Pediatric Donor Hearts Research Articles

Pediatric donor heart allocation in the United States, 2006-2017: Current patterns and potential for improvement.

To understand current donor heart allocation practices for pediatric transplantation. Despite high waitlist mortality rates among pediatric patients awaiting transplant, a substantial proportion of donor hearts go unused. Analysis of UNOS match run data may identify opportunities to optimize organ utilization. Using UNOS/OPTN data, we evaluated all match runs for pediatric (<18years) donor hearts from 1/1/2006 to 3/31/2017. We assessed final disposition of donor hearts, reasons for donor refusal, and other match run characteristics. Variation in total offers made per organ, and refusal rates by OPOs were also evaluated. Of 7585 pediatric potential donor hearts, 2226 (29.3%) were refused. Hearts accepted underwent a median of 2 offers (IQR: 1-5), compared to 11 (IQR: 5-24) for refused donor hearts. Organ refusal rates decreased from 36.9% in 2006-2009 to 22.3% in 2014-2017 (P<.001). Reasons for refusal included quality (80.9%), size mismatch (57.5%), and known/suspected crossmatch positivity (39.1%). Among 1800 hearts deemed "poor quality" by ≥1 transplant program, less than half (46.6%) were coded "poor quality" by multiple refusing programs. Organ refusal rates ranged from 13.5% to 83.3% across OPOs, and there was no correlation between refusal rates and median number of offers made by the OPO. Although more organs are being used over time, 1 in 5 available pediatric donor hearts are still discarded. The lack of donor evaluation consensus and wide variability in donor refusal rates indicates a need for standardization of donor assessment and match run processes across OPOs.

Pediatric Heart Transplantation in France Since the Implementation of the New Allocation System

Donor-recipient age matching has been introduced into the new French allocation system launched on January 2018. The allocation score is currently weighted by the age difference between the donor and the candidate. The score decreases for candidates 15 to 40 years older than the donor from 100% to 0%. The aim of this study was to evaluate the effect of the new system on pediatric heart transplantation. The study included all new pediatric candidates added to the French waiting list between January 2014 and March 2019 (n=179). The profile and waitlist outcomes of the candidates registered before (2014-2017, n=128) and after (January 2018- March 2019, n=51) the introduction of the new system were compared. The main outcomes were 3-month cumulative incidence (CI) of transplantation, and of waitlist mortality or delisting for worsening medical condition. The CI were estimated using the competing risk analyses and were compared using the Gray's test. The medical characteristics of the patients were similar between the 2 periods except for mechanical ventilation which tended to be more frequent in the first cohort (33% vs 18%, p=0.05). The number of new registrations per year increased by 28% in the second period. Donor heart donations decreased in 2018-2019 period but pediatric donor hearts were more often allocated to pediatric candidates (63% vs 48%). The 3-month CI of transplantation was similar between the 2 periods (53% vs 54%, p=0.41). The 3-month waitlist mortality or delisting for worsening medical condition tended to be lower in 2018-2019 (8% vs 17%, p=0.09). While access to transplantation remains unchanged, a non-significant decrease in 3-month waitlist mortality has been observed since the implementation of the new system.

Review of the discard and/or refusal rate of offered donor hearts to pediatric waitlisted candidates.

We aimed to review current literature on the discard rate of donor hearts offered to pediatric recipients and assess geographical differences. Consequences and ways to reduce the discard rate are discussed. A systemic review on published literature on pediatric transplantation published in English since 2010 was undertaken. Additionally, a survey was sent to international OPOs with the goal of incorporating responses from around the world providing a more global picture. Based on the literature review and survey, there is a remarkably wide range of discard and/or refusal for pediatric hearts offered for transplant, ranging between 18% and 57% with great geographic variation. The data suggest that that the overall refusal rate may have decreased over the last decade. Reasons for organ discard were difficult to identify from the available data. Although the refusal rate of pediatric donor hearts seems to be lower compared to that reported in adults, it is still as high as 57% with geographic variation.

Effects of donor cause of death, ischemia time, inotrope exposure, troponin values, cardiopulmonary resuscitation, electrocardiographic and echocardiographic data on recipient outcomes: A review of the literature.

