Efficacy of a Transition Program in Adolescents and Young Adults With Congenital Heart Disease: The TRANSITION-CHD Randomized Controlled Trial.

PURPOSE: Currently, nearly 90% of patients with congenital heart disease (CHD) reach adulthood in relatively good health. Structured transition programs have emerged to support adolescents and young adults in transitioning to adult care structures, improve their autonomy, and limit healthcare ruptures. The TRANSITION-CHD randomized controlled trial aimed to assess the impact of a transition program on health-related quality of life (HRQoL) in adolescents and young adults with CHD. METHODS: From January 2017 to February 2020, 200 subjects with a CHD, aged 13-25 years, were enrolled in a prospective, controlled, multicenter study and randomized in two balanced groups (transition program vs. standard of care). The primary outcome was the change in PedsQL self-reported HRQoL score between baseline and 12-month follow-up, using an intention-to-treat analysis. The secondary outcomes were the change in disease knowledge, physical health (cardiopulmonary fitness, physical activity), and mental health (anxiety, depression). RESULTS: The change in HRQoL differed significantly between the transition group and the control group (mean difference = 3.03, 95% confidence interval (CI) = [0.08; 5.98]; p = .044; effect size = 0.30), in favor of the intervention group. A significant increase was also observed in the self-reported psychosocial HRQoL (mean difference = 3.33, 95% CI = [0.01; 6.64]; p = .049; effect size = 0.29), in the proxy-reported physical HRQoL (mean difference = 9.18, 95% CI = [1.86; 16.51]; p = .015; effect size = 0.53), and in disease knowledge (mean difference = 3.13, 95% CI = [1.54; 4.72]; p < .001; effect size = 0.64). DISCUSSION: The TRANSITION-CHD program improved HRQoL and disease knowledge in adolescents and young adults with CHD, supporting the generalization and systematization of similar preventive interventions in pediatric and congenital cardiology.

Aerobic physical capacity and health-related quality of life in children with sickle cell disease.

BACKGROUND: Aerobic fitness is a predictor of cardiovascular health which correlates with health-related quality of life in the general population. The aim is to evaluate the aerobic capacity by cardiopulmonary exercise test (CPET) in children with sickle cell disease in comparison with healthy matched controls. METHODS: Controlled cross-sectional study. RESULTS: A total of 72 children (24 with sickle cell disease and 48 healthy controls), aged 6-17 years old were enrolled. Children with sickle cell disease had a poor aerobic capacity, with median VO2max Z-score values significantly lower than matched controls (-3.55[-4.68; -2.02] vs. 0.25[-0.22; 0.66], P < 0.01, respectively), and a high proportion of 92% children affected by an impaired aerobic capacity (VO2max Z-score < -1.64). The VO2max decrease was associated with the level of anemia, the existence of a homozygote HbS/S mutation, restrictive lung disease and health-related quality of life. CONCLUSION: Aerobic capacity is poor in children with sickle cell disease. VO2max decrease is associated with the level of anemia, the existence of a homozygote HbS/S mutation, lung function, and health-related quality of life. These results represent a signal in favor of early initiation of cardiac rehabilitation in patients with sickle cell disease. CLINICAL TRIALS: NCT05995743. IMPACT: Aerobic fitness is a predictor of cardiovascular health which correlates with health-related quality of life in the general population. Aerobic capacity (VO2max) is poor in children with sickle cell disease, despite the absence of any pattern of heart failure. VO2max decrease was associated with the level of anemia, the existence of a homozygote HbS/S mutation, restrictive lung disease, and health-related quality of life. These results are in favor of early initiation of cardiac rehabilitation in children with sickle cell disease.

Early hybrid cardiac rehabilitation in congenital heart disease: the QUALIREHAB trial.

