pediatric HTx has improved over time, but whether there has been an era-related improvement in the occurrence of allograft rejection is unknown.

METHODS

The Pediatric Heart Transplant Study (PHTS) database was queried for patients who underwent HTx from January 1993 to December 2005 to determine the incidence of rejection and identify factors associated with the first episode of rejection in the first year after HTx.

RESULTS

Data were reviewed in 1,852 patients from 36 centers. The incidence of rejection declined over 13 years at a rate of -2.58 +/- 0.41 (p < 0.001) from approximately 60% to 40% (p < 0.001). The mean number of episodes of rejection also significantly fell at a rate of -0.05 +/- 0.01 per patient/year from 1.19 to 0.66 (p < 0.001). The incidence of rejection with hemodynamic compromise and death from rejection did not change. Multivariate analysis for the risk of a first rejection episode demonstrated decreased risk of rejection with later year of HTx (odds ratio [OR], 0.88; 95% confidence interval [CI], 0.85-0.91; p < 0.001) and use of mechanical support (OR, 0.65; 95% CI, 0.42-0.99; p = 0.046). Increased risk of rejection was associated with positive donor-specific crossmatch (OR, 1.85; 95% CI, 1.18-2.88; p = 0.007) and older recipient age (OR, 1.05; 95% CI, 1.02-1.07; p < 0.001).

CONCLUSIONS

Although the overall incidence and prevalence of rejection has substantially decreased over time in pediatric HTx recipients in the first year after HTx, the rate of rejection with hemodynamic compromise or death from rejection remains unchanged.

Adherence to treatment among children with cardiac disease

OBJECTIVE

Our purpose was to review the literature with respect to issues of adherence to treatment among children with congenital and acquired cardiac disease.

MATERIALS AND METHODS

Databases used for this review included MEDLINE, Pub Med's Single Citation Manager, Cochrane Library, Cochrane Central Register of Controlled Trials, Scopus, and Google Scholar. We did not use any restrictions on date when locating peer-reviewed articles published worldwide through December of 2008.

RESULTS

There exists a lack of published research regarding adherence to medical treatment for children with cardiac conditions. Of the few published studies, rates of adherence for children with congenital and acquired cardiac disease ranged from a high of 96% for an in-patient exercise programme, to a low of 33% among those who made all of their medical appointments. Risk factors for nonadherence included older age, one as opposed to two parents in the home, lack of emotional availability of parents, smoking, sedentary lifestyle, use of illicit drugs, presence of tattoos, and multiple body piercings. Clinical outcomes associated with non adherence in the population of children undergoing transplantation included mortality, acute episodes of rejection, lower levels of Cyclosporine A, and lower values for the International Normalised Ratio of prothrombin.

CONCLUSIONS

For children with congenital and acquired heart disease, the challenges of adherence to treatment can often be overwhelming. Recommendations designed to maximize the impact and scientific rigour of future studies include obtaining quantitative and qualitative measures of adherence, identifying primary and secondary endpoints, emphasizing factors of interest, planning studies with sufficient power to impact on the adherence to treatment, and developing epidemiologic foundations.

Meta-analysis of medical regimen adherence outcomes in pediatric solid organ transplantation

BACKGROUND

Adherence to the medical regimen after pediatric organ transplantation is important for maximizing good clinical outcomes. However, the literature provides inconsistent evidence regarding prevalence and risk factors for nonadherence posttransplant.

METHODS

A total of 61 studies (30 kidney, 18 liver, 8 heart, 2 lung/heart-lung, and 3 with mixed recipient samples) were included in a meta-analysis. Average rates of nonadherence to six areas of the regimen, and correlations of potential risk factors with nonadherence, were calculated.

