Johnson, Jonathan N.

ABSTRACT Background In recent years, transcatheter implantation devices to restrict pulmonary arterial flow have emerged as a potential alternative to surgical pulmonary artery banding. Case Presentation A term male was diagnosed with critical aortic stenosis (AS) and severely reduced left ventricle (LV) systolic function. He underwent aortic balloon valvuloplasty on day 2 of life, resulting in some antegrade flow, but LV ejection fraction only improved to 15%. He remained ductal dependent for systemic perfusion. Pulmonary over‐circulation ensued with systemic steal evident in his second week of life. On day 14, he underwent a transcatheter stage 1 procedure including the placement of bilateral pulmonary flow restrictor (PFR) devices and ductal stenting. Post‐procedure, he improved clinically, weaned off respiratory support, and transitioned to oral feeds while awaiting cardiac transplant. Twelve days later, he received a donor heart, with an uneventful recovery. He is now 3 years post‐transplant and has excellent graft function, and his transplant course has been unremarkable. Conclusion Transcatheter‐based palliation for a neonate with critical AS, utilizing endoluminal PFRs, proved effective in stabilizing the infant and successfully bridging him to transplant. This highlights an opportunity for the utilization of PFRs in neonatal conditions where control of pulmonary blood flow is imperative as a bridge to transplantation.

ABSTRACTBackgroundPediatric organ transplantation is the primary treatment for end‐organ failure. Improving medication adherence and healthcare compliance can decrease healthcare burdens, graft rejection, morbidity, and mortality. Adolescents commonly struggle with non‐adherence, necessitating a smooth transition to adult care. This systematic review aims to assess and evaluate the effectiveness of existing transition tools and models used in the care of pediatric solid organ transplant recipients (pSOTR).MethodsA systematic literature review of studies in electronic databases (PubMed, Google Scholar, and Mendeley) on interventions improving transition in pediatric solid organ transplant recipients (pSOTR) from 2000 to 2022 was conducted. Included studies involved pSOTR before the age of 12 years transitioning to adult care.ResultsA lower proportion of graft acute rejection was observed among pSOTR with more than two transition interventions (10.088%, 95% CI: 0.901%–27.441%, I2 = 85.95%, p < 0.0001, random effects, five studies, n = 155) compared to those with two or fewer interventions (13.892%, 95% CI: 4.588%–27.142%, I2 = 74.73%, p = 0.0014, random effects, six studies, n = 140). Additionally, a significant association was found between transition protocols and lower rejection rates (χ2 = 10.57, p = 0.0011), with multiple protocols showing better outcomes (χ2 = 5.091, p = 0.024). Although adherence scores differed significantly with and without transition protocols (χ2 = 8.75, p = 0.0126), no significant difference was found between single and multiple protocol groups (χ2 = 4.8, p = 0.091).ConclusionThis review identifies various transition models and their impact on adherence and graft rejection, which correlate with morbidity and mortality and influence transplant outcomes. The heterogeneity of data within the current literature necessitates further research to establish causality and develop a standardized transition program aimed at improving patient outcomes.

Background: The Fontan procedure has transformed the management of congenital heart defects (CHD) characterized by single ventricle physiology, yet it predisposes individuals to Fontan-associated liver disease (FALD), potentially leading to end-stage liver disease (ESLD). Combined heart and liver transplantation (CHLT) emerges as a therapeutic option, but evidence on its efficacy, safety, and outcomes remains limited. Objectives: This systematic review and single-arm meta-analysis aims to comprehensively evaluate the literature on CHLT in Fontan patients, focusing on patient characteristics, perioperative outcomes, and post-transplant morbidity and mortality. Methods: A systematic search of PubMed, Embase, and Cochrane Central Register of Controlled Trials was conducted following PRISMA guidelines. Studies meeting the intervention of CHLT in Fontan patients were included and data were collected and synthesized using proportion meta-analysis techniques. Statistical analysis was carried out using R software. Results: Four studies met inclusion criteria, comprising 67 Fontan patients undergoing CHLT. All included studies were observational retrospective cohorts performed in the United States. One-year survival rate post-CHLT was 84% (95% CI 66%-94%), Figure 1A. Rates of liver and heart graft rejection were low 10% (95% CI 3%-33%) and 8% (95% CI 2%-31%), respectively, Figure 1B. Postoperative complications included acute kidney injury 72% (95% CI 46%-88%), temporary dialysis 31% (95% CI 14%-55%), neurologic events 14% (95% CI 5%-34%), infection 24% (95% CI 6%-63%), and unplanned medical procedures 41% (95% CI 24%-60%), Figure 1C. Conclusion: CHLT in Fontan patients demonstrates promising survival rates, but graft rejection and postoperative complications pose challenges. The rate of renal complications is particularly notable and requires further evaluation. Future research should prioritize comparative different management strategies and long-term follow-up to refine protocols and optimize outcomes.

Background Early detection of left and right ventricular systolic dysfunction (LVSD and RVSD respectively) in children can lead to intervention to reduce morbidity and death. Existing artificial intelligence algorithms can identify LVSD and RVSD in adults using a 12‐lead ECG; however, its efficacy in children is uncertain. We aimed to develop novel artificial intelligence–enabled ECG algorithms for LVSD and RVSD detection in pediatric patients. Methods and Results We identified 10 142 unique pediatric patients (age≤18) with a 10‐second, 12‐lead surface ECG within 14 days of a transthoracic echocardiogram, performed between 2002 and 2022. LVSD was defined quantitatively by left ventricular ejection fraction (LVEF). RVSD was defined semiquantitatively. Novel pediatric models for LVEF ≤35% and LVEF <50% achieved excellent test areas under the curve of 0.93 (95% CI, 0.89–0.98) and 0.88 (95% CI, 0.83–0.94) respectively. The model to detect LVEF <50% had a sensitivity of 0.85, specificity of 0.80, positive predictive value of 0.095, and negative predictive value of 0.995. In comparison, the previously validated adult data‐derived model for LVEF <35% achieved an area under the curve of 0.87 (95% CI, 0.84–0.90) for LVEF ≤35% in children. A novel pediatric model for any RVSD detection reached a test area under the curve of 0.90 (0.87–0.94). Conclusions An artificial intelligence–enabled ECG demonstrates accurate detection of both LVSD and RVSD in pediatric patients. While adult‐trained models offer good performance, improvements are seen when training pediatric‐specific models.

