Elimination of 15N-thymidine after oral administration in human infants.

Background: We have developed a new clinical research approach for the quantification of cellular proliferation in human infants to address unanswered questions about tissue renewal and regeneration. The approach consists of oral 15N-thymidine administration to label cells in S-phase, followed by Multi-isotope Imaging Mass Spectrometry for detection of the incorporated label in cell nuclei. To establish the approach, we performed an observational study to examine uptake and elimination of 15N-thymidine.

Assessing Donor-Recipient Size Mismatch in Pediatric Heart Transplantation: Lessons Learned From Over 7,500 Transplants.

Background: To date, no studies have identified an optimal metric to match donor-recipient (D-R) pairs in pediatric heart transplantation (HT).

Objectives: This study sought to identify size mismatch metrics that predicted graft survival post-HT.

Methods: D-R pairs undergoing HT in Pediatric Heart Transplant Society database from 1993 to 2021 were included.

Abnormal Global Longitudinal Strain During Anthracycline Treatment Predicts Future Cardiotoxicity in Children.

Global longitudinal strain (GLS) is a sensitive predictor of cardiotoxicity in adults with cancer. However, the significance of abnormal GLS during childhood cancer treatment is less well-understood. The objective was to evaluate the use of GLS for predicting later cardiac dysfunction in pediatric cancer survivors exposed to high-dose anthracyclines.

Short-term clinical outcomes and predicted cost savings of dd-cfDNA-led surveillance after pediatric heart transplantation.

Background: Endomyocardial biopsy (EMB)-led surveillance is common after pediatric heart transplantation (HT), with some centers performing periodic surveillance EMBs indefinitely after HT. Donor derived cell-free DNA (dd-cfDNA)-led surveillance offers an alternative, but knowledge about its clinical and economic outcomes, both key drivers of potential utilization, are lacking.

Methods: Using single-center recipient and center-level data, we describe clinical outcomes prior to and since transition from EMB-led surveillance to dd-cfDNA-led surveillance of pediatric and young adult HT recipients.

Cardiac MRI-Derived Inferior Vena Cava Cross-Sectional Area Correlates with Measures of Fontan-Associated Liver Disease.

There is currently no clear consensus on screening techniques to evaluate the presence or severity of Fontan-associated liver disease (FALD). Cardiac MRI (CMR) is used routinely for post-Fontan surveillance, but CMR-derived measures that relate to the severity of FALD are not yet defined. This was a cross-sectional single-center study of post-Fontan patients who underwent a CMR.

Responsiveness to second and third dose of mRNA COVID-19 vaccination in adolescent and young adult heart transplant recipients.

Background: Third-dose mRNA COVID-19 vaccine is currently recommended in the United States for SOT recipients based in part on data showing diminished immune response, including Ab production, after a two-dose regimen. Data on vaccine response in adolescent and young adult SOT recipients are limited, including no data reported on third-dose responsiveness.

Methods: Results of serologic testing in a convenience sample of 28 vaccinated adolescent and young adult HT recipients at a single institution were collected from the medical record and summarized.

Early findings after integration of donor-derived cell-free DNA into clinical care following pediatric heart transplantation.

Background: Endomyocardial biopsy (EMB) is costly and discomforting yet remains a key component of surveillance after pediatric heart transplantation (HT). Donor-derived cell-free DNA (dd-cfDNA) has been histologically validated with high negative predictive value, offering an alternative to surveillance EMB (sEMB).

Methods: We implemented an alternative surveillance protocol using commercially available dd-cfDNA assays in place of sEMB after pediatric HT.

Impact of the 2016 revision of US Pediatric Heart Allocation Policy on waitlist characteristics and outcomes.

US Pediatric Heart Allocation Policy was recently revised, deprioritizing candidates with cardiomyopathy while maintaining status 1A eligibility for congenital heart disease (CHD) candidates on "high-dose" inotropes. We compared waitlist characteristics and mortality around this change. Status 1A listings decreased (70% to 56%, P < .

Improving paediatric cardiologists' awareness about the needs of childhood cancer survivors: results of a single-centre directed educational initiative.

Background: Cardiovascular disease is a leading cause of morbidity and mortality in childhood cancer survivors. Cardiologists must be aware of risk factors and long-term follow-up guidelines, which have historically been the purview of oncologists. Little is known about paediatric cardiologists' knowledge regarding the cardiotoxicity of cancer treatment and how to improve this knowledge.

Neutropenia in pediatric heart transplant recipients.

Neutropenia has been reported in pediatric heart transplant recipients, but its association with infectious morbidity and mortality is unknown. We sought to determine neutropenia's prevalence and impact on infection, rejection, and survival. A retrospective analysis of pediatric heart transplant recipients from March 2005 to August 2015 was performed.

Preoperative Use of CT Angiography in Infants With Coarctation of the Aorta.

Background: Computed tomographic angiography (CTA) and echocardiography (echo) are used preoperatively in coarctation of the aorta to define arch hypoplasia and great vessel branching. We sought to determine differences in quantitative measurements, as well as surgical utility, between modalities.

Methods: Infants (less than six months) with both CTA and echo prior to coarctation repair from 2004 to 2013 were included.

Cardio-oncology Related to Heart Failure: Pediatric Considerations for Cardiac Dysfunction.

Although tremendous advances in pediatric cancer treatment have improved the survival of many children, these patients remain at increased risk of early morbidity and mortality with cardiovascular disease as a leading cause of death. Heightened awareness in providers with increased surveillance and improvement in cardiovascular imaging modalities have led to earlier detection of cardiac dysfunction, but the outcomes remain poor once this has dysfunction developed. A great deal of work remains to be done to refine screening and identify high-risk patients more precisely, and to develop more evidence-based strategies for effective primary and secondary cardioprotection and treatment.

Appropriateness of Outpatient Echocardiograms Ordered by Pediatric Cardiologists or Other Clinicians.

Objective: To assess the appropriateness and diagnostic yield of TTEs ordered by various pediatric providers according to the pediatric appropriate use criteria (AUC) for outpatient transthoracic echocardiography (TTE) before its release.

Study Design: Clinic notes of patients aged ≤18 years who underwent initial outpatient TTE between April and September 2014 were reviewed to determine the AUC indication, and appropriateness was assigned based on the AUC document. Ordering physicians were categorized into cardiologists, primary care physicians (PCPs; including pediatricians and family practitioners [FPs]), and noncardiology subspecialists.

Appropriate Use and Clinical Impact of Echocardiographic "Evaluation of Murmur" in Pediatric Patients.

Objective: To determine the appropriateness and yield of transthoracic echocardiograms (TTE) for murmur evaluation based on the pediatric Appropriate Use Criteria (AUC) and study the influence of patient age and physician experience on TTE appropriateness, yield, and ordering frequency.

Design: Retrospective review of medical records of patients referred to our practice for murmur evaluation from April to September 2014. Data collected included indication for TTE, patient age, physician experience since fellowship, TTE findings and exit diagnosis.