RESULTS

Across all types of transplantation, nonadherence to clinic appointments and tests was most prevalent, at 12.9 cases per 100 patients per year (PPY). The immunosuppression nonadherence rate was six cases per 100 PPY. Nonadherence to substance use restrictions, diet, exercise, and other healthcare requirements ranged from 0.6 to 8 cases per 100 PPY. Only the rate of nonadherence to clinic appointments and tests varied by transplant type: heart recipients had the lowest rate (4.6 cases per 100 PPY vs. 12.7-18.8 cases per 100 PPY in other recipients). Older age of the child, family functioning (greater parental distress and lower family cohesion), and the child's psychological status (poorer behavioral functioning and greater distress) were among the psychosocial characteristics significantly correlated with poorer adherence. These correlations were small to modest in size (r=0.12-0.18).

CONCLUSIONS

These nonadherence rates provide benchmarks for clinicians to use to estimate patient risk. The identified psychosocial correlates of nonadherence are potential targets for intervention. Future studies should focus on improving the prediction of nonadherence risk and on testing interventions to reduce risk.

Multidimensional Adherence Classification System: initial development with adolescent transplant recipients

As transplantation has progressively become a more viable option for children with life-threatening illness, ensuring that adolescents do not lose their new organ secondary to medication non-adherence is paramount. The first step to addressing non-adherence is adequate assessment of this construct. In this investigation, we introduce the MACS. The MACS includes self-report and drug assay levels. Self-report is a subjective measure with a low false-positive rate, but is vulnerable to social desirability. Drug assays are an objective measure of drug ingestion, but values suggestive of non-adherence may be influenced by medical complications and timing. The MACS builds on the strengths of both methods and attempts to contain their weaknesses. The sample in this study consisted of 82 adolescent solid organ transplant recipients. The non-adherence rate using the MACS in this sample was 61%. Initial data to support this system are promising. The occurrence of rejection episodes and mortality were significantly related to membership in the Genuinely Non-adherent category. Beyond providing initial support for the MACS, we discuss the clinical implications of this adherence classification system.

A national conference to determine research priorities in pediatric solid organ transplantation

The need for evidence-based practice guidelines requires high quality, carefully controlled clinical research trials. This multidisciplinary conference attempted to: identify urgent clinical and research issues, identify obstacles to performing clinical trials, develop concepts for organ-specific and all-organ research and generate a report that would serve as a blueprint for future research initiatives. A few themes became evident. First, young children present a unique immunologic environment which may lead to tolerance, therefore, including young children in immunosuppression withdrawal and tolerance trials may increase the potential benefits of these studies. Second, adolescence poses significant barriers to successful transplantation. Non-adherence may be insufficient to explain poorer outcomes. More studies focused on identification and prevention of non-adherence, and the potential effects of puberty are required. Third, the relatively naive immune system of the child presents a unique opportunity to study primary infections and alloimmune responses. Finally, relatively small numbers of transplants performed in pediatric centers mandate multicenter collaboration. Investment in registries, tissue and DNA repositories will enhance productivity. The past decade has proven that outcomes after pediatric transplantation can be comparable to adults. The pediatric community now has the opportunity to design and complete studies that enhance outcomes for all transplant recipients.

Current issues in pediatric medication adherence

With the recent emphasis on investigating the efficacy of medication in children, it is also important to assess what determines whether pediatric patients do or do not take their medication. In general, children are no better at adhering to drug therapy than older individuals. Dealing with medication nonadherence is essential given its association with a failure to achieve the desired treatment goal. In addition to the many factors that influence adherence in adults, there are some unique challenges faced in the pediatric age group including the role of family (and its dysfunction), the changes of adolescence, and the lack of appropriate drug formulations. Intervention strategies to improve adherence include behavioral and educational strategies. Although there is no consensus as to what is the best approach to promote adherence with therapy, attention should be given to determining what barriers exist and trying to overcome them by involving children and their parents in the treatment planning process. If possible, the medication regimen, taking into account the frequency and timing of administration, should be tailored to the child and family's lifestyle and daily routine. Consideration should be given to the palatability and formulations of medications prescribed for young children. The use of simplified regimens of better tasting medications and age-appropriate delivery mechanisms may enhance the ability of pediatric patients to adhere to their drug therapy.

