Pediatric heart transplant

Acute Kidney Injury Requiring Dialysis After Pediatric Heart Transplant

BACKGROUND

Acute kidney injury (AKI) is a common complication of pediatric heart transplant, with a subset of patients developing severe AKI requiring dialysis (AKI-D). We aimed to identify the epidemiology, risk factors, and outcomes of postoperative AKI-D in pediatric heart transplant recipients.

METHODS

We retrospectively identified all pediatric first-time, single-organ heart transplants at our institution from 2014 to 2022. Postoperative AKI was defined as AKI within 2 weeks of transplant. Unadjusted and adjusted logistic regression were used to identify characteristics associated with AKI-D, and unadjusted time-to-event analyses were used to determine the association between AKI-D and survival free of kidney failure.

RESULTS

Among 177 patients included, 116 (66%) developed postoperative AKI of any stage, including 13 (7%) who developed AKI-D with median time from transplant to dialysis initiation of 6 days (IQR 3-13). In adjusted models, increased cardiopulmonary bypass time (OR 1.19, 95% CI 1.04-1.37, per 15 min increase in bypass time) and higher weight at transplant were associated with higher odds of AKI-D, whereas patient demographics and pretransplant kidney function were not associated with AKI-D. AKI-D was associated with greater mortality during initial hospitalization (46% vs. 1%, p < 0.001) and a lower rate of survival free of kidney failure.

CONCLUSIONS

The incidence of AKI-D after pediatric heart transplant was 7%, with extended cardiopulmonary bypass time associated with postoperative AKI-D even in adjusted models. Further research is needed to improve the prediction and management of AKI-D in this population.

[Formula: see text] The multifaceted role of neuropsychology in pediatric solid organ transplant: preliminary guidelines and strategies for clinical practice

The incidence of pediatric solid organ transplantation (SOT) has increased in recent decades due to medical and surgical advances as well as improvements in organ procurement. Survival rates for pediatric kidney, liver, and heart transplantation are above 85% but patients continue to experience complex healthcare needs over their lifetime. Long-term developmental and neuropsychological sequelae are becoming increasingly recognized in this population, although preliminary work is limited and deserves further attention. Neuropsychological weaknesses are often present prior to transplantation and may be related to underlying congenital conditions as well as downstream impact of the indicating organ dysfunction on the central nervous system. Neuropsychological difficulties pose risk for functional complications, including disruption to adaptive skill development, social-emotional functioning, quality of life, and transition to adulthood. The impact of cognitive dysfunction on health management activities (e.g., medication adherence, medical decision-making) is also an important consideration given these patients' lifelong medical needs. The primary aim of this paper is to provide preliminary guidelines and clinical strategies for assessment of neuropsychological outcomes across SOT populations for pediatric neuropsychologists and the multidisciplinary medical team, including detailing unique and shared etiologies and risk factors for impairment across organ types, and functional implications. Recommendations for clinical neuropsychological monitoring as well as multidisciplinary collaboration within pediatric SOT teams are also provided.

ERG mediates the inhibition of NK cell cytotoxicity through the HLX/STAT4/Perforin signaling pathway, thereby promoting the progression of myocardial infarction

This study aimed to investigate the role of ERG in the HLX/STAT4/Perforin signaling axis, impacting natural killer (NK) cell cytotoxicity and myocardial infarction (MI) progression. NK cell cytotoxicity was assessed via co-culture and 51Cr release assays. Datasets GSE34198 and GSE97320 identified common differentially expressed genes in MI. NK cell gene expression was analyzed in MI patients and healthy individuals using qRT-PCR and Western blotting. ERG's regulation of HLX and STAT4's regulation of perforin were studied through computational tools (MEM) and ChIP experiments. HLX's influence on STAT4 was explored with the MG132 proteasome inhibitor. Findings were validated in a mouse MI model.ERG, a commonly upregulated gene, was identified in NK cells from MI patients and mice. ERG upregulated HLX, leading to STAT4 proteasomal degradation and reduced Perforin expression. Consequently, NK cell cytotoxicity decreased, promoting MI progression. ERG mediates the HLX/STAT4/Perforin axis to inhibit NK cell cytotoxicity, fostering MI progression. These results provide vital insights into MI's molecular mechanisms.

Pulmonary hemodynamics before and after pediatric heart transplantation

BACKGROUND

Pulmonary hypertension (PH) may limit the outcome of pediatric heart transplantation (pHTx). We evaluated pulmonary hemodynamics in children undergoing pHTx.