Background Quadricuspid aortic valve (QAV) is an exceedingly rare congenital heart defect (CHD) which has not been well-defined in a pediatric population. Methods The Mayo Clinic echocardiography database was retrospectively analyzed to identify patients ≤18 years diagnosed with QAV from January 1990 to December 2023. Patients with truncus arteriosus were excluded. All images were independently reviewed to define morphology of the QAV by using the Hurwitz and Roberts classification. Results Fourteen patients with QAV were identified with a median age at time of diagnosis being 10.5 years (interquartile range [IQR] 6-14 years). Male-to-female ratio was 3:1. Associated CHDs were present in 50% (n = 7) patients. The most common morphological subtypes of QAV were Type D in 43% (n = 6) and Type B in 29% (n = 4). Aortic regurgitation was the most frequently associated valvular abnormality affecting 86% (n = 12) cases, with greater than moderate regurgitation in only two patients. Aortic valve stenosis was observed in 14% (n = 2) patients. Ascending aortic dilatation was present in 21% (3/14) of the cohort, but only 14% (1/7) of isolated QAV patients. At a mean follow up of 11 ± 6.6 years and a median follow-up age of 22 years (IQR 14-27 years), survival was 100% with no primary interventions on the aortic valve or aorta. However, four patients required surgical interventions for associated CHDs. Conclusion Among children with QAV, almost half of the patients had additional CHD. Aortic regurgitation was the predominant hemodynamic abnormality. Long-term survival was excellent with minimal progression during childhood and adolescence.

While significant progress has been made in reducing disparities within the US health care system, notable gaps remain. This article explores existing disparities within pediatric congenital heart disease care. Congenital heart disease, the most common birth defect and a leading cause of infant death, has garnered substantial attention, revealing certain disparities within the US health care system. Factors such as race, ethnicity, insurance coverage, socioeconomic status, and geographic location are all commonalities that significantly affect health disparities in pediatric congenital heart disease. This comprehensive review sheds light on disparities from diverse perspectives in pediatric care, demonstrates the inequities and inequalities leading to these disparities, presents effective solutions, and issues a call to action for providers, institutions, and the health care system. Recognizing and addressing these disparities is imperative for ensuring equitable care and enhancing the long‐term well‐being of children affected by congenital heart disease. Implementing robust, evidence‐based frameworks that promote responsible and safe interventions is fundamental to enduring change.

Ebstein anomaly is a myopathy of the right ventricle characterized by failure of tricuspid valve delamination with accompanying tricuspid regurgitation. Its rarity, considerable anatomic variability, and frequent absence of symptoms can make the timing of surgery challenging. Contemporary tricuspid repair techniques can be performed with low mortality and bidirectional cavopulmonary anastomosis reduces the risk of operation when right ventricular function is poor. Here, we present a patient who presented late for surgery, failed high-risk conventional surgery and required heart transplantation.

KCNQ1 encodes the voltage-gated α-subunit of the I Ks channel complex (Kv7.1), and KCNQ1 mutations are associated with multiple arrhythmia syndromes. Over the past 12 years, hundreds of different KCNQ1 mutations have been linked to congenital long QT syndrome but only three KCNQ1 variants, each identified in only one family, are linked to familial early-onset AF (<50 years of age). The scant genetic linkage between KCNQ1 and early-onset AF raises the question as to whether these KCNQ1 variants actually cause familial early-onset AF or simply unmask a latent genetic predisposition. We now report that a single KCNQ1 variant, pArg231His or R231H, is identified in five unrelated families with a high penetrance of familial early-onset AF. Whole-cell patch clamp of cells heterologously expressing the obligatory I Ks β-subunit KCNE1 with wild-type KCNQ1 (WT) or WT and R231H (to mimic the patients’ genotypes) showed that cells co-expressing R231H increased current at negative and resting membrane potentials. Additionally, currents recorded from cells using a human atrial action potential (AP) waveform at physiological temperature showed that WT is minimally activated during the atrial AP and co-expression of R231H increases current measured during the atrial AP waveform by greater than 20-fold (WT, n = 10; WT & R231H, n = 12, p<0.0001). Simulations using a computational model of a human atrial AP also predicted that I Ks is normally minimally activated in the atria and R231H would dramatically increase I Ks and shorten the atrial AP. We conclude that KCNQ1 mutations are capable of causing familial early-onset AF by increasing I Ks during the atrial AP and shortening atrial refractoriness.

Evidence from medicine and other fields has shown that gender diversity results in better decision making and outcomes. The incoming workforce of congenital heart specialists (especially in pediatric cardiology) appears to be more gender balanced, but past studies have shown many inequities. Gender‐associated differences in leadership positions, opportunities presented for academic advancement, and recognition for academic contributions to the field persist. In addition, compensation packages remain disparate if evaluated based on gender with equivalent experience and expertise. This review explores these inequities and has suggested individual and institutional changes that could be made to recruit and retain women, monitor the climate of the institution, and identify and eliminate bias in areas like salary and promotions.