BACKGROUND AND AIMS: Cardiopulmonary fitness in congenital heart disease (CHD) decreases faster than in the general population resulting in impaired health-related quality of life (HRQoL). As the standard of care seems insufficient to encourage and maintain fitness, an early hybrid cardiac rehabilitation programme could improve HRQoL in CHD. METHODS: The QUALIREHAB multicentre, randomized, controlled trial evaluated and implemented a 12-week centre- and home-based hybrid cardiac rehabilitation programme, including multidisciplinary care and physical activity sessions. Adolescent and young adult CHD patients with impaired cardiopulmonary fitness were randomly assigned to either the intervention (i.e. cardiac rehabilitation) or the standard of care. The primary outcome was the change in HRQoL from baseline to 12-month follow-up in an intention-to-treat analysis. The secondary outcomes were the change in cardiovascular parameters, cardiopulmonary fitness, and mental health. RESULTS: The expected number of 142 patients was enroled in the study (mean age 17.4 ± 3.4 years, 52% female). Patients assigned to the intervention had a significant positive change in HRQoL total score [mean difference 3.8; 95% confidence interval (CI) 0.2; 7.3; P = .038; effect size 0.34], body mass index [mean difference -0.7 kg/m2 (95% CI -1.3; -0.1); P = .022; effect size 0.41], level of physical activity [mean difference 2.5 (95% CI 0.1; 5); P = .044; effect size 0.39], and disease knowledge [mean difference 2.7 (95% CI 0.8; 4.6); P = .007; effect size 0.51]. The per-protocol analysis confirmed these results with a higher magnitude of differences. Acceptability, safety, and short-time effect of the intervention were good to excellent. CONCLUSIONS: This early hybrid cardiac rehabilitation programme improved HRQoL, body mass index, physical activity, and disease knowledge, in youth with CHD, opening up the possibility for the QUALIREHAB programme to be rolled out to the adult population of CHD and non-congenital cardiac disease.

Ryanodine receptor dysfunction causes senescence and fibrosis in Duchenne dilated cardiomyopathy.

BACKGROUND: Duchenne muscular dystrophy (DMD) is an X-linked disorder characterized by progressive muscle weakness due to the absence of functional dystrophin. DMD patients also develop dilated cardiomyopathy (DCM). We have previously shown that DMD (mdx) mice and a canine DMD model (GRMD) exhibit abnormal intracellular calcium (Ca2+) cycling related to early-stage pathological remodelling of the ryanodine receptor intracellular calcium release channel (RyR2) on the sarcoplasmic reticulum (SR) contributing to age-dependent DCM. METHODS: Here, we used hiPSC-CMs from DMD patients selected by Speckle-tracking echocardiography and canine DMD cardiac biopsies to assess key early-stage Duchenne DCM features. RESULTS: Dystrophin deficiency was associated with RyR2 remodelling and SR Ca2+ leak (RyR2 Po of 0.03 ± 0.01 for HC vs. 0.16 ± 0.01 for DMD, P < 0.01), which led to early-stage defects including senescence. We observed higher levels of senescence markers including p15 (2.03 ± 0.75 for HC vs. 13.67 ± 5.49 for DMD, P < 0.05) and p16 (1.86 ± 0.83 for HC vs. 10.71 ± 3.00 for DMD, P < 0.01) in DMD hiPSC-CMs and in the canine DMD model. The fibrosis was increased in DMD hiPSC-CMs. We observed cardiac hypocontractility in DMD hiPSC-CMs. Stabilizing RyR2 pharmacologically by S107 prevented most of these pathological features, including the rescue of the contraction amplitude (1.65 ± 0.06 µm for DMD vs. 2.26 ± 0.08 µm for DMD + S107, P < 0.01). These data were confirmed by proteomic analyses, in particular ECM remodelling and fibrosis. CONCLUSIONS: We identified key cellular damages that are established earlier than cardiac clinical pathology in DMD patients, with major perturbation of the cardiac ECC. Our results demonstrated that cardiac fibrosis and premature senescence are induced by RyR2 mediated SR Ca2+ leak in DMD cardiomyocytes. We revealed that RyR2 is an early biomarker of DMD-associated cardiac damages in DMD patients. The progressive and later DCM onset could be linked with the RyR2-mediated increased fibrosis and premature senescence, eventually causing cell death and further cardiac fibrosis in a vicious cycle leading to further hypocontractility as a major feature of DCM. The present study provides a novel understanding of the pathophysiological mechanisms of the DMD-induced DCM. By targeting RyR2 channels, it provides a potential pharmacological treatment.

