The Ross classification for heart failure in children after 25 years: a review and an age-stratified revision

Phenotypic expression, genotypic profiling and clinical outcomes of infantile hypertrophic cardiomyopathy: a retrospective study

BACKGROUND

Infantile hypertrophic cardiomyopathy (HCM) is a heterogeneous disorder. Apart from registries in high-income nations, there is a shortage of data on the aetiological basis of infantile HCM in low- and middle-income nations. This study attempts to characterise the phenotypic expression, genetic architecture and short-term clinical outcomes of infantile HCM from a South Asian tertiary referral centre.

METHODS

This study includes all infants from the Amrita HCM cohort between January 2011 and July 2021. Clinical history, ECG, echocardiographic data, and genetic analyses were evaluated.

RESULTS

34 patients with infantile HCM were diagnosed at a median age of 3.7 months (IQR 1-6 months). Underlying aetiologies were RASopathy (n=13; 38%), non-syndromic (n=12; 35%) and inborn errors of metabolism (n=9; 27%). Genetic analysis was done in 20 patients (59%) with a yield of 90%. Clinical presentation included failure to thrive (n=29; 85%), dyspnoea on exertion (n=23; 68%) and clinical heart failure (n=24; 71%). Echo showed concentric left ventricular hypertrophy in 22 patients (65%), obstructive HCM in 11 patients (32%) and left ventricular systolic dysfunction in 6 patients (18%). The mortality rate was 10.0 deaths per 100 patient years over a median follow-up period of 3.1 years. The main risk markers for mortality were the age at diagnosis, gender and concentric Left ventricular hypertrophy.

CONCLUSIONS

This cohort demonstrates the morphological, functional and genetical heterogeneity of infantile HCM, enunciating the need for integration of cardiology, metabolic and genetic services to achieve optimum outcomes in these patients.

The CHD severity classification system: development of a tool to assist with disease stratification for CHD research

BACKGROUND

Complexity stratification for CHD is an integral part of clinical research due to its heterogenous clinical presentation and outcomes. To support our ongoing research efforts into CHD requiring disease severity stratifications, a simplified CHD severity classification system was developed and verified, with potential utility for clinical researchers without specialist CHD knowledge or access to clinical/medical records.

METHOD

A two-tiered analysis approach was undertaken. First-tier analysis included the audit of a comprehensive system based on: i) timing of intervention, ii) cardiac morphology, and iii) cardiovascular physiology using real patient data (n = 30), across 10 common CHD lesions. Second-tier analysis allowed for a simplified version of the classification system using morphology as a stand-alone predictor. Twelve clinicians of varying specialities involved in CHD care ranked 10 common lesions from least to most severe based on typical presentation and clinical course.

RESULTS

First-tier analysis identified that cardiac morphology was the principal driver of complexity. Second-tier analysis largely confirmed the ranking and classification of the lesions into the broad CHD severity groups, although some variation was noted, specifically among non-cardiac specialists. This simplified version of the classicisation system, with morphology as a stand-alone predictor of severity, allowed for effective stratification for the purposes of analysis.

CONCLUSION

The findings presented here support this comprehensive and simple CHD severity classification system with broad utility in CHD research, particularly among clinicians and researchers with limited knowledge of CHD. The model may be applied to produce locally relevant research tools.

Intrinsic cardiomyopathy in pediatric Marfan syndrome: predictive factors and risk assessments

BACKGROUND

Marfan syndrome (MFS) is associated with cardiovascular complications, particularly valvulopathies; however, its association with primary cardiomyopathy remains unclear.

METHODS

This retrospective cohort study examined the cardiomyopathy characteristics (CMCs) in pediatric patients with MFS. CMCs were defined as meeting at least one of the following echocardiography or clinical parameters: (1) cardiac index (CI) too low for patient's age, (2) ejection fraction (EF) <50%, and (3) diastolic dysfunction. The predictive factors for CMCs were determined using a multivariable logistic regression model.

RESULTS

Among 83 patients with MFS (age, median [range], 12.5 [0.4-22.3] years), 39.8% exhibited CMCs. Only 4 patients (5%) showed heart failure symptoms (NYHA > 1). Independent predictors for CMCs included a systemic score of ≥7 (revised Ghent criteria) and likely pathogenic or pathogenic variants in FBN1, including variants that introduce a premature stop codon, splice site variants, and missense variants involving cysteine. A multivariable score was constructed with an AUC of 0.733.

CONCLUSION

This study offers valuable insights into the prevalence and predictors of CMC in pediatric patients with MFS and presents potential strategies for risk assessment of cardiomyopathy.

IMPACT

The objective of this study was to elucidate the contentious issue of intrinsic cardiomyopathy in Marfan syndrome and demonstrate its notable occurrence even in pediatric patients who do not exhibit heart failure symptoms or valvular complications. We highlighted the importance of specific FBN1 variants and higher systemic scores in identifying the potential for intrinsic cardiomyopathy in pediatric patients with Marfan syndrome.

Advances in understanding and managing pediatric heart failure and transplant

PURPOSE OF REVIEW

This article highlights the most recent advances in a review of the current literature in the field of pediatric heart failure and transplantation.

RECENT FINDINGS

Diagnostically, the identification of new genetic factors has contributed to a deeper understanding of cardiomyopathy in children. Novel medications like sacubitril/valsartan and Sodium-Glucose cotransporter-2 (SGLT2) inhibitors, which are now standard in the adult population are being studied in pediatric population and offer new promise of pediatric heart failure treatment. Ventricular assist devices are more commonly used in cardiomyopathy patients and single ventricle patients as a bridge to transplant. Recent pediatric heart transplant society (PHTS) data demonstrated that waitlist survival improved significantly over the past decades (i) and new treatments such as daratumumab and eculizumab have been used in high-risk populations and demonstrate promising results. TEAMMATE trial is the first multicenter randomized clinical trial (RCT) in pediatric heart transplant (HT) to evaluate the safety and efficacy of everolimus (EVL) and low-dose tacrolimus (TAC) compared to standard-dose TAC and mycophenolate mofetil (MMF). It will provide valuable information about the safety and efficacy of EVL, TAC, and MMF (ii).Donor cell-free DNA has been used more in pediatric transplant recipients and has significantly decreased invasive EMB (iii).

SUMMARY

This past 5 years have witness dramatic progress in the field of pediatric heart failure and transplantation including more use of mechanical support in heart failure patients with various underlying etiology, especially use of mechanical support in single ventricle patients and the use of sacubitril/valsartan and SGLT2 inhibitors in the pediatric population. The problem of the highly sensitized transplant recipient remains, although novel therapeutics have been added to our toolbox of options to maintain healthy allograft function. Ongoing research aims to further enhance our understanding and management of pediatric heart failure, emphasizing the need for continued innovation in this complex field.

Clinical and Hemodynamic Outcomes with Enalapril Orodispersible Minitablets in Young Children with Heart Failure Due to Congenital Heart Disease

Background: The angiotensin-converting enzyme inhibitor (ACEI) enalapril is often administered to infants and young children with heart failure (HF) in various dosing regimens and formulations not adapted for their age. Methods: This prospective, two-center, open-label 8-week study evaluated an age-appropriate formulation of orodispersible minitablets (ODMTs) of enalapril (0.25 mg and 1 mg) in children aged 0 to 6 years with HF due to congenital heart disease. An age/weight-based dosing schedule was followed. Measures of echocardiographic parameters, blood pressure, heart rate, modified Ross score, and biochemistry were obtained over the 8-week period. The following two groups were assessed: ACEI-naïve and ACEI-pretreated patients. Results: In total, 53 children (age range of 0.05 to 4.8 years) were enrolled and 29 were ACEI-naïve. The average enalapril dose was 0.098 mg/kg (0.06-0.17 mg/kg) in the naïve group and 0.15 mg/kg (0.07-0.3 mg/kg) in pretreated patients. After 8 weeks, the modified Ross score and left ventricular diastolic dimension (LVD) z-score showed a significant decrease in both groups (p < 0.005). During 8 weeks follow-up, there were no difference in the z-scores for the systolic blood pressure (p = 0.071) or heart rate (p = 0.146). Conclusions: Pediatric patients treated with ODMTs of enalapril for 8 weeks had favorable improvements in LVD and HF symptoms.

A Review of Contemporary and Future Pharmacotherapy for Chronic Heart Failure in Children

This review delves into the most recent therapeutic approaches for pediatric chronic heart failure (HF) as proposed by the International Society for Heart and Lung Transplantation (ISHLT), which are not yet publicly available. The guideline proposes an exhaustive overview of the evolving pharmacological strategies that are transforming the management of HF in the pediatric population. The ISHLT guidelines recognize the scarcity of randomized clinical trials in children, leading to a predominance of consensus-based recommendations, designated as Level C evidence. This review article aims to shed light on the significant paradigm shifts in the proposed 2024 ISHLT guidelines for pediatric HF and their clinical ramifications for pediatric cardiology practitioners. Noteworthy advancements in the updated proposed guidelines include the endorsement of angiotensin receptor-neprilysin inhibitors (ARNIs), sodium-glucose cotransporter 2 inhibitors (SGLT2is), and soluble guanylate cyclase (sGC) stimulators for treating chronic HF with reduced ejection fraction (HFrEF) in children. These cutting-edge treatments show potential for enhancing outcomes in pediatric HFrEF. Nonetheless, the challenge persists in validating the efficacy of therapies proven in adult HFrEF for the pediatric cohort. Furthermore, the proposed ISHLT guidelines address the pharmacological management of chronic HF with preserved ejection fraction (HFpEF) in children, marking a significant step forward in pediatric HF care. This review also discusses the future HF drugs in the pipeline, their mechanism of actions, potential uses, and side effects.

