Left Ventricular Function in Children and Adolescents With Arrhythmogenic Right Ventricular Cardiomyopathy

Multimodality imaging in arrhythmogenic cardiomyopathy - From diagnosis to management

Arrhythmogenic Cardiomyopathy (AC), an inherited cardiac disorder characterized by myocardial fibrofatty replacement, carries a significant risk of sudden cardiac death (SCD) due to ventricular arrhythmias. A comprehensive multimodality imaging approach, including echocardiography, cardiac magnetic resonance imaging (CMR), and cardiac computed tomography (CCT), allows for accurate diagnosis, effective risk stratification, vigilant monitoring, and appropriate intervention, leading to improved patient outcomes and the prevention of SCD. Echocardiography is primary tool ventricular morphology and function assessment, CMR provides detailed visualization, CCT is essential in early stages for excluding congenital anomalies and coronary artery disease. Echocardiography is preferred for follow-up, with CMR capturing changes over time. The strategic use of these imaging methods aids in confirming AC, differentiating it from other conditions, tracking its progression, managing complications, and addressing end-stage scenarios.

Arrhythmogenic Right Ventricular Cardiomyopathy in Children: A Systematic Review

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited disease characterized by the progressive replacement of the normal myocardium by fibroadipocytic tissue. The importance of an early diagnosis is supported by a higher risk of sudden cardiac death in the pediatric population. We reviewed the literature on diagnosis, risk stratification, and prognosis in the pediatric population with ARVC. In case reports which analyzed children with ARVC, the most common sign was ventricular tachycardia, frequently presenting as dizziness, syncope, or even cardiac arrest. Currently, there is no gold standard for diagnosing ARVC in children. Nevertheless, genetic analysis may provide a proper diagnosis tool for asymptomatic cases. Although risk stratification is recommended in patients with ARVC, a validated prediction model for risk stratification in children is still lacking; thus, it is a matter of further research. In consequence, even though ARVC is a relatively rare condition in children, it negatively impacts the survival and clinical outcomes of the patients. Therefore, appropriate and validated diagnostic and risk stratification tools are crucial for the early detection of children with ARVC, ensuring a prompt therapeutic intervention.

The Many Faces of Arrhythmogenic Cardiomyopathy: An Overview

Arrhythmogenic cardiomyopathy (AC) is a disease that involves electromechanical uncoupling of cardiomyocytes. This leads to characteristic histologic changes that ultimately lead to the arrhythmogenic clinical features of the disease. Initially thought to affect the right ventricle predominantly, more recent data show that it can affect both the ventricles or the left ventricle alone. Throughout the recent era, diagnostic modalities and criteria for AC have continued to evolve and our understanding of its clinical features in different age groups as well as the genotype to the phenotype correlations have improved. In this review, we set out to detail the epidemiology, etiologies, presentations, evaluation, and management of AC across the age continuum.

The phenotypic and genetic features of arrhythmogenic cardiomyopathy in the pediatric population

Introduction

The present study aimed to describe the phenotypic features and genetic spectrum of arrhythmogenic cardiomyopathy (ACM) presented in childhood and test the validity of different diagnostic approaches using Task Force Criteria 2010 (TFC) and recently proposed Padua criteria.

Patients and methods

Thirteen patients (mean age at diagnosis 13.6 ± 3.7 years) were enrolled using "definite" or "borderline" diagnostic criteria of ACM according to the TFC 2010 and the Padua criteria in patients <18 years old. Clinical data, including family history, 12-lead electrocardiogram (ECG), signal-averaged ECG, 24-h Holter monitoring, imaging techniques, genetic testing, and other relevant information, were collected.

Results

All patients were classified into three variants: ACM of right ventricle (ACM-RV; n = 6, 46.1%), biventricular ACM (ACM-BV; n = 3, 23.1%), and ACM of left ventricle (ACM-LV; n = 4, 30.8%). The most common symptoms at presentations were syncope (n = 6; 46.1%) and palpitations (n = 5; 38.5%). All patients had more than 500 premature ventricular contractions per day. Ventricular tachycardia was reported in 10 patients (76.9%), and right ventricular dilatation was registered in 8 patients (61.5%). An implantable cardiac defibrillator was implanted in 61.5% of cases, and three patients with biventricular involvement underwent heart transplantation. Desmosomal mutations were identified in 8 children (53.8%), including four patients with PKP2 variants, two with DSP variants, one with DSG2 variant, and one with JUP. Four patients carried compound heterozygous variants in desmosomal genes associated with left ventricular involvement.