Use of T1 mapping in cardiac MRI for the follow-up of Fabry disease in a pediatric population.

Background: Fabry disease (FD) is a rare X-linked lysosomal disorder caused by pathogenic variants in the alpha-galactosidase-A gene (GLA). Life threatening complications in adulthood include chronic kidney failure, strokes and the cardiac involvement which is the leading cause of mortality. Usually, it presents with hypertrophic cardiomyopathy, together with arrhythmia and conduction abnormalities. An early indicator is decreased T1 value on cardiac magnetic resonance (CMR). Enzyme replacement therapy (ERT) is effective on some extra-cardiac symptoms but its effect on cardiac lesions depends on the level of initial myocardial lesions. CMR is routinely used to monitor cardiac involvement in FD due to its capacity for tissular characterization. However, there is a lack of data on the pediatric population to understand how to integrate CMR into early therapeutic decisions. Method: Monocentric longitudinal study carried out at Montpellier University Hospital from 2016 to 2022. All pediatric patients with FD were evaluated over time with clinical, biological, and cardiac imaging (CMR, echocardiography). Results: Out of the six patients included, (3 males), five were treated with ERT during the study. Low T1 values were observed in 4 patients. The normalization of T1 values was observed after 4 years of ERT in 3 patients. Conclusion: Due to the lack of strong clinical and biological markers of FD in pediatric patients, initiation and follow-up of ERT efficacy remain challenging. CMR with T1-mapping, a noninvasive method, could play a role in the evaluation of early cardiac impairment in young patients at diagnosis and during follow-up with or without ERT.

Multimodal imaging for cardiac follow-up and management of giant coronary aneurysm related to Kawasaki disease in childhood: a case report.

Background: Kawasaki disease (KD) is a rare paediatric condition that can lead to giant coronary aneurysms. Follow-up of such complex coronary lesions remains a challenge, and their management is difficult to standardize. Case summary: Our present case concerns a 17-year-old boy who suffered a giant aneurysm of the left coronary artery, complicated by an asymptomatic stenosis. During regular follow-up, his annual cardiopulmonary exercise test revealed signs of ischaemia (ST depression and premature ventricular complexes). After several further stress tests with inconsistent results, he underwent invasive coronary angiography that revealed significant stenosis with a positive fractional flow reserve (FFR). Discussion: We discuss the challenges of diagnosing and managing coronary artery stenosis in paediatric patients with KD, particularly in cases with calcified and thrombosed lesions. A multimodal approach is crucial, including non-invasive imaging, and coronary angiography with optical coherence tomography and FFR. The evaluation of the lesion and its follow-up is an important factor in anticipating the best therapeutic choice for each patient.

Generation of patient-specific induced pluripotent stem cell lines with Type 2 Long QT Syndrome and the KCNH2 c.379C > T pathogenic variant.

Type 2 Long QT Syndrome (LQT2) is a rare genetic heart rhythm disorder causing life-threatening arrhythmias. We derived induced pluripotent stem cell (iPSC) lines from two patients with LQT2, aged 18 and 6, both carrying a heterozygous missense mutation on the 3rd and 11th exons of KCNH2. The iPSC lines exhibited normal genomes, expressed pluripotent markers, and differentiated into trilineage embryonic layers. These patient-specific iPSC lines provide a valuable model to study the molecular and functional impact of the hERG channel gene mutation in LQT2 and to develop personalized therapeutic approaches for this syndrome.

Reference Values of Cardiopulmonary Exercise Test Parameters in the Contemporary Paediatric Population.