Evaluation and Management of Chronic Heart Failure in Children and Adolescents With Congenital Heart Disease: A Scientific Statement From the American Heart Association

With continued medical and surgical advancements, most children and adolescents with congenital heart disease are expected to survive to adulthood. Chronic heart failure is increasingly being recognized as a major contributor to ongoing morbidity and mortality in this population as it ages, and treatment strategies to prevent and treat heart failure in the pediatric population are needed. In addition to primary myocardial dysfunction, anatomical and pathophysiological abnormalities specific to various congenital heart disease lesions contribute to the development of heart failure and affect potential strategies commonly used to treat adult patients with heart failure. This scientific statement highlights the significant knowledge gaps in understanding the epidemiology, pathophysiology, staging, and outcomes of chronic heart failure in children and adolescents with congenital heart disease not amenable to catheter-based or surgical interventions. Efforts to harmonize the definitions, staging, follow-up, and approach to heart failure in children with congenital heart disease are critical to enable the conduct of rigorous scientific studies to advance our understanding of the actual burden of heart failure in this population and to allow the development of evidence-based heart failure therapies that can improve outcomes for this high-risk cohort.

Weight gain in infants with congenital heart disease; breastfeeding alone versus supplemental spoon-feeding of expressed breast milk: an open-label, pilot, randomised control trial

OBJECTIVES

Infants with congenital heart disease and increased pulmonary blood flow frequently suffer from feeding difficulties and growth failure. Providing expressed breast milk by spoon has been hypothesised to decrease energy expenditure in these infants as compared to breastfeeding. This study assessed the effect of supplemental feeding of expressed breast milk on weight gain in infants with unoperated congenital heart disease.

METHOD

This was a prospective open-label randomised control trial. In total, 50 infants with post tricuspid left to right shunt were enrolled in the study. In the intervention group, apart from breastfeeding, a minimum predetermined volume of expressed breast milk was targeted to be given by spoon. 30-50 kcal/kg/day was given by expressed breast milk by spoon-feeding. In the control group, the infants were given at least 8 feeds per 24 hours by direct breastfeeding. Both groups were followed up for 1 month and assessed for weight gain.

RESULT

Despite a high rate of protocol breach in both groups (30% overall), infants in the intervention group had better weight gain at one-month follow-up compared to those in the control group, 780 ± 300 versus 530 ± 250 gm (p = 0.01).

CONCLUSION

In infants with left to right shunts, supplemental feeding of expressed breast milk by spoon along with breastfeeding resulted in significantly higher average weight gain at 30 days compared to the control group who received breastfeeding alone. Future studies with larger sample sizes and longer follow-ups need to be done to confirm the findings of this study.

High-sensitive troponinT, interleukin-8, and interleukin-6 link with post-surgery risk in infant heart surgery

BACKGROUND

This study focuses on biomarkers in infants after open heart surgery, and examines the association of high-sensitive troponin T (hs-cTnT), interleukin-6 (IL-6), and interleukin-8 (IL-8) with postoperative acute kidney injury (AKI), ventilatory support time and need of vasoactive drugs.

METHODS

Secondary exploratory study from a double-blinded clinical randomized trial (Mile-1) on 70 infants undergoing open heart surgery with cardiopulmonary bypass (CPB). In this sub-study, the entire study population was examined without considering the study drugs. The biomarkers' peak concentration (highest concentration at 2 or 6 h post-CPB) were used for statistical analyses.

RESULTS

Peak IL-8, hs-cTnT, and IL-6 occurred at 2 h post-CPB for 96%, 79%, and 63% of the patients, respectively. The odds ratio of developing AKI2-3 for IL-6 > 293 pg/mL was 23.4 (95% CI 5.3;104.0), for IL-8 > 100 pg/mL it was 11.5 (3.0;44.2), and for hs-cTnT >5597 pg/mL it was 6.1 (1.5; 24.5). In more than two third of the patients with the highest peak concentrations of IL-8, IL-6, and hs-cTnT, there was a need for ventilatory support for >24 h and use of vasoactive drugs at 24 h post-CPB, while in less than one third of the patients with the lowest peak concentrations of IL-8 and hs-cTnT such requirements were observed.

CONCLUSIONS

The peak biomarker concentrations and CPB-time strongly predicted AKI2-3, with IL-6 and IL-8 emerging as strongest predictors. Furthermore, our findings suggest that measuring hs-cTnT and IL-8 just 2 h post-CPB-weaning may assist in identifying infants suitable for early extubation and highlight those at risk of prolonged ventilation.

Direct comparison of the diagnostic performance of growth differentiation factor 8 in pediatric versus adult heart failure

INTRODUCTION

Growth differentiation factor 8 (GDF-8, myostatin) has been proposed for the management of adult heart failure (HF). Its potential role in pediatric HF patients is unknown. We sought to investigate its diagnostic performance in adult versus pediatric HF.

METHODS

GDF-8 was measured prospectively in pediatric and adult HF patients and in matching controls. HF was defined as the combination of typical symptoms and impaired left ventricular systolic function. Diagnostic performance for the detection of HF was evaluated by receiver operating characteristic (ROC) analysis.

RESULTS

We enrolled 137 patients with HF (85 pediatric) and 67 healthy controls (47 pediatric). Neither pediatric nor adult HF patients had significantly different GDF-8 levels compared to the reference groups (3.53 vs 3.46 ng/mL, p = 0.334, and 6.87 vs 8.15 ng/mL, p = 0.063, respectively), but pediatric HF patients had significantly lower GDF-8 levels compared to adult patients (p < 0.001). ROC analysis showed no significant improvement adding GDF-8 to NT-proBNP, age and sex (area under the curve (AUC): 0.870 vs 0.868, p = 0.614) in children and neither in addition to age nor sex in adult HF patients (AUC: 0.74 vs 0.62, p = 0.110).

CONCLUSION

GDF-8 did not accurately differentiate between HF patients and normal comparators in neither adults nor in children.

Use of echocardiography in percutaneous closure of patent ductus arteriosus at the Instituto Nacional de Salud del Niño, San Borja, Lima - Peru

Objetive

Percutaneous occlusion of patent ductus arteriosus (PDA) has classically been performed entirely by fluoroscopy, however in recent years, transthoracic echocardiography (TE) has been used as an aid to fluoroscopy or entirely by echocardiography, which avoids access of femoral artery, use of contrast and decrease in time and dose of radiation exposure. The objective of this study was to evaluate the success rate with the use of TE in percutaneous PDA closure.

Material and method

Descriptive, comparative, retrospective study between patients in whom PDA closure was performed with fluoroscopy plus angiography (group 1) and fluoroscopy plus ET (group 2), between January 2018 and December 2022. The data were obtained from the clinical history electronic and procedure report.

Results

One hundred eight patients were analyzed, fluoroscopy group (n: 57) and TE (n: 51). The success rate in PDA occlusion using TE was 100% and 98% for the fluoroscopy group, with no statistically significant difference The average age of group 2 was 2.9 years, while the average age of group 1 was 5 years (p=0.001), the average fluoroscopy time in group 1 was 16.9 min and 4.71 min in group 2 (p < 0.001); the fluoroscopy dose in group 1 was 68.98 mGy and 5.17 mGy in group 2 (p<0.001). Krichenko, but without significant difference in both groups.

Conclusions

The success rate of percutaneous PDA closure using echocardiography and fluoroscopy is appropiate, with a success rate similar to the classic technique. In addition, it makes it possible to reduce the dose and time of fluoroscopy, avoid the use of contrast, and access the femoral artery.

Outcomes of not using tracheoplasty in asymptomatic tracheal stenosis found during open-heart surgery

OBJECTIVES

We aimed to review the outcomes of treating incidentally encountered asymptomatic airway stenosis during open-heart surgery conservatively without the use of tracheoplasty.

METHODS

Between January 2002 and October 2022, 25 patients were incidentally diagnosed with tracheal stenosis during open-heart surgery. Intraoperative bronchoscopy and/or laryngoscopy revealed tracheal stenosis; however, this was not consistent with the findings of the preoperative computed tomography. Patients who were diagnosed with a pulmonary artery or vascular sling or had moderate-to-severe respiratory symptoms before open-heart surgery were excluded.

RESULTS

The median age and weight of the patients at operation were 3.0 months and 5.1 kg, respectively. They were categorized as those having tracheal stenosis on preoperative computed tomography (n = 12) or not having tracheal stenosis (n = 13). The narrowest diameter was significantly smaller in the former group (3.0 vs 5.8 mm, P < 0.05). The rates of reintubation and the tracheostomy, and intubation days tended to be higher in former group without statistical significance. Stenotic degree improved 2 months and 1 year or more after the operation (39.3% at operation, 28.4% at 2 months, 12.5% after 1 year). All patients were Ross class 1 or 2 at follow-up (mean, 7.1 years).

CONCLUSIONS

Patients with tracheal stenosis showed tolerable long-term outcomes without using tracheoplasty. Accordingly, if tracheal stenosis, that would cause intubation difficulty, was incidentally revealed, concomitant tracheoplasty may not be required during open-heart surgery if the stenosis did not cause considerable symptoms or signs preoperatively.

Effects of 6-month customized home-based exercise on motor development, bone strength, and parental stress in children with simple congenital heart disease: a single-blinded randomized clinical trial

BACKGROUND

New "noncardiac" problems in children with congenital heart disease (CHD), such as developmental delay or long-term neurodevelopmental impairments, have attracted considerable attention in recent years. It is hypothesized that exercise might attenuate CHD-associated neurodevelopmental impairments; however, this has not been thoroughly investigated. The objective of this prospective, single-blinded, randomized controlled experiment was to evaluate the impact of customized home-based exercise for children with CHD.