Conclusion

Arrhythmias and structural heart disease, such as chamber dilatation, should raise suspicion of different ACM phenotypes. Diagnosis of ACM might be difficult in pediatric patients, especially for ACM-LV and ACM-BV forms. Our study confirmed that using "Padua criteria" in combination with genetic testing improves the diagnostic accuracy of ACM in children.

Cardiomyopathies in children: An overview

Paediatric cardiomyopathies form a heterogeneous group of disorders characterized by structural and electrical abnormalities of the heart muscle, commonly due to a gene variant of the myocardial cell structure. Mostly inherited as a dominant or occasionally recessive trait, they might be part of a syndromic disorder of underlying metabolic or neuromuscular defects or combine early developing extracardiac abnormalities (i.e., Naxos disease). The annual incidence of 1 per 100,000 children appears higher during the first two years of life. Dilated and hypertrophic cardiomyopathy phenotypes share an incidence of 60% and 25%, respectively. Arrhythmogenic right ventricular cardiomyopathy (ARVC), restrictive cardiomyopathy, and left ventricular noncompaction are less commonly diagnosed. Adverse events such as severe heart failure, heart transplantation, or death usually appear early after the initial presentation. In ARVC patients, high-intensity aerobic exercise has been associated with worse clinical outcomes and increased penetrance in at-risk genotype-positive relatives. Acute myocarditis in children has an incidence of 1.4-2.1 cases/per 100,000 children per year, with a 6-14% mortality rate during the acute phase. A genetic defect is considered responsible for the progression to dilated cardiomyopathy phenotype. Similarly, a dilated or arrhythmogenic cardiomyopathy phenotype might emerge with an episode of acute myocarditis in childhood or adolescence. This review provides an overview of childhood cardiomyopathies focusing on clinical presentation, outcome, and pathology.

Arrhythmogenic cardiomyopathy is under-recognized in end-stage pediatric heart failure: A 36-year single-center experience

BACKGROUND

Although ventricular failure is a late finding in adults with AC, we hypothesize that this is a presenting symptom in pediatric heart failure patients who undergo HT and that their ventricular arrhythmia burden could differentiate AC from other cardiomyopathies.

METHODS

We performed a single-center retrospective cohort study reviewing 457 consecutive pediatric (≤18 years) HT recipients at our institution. Explanted hearts were examined to establish the primary diagnosis, based on pathologic findings. Demographic and clinical variables were compared between AC versus non-HCM cardiomyopathy cases.

RESULTS

Forty-five percent (n = 205/457) had non-HCM cardiomyopathies as the underlying primary diagnosis. Ten cases (10/205 = 4.9%) were diagnosed with AC. All 10 had biventricular disease. In 8/10 patients (80%), AC diagnosis was unrecognized pre-HT. Compared with non-AC cardiomyopathies, the AC group was older at diagnosis (9.3 years vs. 4.3 years, p = .012) and transplant (11.1 years vs. 6.5 years, p = .010), had more ventricular arrhythmias (80.0% vs 32.8%, p = .003), and required more anti-arrhythmic use (80.0% vs 32.3%, p = .001). Genetic testing yielded causative pathogenic variants in all tested individuals (n = 5/5, 100%).

CONCLUSION

AC is often an unrecognized cardiomyopathy pretransplant in children who undergo HT. Pediatric non-HCM phenotypes with heart failure who have a significant ventricular arrhythmia burden should be investigated for AC.

SCMR expert consensus statement for cardiovascular magnetic resonance of acquired and non-structural pediatric heart disease

Cardiovascular magnetic resonance (CMR) is widely used for diagnostic imaging in the pediatric population. In addition to structural congenital heart disease (CHD), for which published guidelines are available, CMR is also performed for non-structural pediatric heart disease, for which guidelines are not available. This article provides guidelines for the performance and reporting of CMR in the pediatric population for non-structural ("non-congenital") heart disease, including cardiomyopathies, myocarditis, Kawasaki disease and systemic vasculitides, cardiac tumors, pericardial disease, pulmonary hypertension, heart transplant, and aortopathies. Given important differences in disease pathophysiology and clinical manifestations as well as unique technical challenges related to body size, heart rate, and sedation needs, these guidelines focus on optimization of the CMR examination in infants and children compared to adults. Disease states are discussed, including the goals of CMR examination, disease-specific protocols, and limitations and pitfalls, as well as newer techniques that remain under development.

