Is there an optimal organ acceptance rate for pediatric heart transplantation: "A sweet spot"?

"Take it or leave it": Analysis of pediatric heart offers for transplantation in Switzerland

BACKGROUND

There is a shortage of donor hearts in Switzerland, especially for pediatric recipients. However, the rate and reason for refusals of pediatric donor hearts offered in Switzerland has not been systematically analyzed.

METHODS

The national transplant database, Swiss Organ Allocation System, was searched for all hearts from Swiss and foreign donors younger than 16 years from 2015 to 2020. The numbers of accepted and refused hearts and early outcome were assessed, and the reasons for refusal were retrospectively analyzed.

RESULTS

A total of 136 organs were offered to the three Swiss pediatric heart centers and foreign donor procurement organizations. Of these, 26/136 (19%) organs were accepted and transplanted: 18 hearts were transplanted in Switzerland, and 13 of these were foreign. Reasons for refusal were (1) no compatible recipient due to blood group or weight mismatch, 89.4%; (2) medical, meaning organ too marginal for transplantation, 7.4%; (3) logistic, 1.4%; and (4) other, 1.8%. Five organs were refused in Switzerland by one center but later accepted and successfully transplanted by another center. Hearts from outside Switzerland were transplanted significantly less than Swiss hearts (n = 16/120 vs. 10/16, p < .001).

CONCLUSION

The most common reason for refusing a pediatric donor heart is lack of compatibility with the recipient. Few hearts are refused for medical reasons. A more generous acceptance seems to be justified in selected patients. Switzerland receives a high number of foreign offers, but their rate of acceptance is lower than that of Swiss donations.

Pediatric heart transplant waiting times in the United States since the 2016 allocation policy change

We describe waiting times for pediatric heart transplant (HT) candidates after the 2016 revision to the US allocation policy. The OPTN database was queried for pediatric HT candidates listed between 7/2016 and 4/2019. Of the 1789 included candidates, 65% underwent HT, 14% died/deteriorated, 8% were removed for improvement, and 13% were still waiting at the end of follow-up. Most candidates were status 1A at HT (81%). Median wait times differ substantially by listing status, blood type, and recipient weight. The likelihood of HT was lower in candidates <25 kg and in those with blood type O; The <25 kg, blood type O subgroup experiences longer wait times and higher wait list mortality. For status 1A candidates, median wait times were 108 days (≤25 kg, blood type O), 80 days (≤25 kg, non-O), 47 days (>25 kg, O), and 24 days (>25 kg, non-O). We found that centers with more selective organ acceptance practices, based on a lower median Pediatric Heart Donor Assessment Tool (PH-DAT) score for completed transplants, experience longer status 1A wait times for their listed patients. These data can be used to counsel families and to select appropriate advanced heart failure therapies to support patients to transplant.

Decline of increased risk donor offers increases waitlist mortality in paediatric heart transplantation

BACKGROUND

Increased risk donors in paediatric heart transplantation have characteristics that may increase the risk of infectious disease transmission despite negative serologic testing. However, the risk of disease transmission is low, and refusing an IRD offer may increase waitlist mortality. We sought to determine the risks of declining an initial IRD organ offer.

METHODS AND RESULTS

We performed a retrospective analysis of candidates waitlisted for isolated PHT using 20072017 United Network of Organ Sharing datasets. Match runs identified candidates receiving IRD offers. Competing risks analysis was used to determine mortality risk for those that declined an initial IRD offer with stratified Cox regression to estimate the survival benefit associated with accepting initial IRD offers. Overall, 238/1067 (22.3%) initial IRD offers were accepted. Candidates accepting an IRD offer were younger (7.2 versus 9.8 years, p < 0.001), more often female (50 versus 41%, p = 0.021), more often listed status 1A (75.6 versus 61.9%, p < 0.001), and less likely to require mechanical bridge to PHT (16% versus 23%, p = 0.036). At 1- and 5-year follow-up, cumulative mortality was significantly lower for candidates who accepted compared to those that declined (6% versus 13% 1-year mortality and 15% versus 25% 5-year mortality, p = 0.0033). Decline of an IRD offer was associated with an adjusted hazard ratio for mortality of 1.87 (95% CI 1.24, 2.81, p < 0.003).

CONCLUSIONS

IRD organ acceptance is associated with a substantial survival benefit. Increasing acceptance of IRD organs may provide a targetable opportunity to decrease waitlist mortality in PHT.

Heart transplantation in 47 children: single-center experience from China

Background

To perform a retrospective analysis of 47 cases of pediatric heart transplantation in a single Chinese center.

Methods

The study included 47 cases of heart transplantation under 18 years old, completed between Sep 1^st, 2008 and Dec 31^st, 2018. We carried out statistical analysis of the clinical features of the donors and recipients, perioperative information, postoperative complications and short- and mid-term survival.