METHODS

Children aged 0-5 years with echocardiography-confirmed simple CHD subtypes who were scheduled to undergo cardiac catheterization were screened for enrolment. Among 420 screened CHD children, 192 were enrolled and randomly assigned at a 1:1 ratio to receive a 6-month intervention (30 min daily customized home-based exercise program with supervision for no less than 5 days per week, combined with home-based exercise education) or control treatment (home-based education). The primary outcome was motor development (gross motor quotient (GMQ), fine motor quotient (FMQ), and total motor quotient (TMQ)). The secondary outcomes were cardiac function and structure, bone quality, physical development, parental anxiety, caregiver burden, and quality of life. Children and their families were assessed before and 1, 3, and 6 months after catheterization; 183 (95.3%) children were included in the primary analysis.

RESULTS

After 6-month treatment, the intervention group significantly increased their motor quotient, which was consistently higher than that of the control group (GMQ p < 0.0001, FMQ p = 0.02, TMQ p < 0.001). The physical developments in height, weight, and circumferences of the upper-arm, chest, and head were also significantly improved by exercise (all p < 0.017). No significant improvements in the bone strength or the cardiac structure and function were found among patients in the intervention group (all p > 0.017). For parents, higher quality of life level (total score p = 0.016) was observed in the intervention group; while effects of exercise on the anxiety (rude score p = 0.159, standard score p = 0.159) or the Zarit caregiver burden scale score (p = 0.404) were non-significant. No adverse events occurred during the study period.

CONCLUSIONS

Customized home-based exercise improved motor development in children with CHD. While the long-term effects of parent training in home-based exercise are unknown, the study results suggest positive outcomes.

TRIAL REGISTRATION

A home-based exercise program in congenital heart disease children with cardiac catheterization: a randomized controlled trial. ( http://www.chictr.org.cn/ , ChiCTR-IOR-16007762, January 14, 2016).

Association of albuminuria with kidney function and hemodynamic disturbance in pre-school children who undergo congenital heart disease surgery

BACKGROUND

We validated the prevalence of albuminuria and its association with kidney function and hemodynamics in pre-school children who underwent surgery for congenital heart disease (CHD).

METHODS

From 403 patients who had undergone surgery for CHD at least 6 months before pre-school and were admitted to our hospital between 2011 and 2015, 75 who underwent blood and urine tests and cardiac catheterization were included in this study. The urinary albumin-to-creatinine ratio (ACR) was quantified, and the relationship of ACR with physical and laboratory findings and hemodynamics assessed using cardiac catheterization was analyzed.

RESULTS

The study cohort was divided into three groups: Fontan group (n = 25), tetralogy of Fallot (TOF) group (n = 18), and control group (other biventricular CHDs; n = 32). The median age of patients was 5.9 years. ACR was higher in the Fontan group than in the TOF and control groups (median: 15.0 vs. 5.0 and 0.0 mg/g, p < 0.001). Moreover, albuminuria (ACR > 30 mg/g) was observed in 20.0% of Fontan patients, while ACR was associated with potential complicating factors of Fontan circulation: high central venous pressure, high mean pulmonary artery pressure, and worse than moderate atrioventricular regurgitation. ACR showed a moderate correlation with the cystatin C-based estimated glomerular filtration rate (r =  - 0.725, p < 0.001).

CONCLUSIONS

Measurement of albuminuria in Fontan patients before they join elementary school is useful because it reflects kidney function and hemodynamic factors that can worsen their condition. Identification and management of patients with albuminuria may facilitate early therapeutic intervention for worsening Fontan factors, eventually delaying the deterioration of kidney function. A higher resolution version of the Graphical abstract is available as Supplementary information.

Long-term surgical outcomes of congenital supravalvular aortic stenosis: a systematic review, meta-analysis and microsimulation study

OBJECTIVES

Congenital supravalvular aortic stenosis (SVAS) is a rare form of congenital outflow tract obstruction and long-term outcomes are scarcely reported. This study aims to provide an overview of outcomes after surgical repair for congenital SVAS.

METHODS

A systematic review of published literature was conducted, including observational studies reporting long-term clinical outcome (>2 years) after SVAS repair in children or adults considering >20 patients. Early risks, late event rates and time-to-event data were pooled and entered into a microsimulation model to estimate 30-year outcomes. Life expectancy was compared to the age-, sex- and origin-matched general population.

RESULTS

Twenty-three publications were included, encompassing a total of 1472 patients (13 125 patient-years; pooled mean follow-up: 9.0 (6.2) years; median follow-up: 6.3 years). Pooled mean age at surgical repair was 4.7 (5.8) years and the most commonly used surgical technique was the single-patch repair (43.6%). Pooled early mortality was 4.2% (95% confidence interval: 3.2-5.5%) and late mortality was 0.61% (95% CI: 0.45-0.83) per patient-year. Based on microsimulation, over a 30-year time horizon, it was estimated that an average patient with SVAS repair (mean age: 4.7 years) had an observed life expectancy that was 90.7% (95% credible interval: 90.0-91.6%) of expected life expectancy in the matched general population. The microsimulation-based 30-year risk of myocardial infarction was 8.1% (95% credible interval: 7.3-9.9%) and reintervention 31.3% (95% credible interval: 29.6-33.4%), of which 27.2% (95% credible interval: 25.8-29.1) due to repair dysfunction.

CONCLUSIONS

After surgical repair for SVAS, 30-year survival is lower than the matched-general-population survival and the lifetime risk of reintervention is considerable. Therefore, lifelong monitoring of the cardiovascular system and in particular residual stenosis and coronary obstruction is recommended.

Multicenter Study of Survival Benefit of Cardiac Resynchronization Therapy in Pediatric and Congenital Heart Disease

BACKGROUND

Evidence for the efficacy of cardiac resynchronization therapy (CRT) in pediatric and congenital heart disease (CHD) has been limited to surrogate outcomes.

OBJECTIVES

This study aimed to assess the impact of CRT upon the risk of transplantation or death in a retrospective, high-risk, controlled cohort at 5 quaternary referral centers.

METHODS

Both CRT patients and control patients were <21 years of age or had CHD; had systemic ventricular ejection fraction <45%; symptomatic heart failure; and significant electrical dyssynchrony (QRS duration z score >3 or single-site ventricular pacing >40%) at enrollment. Patients with CRT were matched with control patients via 1:1 propensity score matching. CRT patients were enrolled at CRT implantation; control patients were enrolled at the outpatient clinical encounter where inclusion criteria were first met. The primary endpoint was transplantation or death.

RESULTS

In total, 324 control patients and 167 CRT recipients were identified. Mean follow-up was 4.2 ± 3.7 years. Upon propensity score matching, 139 closely matched pairs were identified (20 baseline indices). Of the 139 matched pairs, 52 (37.0%) control patients and 31 (22.0%) CRT recipients reached the primary endpoint. On both unadjusted and multivariable Cox regression analysis, the risk reduction associated with CRT for the primary endpoint was significant (HR: 0.40; 95% CI: 0.25-0.64; P < 0.001; and HR: 0.44; 95% CI: 0.28-0.71; P = 0.001, respectively). On longitudinal assessment, the CRT group had significantly improved systemic ventricular ejection fraction (P < 0.001) and shorter QRS duration (P = 0.015), sustained to 5 years.

CONCLUSIONS

In pediatric and CHD patients with symptomatic systolic heart failure and electrical dyssynchrony, CRT was associated with improved heart transplantation-free survival.

Sudden cardiac death in childhood RASopathy-associated hypertrophic cardiomyopathy: Validation of the HCM risk-kids model and predictors of events

BACKGROUND

RASopathies account for nearly 20% of cases of childhood hypertrophic cardiomyopathy (HCM). Sudden cardiac death (SCD) occurs in patients with RASopathy-associated HCM, but the risk factors for SCD have not been systematically evaluated.

AIM

To validate the HCM Risk-Kids SCD risk prediction model in children with RASopathy-associated HCM and investigate potential specific SCD predictors in this population.

METHODS

Validation of HCM Risk-Kids was performed in a retrospective cohort of 169 patients with a RASopathy-associated HCM from 15 international paediatric cardiology centres. Multiple imputation by chained equations was used for missing values related to the HCM Risk-Kids parameters.

RESULTS

Eleven patients (6.5%) experienced a SCD or equivalent event at a median age of 12.5 months (IQR 7.7-28.64). The calculated SCD/equivalent event incidence was 0.78 (95% CI 0.43-1.41) per 100 patient years. Six patients (54.54%) with an event were in the low-risk category according to the HCM Risk-Kids model. Harrell's C index was 0.60, with a sensitivity of 9.09%, specificity of 63.92%, positive predictive value of 1.72%, and negative predictive value of 91%; with a poor distinction between the different risk groups. Unexplained syncope (HR 42.17, 95% CI 10.49-169.56, p < 0.001) and non-sustained ventricular tachycardia (HR 5.48, 95% CI 1.58-19.03, p < 0.007) were predictors of SCD on univariate analysis.

CONCLUSION

Unexplained syncope and the presence of NSVT emerge as predictors for SCD in children with RASopathy-associated HCM. The HCM Risk-Kids model may not be appropriate to use in this population, but larger multicentre collaborative studies are required to investigate this further.

Rediscover the predictive capacity of B-type natriuretic peptide applied to neonatal supraventricular tachycardia

BACKGROUND

Supraventricular tachycardia (SVT) is one of the most common non-benign arrhythmias in neonates, potentially leading to cardiac decompensation. This study investigated the early risk factors of acute heart failure (AHF) secondary to SVT in neonates, and explored their value in guiding the selection of effective anti-arrhythmic treatment.

METHODS

A total of 43 newborns diagnosed with and treated for SVT between January 2017 and December 2022 were analyzed. According to the presence of AHF after restoring sinus rhythm in newborns with SVT, they were divided into SVT with AHF group and SVT without AHF group. Clinical data and anti-arrhythmic therapies were analyzed. Risk factors of AHF secondary to SVT in neonates were determined using logistic regression. The cut-off value for predictors of AHF secondary to SVT and demanding of a second-line anti-arrhythmic treatment was determined through receiver operating characteristic (ROC) analysis.