Arrhythmogenic Cardiomyopathy: Diagnosis, Evolution, Risk Stratification and Pediatric Population—Where Are We?

Arrhythmogenic cardiomyopathy (ACM) is a cardiomyopathy characterized by the occurrence of a high risk of life-threatening ventricular arrhythmias and sudden cardiac death even at presentation. Diagnosis, evolution and outcomes in adults have been extensively reported, but little data in pediatric population are available. Risk stratification in this particular setting is still a matter of debate and new risk factors are needed in a model of an ever more “individualized medicine”.

Clinical Characteristics and Follow-Up of Pediatric-Onset Arrhythmogenic Right Ventricular Cardiomyopathy

OBJECTIVES

The goal of this study was to describe characteristics, cascade screening results, and predictors of adverse outcome in pediatric-onset arrhythmogenic right ventricular cardiomyopathy (ARVC).

BACKGROUND

Although ARVC is increasingly recognized in children, pediatric ARVC cohorts remain underrepresented in the literature.

METHODS

This study included 12 probands with pediatric-onset ARVC (aged <18 years at diagnosis) and 68 pediatric relatives (aged <18 years at first evaluation) referred for cascade screening. ARVC diagnosis was based on 2010 Task Force Criteria. Clinical presentation, diagnostic testing, and outcomes (sustained ventricular tachycardia [VT]; heart failure) were ascertained. Predictors of adverse outcome were determined by using univariable logistic regression.

RESULTS

Pediatric-onset ARVC was diagnosed in 12 probands and 12 (18%) relatives at a median age of 16.6 years (interquartile range: 13.8-17.4 years), whereas 12 (18%) relatives reached ARVC diagnosis as adults (median age, 22.0 years; interquartile range: 20.0-26.7 years). Sudden cardiac death/arrest was the first disease manifestation in 3 (25%) probands and 3 (4%) relatives. In patients without ARVC diagnosis at presentation (n = 61), electrocardiogram and Holter monitoring abnormalities occurred before development of imaging Task Force Criteria (7.3 ± 5.0 years vs 8.4 ± 5.0 years). Clinical course was characterized by sustained VT (91%) and heart failure (36%) in probands, which were rare in relatives (2% and 0%, respectively). Male sex (P < 0.01), T-wave inversion V₁-V₃ (P < 0.01), premature ventricular complexes/runs (P ≤ 0.01), and decrease in biventricular ejection fraction (P ≤ 0.01) were associated with VT occurrence.

CONCLUSIONS

Pediatric ARVC carries high arrhythmic risk, especially in probands. Disease progression is particularly observed on electrocardiogram or Holter monitoring. Arrhythmic events are associated with male sex, T-wave inversions, premature ventricular complexes/runs, and reduced biventricular ejection fraction.

Arrhythmogenic cardiomyopathy in children according to "Padua criteria": Single pediatric center experience

INTRODUCTION

The aim of this study was to report clinical and arrhythmic features in a pediatric population affected by arrhythmogenic cardiomyopathy (ACM). Moreover, we assessed the concordance between the 2010 International Task Force criteria (ITF) and the 2020 Padua criteria.

METHODS

Inclusion criteria were "definite" or "borderline" ACM diagnosed according to the "Padua criteria" in patients <18 years old. History, electrocardiograms, ECG-holter monitorings, exercise testings, imaging investigations, electrophysiological studies, genetic testings and follow-up data were collected.

