The Effect of Udenafil on Heart Rate and Blood Pressure in Adolescents With the Fontan Circulation.

The Fontan Udenafil Exercise Longitudinal (FUEL) trial showed that treatment with udenafil was associated with improved exercise performance at the ventilatory anaerobic threshold in children with Fontan physiology. However, it is not known how the initiation of phosphodiesterase 5 inhibitor therapy affects heart rate and blood pressure in this population. These data may help inform patient selection and monitoring after the initiation of udenafil therapy. The purpose of this study is to evaluate the effects of udenafil on vital signs in the cohort of patients enrolled in the FUEL trial. This international, multicenter, randomized, double-blind, placebo-controlled trial of udenafil included adolescents with single ventricle congenital heart disease who had undergone Fontan palliation. Changes in vital signs (heart rate [HR], systolic [SBP] and diastolic blood pressure [DBP]) were compared both to subject baseline and between the treatment and the placebo groups. Additional exploratory analyses were performed to evaluate changes in vital signs for prespecified subpopulations believed to be most sensitive to udenafil initiation. Baseline characteristics were similar between the treatment and placebo cohorts (n = 200 for each). The groups demonstrated a decrease in HR, SBP, and DBP 2 hours after drug/placebo administration, except SBP in the placebo group. There was an increase in SBP from baseline to after 6-min walk test in the treatment and placebo groups, and the treatment group showed an increase in HR (87.4 ± 15.0 to 93.1 ± 19.4 beats/min, p <0.01) after exercise. When comparing changes from baseline to the 26-week study visit, small decreases in both SBP (-1.9 ± 12.3 mm Hg, p = 0.03) and DBP (-3.0 ± 9.6 mm Hg, p <0.01) were seen in the treatment group. There were no clinically significant differences between treatment and placebo group in change in HR or blood pressure in the youngest age quartile, lightest weight quartile, or those on afterload-reducing agents. In conclusion, initiation of treatment with udenafil in patients with Fontan circulation was not associated with clinically significant changes in vital signs, implying that for patients similar to those enrolled in the FUEL trial, udenafil can be started without the requirement for additional monitoring after initial administration.

Cardiac Biomarkers Aid in Differentiation of Kawasaki Disease from Multisystem Inflammatory Syndrome in Children Associated with COVID-19.

Kawasaki disease (KD) and Multisystem Inflammatory Syndrome in Children (MIS-C) associated with COVID-19 show clinical overlap and both lack definitive diagnostic testing, making differentiation challenging. We sought to determine how cardiac biomarkers might differentiate KD from MIS-C. The International Kawasaki Disease Registry enrolled contemporaneous KD and MIS-C pediatric patients from 42 sites from January 2020 through June 2022. The study population included 118 KD patients who met American Heart Association KD criteria and compared them to 946 MIS-C patients who met 2020 Centers for Disease Control and Prevention case definition. All included patients had at least one measurement of amino-terminal prohormone brain natriuretic peptide (NTproBNP) or cardiac troponin I (TnI), and echocardiography. Regression analyses were used to determine associations between cardiac biomarker levels, diagnosis, and cardiac involvement. Higher NTproBNP (≥ 1500 ng/L) and TnI (≥ 20 ng/L) at presentation were associated with MIS-C versus KD with specificity of 77 and 89%, respectively. Higher biomarker levels were associated with shock and intensive care unit admission; higher NTproBNP was associated with longer hospital length of stay. Lower left ventricular ejection fraction, more pronounced for MIS-C, was also associated with higher biomarker levels. Coronary artery involvement was not associated with either biomarker. Higher NTproBNP and TnI levels are suggestive of MIS-C versus KD and may be clinically useful in their differentiation. Consideration might be given to their inclusion in the routine evaluation of both conditions.

The Fontan Udenafil Exercise Longitudinal Trial: Subgroup Analysis.

The Pediatric Heart Network's Fontan Udenafil Exercise Longitudinal (FUEL) Trial (Mezzion Pharma Co. Ltd., NCT02741115) demonstrated improvements in some measures of exercise capacity and in the myocardial performance index following 6 months of treatment with udenafil (87.5 mg twice daily). In this post hoc analysis, we evaluate whether subgroups within the population experienced a differential effect on exercise performance in response to treatment. The effect of udenafil on exercise was evaluated within subgroups defined by baseline characteristics, including peak oxygen consumption (VO2), serum brain-type natriuretic peptide level, weight, race, gender, and ventricular morphology. Differences among subgroups were evaluated using ANCOVA modeling with fixed factors for treatment arm and subgroup and the interaction between treatment arm and subgroup. Within-subgroup analyses demonstrated trends toward quantitative improvements in peak VO2, work rate at the ventilatory anaerobic threshold (VAT), VO2 at VAT, and ventilatory efficiency (VE/VCO2) for those randomized to udenafil compared to placebo in nearly all subgroups. There was no identified differential response to udenafil based on baseline peak VO2, baseline BNP level, weight, race and ethnicity, gender, or ventricular morphology, although participants in the lowest tertile of baseline peak VO2 trended toward larger improvements. The absence of a differential response across subgroups in response to treatment with udenafil suggests that the treatment benefit may not be restricted to specific sub-populations. Further work is warranted to confirm the potential benefit of udenafil and to evaluate the long-term tolerability and safety of treatment and to determine the impact of udenafil on the development of other morbidities related to the Fontan circulation.Trial Registration NCT0274115.

Results of the FUEL Trial.