Heart transplantation has become standard of care for pediatric patients with either end-stage heart failure or inoperable congenital heart defects. Despite increasing surgical complexity and overall volume, however, annual transplant rates remain largely unchanged. Data demonstrating pediatric donor heart refusal rates of 50% suggest optimizing donor utilization is critical. This review evaluated the impact of donor characteristics surrounding the time of death on pediatric heart transplant recipient outcomes. An extensive literature review was performed to identify articles focused on donor characteristics surrounding the time of death and their impact on pediatric heart transplant recipient outcomes. Potential pediatric heart transplant recipient institutions commonly receive data from seven different donor death-related categories with which to determine organ acceptance: cause of death, need for CPR, serum troponin, inotrope exposure, projected donor ischemia time, electrocardiographic, and echocardiographic results. Although DITs up to 8hours have been reported with comparable recipient outcomes, most data support minimizing this period to <4hours. CVA as a cause of death may be associated with decreased recipient survival but is rare in the pediatric population. Otherwise, however, in the setting of an acceptable donor heart with a normal echocardiogram, none of the other data categories surrounding donor death negatively impact pediatric heart transplant recipient survival. Echocardiographic evaluation is the most important donor clinical information following declaration of brain death provided to potential recipient institutions. Considering its relative importance, every effort should be made to allow direct image visualization.

Behavioral economics-A framework for donor organ decision-making in pediatric heart transplantation.

The high discard rate of pediatric donor hearts presents a major challenge for children awaiting heart transplantation. Recent literature identifies several factors that contribute to the disparities in pediatric donor heart usage, including regulatory oversight, the absence of guidelines on pediatric donor heart acceptance, and variation among transplant programs. However, a likely additional contributor to this issue are the behavioral factors influencing transplant team decisions in donor offer scenarios, a topic that has not yet been studied in detail. Behavioral economics and decision psychology provide an excellent foundation for investigating decision-making in the pediatric transplant setting, offering key insights into the behavior of transplant professionals. We conducted a systematic review of published literature in pediatric heart transplant related to behavioral economics and the psychology of decision-making. In this review, we draw on paradigms from these two domains in order to examine how existing aspects of the transplant environment, including regulatory oversight, programmatic variation, and allocation systems, may precipitate potential biases surrounding donor offer decisions. Recognizing how human decision behavior influences donor acceptance is a first step toward improving utilization of potentially viable pediatric donor hearts.

How do we make the best decision to accept a pediatric donor heart?

How do we make the best decision to accept a pediatric donor heart?

Toward a New Strategy for Pediatric Heart Allocation: High Risk Organs for Less Ill Patients?

Purpose Using current allocation schemes, high-risk pediatric donor hearts are under-utilized. This study examined how recipient illness severity may influence acceptance of risk-stratified donor organs and the impact of this paradigm on graft survival/mortality. Methods The UNOS database was queried for pediatric ( 60 and bilirubin Results Severely ill patients were more likely to receive medium or high risk organs (67.2%) than moderately (56.2%) or mildly ill (51.6%) patients (both p Conclusion Illness severity of pediatric heart recipients influences the impact that donor organ risk has on graft failure/mortality. While very ill patients had worse outcomes after transplant with higher risk organs, post-transplant outcomes were comparable among less ill patients, regardless of donor risk. This suggests that higher risk organs may be preferentially allocated to less ill patients, without compromising outcomes, thereby reducing donor waste and overall waitlist mortality.

Pediatric marginal donor hearts: Trends in US national use, 2005-2014.

Pediatric patients awaiting heart transplant face high mortality rates due to donor organ shortages, including non-use of marginal donor hearts. We examined national trends in pediatric marginal donor heart use over time. UNOS data were queried for heart donors <18years from 2005 to 2014. The proportion of donor hearts considered marginal was determined using previously cited marginal characteristics: left ventricular ejection fraction (LVEF) <50%, use of ≥2 inotropes, cerebrovascular death, CDC high-risk status, and eGFR<30mL/min/1.73m2 . Disposition of donor hearts was determined and stratified by marginal donor status. Of 6778 pediatric hearts offered from 2005 to 2014, 2373 (35.0%) were considered marginal. Non-use of marginal donor hearts was significantly higher than that of donor hearts without any marginal characteristics (59.5% vs 20.3%, P<.001). In particular, LVEF<50% and donor inotropes were associated with high rates of organ non-use among pediatric donors. Yet, non-use of marginal donor organs decreased from 67% to 48% from 2005 to 2014 (P<.001). Although the proportion of pediatric donor hearts used for pediatric patients has increased, more than half of donor hearts are declined for use in pediatric recipients due, in part, to perceived marginal status.