RESULTS

We enrolled 21 patients (mean age 13.9 ± 2 years). Most of them presented for minor arrhythmias. Premature ventricular complexes burden was 7.9 ± 10%. Cardiac magnetic resonance (19/21, 90.5% patients) showed right ventricular (RV) dilatation, wall motion abnormalities and late gadolinium enhancement (LGE) of both ventricles as predominant features [in 9 patients (52.9%) LGE left ventricle]. Genetic results (19/21 patient) showed compound heterozygous variants in 3/19 patients (15.8%), digenic in 3/19 (15.8%) and single in 6/19 (31.6%). Cardiac defibrillator (ICD) was indicated in 15 patients (71.4%): 6 in class I, 7 in class IIa, 2 in class IIb. Appropriate shocks occurred in 2 patients (13.3%), follow-up 5.46 ± 3.17 years According to 2010 ITF criteria: among the 18 patients with a "definite" ACM diagnosis, one patient would have had a "borderline" diagnosis, three a "possible" diagnosis and one no diagnosis and among the three patients with "borderline" diagnosis two would have had a "possible" diagnosis.

CONCLUSIONS

Pediatric ACM can be diagnosed in the majority of cases secondary to incidental finding of simple ventricular arrhythmias. PVC burden is low and exercise induced arrhythmias rarely occur. Few patients with ICD experience appropriate shocks. "Padua criteria" improve the diagnostic accuracy.

Arrhythmogenic right ventricular cardiomyopathy in the pediatric population

PURPOSE OF REVIEW

Review the current state of the art of arrhythmogenic right ventricular cardiomyopathy (ARVC) diagnosis and risk stratification in the pediatric population.

RECENT FINDINGS

ARVC is an inherited cardiomyopathy characterized by progressive myocyte loss and fibrofatty replacement of predominantly the right ventricle and high risk of ventricular arrhythmias and sudden cardiac death (SCD). ARVC is one of the leading causes of arrhythmic cardiac arrest in young people. Early diagnosis and accurate risk assessment are challenging, especially in children who often exhibit little to no phenotype, even if genotype positive. Multimodal imaging provides more detailed assessment of the right ventricle and has been shown in pediatric patients to identify earlier preclinical disease expression. Identification of patients with ARVC allows the clinician to intervene early with appropriate exercise restrictions, even if genotype positive only without phenotypic expression. Emphasis should be placed on stratifying the patient's risk of ventricular arrhythmias and SCD.

SUMMARY

ARVC is a challenging diagnosis to make in adolescents who often do not exhibit clinical symptoms. Newer multimodal imaging techniques and improvements in genetic testing and biomarkers should help improve early diagnosis. Exercise restriction for children with ARVC has been shown to reduce disease advancement and decreases the risk of a life-threatening event.

Evaluating the 12-Lead Electrocardiogram for Diagnosing ARVC in Young Populations: Implications for Preparticipation Screening of Athletes

Background

Arrhythmogenic right-ventricular cardiomyopathy (ARVC) is an identified cause of sport-related sudden cardiac arrest (SCA). Identifying athletes with ARVC and restricting them from exercise is believed to reduce the risk of SCA. The electrocardiogram (ECG) is considered to be an important component of screening for ARVC; however, the sensitivity of the 12-lead ECG to identify ARVC in young asymptomatic persons is unknown.

Methods

In this retrospective study, we identified 70 patients (49 ARVC-positive, based on Task Force Criteria, and 21 age-matched ARVC-negative persons from a paediatric arrhythmia database (<18 years of age); ECGs were analyzed for abnormalities, based on International Criteria for Interpretation of ECGs in Athletes, and ECG findings were adjudicated by group consensus.

Results

Of the 49 ARVC-positive patients (median age: 17 [interquartile range: 16-18], 65% male), 22% were found to have abnormal ECGs; the most common ECG findings were T-wave inversions. Patients with symptoms were more likely to have abnormal ECGs than asymptomatic patients (28% compared with 17%, respectively; P = 0.002). Of 16 gene-positive patients, 31% had abnormal ECGs. Patients with abnormal ECGs had larger right-ventricular end-diastolic volume indexes on magnetic resonance imaging than those with normal ECGs (P = 0.03).

Conclusions

The ECG was insensitive for detecting ARVC in young (age <18 years), asymptomatic patients, and is unlikely to provide significant diagnostic value for identifying ARVC on routine preparticipation screening of adolescent athletes.