RESULTS

Time to initial control of tachycardia > 24 h, hyperkalemia, anemia, and plasma B-type natriuretic peptide (BNP) were identified as risk factors of AHF secondary to SVT in neonates. BNP exhibited AUC of 0.80 in predicting AHF, and BNP > 2460.5pg/ml (OR 2.28, 95% CI 1.27 ~ 45.39, P = 0.03) was an independent predictor, yielding sensitivity of 70.6% and specificity of 84.6%. Neonates with BNP > 2460.5pg/ml (37.5% versus 7.4%, P = 0.04) had a higher demand for a second line anti-arrhythmic treatment to terminate SVT, with sensitivity and specificity for BNP in predicting at 75.0%, 71.4%, respectively.

CONCLUSIONS

BNP could be used to predict an incident of AHF secondary to SVT and a demand of second-line anti-arrhythmic treatment to promptly terminate SVT and prevent decompensation in neonates.

Open Field Exercise Testing in Pediatric Congenital Heart Disease Patients: A Subsumption of Cardiovascular Parameters

Heart failure is a common phenomenon in congenital heart disease patients. Cardiopulmonary exercise testing is used for a reliable assessment of heart failure but is still challenging, especially for young children. Implementing mobile cardiopulmonary exercise testing (CPET) can close that diagnostic gap. While average values for healthy children have already been published, this study aims to describe typical ranges of cardiovascular performance parameters of young children with congenital heart disease performing an 8-min running cardiopulmonary exercise test. Children aged 4-8 years with common congenital heart defects after corrective surgery (Tetralogy of Fallot; transposition of the great arteries and univentricular hearts after palliation) were included. The outdoor running protocol consisted of slow walking, slow jogging, fast jogging, and maximum speed running. Each exercise was performed for 2 min, except the last, in which children were instructed to keep up maximal speed as long as possible. A total of 78 children (45 male/33 female, mean age 6,24) with congenital heart disease participated in the study, of which 97% completed the CPET successfully. A detailed description of participating patients, including data on cardiac function and subjective fitness levels, is given to help physicians use this method to classify their patients. This study presents a typical range for cardiovascular performance parameters in a population of 4-8-year-old children with congenital heart disease tested in a newly developed outdoor running protocol for CPET.

Paediatric aortic valve replacement: a meta-analysis and microsimulation study

AIMS

To support decision-making in children undergoing aortic valve replacement (AVR), by providing a comprehensive overview of published outcomes after paediatric AVR, and microsimulation-based age-specific estimates of outcome with different valve substitutes.

METHODS AND RESULTS

A systematic review of published literature reporting clinical outcome after paediatric AVR (mean age <18 years) published between 1/1/1990 and 11/08/2021 was conducted. Publications reporting outcome after paediatric Ross procedure, mechanical AVR (mAVR), homograft AVR (hAVR), and/or bioprosthetic AVR were considered for inclusion. Early risks (<30d), late event rates (>30d) and time-to-event data were pooled and entered into a microsimulation model. Sixty-eight studies, of which one prospective and 67 retrospective cohort studies, were included, encompassing a total of 5259 patients (37 435 patient-years; median follow-up: 5.9 years; range 1-21 years). Pooled mean age for the Ross procedure, mAVR, and hAVR was 9.2 ± 5.6, 13.0 ± 3.4, and 8.4 ± 5.4 years, respectively. Pooled early mortality for the Ross procedure, mAVR, and hAVR was 3.7% (95% CI, 3.0%-4.7%), 7.0% (5.1%-9.6%), and 10.6% (6.6%-17.0%), respectively, and late mortality rate was 0.5%/year (0.4%-0.7%/year), 1.0%/year (0.6%-1.5%/year), and 1.4%/year (0.8%-2.5%/year), respectively. Microsimulation-based mean life-expectancy in the first 20 years was 18.9 years (18.6-19.1 years) after Ross (relative life-expectancy: 94.8%) and 17.0 years (16.5-17.6 years) after mAVR (relative life-expectancy: 86.3%). Microsimulation-based 20-year risk of aortic valve reintervention was 42.0% (95% CI: 39.6%-44.6%) after Ross and 17.8% (95% CI: 17.0%-19.4%) after mAVR.

CONCLUSION

Results of paediatric AVR are currently suboptimal with substantial mortality especially in the very young with considerable reintervention hazards for all valve substitutes, but the Ross procedure provides a survival benefit over mAVR. Pros and cons of substitutes should be carefully weighed during paediatric valve selection.

Macitentan in the Young-Mid-term Outcomes of Patients with Pulmonary Hypertensive Vascular Disease treated in a Pediatric Tertiary Care Center

BACKGROUND

Pulmonary hypertension (PH) is a severe hemodynamic condition with high morbidity and mortality. Approved targeted therapies are limited for pediatric subjects, and treatments are widely adopted from adult algorithms. Macitentan is a safe and effective drug used for adult PH, but data on pediatric patients are limited. In this prospective single-center study, we investigated mid- and long-term effects of macitentan in children with advanced pulmonary hypertensive vascular disease.

METHODS

Twenty-four patients were enrolled in the study for treatment with macitentan. Efficacy was determined by echo parameters and brain natriuretic peptide levels (BNP) at 3 months and 1 year. For detailed analysis, the entire cohort was subgrouped into patients with congenital heart disease-related PH (CHD-PH) and non-CHD-PH patients, respectively.

RESULTS

Mean age of the patients was 10.7 ± 7.6 years; median observation period was 36 months. Twenty of 24 patients were on additional sildenafil and/or prostacyclins. Two of 24 patients discontinued because of peripheral edema. Within the entire cohort, BNP levels and all echo measures such as right ventricular systolic pressure (RVSP), right ventricular end-diastolic diameter (RVED), tricuspid annular plane systolic excursion (TAPSE), pulmonary velocity time integral (VTI), and pulmonary artery acceleration time (PAAT) improved significantly after 3 months (p ≤ 0.01), whereas in the long term significant improvement persisted for BNP levels (-16%), VTI (+14%) and PAAT (+11%) (p < 0.05). By subgroup analysis, non-CHD PH patients showed significant improvements in BNP levels (-57%) and all echo measures (TAPSE +21%, VTI +13%, PAAT +37%, RVSP -24%, RVED -12%) at 3 months (p ≤ 0.01), whereas at 12 months, improvements persisted (p < 0.05) except for RVSP and RVED (nonsignificant). In CHD-PH patients, none of the measures changed (nonsignificant). 6-MWD (distance walked in 6 minutes) slightly increased but was not statistically evaluated.

CONCLUSION

Data presented herein account for the largest cohort of severely affected pediatric patients receiving macitentan. Overall, macitentan was safe and associated with significant beneficial effects and sustained positive signals after 1 year, albeit in the long term disease progression remains a major concern. Our data suggest limited efficacy in CHD-related PH, whereas favorable outcomes were mainly driven by improvements in patients with PH not related to CHD. Larger studies are needed to verify these preliminary results and to prove efficacy of this drug in different pediatric PH entities.

Elevated Copeptin Levels Are Associated with Heart Failure Severity and Adverse Outcomes in Children with Cardiomyopathy

In children with cardiomyopathy, the severity of heart failure (HF) varies. However, copeptin, which is a biomarker of neurohormonal adaptation in heart failure, has not been studied in these patients. In this study, we evaluated the correlation of copeptin level with functional HF grading, B-type natriuretic peptide (BNP), and echocardiography variables in children with cardiomyopathy. Furthermore, we determined if copeptin levels are associated with adverse outcomes, including cardiac arrest, mechanical circulatory support, heart transplant, or death. In forty-two children with cardiomyopathy with a median (IQR) age of 13.1 years (2.5-17.2) and a median follow-up of 2.5 years (2.2-2.7), seven (16.7%) children had at least one adverse outcome. Copeptin levels were highest in the patients with adverse outcomes, followed by the patients without adverse outcomes, and then the healthy children. The copeptin levels in patients showed a strong correlation with their functional HF grading, BNP level, and left ventricular ejection fraction (LVEF). Patients with copeptin levels higher than the median value of 25 pg/mL had a higher likelihood of experiencing adverse outcomes, as revealed by Kaplan-Meier survival analysis (p = 0.024). Copeptin level was an excellent predictor of outcomes, with an area under the curve of 0.861 (95% CI, 0.634-1.089), a sensitivity of 86%, and a specificity of 60% for copeptin level of 25 pg/mL. This predictive value was superior in patients with dilated and restrictive cardiomyopathies (0.97 (CI 0.927-1.036), p < 0.0001, n = 21) than in those with hypertrophic and LV non-compaction cardiomyopathies (0.60 (CI 0.04-1.16), p = 0.7, n = 21).

Diagnosis and Management of Pediatric Heart Failure

Heart failure is a highly morbid syndrome, recognized as a major cause of adult mortality. Heart failure in pediatric patients, whether in the setting of congenital or acquired heart disease, is similarly associated with high mortality and resource utilization. Understanding the clinical presentation, diagnosis, and initial stabilization of pediatric heart failure is paramount for any acute care clinician as it may mimic common childhood ailments like viral respiratory or gastrointestinal illnesses. Pediatric heart failure occurs in patients with palliated or unpalliated congenital heart disease, familial or acquired cardiomyopathy, acquired valve disease, and myocarditis. This review will focus on heart failure in pediatric patients with structurally normal hearts and will summarize what is known about patterns of presentation, etiologies, diagnostic evaluation, and the acute and chronic management of this highly morbid syndrome.

Fibroblast growth factor 23 in children with or without heart failure: a prospective study

BACKGROUND

Elevated fibroblast growth factor 23 (FGF23) levels have been associated with mortality in adults with heart failure (HF), but data on FGF23 levels in paediatric HF are limited. In this prospective cohort study, we aimed to assess the prognostic value of FGF23 in children with chronic HF.