BACKGROUND: The evaluation of health status by cardiopulmonary exercise test (CPET) has shown increasing interest in the paediatric population. Our group recently established reference Z-score values for paediatric cycle ergometer VO2max, applicable to normal and extreme weights, from a cohort of 1141 healthy children. There are currently no validated reference values for the other CPET parameters in the paediatric population. This study aimed to establish, from the same cohort, reference Z-score values for the main paediatric cycle ergometer CPET parameters, apart from VO2max. RESULTS: In this cross-sectional study, 909 healthy children aged 5-18 years old underwent a CPET. Linear, quadratic, and polynomial mathematical regression equations were applied to identify the best CPET parameters Z-scores, according to anthropometric parameters (sex, age, height, weight, and BMI). This study provided Z-scores for maximal CPET parameters (heart rate, respiratory exchange ratio, workload, and oxygen pulse), submaximal CPET parameters (ventilatory anaerobic threshold, VE/VCO2 slope, and oxygen uptake efficiency slope), and maximum ventilatory CPET parameters (tidal volume, respiratory rate, breathing reserve, and ventilatory equivalent for CO2 and O2). CONCLUSIONS: This study defined paediatric reference Z-score values for the main cycle ergometer CPET parameters, in addition to the existing reference values for VO2max, applicable to children of normal and extreme weights. Providing Z-scores for CPET parameters in the paediatric population should be useful in the follow-up of children with various chronic diseases. Thus, new paediatric research fields are opening up, such as prognostic studies and clinical trials using cardiopulmonary fitness outcomes. Trial registration NCT04876209-Registered 6 May 2021-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT04876209 .

Isolated Ventricular Inversion: A Rare Complex Congenital Heart Disease With Neonatal Cyanosis.

A 1-day-old girl was referred for a cardiology consultation for a mean saturation at 80% without respiratory distress. Echocardiography showed an isolated ventricular inversion. This entity is extremely rare, with fewer than 20 cases reported. This case report describes the clinical evolution and the complex surgical management of this pathology. (Level of Difficulty: Advanced.).

Reference values of aerobic fitness in the contemporary paediatric population.

AIMS: There has been a growing interest in the use of markers of aerobic physical fitness (VO2max assessed by cardiopulmonary exercise test (CPET)) in the follow-up of paediatric chronic diseases. The dissemination of CPET in paediatrics requires valid paediatric VO2max reference values to define the upper and lower normal limits. This study aimed to establish VO2max reference Z-score values, from a large cohort of children representative of the contemporary paediatric population, including those with extreme weights. METHODS AND RESULTS: In this cross-sectional study, 909 children aged 5 to 18 years old from the general French population (development cohort) and 232 children from the general German and US populations (validation cohort) underwent a CPET, following the guidelines on high-quality CPET assessment. Linear, quadratic, and polynomial mathematical regression equations were applied to identify the best VO2max Z-score model. Predicted and observed VO2max values using the VO2max Z-score model, and the existing linear equations were compared, in both development and validation cohorts. For both sexes, the mathematical model using natural logarithms of VO2max, height, and BMI was the best fit for the data. This Z-score model could be applied to normal and extreme weights and was more reliable than the existing linear equations, in both internal and external validity analyses (https://play.google.com/store/apps/details?id=com.d2l.zscore). CONCLUSION: This study established reference Z-score values for paediatric cycloergometer VO2max using a logarithmic function of VO2max, height, and BMI, applicable to normal and extreme weights. Providing Z-scores to assess aerobic fitness in the paediatric population should be useful in the follow-up of children with chronic diseases. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT04876209.

Risk factors for early occurrence of malnutrition in infants with severe congenital heart disease.

To identify the risk factors of early occurrence of malnutrition in infants with severe congenital heart disease (CHD) during their first year of life. Retrospective longitudinal multicenter study carried out from January 2014 to December 2020 in two tertiary care CHD centers. Four CHD hemodynamic groups were identified. Malnutrition was defined by a Waterlow score under 80% and/or underweight under -2 standard deviations. A total of 216 infants with a severe CHD, e.g., requiring cardiac surgery, cardiac catheterization, or hospitalization for heart failure during their first year of life, were included in the study. Malnutrition was observed among 43% of the cohort, with the highest prevalence in infants with increased pulmonary blood flow (71%) compared to the other hemodynamic groups (p < 0.001). In multivariate analysis, low birthweight (OR 0.62, 95% CI 0.44-0.89, p = 0.009), CHD with increased pulmonary blood flow (OR 4.80, 95% CI 1.42-16.20, p = 0.08), heart failure (OR 9.26, 95% CI 4.04-21.25, p < 0.001), and the number of hospitalizations (OR 1.35, 95% CI 1.08 l-1.69, p = 0.009) during the first year of life were associated with malnutrition (AUC 0.85, 95% CI 0.79-0.90).  Conclusions: In infants with a severe CHD, early occurrence of malnutrition during the first year of life affected a high proportion of subjects. CHD with increased pulmonary blood flow, low birthweight, heart failure, and repeated hospitalizations were risk factors for malnutrition. Further studies are required to identify optimal nutritional support in this population. What is Known: • Malnutrition is a known morbidity and mortality factor in children with severe congenital heart disease. What is New: • Early occurrence of malnutrition during the first year of life in infant severe congenital heart disease (CHD) was high (43%). • CHD with increased pulmonary blood flow, low birthweight, heart failure, and repeated hospitalizations during the first year of life were risk factors for malnutrition.