BACKGROUND: The Fontan operation creates a total cavopulmonary connection, a circulation in which the importance of pulmonary vascular resistance is magnified. Over time, this circulation leads to deterioration of cardiovascular efficiency associated with a decline in exercise performance. Rigorous clinical trials aimed at improving physiology and guiding pharmacotherapy are lacking. METHODS: The FUEL trial (Fontan Udenafil Exercise Longitudinal) was a phase III clinical trial conducted at 30 centers. Participants were randomly assigned udenafil, 87.5 mg twice daily, or placebo in a 1:1 ratio. The primary outcome was the between-group difference in change in oxygen consumption at peak exercise. Secondary outcomes included between-group differences in changes in submaximal exercise at the ventilatory anaerobic threshold, the myocardial performance index, the natural log of the reactive hyperemia index, and serum brain-type natriuretic peptide. RESULTS: Between 2017 and 2019, 30 clinical sites in North America and the Republic of Korea randomly assigned 400 participants with Fontan physiology. The mean age at randomization was 15.5±2 years; 60% of participants were male, and 81% were white. All 400 participants were included in the primary analysis with imputation of the 26-week end point for 21 participants with missing data (11 randomly assigned to udenafil and 10 to placebo). Among randomly assigned participants, peak oxygen consumption increased by 44±245 mL/min (2.8%) in the udenafil group and declined by 3.7±228 mL/min (-0.2%) in the placebo group (P=0.071). Analysis at ventilatory anaerobic threshold demonstrated improvements in the udenafil group versus the placebo group in oxygen consumption (+33±185 [3.2%] versus -9±193 [-0.9%] mL/min, P=0.012), ventilatory equivalents of carbon dioxide (-0.8 versus -0.06, P=0.014), and work rate (+3.8 versus +0.34 W, P=0.021). There was no difference in change of myocardial performance index, the natural log of the reactive hyperemia index, or serum brain-type natriuretic peptide level. CONCLUSIONS: In the FUEL trial, treatment with udenafil (87.5 mg twice daily) was not associated with an improvement in oxygen consumption at peak exercise but was associated with improvements in multiple measures of exercise performance at the ventilatory anaerobic threshold. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02741115.

Balloon angioplasty with stenting to correct a functionally interrupted aorta: A case report with three-year follow-up.

A 16-year-old male presenting with upper extremity hypertension was found to have a severe form of discrete coarctation with complete luminal obliteration, causing a functional interruption of the thoracic aorta. Fluoroscopically guided perforation of the obstruction and creation of a neo-aortic lumen was performed. This was followed by balloon angioplasty and stent placement, successfully relieving the coarctation. The procedural method, acute and late follow-up results, and a discussion of the potential risks and benefits are presented.

Pericardial effusion and tamponade in infants with central catheters.

OBJECTIVE: To describe the clinical presentation, cause, and outcome of central venous catheter (CVC)-related pericardial effusions (PCE) in infants. METHODS: A retrospective case review was conducted of CVC-related PCE at university and private neonatal intensive care units. Data from our cases were combined with published case reports and included clinical presentation and outcome; biochemical evaluation of pericardial fluid; days until diagnosis; cardiothoracic ratios; and CVC characteristics, insertion site, and tip placement site. RESULTS: In our cases, 6 different neonatology groups cared for 14 patients at 6 different hospitals in 2 cities. These data were combined with 47 cases reviewed from the literature. Pericardial fluid was obtained in 54 cases from the combined group and was described qualitatively as consistent with the infusate in 53 of 54 cases (98%). Biochemical analysis was performed in 37 cases, and in 36 of 37 cases (97%), the pericardial fluid was consistent with the infusate. The median gestational age at birth was 30.0 weeks (range: 23.5-42). The median time from CVC insertion to diagnosis was 3.0 days (range: 0.2-37; n = 59). Sudden cardiac collapse was reported in 37 cases (61%), and unexplained cardiorespiratory instability was reported in 22 cases (36%). The CVC tip was last reported within the pericardial reflections on chest radiograph in 56 cases (92%) at the time of PCE diagnosis. The mean cardiothoracic ratio increased 17% (n = 14). No patients died among our cases. Among the reviewed cases, 45% mortality was reported. For the combined group, mortality was 34%. For the combined group, mortality was 8% (3 of 37) in the patients who underwent pericardiocentesis versus 75% (18 of 24) for the patients who did not. In 21 patients, the catheter was withdrawn and remained in use. Survivors and nonsurvivors had comparable gestational age at birth, birth weight, days to PCE diagnosis, and day of life of PCE symptoms/diagnosis. Access site, catheter type, and catheter size were not associated with mortality. An association between larger catheters and shorter time to PCE may be present. Access site and catheter type were not associated with time to PCE. Autopsy specimens reported 6 cases of myocardial necrosis/thrombus formation, 9 cases of perforation without myocardial necrosis/thrombus formation, and 2 cases in which both were reported. CONCLUSIONS: The pericardial fluid found in CVC-associated PCE is consistent with the infusate. We speculate that there are several mechanisms, ranging from frank perforation that seals spontaneously to CVC tip adhesion to the myocardium with diffusion into the pericardial space. Routine radiography should be performed, and the CVC tip should be readily identifiable. The CVC tip should remain outside the cardiac silhouette but still within the vena cavae (approximately 1 cm outside the cardiac silhouette in premature infants and 2 cm in term infants). A change in cardiothoracic ratio may be diagnostic of a PCE, and pericardiocentesis is associated with significantly reduced mortality. Increased awareness of this complication may decrease the mortality associated with CVC-related PCE.