METHODS

We prospectively enrolled 40 children with chronic HF and 20 matched healthy controls. In each patient, a complete diagnostic workup was performed, including transthoracic echocardiography to evaluate cardiac systolic and diastolic functions. Serum FGF23, renal function tests, parathyroid hormone, serum calcium and phosphate were measured in patients and controls. N-terminal probrain natriuretic peptide (NT-proBNP) was measured in patients. The severity of symptoms was assessed using the modified Ross HF classification for children. Patients were followed for 1 year, and clinical worsening events such as death and HF hospitalisation were recorded.

RESULTS

Patients with HF had significantly higher FGF23 levels compared with controls (355.68±97.27 pg/mL and 60.20±11.04 pg/mL, respectively; p<0.001). Three patients died and 11 were admitted with HF. In comparison with patients without clinical worsening events, these 14 patients exhibited significantly higher FGF23 levels (320.04±89.56 pg/mL and 421.86±75.50 pg/mL, respectively; p<0.001). FGF23 was positively correlated with NT-proBNP and left ventricular end-diastolic diameter and negatively correlated with ejection fraction and fractional shortening. The ability of FGF23 to predict clinical worsening events in patients was analysed using a receiver operating characteristic curve. The optimal cut-off point was 375 pg/mL, with 85.71% sensitivity, 84.62% specificity, positive predictive value of 75.0, negative predictive value of 91.7 and area under the curve (AUC) of 0.878. Multivariable regression analysis revealed that FGF23 is the only independent predictor of clinical worsening events in children with chronic HF.

CONCLUSION

FGF23 levels were elevated in children with chronic HF and increased significantly as Ross score class increased. FGF23 levels increased in patients who experienced clinical worsening events.

Elevated cardiac biomarkers and outcomes in children and adolescents with acute COVID-19

Cardiac involvement associated with multi-system inflammatory syndrome in children has been extensively reported, but the prevalence of cardiac involvement in children with SARS-CoV-2 infection in the absence of inflammatory syndrome has not been well described. In this retrospective, single centre, cohort study, we describe the cardiac involvement found in this population and report on outcomes of patients with and without elevated cardiac biomarkers. Those with multi-system inflammatory syndrome in children, cardiomyopathy, or complex CHD were excluded. Inclusion criteriaz were met by 80 patients during the initial peak of the pandemic at our institution. High-sensitivity troponin T and/or N-terminal pro-brain type natriuretic peptide were measured in 27/80 (34%) patients and abnormalities were present in 5/27 (19%), all of whom had underlying comorbidities. Advanced respiratory support was required in all patients with elevated cardiac biomarkers. Electrocardiographic abnormalities were identified in 14/38 (37%) studies. Echocardiograms were performed on 7/80 patients, and none demonstrated left ventricular dysfunction. Larger studies to determine the true extent of cardiac involvement in children with COVID-19 would be useful to guide recommendations for standard workup and management.

The value of modified Ross score in the evaluation of children with severe lower respiratory tract infection admitted to the pediatric intensive care unit

Heart failure (HF) represents an important cause of morbidity and mortality in children. It is mostly caused by congenital heart disease (CHD) and cardiomyopathy. The Ross HF classification was developed to assess severity in infants and has subsequently been modified to apply to all pediatric ages. The modified Ross classification for children provides a numeric score comparable with the New York Heart Association (NYHA) HF classification for adults. The aim of this work is to investigate the role of modified Ross score in the evaluation of children with severe lower respiratory tract infection admitted to the pediatric intensive care unit (PICU). One hundred and sixty-four children with severe LRTI admitted to the PICU were enrolled in this prospective cohort study, which was carried out at Assiut University Children Hospital, from the start of July 2021 up to the end of December 2021. Sixty patients (36.6%) of studied cases with severe LRTI admitted to PICU had HF. Out of these, 37 (61.7%) had mild HF; 17 (28.3%) had moderate HF, while six cases (10%) had severe HF according to the modified Ross score. The value of modified Ross score was significantly higher in children with heart failure with sensitivity and specificity 100% with cutoff value of 2. Admission to NICU, history of previous ventilation, and prematurity were higher in patients who developed HF. Patients with pulmonary hypertension (PH) and those with raised neutrophil lymphocyte ratio were significantly higher in the group of patients with moderate and severe degree of HF.   Conclusion: Modified Ross score is a simple clinical score which may help in assessing and predicting children with severe LRTI. What is Known: • Hear failure is common complication to lower respiratory tract infection. • Modified Ross score was used to predict and classify heart failure in adult with lower respiratory infection. What is New: • Modified Ross score found to be of value in prediction of heart failure in children with lower respiratory tract infection.

Heart rate reduction as a marker to optimize carvedilol treatment and enhance myocardial recovery in pediatric dilated cardiomyopathy

Introduction: An elevated heart rate is associated with an increased risk of death or cardiac transplant in children with dilated cardiomyopathy (DCM). Whether heart rate is a clinical marker to address therapy, is poorly investigated in children. Aim: To investigate the relationship between heart rate reduction (HRR) and left ventricular ejection fraction (LVEF) in DCM, treated with carvedilol. Methods: This is a multi center retrospective analysis conducted on all children with DCM (aged <18 years) between 2013 and 2020, with LVEF <40% and treated with carvedilol. Carvedilol was up titrated to the maximal tolerated dose or to 1 mg/kg/day. Echocardiographic data on left ventricular function and dimension were collected. The relationship between HRR and LVEF, left ventricular end-diastolic (LVEDd) and end-systolic diameter (LVESd) was assessed before and after HRR with carvedilol, using regression analysis. Results: 100 patients were enrolled (M: 51%; age 7 ± 8 years). The mean LVEF was 30.2 ± 10% before treatment and 43.7 ± 9.6% after treatment, at the maximum therapeutic dose (p < 0.0001). There was a positive relationship between HRR and increase in LVEF (R 2 = 0.06, p = 0.014). A HRR of >20% correlated with an improvement in LVEF >13%. At 3 years follow up, HRR demonstrated a significant reduction of LVESd (R2 = 0.1, p = 0.003) LVEDd (R2 = 0.07, p = 0.008) and LVEF recovery up to 15% (p < 0.0001). No deaths or heart transplant occurred during follow-up. Conclusion: This study demonstrates that HRR is safe and improvement in LVEF is related to the degree of HRR. The magnitude of LVEF improvement was enhanced by a major reduction in HR. It provides evidence that HRR could be used as a clinical marker to treat HF in children.

Low serum 25-hydroxyvitamin D (vitamin D) level among children with ventricular septal defect: how big is the risk for pulmonary hypertension?

INTRODUCTION

Ventricular septal defect is the most common CHD, leading to pulmonary hypertension. Significantly lower 25-hydroxyvitamin D level was reported in children with CHD compared with healthy controls. The current study aimed to investigate the correlation between 25-hydroxyvitamin D level and pulmonary hypertension in children with ventricular septal defect.

METHODS

A cross-sectional study was conducted on ventricular septal defect paediatric patients from January to June, 2019. Serum 25-hydroxyvitamin D was measured using electrochemiluminescence. Pulmonary hypertension was defined as mean pulmonary artery systolic pressure > 20 mmHg for children >3 months of age at sea level, measured by Doppler echocardiography.

RESULTS

From forty-four subjects, the majority of the subjects were female (56.8%) with normal nutritional status and perimembranous ventricular septal defect. Bivariate analysis showed that 25-hydroxyvitamin D level was associated with pulmonary hypertension (p < 0.01), type and size of ventricular septal defect (p = 0.02), and heart failure (p < 0.01). Higher 25-hydroxyvitamin D level was correlated with better nutritional status (p = 0.04, r = 0.26), and lower 25-hydroxyvitamin D level was correlated with the occurence of perimembranous ventricular septal defect (p = 0.01, r = -0.39), larger defect size (p < 0.01, r = -0.70), history of pneumonia (p = 0.02, r = -0.31), and heart failure (p < 0.01, r = -0.64). Subjects with 25-hydroxyvitamin D deficiency had prevalence ratio of 24.0 times for pulmonary hypertension. Higher pulmonary artery pressure was correlated to the occurence perimembranous ventricular septal defect (p = 0.01, r = 0.47), larger defect size (p < 0.01, r = 0.78), history of pneumonia (p = 0.01, r = 0.38), and heart failure (p < 0.01, r = 0.75).

CONCLUSION

Children with ventricular septal defect who had low 25-hydroxyvitamin D level posed a higher risk of having pulmonary hypertension.

Predictive Value of Plasma Copeptin Level in Children with Acute Heart Failure

We investigated the ability of copeptin level to predict adverse outcome in pediatric heart failure (HF) and correlated copeptin level with various clinical and echocardiographic data. This cohort study was carried out on forty children with clinical picture of acute HF as the patient group and forty healthy children of matched age and sex as the control group. Echocardiographic examination and plasma copeptin level were performed for all included children at admission. Patients were followed up for 6 months for mortality or readmission. Plasma copeptin level was significantly higher in the patient group (16.2 ± 5) pmol/L compared to the control group (4.1 ± 2.3) pmol/L, P ˂0.001. Moreover, copeptin level was positively correlated with Ross classification, being the highest in patients with class IV (19.6 ± 3.9) pmol/L compared to those with class III (15.2 ± 4) pmol/L and class II (10.4 ± 1.5) pmol/L. Copeptin levels were significantly higher in patients with bad prognosis (21.2 ± 4.1) pmol/L compared to those with good prognosis (14.5 ± 4.1) pmol/L, P ˂0.001. Copeptin level had a significant positive correlation with age, heart rate, respiratory rate, and ROSS classification. On the contrary, copeptin level had a significant negative correlation with left ventricular fraction shortening and diastolic function. Copeptin at cut-off value of ≥ 19.5 pmol/L yielded a sensitivity of 75% and a specificity of 93% to predict adverse outcome in children with HF. Plasma copeptin level has a good prognostic value to predict adverse outcome in pediatric heart failure. Moreover, copeptin correlate well with the severity of pediatric HF.