METHODS

Cross-sectional, single-center, observational study analyzing pulmonary hemodynamics in children undergoing pHTx.

RESULTS

Twenty-three children (female 15) underwent pHTx at median (IQR) age of 3.9 (.9-8.2) years with a time interval between first clinical signs and pHTx of 1.1 (.4-3.2) years. Indications for pHTx included cardiomyopathy (CMP) (n = 17, 74%), congenital heart disease (CHD) (n = 5, 22%), and intracardiac tumor (n = 1, 4%). Before pHTx, pulmonary hemodynamics included elevated pulmonary artery pressure (PAP) 26 (18.5-30) mmHg, pulmonary capillary wedge pressure (PCWP) 19 (14-21) mmHg, left ventricular enddiastolic pressure (LVEDP) 17 (13-22) mmHg. Transpulmonary pressure gradient (TPG) was 6.5 (3.5-10) mmHg and pulmonary vascular resistance (Rp) 2.65 WU*m2 (1.87-3.19). After pHTx, at immediate evaluation 2 weeks after pHTx PAP decreased to 20.5 (17-24) mmHg, PCWP 14.5 (10.5-18) mmHg (p < .05), LVEDP 16 (12.5-18) mmHg, TPG 6.5 (4-12) mmHg, Rp 1.49 (1.08-2.74) WU*m2 resp.at last invasive follow up 4.0 (1.4-6) years after pHTx, to PAP 19.5 (17-21) mmHg (p < .05), PCWP 13 (10.5-14.5) mmHg (p < .05), LVEDP 13 (10.5-14) mmHg, TPG 7 (5-9.5) mmHg, Rp 1.58 (1.38-2.19) WU*m2 (p < .05). In CHD patients PAP increased (p < .05) after pHTx at immediate evaluation and decreased until last follow-up (p < .05), while in CMP patients there was a continuous decline of mean PAP values immediately after HTx (p < .05).

CONCLUSIONS

While PH before pHTx is frequent, after pHTx the normalization of PH starts immediately in CMP patients but is delayed in CHD patients.

Heart transplantation for pediatric foreign nationals in the United States

BACKGROUND

This study aimed to clarify survival outcomes, waitlist mortality, and waitlist days of heart transplantation of pediatric foreign nationals compared to pediatric United States (US) citizens.

METHODS

We retrieved data from March 2012 to June 2021 in the United Network Organ Sharing (UNOS) registry.

RESULTS

Of 5857 pediatric patients newly waitlisted, 133 (2.27%) patients were non-US citizen/non-US residents (non-citizen non-resident [NCNR]). Patients with congenital heart disease were higher in the US citizen group than in the NCNR group (51.9% vs. 22.6%, p < .001); 76.7% of patients in the NCNR group (102/133) had cardiomyopathy. Of the 133 NCNRs, 111 patients (83.5%) underwent heart transplantation, which was significantly higher than that in the US citizen group (68.6%, p < .001). The median waitlist time was 71 days (IQR, 22-172 days) in the NCNR group and 74 days (29-184 days) in the US citizen group (p = .48). Survival after heart transplant was significantly better in the NCNR group than in the US citizen group (n = 3982; logrank test p = .015).

CONCLUSIONS

Heart transplantation for pediatric foreign nationals was mostly indicated for cardiomyopathy, and their transplant rate was significantly higher than that in the US citizen group, with better survival outcomes. The better survival outcomes in the NCNR group compared to the US citizen group can likely be attributed to the differing diagnoses for which transplantation was performed.

Partial heart transplantation can ameliorate donor organ utilization

BACKGROUND

The treatment of babies with unrepairable heart valve dysfunction remains an unsolved problem because there are no growing heart valve implants. However, orthotopic heart transplants are known to grow with recipients.

AIM

Partial heart transplantation is a new approach to delivering growing heart valve implants, which involves transplantation of the part of the heart containing the valves only. In this review, we discuss the benefits of this procedure in children with unrepairable valve dysfunction.

CONCLUSION

Partial heart transplantation can be performed using donor hearts with poor ventricular function and slow progression to donation after cardiac death. This should ameliorate donor heart utilization and avoid both primary orthotopic heart transplantation in children with unrepairable heart valve dysfunction and progression of these children to end-stage heart failure.