Andrew S. Mackie

Background: There are limited data on prescription patterns in adolescents and adults with Fontan circulation. Methods: We conducted a retrospective analysis of patients 13 years of age and older enrolled between 2022 and 2024 in the Fontan Outcomes Network (now SV‐ONE [Single Ventricle Outcomes Network]) who had undergone Fontan operation without subsequent Fontan takedown or heart transplantation. Demographics, clinical variables, and medications prescribed were assessed. Logistic regression was used to identify factors associated with prescribed cardiac medications. Results: There were 639 patients (age range 13–67 years, 55.6% male, 81.1% White race, 46.8% dominant left ventricle) enrolled at 16 centers. The most frequently prescribed medication classes were antiplatelets (75.6%) and renin‐angiotensin system inhibitors (55.9%). Direct oral anticoagulant prescription (15.0%) exceeded that of warfarin (11.6%). SGLT2 (sodium glucose cotransporter 2) inhibitors were prescribed to 6.3% of patients, and angiotensin receptor/neprilysin inhibitors were prescribed to 2.2%. Moderate or severely decreased systolic ventricular function was most strongly associated with prescription of digoxin (odds ratio [OR], 4.2 [95% CI, 2.1–8.3]). Protein losing enteropathy was most strongly associated with prescription of diuretics (OR, 22.9 [95% CI, 8.1–64.9]), mineralocorticoid receptor agonists (OR, 5.3 [95% CI, 2.4–11.8]), and pulmonary vasodilators (OR, 5.2 [95% CI, 2.5–10.8]). Conclusions: In a multicenter cohort of adolescents and adults with Fontan circulation, medications indicated for biventricular heart failure with reduced ejection fraction are often used despite an absence of supportive evidence in this distinct circulation. Future prospective analysis may provide further insight into shifting prescribing patterns and response to therapy.

Background: In the FUEL (Fontan Udenafil Exercise Longitudinal) trial, a positive treatment effect was identified for outcomes at the ventilatory anaerobic threshold but not for the primary outcome, oxygen consumption (V o ₂ ) at peak exercise. This disparate response may be explained by the physiologic challenge of improving peak V o ₂ in participants with near‐normal baseline exercise performance. Methods: Participants were divided into subgroups by baseline predicted peak V o ₂ (2 2 2 improved significantly after 6 months of udenafil treatment, when compared with placebo (0.23±4.17 mL/kg per min versus −0.90±3.74 mL/kg per min; P =0.021). Secondary outcome measures, including V o ₂ at ventilatory anaerobic threshold ( P =0.023), work at ventilatory anaerobic threshold ( P =0.032), and the myocardial performance index ( P =0.007) were all significantly improved as well. A significant interaction was found between exercise subgroups and response to udenafil for peak V o ₂ ( P =0.036) but not for other outcomes. Conclusions: In this post hoc subgroup analysis, after exclusion of patients with Fontan circulation with near‐normal baseline peak V o ₂ , a positive treatment effect of udenafil was identified for the primary outcome of peak V o ₂ . The interaction between baseline peak V o ₂ and treatment may have influenced the outcome of the FUEL trial. Registration: URL: https://clinicaltrials.gov ; Unique identifier: NCT0274115.

BACKGROUND: Cardiovascular dimensions measured during pediatric echocardiograms must be normalized for body size. However, other variables may confound their interpretation, such as age and abnormal body habitus. This retrospective cross-sectional study of the Canadian Congenital and Pediatric Cardiology Research Network aimed to create Z score equations for commonly measured dimensions in pediatric 2-dimensional echocardiography that were free of residual confounding effects of body size, body mass index, and age. METHODS: The reference sample consisted of >20 000 children without heart disease from 9 institutions who underwent clinical echocardiography that was reported as normal. A generalized additive model for location, scale, and shape (GAMLSS) was used to model the expected distributions of measurements as a function of sex, height, weight, body mass index, and age. RESULTS: Compared with a model that only considered body surface area, the proposed Z scores demonstrated less bias in subgroups of overweight, young, and early school-aged children. CONCLUSIONS: The proposed Z score equations may improve diagnostic and therapeutic accuracy by ensuring that body size, body mass index, and age do not confound the interpretation of measurements.

This study examined the experiences of Indigenous youth and young adults with pediatric onset chronic health conditions who had or were about to transition from pediatric to adult healthcare services. Transition is the process by which youth develop the knowledge and self-management skills needed to manage their health condition, ideally beginning around age 12–13 and continuing until the mid-20s. There is a growing body of literature on healthcare transition, but there is an absence of literature on Indigenous youth, who face additional barriers to accessing healthcare relative to non-Indigenous Canadians. The primary objective of this study was to identify the supports and barriers for Indigenous youth with childhood-onset chronic health conditions transitioning from pediatric to adult healthcare services. The research was done in the province of Alberta, Canada, in collaboration with a Community Advisory Committee comprised of Indigenous healthcare providers, Elders and Knowledge Keepers and guided by a community-based participatory research approach. Semi-structured qualitative interviews (n = 46) were conducted with Indigenous youth, caregivers, and healthcare providers. There were three Talking Circles, two for youth (9 participants) and one for caregivers (6 participants). Three research assistants coded the transcripts thematically using NVivo. The key findings were presented to the Community Advisory Committee for feedback to validate the interpretation of the qualitative data. The thematic findings include: (1) systemic inequalities exacerbate gaps in healthcare; (2) intergenerational trauma created unique barriers for Indigenous youth; (3) long-term relationships with care providers as a protective factor; (4) the incorporation of Indigenous worldviews into healthcare services to aid transition; and (5) assuming new responsibilities as an adult. The participants provided recommendations to improve healthcare service delivery including the need for Indigenous transition supports in community and improving education for healthcare practitioners about transition and Indigenous worldviews. This study demonstrates the complexity of the transition experience for Indigenous youth with pediatric onset chronic health conditions. The identified barriers to successful transition could be addressed through systems level changes and the development of Indigenous specific transition support services. Such approaches need to be Indigenous-led and incorporate Indigenous culture, language, and teachings.