The use of N-terminal (1-76) pro-brain natriuretic peptide in the aetiology of severe respiratory distress in the paediatric emergency department

INTRODUCTION

Acute respiratory distress is one of the most common reasons for paediatric emergency visits. Paediatric patients require rapid diagnosis and treatment. Our aim in this study was to use N-terminal (1-76) pro-brain natriuretic peptide to differentiate respiratory distress of cardiac and pulmonary origin in children. Our aim was to investigate the role of N-terminal (1-76) pro-brain natriuretic peptide in the detection of patients with new-onset heart failure in the absence of an underlying congenital heart anomaly.

METHODS

All children aged 0-18 years who presented to the paediatric emergency department due to severe respiratory distress were included in the study prospectively. The patients' demographic characteristics, presenting complaints, clinical findings, and N-terminal (1-76) pro-brain natriuretic peptide concentrations, were investigated. In patients with severe Pediatric Respiratory Severity Score, congestive heart failure score was calculated using the modified Ross Score.

RESULTS

This study included 47 children between the ages of 1 month and 14 years. The median N-terminal (1-76) pro-brain natriuretic peptide concentration was 5717 (IQR:16158) pg/mL in the 25 patients with severe respiratory distress due to heart failure and in the 22 patients with severe respiratory distress due to lung pathology was 437 (IQR:874) pg/mL (p < 0.001). In the 25 patients with severe respiratory distress due to heart failure, 8281 (IQR:8372) pg/mL in the 16 patients with underlying congenital heart anomalies, and 1983 (IQR:2150) pg/mL in the 9 patients without a congenital heart anomaly (p < 0.001). The 45 patients in the control group had a median N-terminal (1-76) pro-brain natriuretic peptide concentration of 47.2 (IQR:56.2) pg/mL.

CONCLUSION

Using scoring systems in combination with N-terminal (1-76) pro-brain natriuretic peptide cut-off values can help direct and manage treatment.

Age-adjusted NT-proBNP could help in the early identification and follow-up of children at risk for severe multisystem inflammatory syndrome associated with COVID-19 (MIS-C)

BACKGROUND

Multisystem inflammatory syndrome in children (MIS-C) has emerged as a new disease associated with COVID-19 that presents in acute critically ill children with acute cardiovascular dysfunction.

AIM

To determine whether the age-adjusted N-terminal pro-brain natriuretic peptide (NT-proBNP) value (Z-log-NT-proBNP) is associated with severe MIS-C and myocardial dysfunction.

METHODS

A retrospective study was conducted which included children with MIS-C managed at our institution between April 1, 2020, and February 28, 2022. We divided the population into groups depending on severity based on pediatric intensive care unit (PICU) admission. We compared Z-log-NT-proBNP values across these groups and analyzed Z-log-NT-proBNP dynamics during the one-month follow-up.

RESULTS

We included 17 participants [median age 3 (2-9) years] and seven (41%) required PICU admission. All (100%) of these cases presented very high (Z-log > 4) levels of NT-proBNP at the time of admission compared to only 5 (50%) patients with non-severe MIS-C (P = 0.025). NT-proBNP was significantly correlated with high-sensitive Troponin I levels (P = 0.045), Ross modified score (P = 0.003) and left ventricle ejection fraction (P = 0.021).

CONCLUSION

Raised NT-proBNP, specifically very high values (Z-log-NT-proBNP > 4) could help in the early identification of MIS-C patients with myocardial dysfunction requiring inotropic support and PICU admission.

Serum Biomarkers for the Detection of Cardiac Dysfunction in Childhood Cancers Receiving Anthracycline-Based Treatment

Anthracyclines are routinely used in cancer chemotherapy in many childhood cancers. A serious adverse effect of doxorubicin chemotherapy is cardiotoxicity which may lead to congestive heart failure for long-term survivors years after treatment. Currently, echocardiography is used to control the heart function during anthracyclines therapy. B-type natriuretic peptide (BNP) and NT-proBNP as well as cardiac troponins have been proposed as clinical markers for subclinical anthracycline-induced cardiotoxicity. The BNP and pro-BNP can be easily measured in plasma and initial data indicate that the NT-proBNP could be sensitive predictor for the development of congestive heart failure.

Poor efficacy of oral iron replacement therapy in pediatric patients with heart failure

INTRODUCTION

Iron deficiency is associated with worse outcomes in children and adults with systolic heart failure. While oral iron replacement has been shown to be ineffective in adults with heart failure, its efficacy in children with heart failure is unknown. We hypothesised that oral iron would be ineffective in replenishing iron stores in ≥50% of children with heart failure.

METHODS

We performed a single-centre retrospective cohort study of patients aged ≤21 years with systolic heart failure and iron deficiency who received oral iron between 01/2013 and 04/2019. Iron deficiency was defined as ≥2 of the following: serum iron <50 mcg/dL, serum ferritin <20 ng/mL, transferrin >300 ng/mL, transferrin saturation <15%. Iron studies and haematologic indices pre- and post-iron therapy were compared using paired-samples Wilcoxon test.

RESULTS

Fifty-one children with systolic heart failure and iron deficiency (median age 11 years, 49% female) met inclusion criteria. Heart failure aetiologies included cardiomyopathy (51%), congenital heart disease (37%), and history of heart transplantation with graft dysfunction (12%). Median dose of oral iron therapy was 2.9 mg/kg/day of elemental iron, prescribed for a median duration of 96 days. Follow-up iron testing was available for 20 patients, of whom 55% (11/20) remained iron deficient despite oral iron therapy.

CONCLUSIONS

This is the first report on the efficacy of oral iron therapy in children with heart failure. Over half of the children with heart failure did not respond to oral iron and remained iron deficient.

Clinical Characteristics of Hospitalized Pediatric Patients With Hypertensive Crisis—A Retrospective, Single-Center Study in China

Background

A hypertensive crisis is a medical emergency that causes acute damage to multiple organs. However, the etiology, clinical features, and prognosis of hypertensive crisis in Chinese children remain relatively unknown. The purpose of this study was to analyze the clinical characteristics of pediatric hypertensive crisis patients from a single center in China.

Methods

We analyzed data from 70 children with hypertensive crisis between January, 2000, and January, 2022. The patients were divided into two groups: those diagnosed with a hypertensive emergency (n = 46) and those diagnosed with hypertensive urgency (n = 24). Baseline etiologies and risk factors were compared between the two groups. The following data were collected and analyzed: age, sex, weight, height, family history of hypertension, blood pressure, clinical manifestations of hypertensive crisis, underlying causes, biochemical indicators, and antihypertensive drugs.

Results

The major symptoms of hypertensive crisis were headache (n = 31, 44.29%), followed by visual symptoms (n = 15, 21.43%), and dizziness (n = 13, 18.57%). Further analysis showed that the incidence of convulsions was significantly higher in patients with hypertensive emergency than those with hypertensive urgency (χ2 = 5.38, p = 0.02). The leading underlying causes were renal disease (n = 34, 48.57%), followed by vascular disease (n = 11, 15.71%), essential hypertension (n = 9, 12.86%), oncological disease (n = 9, 12.86%), central nervous system disease (n = 3, 4.29%), endocrine and metabolic diseases (n = 2, 2.86%), and other (one case with lead poisoning, one case with histiocytosis). End-organ damage occurred in 46 patients with hypertensive crisis, including retinal damage (n = 20, 43.48%), brain damage (n = 19, 41.30%), heart damage (n = 15, 32.61%), and renal damage (n = 3, 6.52%). Hypertensive crisis was most common among children aged 7–12 years. Among children aged 13–18 years, hypertensive urgency was more common than hypertensive emergency. The incidence of dyslipidemia, elevated serum creatinine, and elevated uric acid did not differ significantly between the two groups. Most patients with hypertensive crisis need combined antihypertensive therapy (n = 60, 85.71%). There were no cases of mortality.

Conclusions

Hypertensive crisis is caused by secondary diseases, especially renal disease and vascular disease, in the majority of pediatric patients. Combination therapy with antihypertensive agents and treatment of secondary etiology results in a good prognosis.

Risk factors for insufficient weight and height gain in children with congenital heart disease followed up at a nutrition outpatient clinic

OBJECTIVE

To describe weight and height evolution and to identify risk factors for insufficient anthropometric growth in children with congenital heart disease.

METHODS

Historical cohort study including 131 children with congenital heart disease, followed up at a nutrition outpatient clinic. The anthropometric indices over time (initial score, after 12 and 24 months of follow-up) were analyzed using generalized estimating equations. The outcome was 'insufficient weight-height gain', defined as an increase of ≤0.5 in the z-score of weight-for-age (W/A), height-for-age (H/A) or body mass index-for-age (BMI/A) after 12 months of follow-up. Multiple logistic regression models were applied to identify risk and confounding factors.

RESULTS

The z-scores of W/A (p<0.001) and BMI/A (p<0.001) improved after 12 months, as well as the three indexes after 24 months (p<0.001). At the end of this period, 55.7% of the patients did not achieve an increase of >0.5 in the Z score of W/A; 77.1%, of H/A; and 45.8%, of BMI/A. A follow-up of less than five appointments was associated with insufficient gain in W/A (OR 7.78; 95%CI 3.04-19.88), H/A (OR 10.79; 95%CI 2.22-52.45) and BMI/A (OR 2.54; 95%CI 1.12-5.75). Not having undergone cardiac surgery and being aged ≥12 months were factors associated with insufficient W/A gain (OR 3.95; 95%CI 1.38-11.29/OR 3.60; 95%CI 1.33-9.72) and BMI/A (OR 2.81; 95%CI 1.08-7.28/OR 3.39; 95%CI 1.34-8.56). Low income was associated with insufficient H/A gain (OR 4.11; 95%CI 1.25-13.46).