Results

The study included 24 males and 23 females. The average age on transplantation was 10.34±4.80 years (minimum 3 months, median 11.00 years). Preoperative diagnosis included 36 cases of cardiomyopathy, 9 cases of complex congenital heart disease (CHD), and 2 cases of cardiac tumor. Four patients received cardiac surgery before. The donors’ average age was 20.89±11.84 years, including 19 donors under 18 years old and 28 donors over 18 years old. The mean donor/recipient body weight ratio was 1.58±0.58. The mean duration of intraoperative cardiopulmonary bypass (CPB) was 119.00±53.47 minutes, in which the mean CPB-assist time was 79.71±48.21 minutes. The average duration of postoperative mechanical ventilation was 32.00 (18.50–54.00) hours, and the average intensive care unit (ICU) stay was 7.00 (4.94–11.28) days. Postoperative complications occurred in 20 cases (42.55%). The 1-year, 3-year, and 5-year survival rate after operation was 95.74%, 93.01%, and 93.01% respectively.

Conclusions

Heart transplantation is an effective means for end-stage heart disease in children. The clinical outcome of pediatric heart transplantation in our center is satisfactory, with low incidence of postoperative complications and high short- and mid-term survival rates.

Pediatric cardiac waitlist mortality-Still too high

Cardiac transplantation for children with end-stage cardiac disease with no other medical or surgical options is now standard. The number of children in need of cardiac transplant continues to exceed the number of donors considered "acceptable." Therefore, there is an urgent need to understand which recipients are in greatest need of transplant before becoming "too ill" and which "marginal" donors are acceptable in order to reduce waitlist mortality. This article reviewed primarily pediatric studies reported over the last 15 years on waitlist mortality around the world for the various subgroups of children awaiting heart transplant and discusses strategies to try to reduce the cardiac waitlist mortality.

ISHLT consensus statement on donor organ acceptability and management in pediatric heart transplantation

The number of potential pediatric heart transplant recipients continues to exceed the number of donors, and consequently the waitlist mortality remains significant. Despite this, around 40% of all donated organs are not used and are discarded. This document (62 authors from 53 institutions in 17 countries) evaluates factors responsible for discarding donor hearts and makes recommendations regarding donor heart acceptance. The aim of this statement is to ensure that no usable donor heart is discarded, waitlist mortality is reduced, and post-transplant survival is not adversely impacted.

Paediatric heart transplantation: an update

Heart transplantation is a standard treatment for selected paediatric patients with end-stage heart disease. With improvement in surgical techniques, organ procurement and preservation strategies, immunosuppressive drugs, and more sophisticated monitoring strategies, survival following transplantation has increased over time. However, rejection, infection, renal failure, post-transplant lymphoproliferative disease and post-transplant cardiac allograft vasculopathy still preclude long-term survival. Therefore, continued multidisciplinary scientific efforts are needed for future gains. This review focuses on the current status, outcomes and ongoing challenges including patient selection, indications and contraindications, national and international survivals, post-transplant complications and quality of life.

Donor considerations in pediatric heart transplantation

Donors for pediatric heart transplantation are accepted based on variety of donor factors. There is wide variability in practice across centers and lack of evidence to guide standardized approach for some donor characteristics. This article reviews current practice and evidence for donor evaluation in pediatric heart transplantation.

Variability in donor selection among pediatric heart transplant providers: Results from an international survey

There is considerable variability in donor acceptance practices among adult heart transplant providers; however, pediatric data are lacking. The aim of this study was to assess donor acceptance practices among pediatric heart transplant professionals. The authors generated a survey to investigate clinicians' donor acceptance practices. This survey was distributed to all members of the ISHLT Pediatric Council in April 2018. A total of 130 providers responded from 17 different countries. There was a wide range of acceptable criteria for potential donors. These included optimal donor-to-recipient weight ratio (lower limit: 50%-150%, upper limit: 120%-350%), maximum donor age (25-75 years), and minimum acceptable left ventricular EF (30%-60%). Non-US centers demonstrated less restrictive donor selection criteria and were willing to accept older donors (50 vs 35 years, P < 0.001), greater size discrepancy (upper limit weight ratio 250% vs 200%, P = 0.009), and donors with a lower EF (45% vs 50%, P < 0.001). Recipient factors were most influential in the decision to accept marginal donors including recipients requiring ECMO support, ventilator support, and highly sensitized patients with a negative XM. However, programmatic factors impacted the decision to decline marginal donors including recent programmatic mortalities and concerns for programmatic restrictions from regulatory bodies. There is significant variation in donor acceptance practices among pediatric heart transplant professionals. Standardization of donor acceptance practices through the development of a consensus statement may help to improve donor utilization and reduce waitlist mortality.