Generation of catecholaminergic polymorphic ventricular tachycardia patient-specific induced pluripotent stem cell line.

Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) is a genetic disorder characterized by ventricular tachycardia, that can cause the heart to stop beating leading to death. The prevalence is 1/10.000 and in approximately 60% of cases, the syndrome can be due to a mutation of the cardiac ryanodine receptor gene (RyR2). We derived an induced pluripotent stem cell (iPSC) line from an 11-year-old patient blood-cells, carrying a heterozygous missense mutation on the 8th exon of the RyR2 N-terminal part. This reprogramed CPVT line displayed normal karyotype, expressed pluripotent markers and had a capacity to differentiate in trilineage embryonic layers.

Use of speckle tracking echocardiography to detect late anthracycline-induced cardiotoxicity in childhood cancer: A prospective controlled cross-sectional study.

BACKGROUND: This study aimed to detect late sub-clinical patterns of cardiac dysfunction using speckle tracking echocardiography (STE) in children with cancer remission more than 12 months after the end of anthracycline treatment. METHODS: This prospective controlled study enrolled 196 children, 98 of which had been treated with anthracyclines (mean age 10.8 ± 3.6 years; 51% female) and 98 were age- and gender-matched healthy subjects in a 1:1 case-control design. Conventional echocardiographic variables were collected for left ventricle (LV) and right ventricle (RV). STE analyses were performed in the LV longitudinal, radial, and circumferential displacements and in the RV free wall longitudinal displacement. The association between LV global longitudinal strain (GLS) and the main clinical and biological parameters was evaluated. RESULTS: After a mean time interval of 5.1 ± 3.2 years since the end of chemotherapy (mean cumulative anthracycline dose of 192 ± 96 mg/m2), conventional echocardiographic measures were normal. GLS was significantly decreased in the anthracycline group (-19.1% vs. -21.5%, P < 0.0001), with a higher proportion of children with abnormal values (Z-score < -2 in 18.6% vs. 1.0%, P < 0.0001). No association was found between GLS and clinical or biological parameters. Circumferential strain was significantly worse in the anthracycline group (-16.8% vs. -19.4%, P < 0.0001), and radial strain significantly better (+51.4% vs. +35.9%, P < 0.0001). RV conventional echocardiography and STE parameters were normal and not different between anthracycline and control groups. CONCLUSIONS: The existence of a modified LV strain despite normal LV function in children treated with anthracyclines represents an important perspective for cardiomyopathy surveillance in childhood cancer survivors. Clinical Trial Registration -ClinicalTrials.gov Identifier: NCT02893787.

Early Myocardial Dysfunction and Benefits of Cardiac Treatment in Young X-Linked Duchenne Muscular Dystrophy Mice.