Identification of medication non-adherence factors in adolescent transplant patients: the patient's viewpoint

Studies report a clear association between medication non-adherence and an unfavorable transplant outcome. The adolescent population, in particular, has difficulty adhering to post-transplant medication regimens. The purpose of this study is to identify, categorize and understand the opinions of adolescent transplant patients regarding why they may not take their medications as prescribed. From January to August 2005, nine adolescent kidney transplant patients at an urban medical center were surveyed and asked to rank-order 33 statements regarding their opinions on why adolescents may not take their medications as prescribed. Q-methodology, a powerful tool in subjective study, was used to identify and categorize the viewpoints of adolescents on this subject. Three factors emerged and were labeled to reflect their distinct viewpoints: (1) Medication Issues (e.g. taste, size, frequency, schedule), (2) Troubled Adolescent (e.g. poor home life, depression, overwhelming situation), and (3) Deliberate Non-Adherer (e.g. attention-seeker, infallible attitude). By understanding these different viewpoints and the factors that contribute to them, it may be easier to identify which management approach to non-adherence works best in specific subgroups of patients.

Cardiovascular risk reduction in high-risk pediatric patients: a scientific statement from the American Heart Association Expert Panel on Population and Prevention Science; the Councils on Cardiovascular Disease in the Young, Epidemiology and Prevention, Nutrition, Physical Activity and Metabolism, High Blood Pressure Research, Cardiovascular Nursing, and the Kidney in Heart Disease; and the Interdisciplinary Working Group on Quality of Care and Outcomes Research

Although for most children the process of atherosclerosis is subclinical, dramatically accelerated atherosclerosis occurs in some pediatric disease states, with clinical coronary events occurring in childhood and very early adult life. As with most scientific statements about children and the future risk for cardiovascular disease, there are no randomized trials documenting the effects of risk reduction on hard clinical outcomes. A growing body of literature, however, identifies the importance of premature cardiovascular disease in the course of certain pediatric diagnoses and addresses the response to risk factor reduction. For this scientific statement, a panel of experts reviewed what is known about very premature cardiovascular disease in 8 high-risk pediatric diagnoses and, from the science base, developed practical recommendations for management of cardiovascular risk.

Over two decades of pediatric heart transplantation: How has survival changed?

OBJECTIVE

In 1984, the first successful infant heart transplant was performed at Texas Children's Hospital. This study analyzes the 21-year experience with pediatric heart transplantation at Texas Children's Hospital to assess whether and how survival has changed over time.

METHODS

Between November 1, 1984, and October 3, 2005, 164 consecutive orthotopic heart transplants were performed on 154 patients. Characteristics: mean age 7.1 +/- 6.0 years, mean body surface area 0.8 +/- 0.5 m(2). Diagnosis at transplant: cardiomyopathy 53.0% (n = 87), congenital heart defect 39.0% (n = 64), retransplant 7.9% (n = 13). Multivariate risk factor analysis of 32 variables was completed by Cox proportional hazards regression models.

RESULTS

Mean follow-up was 5.9 +/- 4.8 years. Overall Kaplan-Meier survival was 82% at 1 year, 65% at 5 years, and 54% at 10 years. After 1995, Kaplan-Meier survival (91% at 1 year and 71% at 5 years) was significantly improved over pre-1995 survival (71% at 1 year, 57% at 5 years, and 48% at 10 years; P =.026). Hospital survival improved in the post-1995 era (96%) compared with the pre-1995 era (77%; P < .001). Life-table analysis by yearly increments demonstrates only an improved survival (pre-1995, 71% -->post-1995, 91%) in the first posttransplant year (P = .001); every subsequent year the mortality rates are the same (P = .92). Risk factors for overall mortality are prolonged postoperative intubation (>5 days) and longer cardiopulmonary bypass time.

CONCLUSIONS

Primarily attributable to an increase in early survival, overall pediatric heart transplant survival is improved. However, after the first posttransplant year, the rate of mortality has not changed in 21 years. This highlights the need for new therapies to treat children both with or in need of a heart transplant.