CONCLUSIONS

Being aged less than or 12 months, the lowest number of appointments, absence of surgical treatment and low family income were risk factors for insufficient weight and height gain in children with congenital heart disease.

Clinical Features and Natural History of Preadolescent Nonsyndromic Hypertrophic Cardiomyopathy

BACKGROUND

Up to one-half of childhood sarcomeric hypertrophic cardiomyopathy (HCM) presents before the age of 12 years, but this patient group has not been systematically characterized.

OBJECTIVES

The aim of this study was to describe the clinical presentation and natural history of patients presenting with nonsyndromic HCM before the age of 12 years.

METHODS

Data from the International Paediatric Hypertrophic Cardiomyopathy Consortium on 639 children diagnosed with HCM younger than 12 years were collected and compared with those from 568 children diagnosed between 12 and 16 years.

RESULTS

At baseline, 339 patients (53.6%) had family histories of HCM, 132 (20.9%) had heart failure symptoms, and 250 (39.2%) were prescribed cardiac medications. The median maximal left ventricular wall thickness z-score was 8.7 (IQR: 5.3-14.4), and 145 patients (27.2%) had left ventricular outflow tract obstruction. Over a median follow-up period of 5.6 years (IQR: 2.3-10.0 years), 42 patients (6.6%) died, 21 (3.3%) underwent cardiac transplantation, and 69 (10.8%) had life-threatening arrhythmic events. Compared with those presenting after 12 years, a higher proportion of younger patients underwent myectomy (10.5% vs 7.2%; P = 0.045), but fewer received primary prevention implantable cardioverter-defibrillators (18.9% vs 30.1%; P = 0.041). The incidence of mortality or life-threatening arrhythmic events did not differ, but events occurred at a younger age.

CONCLUSIONS

Early-onset childhood HCM is associated with a comparable symptom burden and cardiac phenotype as in patients presenting later in childhood. Long-term outcomes including mortality did not differ by age of presentation, but patients presenting at younger than 12 years experienced adverse events at younger ages.

Relationship Between Maximal Left Ventricular Wall Thickness and Sudden Cardiac Death in Childhood Onset Hypertrophic Cardiomyopathy

BACKGROUND

Maximal left ventricular wall thickness (MLVWT) is a risk factor for sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM). In adults, the severity of left ventricular hypertrophy has a nonlinear relationship with SCD, but it is not known whether the same complex relationship is seen in childhood. The aim of this study was to describe the relationship between left ventricular hypertrophy and SCD risk in a large international pediatric HCM cohort.

METHODS

The study cohort comprised 1075 children (mean age, 10.2 years [±4.4]) diagnosed with HCM (1-16 years) from the International Paediatric Hypertrophic Cardiomyopathy Consortium. Anonymized, noninvasive clinical data were collected from baseline evaluation and follow-up, and 5-year estimated SCD risk was calculated (HCM Risk-Kids).

RESULTS

MLVWT Z score was <10 in 598 (58.1%), ≥10 to <20 in 334 (31.1%), and ≥20 in 143 (13.3%). Higher MLVWT Z scores were associated with heart failure symptoms, unexplained syncope, left ventricular outflow tract obstruction, left atrial dilatation, and nonsustained ventricular tachycardia. One hundred twenty-two patients (71.3%) with MLVWT Z score ≥20 had coexisting risk factors for SCD. Over a median follow-up of 4.9 years (interquartile range, 2.3-9.3), 115 (10.7%) had an SCD event. Freedom from SCD event at 5 years for those with MLVWT Z scores <10, ≥10 to <20, and ≥20 was 95.6%, 87.4%, and 86.0, respectively. The estimated SCD risk at 5 years had a nonlinear, inverted U-shaped relationship with MLVWT Z score, peaking at Z score +23. The presence of coexisting risk factors had a summative effect on risk.

CONCLUSIONS

In children with HCM, an inverted U-shaped relationship exists between left ventricular hypertrophy and estimated SCD risk. The presence of additional risk factors has a summative effect on risk. While MLVWT is important for risk stratification, it should not be used either as a binary variable or in isolation to guide implantable cardioverter defibrillator implantation decisions in children with HCM.

MYH7 Genotype–Phenotype Correlation in a Cohort of Finnish Patients

Cardiomyopathies (CMPs) are a heterogeneous group of diseases, frequently genetic, affecting the heart muscle. The symptoms range from asymptomatic to dyspnea, arrhythmias, syncope, and sudden cardiac death. This study is focused on MYH7 (beta-myosin heavy chain), as this gene is commonly mutated in cardiomyopathy patients. Due to the high combined prevalence of MYH7 variants and severe health outcomes, it is one of the most frequently tested genes in clinical settings. We analyzed the clinical presentation and natural history of 48 patients with MYH7-related cardiomyopathy belonging to a cohort from a tertiary center at Helsinki University Hospital, Finland. We made special reference to three age subgroups (0–1, 1–12, and >12 years). Our results characterize a clinically significant MYH7 cohort, emphasizing the high variability of the CMP phenotype depending on age. We observed a subgroup of infants (0–1 years) with MYH7 associated severe DCM phenotype. We further demonstrate that patients under the age of 12 years have a similar symptom burden compared to older patients.

The Association between NTproBNP Biomarker Levels and Clinical Symptoms of Cardiac Septal Defects in Children

BACKGROUND: In a cardiac septal defect, there is left-to-right shunt at the atrial, ventricle level, or both. This causes clinical symptoms of heart failure, pulmonary hypertension, or malnutrition. NTproBNP is synthesized and released into the circulation by the ventricular myocytes in response to pressure, volume overload, and increase in myocardial wall stress. AIM: This study aims to evaluate relationship between NTproBNP levels and clinical symptoms of cardiac septal defect. PATIENTS AND METHODS: This cross-sectional study was conducted from April to August 2021 at Moh Husin Hospital, Palembang, Indonesia. The presence of heart failure was determined using the modified Ross score. Nutritional status was defined on anthropometric measurement, and data were plot to weight to height Z-score chart. The presence of pulmonary hypertension was measured by Doppler echocardiography. RESULTS: A total of 75 cardiac septal defect patients were included in this study. A similar plasma NTproBNP of 554 pg/ml was determined as the cut-off point for predicting heart failure and pulmonary hypertension, with a sensitivity of 57.1% and 54.5%, specificity of 85% and 80.9%, with area under receiver operating characteristic (ROC) of 0.706 and 0.716 respectively. For malnutrition, plasma NTproBNP of 429 pg/ml was found to have sensitivity, specificity, and area under ROC of 54.3%, 77.5%, and 0.640, respectively. The multivariate logistic regression showed that NTproBNP >554 pg/ml and >429 pg/ml had a 6-fold higher odds of having heart failure, an 8-fold higher odds of having pulmonary hypertension, and a 4-fold odds of having malnutrition. CONCLUSION: NTproBNP is a biomarker that is strong enough to predict clinical symptoms of heart failure, pulmonary hypertension, and malnutrition in children with cardiac septal defect.

Fatores de risco para evolução pôndero-estatural insuficiente de crianças com cardiopatia congênita acompanhadas em ambulatório de nutrição clínica

Resumo Objetivo: Descrever a evolução pôndero-estatural e identificar fatores de risco para o crescimento antropométrico insuficiente de crianças com cardiopatia congênita. Métodos: Coorte histórica de 131 crianças com cardiopatia congênita acompanhadas em ambulatório de nutrição clínica. Os escores dos índices antropométricos ao longo do tempo (inicial, após 12 e 24 meses de acompanhamento) foram analisados por equações de estimativas generalizadas. O desfecho foi o ganho pôndero-estatural insuficiente, definido como aumento ≤0,5 nos escores Z de peso para idade (P/I), estatura para idade (E/I) e índice de massa corpórea para idade (IMC/I) em 12 meses de acompanhamento. Foram aplicados modelos de regressão logística múltipla para identificação dos fatores de risco e controle dos fatores de confusão. Resultados: Os escores Z de P/I (p<0,001) e IMC/I (p<0,001) melhoraram após 12 meses, e os três índices após 24 meses (p<0,001). Ao final desse período, 55,7% dos pacientes não alcançaram aumento >0,5 escore Z de P/I; 77,1%, de E/I; e 45,8%, de IMC/I. O acompanhamento inferior a cinco consultas associou-se ao ganho insuficiente de P/I (OR 7,78, IC95% 3,04–19,88), E/I (OR 10,79, IC95% 2,22–52,45) e IMC/I (OR 2,54, IC95% 1,12–5,75). Não ter sido submetido à cirurgia cardíaca e ter idade ≥12 meses estiveram associados ao ganho insuficiente de P/I (OR 3,95, IC95% 1,38–11,29/ OR 3,60, IC95% 1,33–9,72) e IMC/I (OR 2,81, IC95% 1,08–7,28/OR 3,39, IC95% 1,34–8,56), e a baixa renda, ao ganho insuficiente de E/I (OR 4,11, IC95% 1,25–13,46). Conclusões: Idade ≥12 meses, menor número de consultas, ausência de tratamento cirúrgico e baixa renda familiar foram fatores de risco para a evolução pôndero-estatural insuficiente em crianças com cardiopatia congênita.

Utility of perinatal natriuretic peptide for predicting neonatal heart failure

BACKGROUND

We evaluated the significance of perinatal plasma natriuretic peptide (NP) levels in neonates with congenital heart defects (CHDs) or arrhythmias and determined whether measurement of perinatal plasma NP levels and echocardiographic assessment in utero could predict heart failure after birth.

METHODS

The study was conducted between 2012 and 2016 to evaluate the correlation of perinatal atrial NP (ANP) and brain NP (BNP) levels at birth with the modified Ross score after birth and the cardiovascular profile (CVP) score before birth.