CONTEXT: Duchenne muscular dystrophy (DMD) is associated with a progressive alteration in cardiac function. OBJECTIVE: The aim of this study was to detect early cardiac dysfunction using the high sensitive two-dimensional speckle-tracking echocardiography (2D strain) in mdx mouse model and to investigate the potential preventive effects of the S107 ryanodine receptor (RyR2) stabilizer on early onset of DMD-related cardiomyopathy. METHODS AND RESULTS: Conventional echocardiography and global and segmental left ventricle (LV) 2D strains were assessed in male mdx mice and control C57/BL10 mice from 2 to 12 months of age. Up to 12 months of age, mdx mice showed preserved myocardial function as assessed by conventional echocardiography. However, global longitudinal, radial, and circumferential LV 2D strains significantly declined in mdx mice compared to controls from the 9 months of age. Segmental 2D strain analysis found a predominant alteration in posterior, inferior, and lateral LV segments, with a more marked impairment with aging. Then, mdx mice were treated with S107 in the drinking water at a dose of 250 mg/L using two different protocols: earlier therapy from 2 to 6 months of age and later therapy from 6 to 9 months of age. The treatment with S107 was efficient only when administered earlier in very young animals (from 2 to 6 months of age) and prevented the segmental alterations seen in non-treated mdx mice. CONCLUSIONS: This is the first animal study to evaluate the therapeutic effect of a drug targeting early onset of DMD-related cardiomyopathy, using 2D strain echocardiography. Speckle-tracking analyses revealed early alterations of LV posterior segments that could be prevented by 4 months of RyR2 stabilization.

Assessment of left ventricular dyssynchrony by speckle tracking echocardiography in children with duchenne muscular dystrophy.

Prognosis of Duchenne muscular dystrophy (DMD) is related to cardiac dysfunction. Two dimensional-speckle tracking echocardiography (2D-STE) has recently emerged as a non-invasive functional biomarker for early detection of DMD-related cardiomyopathy. This study aimed to determine, in DMD children, the existence of left ventricle (LV) dyssynchrony using 2D-STE analysis. This prospective controlled study enrolled 25 boys with DMD (mean age 11.0 ± 3.5 years) with normal LV ejection fraction and 50 age-matched controls. Three measures were performed to assess LV mechanical dyssynchrony: the opposing-wall delays (longitudinal and radial analyses), the modified Yu index, and the time-to-peak delays of each segment. Feasibility and reproducibility of 2D-STE dyssynchrony were evaluated. All three mechanical dyssynchrony criteria were significantly higher in the DMD group than in healthy subjects: (1) opposing-wall delays in basal inferoseptal to basal anterolateral segments (61.4 ± 45.3 ms vs. 18.3 ± 50.4 ms, P < 0.001, respectively) and in mid inferoseptal to mid anterolateral segments (58.6 ± 35.3 ms vs. 42.4 ± 36.4 ms, P < 0.05, respectively), (2) modified Yu index (33.3 ± 10.1 ms vs. 28.5 ± 8.1 ms, P < 0.05, respectively), and (3) most of time-to-peak values, especially in basal and mid anterolateral segments. Feasibility was excellent and reliability was moderate to excellent, with ICC values ranging from 0.49 to 0.97. Detection of LV mechanical dyssynchrony using 2D-STE analysis is an easily and reproducible method in paediatric DMD. The existence of an early LV mechanical dyssynchrony visualized using 2D-STE analysis in children with DMD before the onset of cardiomyopathy represents a perspective for future paediatric drug trials in the DMD-related cardiomyopathy prevention.Clinical Trial Registration Clinicaltrials.gov NCT02418338. Post-hoc study, registered on April 16, 2015.

Cardiorespiratory fitness, muscle fitness, and physical activity in children with long QT syndrome: A prospective controlled study.