Survival Outcomes of Oversized Cardiac Allografts in Pediatric Patients—A Single-Center Experience in Taiwan

ObjectivesAn oversized cardiac allograft may have a negative impact on survival outcomes according to previous studies; however, due to the shortage of pediatric donor hearts, the use of oversized cardiac allografts is sometimes inevitable. In this study, we reported the survival outcomes of pediatric patients in relation with the donor-recipient weight ratio. MethodsTwenty-eight children, aged 3 months to 17 years, with dilated cardiomyopathy underwent primary cardiac transplantation at the National Taiwan University Hospital between 1995 and 2012. We analyzed these patients according to the donor-recipient weight ratio: group 1 (n = 19) with donor-recipient weight ratio <2.5 (median 1.1, interquartile range 1.0–1.6), and group 2 (n = 9) with donor-recipient weight ratio ≥2.5 (median 3.0, inter-quartile range 2.87–3.5). ResultsThe 30-day survival rate was 100% for both group 1 and group 2 (P = 1). The survival rates for group 1 and group 2 were 95% vs 100% at 1 year, 84% vs 89% at 5 years, and 73% vs 61% at 10 years. The median survival was 14.4 years vs 12.9 years (P = .6313). ConclusionIn this cohort, the use of oversized cardiac allograft in pediatric patients for dilated cardiomyopathy did not have a negative effect on short-term and long-term survival.

(179) - Pediatric Marginal Donor Hearts: National Use and Center-Specific Variability

(179) - Pediatric Marginal Donor Hearts: National Use and Center-Specific Variability

(702) - Incidence and Risk Factors for Failed Recovery of Pediatric Donor Hearts

(702) - Incidence and Risk Factors for Failed Recovery of Pediatric Donor Hearts

(138) - Are Pediatric Donor Hearts Viable in Adult Recipients?

(138) - Are Pediatric Donor Hearts Viable in Adult Recipients?

(139) - The Overall Concept of Bridging to Transplantation by an Ventricular Assist Device in Comparison to Bridging by Conservative Treatment - Results Using the United Network for Organ Sharing Database

s S59 those patients with size (defined as > 30% height/weight difference) or gender mismatch to a control group without mismatch. Results: Pediatric donor hearts in all groups had similar 3-year survival, freedom from CAV and NF-MACE to those adult recipients receiving adult donor hearts (See table). 1-year freedom from acute cellular and antibodymediated rejection were also similar. Gender mismatch did not appear to be significant risk factor (data not shown). Size mismatch did not adversely affect outcome among the study groups (see table). Conclusion: The use of pediatric donor hearts, even pre-puberty donor hearts, in appropriately selected adults appear to be viable with acceptable outcomes.

Pediatric Cardiac Transplantation Using Hearts Previously Refused for Quality: A Single Center Experience

Pediatric donor hearts are regularly refused for donor quality with limited evidence as to which donor parameters are predictive of poor outcomes. We compare outcomes of recipients receiving hearts previously refused by other institutions for quality with the outcomes of recipients of primarily offered hearts. Data for recipients aged ≤18 and their donors were obtained. Specific UNOS refusal codes were used to place recipients into refusal and nonrefusal groups; demographics, morbidity and mortality were compared. Kaplan–Meier analysis with log-rank test was used to determine differences in graft survival. A multivariable Cox proportional hazards model was constructed to determine independent risk factors for postoperative mortality. From July 1, 2000 to April 30, 2011, 182 recipients were transplanted and included for analysis. One hundred thirty received a primarily offered heart; 52 received a refused heart. No difference in postoperative complications or graft survival between the two groups (p = 0.190) was found. Prior refusal was not an independent risk factor for recipient mortality. Analysis of this large pediatric cohort examining outcomes with quality-refused hearts shows that in-hospital morbidity and long-term mortality for recipients of quality-refused hearts are no different than recipients of primarily offered hearts, suggesting that donor hearts previously refused for quality are not necessarily unsuitable for transplant and often show excellent outcomes.

First Pediatric Heart Transplantation From a Pediatric Donor Heart in Japan

Since the revision of the Japanese Organ Transplantation Act, children younger than 15 years old can donate their organs after brain death. A teenage boy with endstage restrictive cardiomyopathy underwent the first heart transplantation with a pediatric donor heart in Japan on April 12, 2011. He had a good postoperative clinical course and no histological rejection episodes. His waiting period was relatively short (237 days) compared with adult patients, because of the pediatric patient-first policy for a pediatric donor heart. To increase pediatric heart transplantation in Japan, further enlightenment of the general population about pediatric organ donation is desirable.

Pediatric Heart Transplantation Bridged With Ventricular Assist Devices

Heart transplantation (HTx) is indicated in children with end-stage heart failure or complex inoperable congenital defects. Because of the shortage of pediatric donor hearts, various bridge techniques have been used in pediatric patients to prolong patient survival until a suitable heart becomes available. We reviewed medical records of several pediatric patients in whom bridging with ventricular assist devices was used. All of the patients survived HTx, and are alive and well with no neurologic sequelae. They are NYHA functional class I. Thus, morbidity and mortality were acceptable in this high-risk group of pediatric patients with a ventricular assist device bridging to HTx.