RESULTS

A total of 122 singletons with CHDs or arrhythmias and 27 controls were analyzed. Neonatal blood sampling was performed at a median of 0.7 h (range, 0.1-1.5) after birth. The neonatal plasma ANP and BNP levels shortly after birth were significantly higher than those in the umbilical artery (UA) plasma. The ANP and BNP levels in UA and neonatal blood were correlated with the modified Ross score. The neonatal plasma ANP and BNP levels and the modified Ross scores were inversely correlated with the CVP score in neonates with CHDs or arrhythmias. The area under the receiver operating characteristic curve of UA ANP levels for predicting neonatal heart failure was highest among those for the CVP score, perinatal plasma ANP and BNP levels, and their combinations.

CONCLUSIONS

The plasma ANP and BNP levels increased markedly shortly after birth. Assessment of the UA plasma ANP level at birth and the CVP score in utero may be utilized to predict neonatal heart failure.

Anatomic Repair of Congenitally Corrected Transposition: Reappraisal of Eligibility Criteria

Several criteria to identify suitable candidates for anatomic repair in congenitally corrected transposition (cc-TGA) have been proposed. The purpose of this study was to critically re-evaluate adequacy of these recommendations in our patient cohort. All cc-TGA patients undergoing anatomic repair between 2010 and 2019 were reviewed. Evaluated eligibility criteria for repair included age ≤ 15 years, LV mass index ≥ 45-50 g/m², LV mass/volume ratio > 0.9-1.5 and systolic LV to right ventricle pressure ratio > 70-90% among others. Repair failure was defined as postoperative early mortality or LV dysfunction requiring mechanical circulatory support. Twenty-five patients were included (median [interquartile range] age at surgery 1.8 years [0.7;6.6]; median postoperative follow-up 3.2 years [0.7;6.3]). Median preoperative LV ejection fraction was 60% [56;64], indexed LV mass 48.5 g/m² [43.7;58.1] and LV mass/volume ratio 1.5 [1.1;1.6], respectively. A total of 12 patients (48%) did not meet at least one of the previously recommended criteria, however, all but two patients (92%) experienced favorable early outcome. Of 7 patients (28%) with indexed LV mass < 45 g/m², 6 were successfully operated. There were two early repair failures (8%) with LV dysfunction: one patient died and one required mechanical circulatory support but recovered well. Surgery was performed successfully in patients with LV mass and volume Z-scores as low as - 2 and - 2.5, respectively. Anatomic correction for cc-TGA can be performed with excellent early outcome and is feasible even in patients with LV mass below previously recommended cut-offs. The use of LV mass and volume Z-scores might help to refine eligibility criteria.

Pericardial Constriction and Myocardial Restriction in Pediatric Mulibrey Nanism: A Complex Disease With Diastolic Dysfunction

Background

Mulibrey nanism (MUL) is a rare condition with profound growth delay. Congestive heart failure is a major determinant of prognosis. The aim was to delineate pericardial constriction and myocardial functional abnormalities in a pediatric MUL sample.

Methods

A total of 23 MUL patients and 23 individually sex- and age-matched healthy control subjects were prospectively assessed in a cross-sectional study with echocardiography.

Results

Clinical signs of heart failure were present in 7 MUL patients, with severe congestive heart failure in 2. Significant diastolic dysfunction, mainly related to constriction, was found in MUL patients without pericardiectomy (N = 18)—septal bounce, pronounced hepatic vein atrial reversal and right heart inflow–outflow variations, and decreased inferior vena cava collapse during respiration. The appearance of the pericardium was not different from that of control subjects. Longitudinal diastolic myocardial velocities were similar to those in control subjects, suggesting an absence of significant myocardial restriction. Right ventricular free wall longitudinal systolic strain and bilateral longitudinal myocardial systolic velocities were decreased in MUL patients, indicating mild biventricular systolic dysfunction. Myocardial motion abnormalities and persistent congestive heart failure were common (in 3 of 6) in MUL patients with a history of pericardiectomy. Cardiac dimensions were similar between MUL patients and control subjects when adjusting for body size, except for smaller biventricular volumes.

Conclusions

MUL disease presents with significant constriction-related diastolic dysfunction and mild bilateral systolic dysfunction. Constriction–restriction assessments during follow-up could be of benefit in decision-making regarding pericardiectomy in MUL disease. Myocardial abnormalities were prevalent among MUL patients who had undergone pericardiectomy and are consistent with progression of myocardial disease in a significant proportion of patients.

Pediatric Diastolic Heart Failure: Clinical Features Description of 421 Cases

BACKGROUND AND AIM

Heart failure in children differs substantially from the adult population. Clinical characteristics of pediatric diastolic heart failure has rarely been reported. In this study, we aimed to summary the causes, clinical features, lab tests, and treatment effect of pediatric diastolic heart failure.

METHODS

This study was a single center, retrospective study conducted in Children's Hospital of Chongqing Medical University. Children who were diagnosed with diastolic heart failure (DHF) without systolic heart failure (SHF) between 2006 and 2014 were included. Meanwhile, SHF (without DHF) cases were also collected from 2013 to 2014.

RESULTS

A total of 421 DHF and 42 SHF cases were included. The average age of pediatric DHF was 1.89 ± 3.29 years old, significant younger than that of SHF (4.65 ± 4.90). The top three cardiovascular causes of DHF were complex congenital heart malformations (53.4%), simple congenital heart defect (15.7%), and cardiomyopathy (7.4%). Alternatively, number of cardiomyopathy cases (57.1%) ranked first in SHF group. Simple congenital heart diseases (CHDs) rarely caused SHF. The most common symptom and sign were tachypnea and hepatomegaly in pediatric HF. Symptoms like cyanosis, feeding difficulty, be fidgety, pale, fatigue, and edema were valuable in differential diagnosis of DHF and SHF in children. B-type natriuretic peptide (BNP) increase was found in 36.9% of DHF children, and 60% in SHF patients. Sensitivity of BNP greater than 100 pg/ml in diagnosis of DHF was 0.37, and specificity of it was 0.86. Diastolic function indicators, such as E/A (early wave/late wave) ratio, IVRT (isovolumic relaxation time) were significant recovered after treatment in DHF patients. Less therapeutic benefits were achieved in children with cardiomyopathy induced DHF, in compared with non-cardiomyopathy patients.

CONCLUSION

Pediatric DHF and SHF were largely different in primary causes, clinical symptoms and signs and short-term prognosis. There was a limit diagnostic value of BNP with 100 pg/ml as cut-off value in pediatric DHF. Larger, multicenter studies of pediatric DHF are required in the future.

Not Only Diagnostic Yield: Whole-Exome Sequencing in Infantile Cardiomyopathies Impacts on Clinical and Family Management

Whole-exome sequencing (WES) is a powerful and comprehensive tool for the genetic diagnosis of rare diseases, but few reports describe its timely application and clinical impact on infantile cardiomyopathies (CM). We conducted a retrospective analysis of patients with infantile CMs who had trio (proband and parents)-WES to determine whether results contributed to clinical management in urgent and non-urgent settings. Twenty-nine out of 42 enrolled patients (69.0%) received a definitive molecular diagnosis. The mean time-to-diagnosis was 9.7 days in urgent settings, and 17 out of 24 patients (70.8%) obtained an etiological classification. In non-urgent settings, the mean time-to-diagnosis was 225 days, and 12 out of 18 patients (66.7%) had a molecular diagnosis. In 37 out of 42 patients (88.1%), the genetic findings contributed to clinical management, including heart transplantation, palliative care, or medical treatment, independent of the patient’s critical condition. All 29 patients and families with a definitive diagnosis received specific counseling about recurrence risk, and in seven (24.1%) cases, the result facilitated diagnosis in parents or siblings. In conclusion, genetic diagnosis significantly contributes to patients’ clinical and family management, and trio-WES should be performed promptly to be an essential part of care in infantile cardiomyopathy, maximizing its clinical utility.

Clinical presentation and long-term outcomes of infantile hypertrophic cardiomyopathy: a European multicentre study

AIMS

Children presenting with hypertrophic cardiomyopathy (HCM) in infancy are reported to have a poor prognosis, but this heterogeneous group has not been systematically characterized. This study aimed to describe the aetiology, phenotype, and outcomes of infantile HCM in a well-characterized multicentre European cohort.

METHODS AND RESULTS

Of 301 children diagnosed with infantile HCM between 1987 and 2019 presenting to 17 European centres [male n = 187 (62.1%)], underlying aetiology was non-syndromic (n = 138, 45.6%), RASopathy (n = 101, 33.6%), or inborn error of metabolism (IEM) (n = 49, 16.3%). The most common reasons for presentation were symptoms (n = 77, 29.3%), which were more prevalent in those with syndromic disease (n = 62, 61.4%, P < 0.001), and an isolated murmur (n = 75, 28.5%). One hundred and sixty-one (53.5%) had one or more co-morbidities. Genetic testing was performed in 163 (54.2%) patients, with a disease-causing variant identified in 115 (70.6%). Over median follow-up of 4.1 years, 50 (16.6%) underwent one or more surgical interventions; 15 (5.0%) had an arrhythmic event (6 in the first year of life); and 48 (15.9%) died, with an overall 5 year survival of 85%. Predictors of all-cause mortality were an underlying diagnosis of IEM [hazard ratio (HR) 4.4, P = 0.070], cardiac symptoms (HR 3.2, P = 0.005), and impaired left ventricular systolic function (HR 3.0, P = 0.028).

CONCLUSIONS

This large, multicentre study of infantile HCM describes a complex cohort of patients with a diverse phenotypic spectrum and clinical course. Although overall outcomes were poor, this was largely related to underlying aetiology emphasizing the importance of comprehensive aetiological investigations, including genetic testing, in infantile HCM.