Background: In children with congenital long QT syndrome (LQTS), the risk of arrhythmic events during exercise commonly makes it difficult to balance exercise restrictions versus promotion of physical activity. Nevertheless, in children with LQTS, cardiorespiratory fitness, muscle fitness, and physical activity, have been scarcely explored. Materials and methods: In this prospective, controlled, cross-sectional study, 20 children with LQTS (12.7 ± 3.7 years old) and 20 healthy controls (11.9 ± 2.4 years old) were enrolled. All participants underwent a cardiopulmonary exercise test, a muscular architecture ultrasound assessment, (cross-sectional area on right rectus femoris and pennation angle), a handgrip muscular strength evaluation, and a standing long broad jump test. The level of physical activity was determined using with a waist-worn tri-axial accelerometer (Actigraph GT3X). Results: Peak oxygen uptake (VO2peak) and ventilatory anaerobic threshold (VAT) were lower in children with LQTS than in healthy controls (33.9 ± 6.2 mL/Kg/min vs. 40.1 ± 6.6 mL/Kg/min, P = 0.010; 23.8 ± 5.1 mL/Kg/min vs. 28.8 ± 5.5 mL/Kg/min, P = 0.007, respectively). Children with LQTS had lower standing long broad jump distance (119.5 ± 33.2 cm vs. 147.3 ± 36.1 cm, P = 0.02) and pennation angle (12.2 ± 2.4° vs. 14.3 ± 2.8°, P = 0.02). No differences in terms of moderate-to-vigorous physical activity were observed (36.9 ± 12.9 min/day vs. 41.5 ± 18.7 min/day, P = 0.66), but nearly all children were below the WHO guidelines. Conclusion: Despite similar physical activity level, cardiorespiratory fitness and muscle fitness in children with LQTS were lower than in healthy controls. The origin of this limitation seemed to be multifactorial, involving beta-blocker induced chronotropic limitation, physical and muscle deconditioning. Cardiovascular rehabilitation could be of interest in children with LQTS with significant physical limitation.

Health-related quality of life and physical activity in children with inherited cardiac arrhythmia or inherited cardiomyopathy: the prospective multicentre controlled QUALIMYORYTHM study rationale, design and methods.

BACKGROUND: Advances in paediatric cardiology have improved the prognosis of children with inherited cardiac disorders. However, health-related quality of life (QoL) and physical activity have been scarcely analysed in children with inherited cardiac arrhythmia or inherited cardiomyopathy. Moreover, current guidelines on the eligibility of young athletes with inherited cardiac disorders for sports participation mainly rely on expert opinions and remain controversial. METHODS: The QUALIMYORYTHM trial is a multicentre observational controlled study. The main objective is to compare the QoL of children aged 6 to 17 years old with inherited cardiac arrhythmia (long QT syndrome, Brugada syndrome, catecholaminergic polymorphic ventricular tachycardia, or arrhythmogenic right ventricular dysplasia), or inherited cardiomyopathy (hypertrophic, dilated, or restrictive cardiomyopathy), to that of age and gender-matched healthy subjects. The secondary objective is to assess their QoL according to the disease's clinical and genetic characteristics, the level of physical activity and motivation for sports, the exercise capacity, and the socio-demographic data. Participants will wear a fitness tracker (ActiGraph GT3X accelerometer) for 2 weeks. A total of 214 children are required to observe a significant difference of 7 ± 15 points in the PedsQL, with a power of 90% and an alpha risk of 5%. DISCUSSION: After focusing on the survival in children with inherited cardiac disorders, current research is expanding to patient-reported outcomes and secondary prevention. The QUALIMYORYTHM trial intends to improve the level of evidence for future guidelines on sports eligibility in this population. Trial registration ClinicalTrials.gov Identifier: NCT04712136, registered on January 15th, 2021 ( https://clinicaltrials.gov/ct2/show/NCT04712136 ).

Dystrophin Deficiency Causes Progressive Depletion of Cardiovascular Progenitor Cells in the Heart.

Duchenne muscular dystrophy (DMD) is a devastating condition shortening the lifespan of young men. DMD patients suffer from age-related dilated cardiomyopathy (DCM) that leads to heart failure. Several molecular mechanisms leading to cardiomyocyte death in DMD have been described. However, the pathological progression of DMD-associated DCM remains unclear. In skeletal muscle, a dramatic decrease in stem cells, so-called satellite cells, has been shown in DMD patients. Whether similar dysfunction occurs with cardiac muscle cardiovascular progenitor cells (CVPCs) in DMD remains to be explored. We hypothesized that the number of CVPCs decreases in the dystrophin-deficient heart with age and disease state, contributing to DCM progression. We used the dystrophin-deficient mouse model (mdx) to investigate age-dependent CVPC properties. Using quantitative PCR, flow cytometry, speckle tracking echocardiography, and immunofluorescence, we revealed that young mdx mice exhibit elevated CVPCs. We observed a rapid age-related CVPC depletion, coinciding with the progressive onset of cardiac dysfunction. Moreover, mdx CVPCs displayed increased DNA damage, suggesting impaired cardiac muscle homeostasis. Overall, our results identify the early recruitment of CVPCs in dystrophic hearts and their fast depletion with ageing. This latter depletion may participate in the fibrosis development and the acceleration onset of the cardiomyopathy.