Pediatric Transplantation Using Hearts Refused on the Basis of Donor Quality

There is always more demand than supply of organs in pediatric heart transplantation. Yet, potential donor organs are regularly declined for a variety of reasons, among them donor organ quality as determined by United Network for Organ Sharing (UNOS) refusal code 830 or its equivalent. For the study group institutional and UNOS databases (July 2000 to December 2008) were reviewed to examine outcomes of pediatric heart transplantation using donor hearts that had been previously refused one or more times because of organ quality. Variation between outcomes of this cohort and recipients who received primarily offered heart grafts in a single institution was analyzed. In 29 recipients, transplantation or retransplantation was with heart grafts previously declined on the basis of quality. Recovery distances (p < 0.002) and graft cold ischemic times (p < 0.001) were significantly longer for declined hearts. Operative survival was 93% +/- 5.0% (27 of 29). Seven-year actuarial survival was 74% +/- 10.5%. At the present time, 24 of the 29 recipients (83%) are alive. These results do not vary statistically from those experienced by 84 recipients of 86 primarily offered donor organs during the same time. Despite longer distance recovery (ie, longer graft cold ischemic times), outcomes of pediatric heart transplantation using donor heart grafts refused on the basis of organ quality are highly competitive. Pediatric donor hearts should seldom be declined on the basis of organ quality (UNOS code 830).

Outcome for Pediatric Cardiac Transplantation With and Without Bridge Methods

Heart transplantation is indicated for children with end-stage heart failure or complex inoperable congenital defects. Due to the shortage of pediatric donor hearts, various bridge techniques have been used for pediatric recipients to prolong patient survival until a heart is available. This study evaluates long-term outcome of bridge and nonbridge support for pediatric heart transplantation. Between March 1995 and June 2004, 18 pediatric patients underwent heart transplantation. Six patients (33.3%) underwent biological or mechanical bridge techniques before transplantation. Eight patients (44.4%) required perioperatively extracorporeal membrane oxygenation (ECMO) support. Patient data and records were retrospectively reviewed. Causes of death and long-term outcome were analyzed. Five of eight patients in the ECMO group (62.5%) were successfully decannulated and discharged home with excellent functional classes. No differences in rejection rate, survival rate, and functional class existed between the bridged and nonbridged groups. Overall 1-year and 5-year survival rates were both 83.3% and all have a good functional class. Pediatric heart transplantation can be accomplished with excellent early survival despite multiple prior cardiac operations and relatively severe illness. For the variety in small, low-body-weight pediatric patients, mechanical circulatory support using ECMO is suitable for managing sudden collapse while waiting for heart transplantation, and graft dysfunction after cardiac transplantation. The mortality rate is acceptable in this very high-risk group of patients and long-term outcome is good.

Anti-CD11b monoclonal antibody improves myocardial function after six hours of hypothermic storage

The shortage of pediatric heart donors often necessitates considerable travel time and, as a result, prolonged donor heart ischemia. This excessive hypothermic storage may contribute markedly to myocardial dysfunction in the recipient. We investigated the role of leukocyte-endothelial interactions in this dysfunction in an isolated, immature (mean age, 11.8 +/- 1.6 days) swine heart model using a monoclonal antibody against a leukocyte adhesion molecule. We studied a total of 20 hearts subjected to 6 hours of cardioplegic arrest at 4 degrees C. Group M1/70 (n = 6) received at reperfusion 15 micrograms/mL of a monoclonal antibody F(ab')2 fragment to CD11b, the alpha-subunit of the leukocyte adhesion molecule Mac-1. Group MB10.6 (n = 8) received 15 micrograms/mL of the swine unreactive F(ab')2 MB10.6, and the third group received saline vehicle. Administration of M1/70 resulted in improved postischemic recovery of ventricular function compared with the two control groups (p < 0.05). These data implicate leukocyte-endothelial interactions mediated by the leukocyte adhesion molecule CD11b in myocardial dysfunction after long-term hypothermic ischemia. Specific antiadhesion strategies such as this may safely extend storage time for pediatric donor hearts.

Equitable distribution in pediatric heart transplantation. Arguments in favor of a national list.

The disparity between the supply and demand for pediatric donor hearts remains the major constraint in pediatric heart transplantation. This disparity draws attention to the importance of an equitable distribution policy for pediatric hearts. An examination of the policy on pediatric heart distribution shows that although a governmental task force recommended that these organs be allocated according to a national list, the current policy, developed by the United Network of Organ Sharing, emphasizes the local distribution of pediatric hearts. The decision to allocate organs locally was based on both theoretical and practical concerns about national distribution. In analyzing these concerns, we conclude not only that a national list may be a more equitable means of distribution but also that the arguments against a national list no longer justify a policy favoring local distribution. We suggest, therefore, that the time has come to reconsider implementation of a national list for pediatric heart distribution.