Indications for Heart Transplantation in Pediatric Heart Disease

Background— Since the initial utilization of heart transplantation as therapy for end-stage pediatric heart disease, improvements have occurred in outcomes with heart transplantation and surgical therapies for congenital heart disease along with the application of medical therapies to pediatric heart failure that have improved outcomes in adults. These events justify a reevaluation of the indications for heart transplantation in congenital heart disease and other causes of pediatric heart failure.

Methods and Results— A working group was commissioned to review accumulated experience with pediatric heart transplantation and its use in patients with unrepaired and/or previously repaired or palliated congenital heart disease (children and adults), in patients with pediatric cardiomyopathies, and in pediatric patients with prior heart transplantation. Evidence-based guidelines for the indications for heart transplantation or retransplantation for these conditions were developed.

Conclusions— This evaluation has led to the development and refinement of indications for heart transplantation for patients with congenital heart disease and pediatric cardiomyopathies in addition to indications for pediatric heart retransplantation.

Cardiovascular Risk Reduction in High-Risk Pediatric Patients

Although for most children the process of atherosclerosis is subclinical, dramatically accelerated atherosclerosis occurs in some pediatric disease states, with clinical coronary events occurring in childhood and very early adult life. As with most scientific statements about children and the future risk for cardiovascular disease, there are no randomized trials documenting the effects of risk reduction on hard clinical outcomes. A growing body of literature, however, identifies the importance of premature cardiovascular disease in the course of certain pediatric diagnoses and addresses the response to risk factor reduction. For this scientific statement, a panel of experts reviewed what is known about very premature cardiovascular disease in 8 high-risk pediatric diagnoses and, from the science base, developed practical recommendations for management of cardiovascular risk.

Heart and lung transplantation in children

During the past two decades, several advances have resulted in marked improvement in medium-term survival for infants and children undergoing heart transplantation. Unfortunately, progress has been less dramatic in the field of lung and heart-lung transplantation, where there is little evidence of improved outcomes. The procedures remain palliative and all transplant recipients are at risk for the adverse effects of non-specific immunosuppression, including infections, lymphoproliferative disorders, and non-lymphoid malignancies. In addition, current immunosuppressive agents have narrow therapeutic windows and exhibit a wide array of organ toxicities, posing special challenges for the young patient who must endure life-long immunosuppression. New immunosuppressive regimens have lowered the rates of acute rejection but appear to have had relatively little impact on the incidence of chronic rejection, the principal cause of late graft loss. The ultimate goal is to induce a state of donor-specific tolerance, wherein the recipient will accept the allograft indefinitely without the need for long-term immunosuppression. This quest is currently being realised in animal models of solid organ transplantation, and offers great hope for children undergoing heart and lung transplantation in the future.

Cardiac allograft vasculopathy in pediatric heart transplant recipients

Metabolic parameters for coronary allograft vasculopathy (CAV) have not been well defined in children. CAV (by angiography or autopsy) was studied in 337 heart recipients on a cyclosporine-based steroid-sparing regimen. Freedom from CAV for all was 79% at 10 years. Fifty-nine patients (18%) developed CAV at a mean of 6.5 +/- 3 years post-transplant. First year rejections were significantly higher in CAV, mean 2.3 vs. 1.4, P = 0.003, odds ratio (OR) 1.8. Rejection with hemodynamic compromise beyond 1 year post-transplant was associated with CAV, P < 0.001, OR 8.4. There was no significant correlation among human leukocyte antigen DR (HLA DR) mismatch, pacemaker use or homocysteine levels and the development of CAV. Maximum cholesterol and low density lipoprotein (LDL) levels were not significantly different. Neither diabetes nor hypertension was significant predictors of CAV on multivariate logistic regression analysis. In conclusion, frequent and severe rejection episodes may predict pediatric CAV. Neither glucose intolerance nor lipid abnormalities appeared to alter risk for CAV in this population.