Impact of a transition education program on health-related quality of life in pediatric patients with congenital heart disease: study design for a randomised controlled trial.

BACKGROUND: Recent advances in the field of congenital heart disease (CHD) led to an improved prognosis of the patients and in consequence the growth of a new population: the grown up with congenital heart disease. Until recently, more than 50% of these patients were lost to follow up because of the lack of specialized structures. The critical moment is the transition between paediatric and adult unit. Therapeutic education is crucial to solve this issue by helping patients to become independent and responsible. The TRANSITION-CHD randomized trial aims to assess the impact of a transition education program on health-related quality of life (HRQoL) of adolescents and young adults with CHD. METHODS: Multicentre, randomised, controlled, parallel arm study in CHD patients aged from 13 to 25 years old. Patients will be randomised into 2 groups (education program vs. no intervention). The primary outcome is the change in self-reported HRQoL between baseline and 12-month follow-up. A total of 100 patients in each group is required to observe a significant increase of the overall HRQoL score of 7 ± 13.5 points (on 100) with a power of 80% and an alpha risk of 5%. The secondary outcomes are: clinical outcomes, cardiopulmonary exercise test parameters (peak VO2, VAT, VE/VCO2 slope), level of knowledge of the disease using the Leuven knowledge questionnaire for CHD, physical and psychological status. DISCUSSION: As the current research is opening on patient related outcomes, and as the level of proof in therapeutic education is still low, we sought to assess the efficacy of a therapeutic education program on HRQoL of CHD patients with a randomized trial. TRIAL REGISTRATION: This study was approved by the National Ethics Committee (South-Mediterranean IV 2016-A01681-50) and was registered on Clinicaltrials.gov (NCT03005626).

Clinical Impact of Autologous Cell Therapy on Hypoplastic Left Heart Syndrome After Bidirectional Cavopulmonary Anastomosis.

Preservation of right ventricle function (RV) is a key to favorable outcome in Hypoplastic Left Heart Syndrome (HLHS), but methods to preserve or improve RV function are limited. Our goal was to assess the clinical and functional impact of autologous umbilical cord blood-derived mononuclear cells (UCB-MNC) therapy when given to patients with HLHS at Stage II surgery. UCB-MNC patients were enrolled prospectively in a phase I, FDA monitored trial as previously described (Burkhart et al., 2019). Matched retrospective controls were identified by review of clinical databases. Growth and RV echocardiographic variables were assessed in both groups prestage II through the first 6 months postoperatively. Statistical comparisons between the groups at similar postoperative time points were made to define potential impact of the cell therapy. There were 7 UCB-MNC patients and 17 controls. Prestage II, most parameters showed no differences between groups, although median fractional area change (FAC) was slightly greater in the controls (FAC: controls = 45% vs UCB-MNC = 41% P= 0.02). At dismissal, FAC and estimated Ejection Fraction (EF) decreased in controls, while both were unchanged from baseline in UCB-MNC patients (ΔFAC: -5% vs -1%, P < 0.01; ΔEF: -8% vs 0%, P = 0.03, respectively). Subsequently, median FAC increased slightly in UCB-MNC patients over the 6 month follow-up period, while it decreased in controls (ΔFAC: UCB-MNC +3% vs control -5%, P = 0.03). Preoperative weight percentiles were similar in both groups (UCB-MNC 34%ile vs controls 22%ile, P = 0.93). However, by 6 months postoperative, median weight percentile improved to 63% in the UCB-MNC treated group, but declined to 8% in controls (P = 0.02). UCB-MNC therapy appears to limit the initial negative impact on RV FAC and EF seen after stage II surgery. During early follow up, FAC and weight percentile improved in UCB-MNC patients relative to controls, suggesting a beneficial effect of UCB-MNC therapy.