Arrhythmogenic Right Ventricular Cardiomyopathy in Pediatric Patients: An Important but Underrecognized Clinical Entity

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiomyopathy characterized by fibrofatty infiltration of predominantly the right ventricular (RV) myocardium. Affected patients typically present as young adults with hemodynamically stable ventricular tachycardia, although pediatric cases are increasingly recognized. These young subjects often have a more severe phenotype with a high risk of sudden cardiac death (SCD) and progression toward heart failure. Diagnosis of ARVC is made by combining multiple sources of information as prescribed by the consensus-based Task Force Criteria. The description of Naxos disease, a fully penetrant autosomal recessive disorder that is associated with ARVC and a cutaneous phenotype of palmoplantar keratoderma and wooly hair facilitated the identification of the genetic cause of ARVC. At present, approximately 60% of patients are found to carry a pathogenic variant in one of five genes associated with the cardiac desmosome. The incomplete penetrance and variable expressivity of these variants however implies an important role for environmental factors, of which participation in endurance exercise is a strong risk factor. Since there currently is no definite cure for ARVC, disease management is directed toward symptom reduction, delay of disease progression, and prevention of SCD. This clinically focused review describes the spectrum of ARVC among children and adolescents, the genetic architecture underlying this disease, the cardio-cutaneous syndromes that led to its identification, and current diagnostic and therapeutic strategies in pediatric ARVC subjects.

Early Left Ventricular Involvement Detected by Cardiovascular Magnetic Resonance Feature Tracking in Arrhythmogenic Right Ventricular Cardiomyopathy: The Effects of Left Ventricular Late Gadolinium Enhancement and Right Ventricular Dysfunction

Background

Left ventricular (LV) involvement is common in arrhythmogenic right ventricular cardiomyopathy (ARVC). We aim to evaluate LV involvement in ARVC patients by cardiovascular magnetic resonance feature tracking.

Methods and Results

Sixty‐eight patients with ARVC and 30 controls were prospectively enrolled. ARVC patients were divided into 2 subgroups: the preserved LV ejection fraction (LVEF) group (LVEF ≥55%, n=27) and the reduced LVEF group (LVEF <55%, n=41). Cardiovascular magnetic resonance with late gadolinium enhancement (LGE) and cardiovascular magnetic resonance feature tracking were performed in all subjects. LV global and regional (basal, mid, apical) peak strain (PS) in radial, circumferential and longitudinal directions were assessed, respectively. Right ventricular global PS in three directions were also analyzed. Compared with the controls, LV global and regional PS were all significantly impaired in the reduced LVEF group (all P<0.05). However, only LV global longitudinal PS as well as mid and apical longitudinal PS were impaired in the preserved LVEF group (all P<0.05), and all these parameters were significantly associated with right ventricular global radial PS (r=−0.47, −0.47, and −0.49, respectively, all P<0.001). The reduced LVEF group showed significantly higher prevalence of LGE (95.10% versus 63.00%, P=0.002) than the preserved LVEF group. Moreover, LV radial PS was significantly reduced in LV segments with LGE (33.15±20.42%, n=46) than those without LGE (41.25±15.98%, n=386) in the preserved LVEF group (P=0.016).

Conclusions

In patients with ARVC, cardiovascular magnetic resonance feature tracking could detect early LV dysfunction, which was associated with LV myocardial LGE and right ventricular dysfunction.

Usefulness of three-dimensional echocardiography for the assessment of ventricular function in children: Comparison with cardiac magnetic resonance, with a focus on patients with arrhythmia

BACKGROUND

Focusing on patients with arrhythmia, the aims of this study was to assess ventricular function in children using three-dimensional echocardiography (3D-ECHO) and to compare the results to those obtained with cardiac magnetic resonance (CMR).

METHODS

The study group consisted of 43 children in whom 3D-ECHO and CMR were performed. Twenty-five patients had a ventricular arrhythmia, 7 left ventricular cardiomyopathies, 9 proved to be healthy. In all children, 3D-ECHO (offline analysis) was used to assess ventricular ejection fraction (EF). The results were compared to CMR using the Bland-Altman analysis and linear regression. The Student paired T-test was used to compare of means between both modalities.

RESULTS

The relation between the results derived from both methods is linear (for left ventricle: estimated slope = 1.031, p < 0.0001, R-squared = 0.998; for right ventricle: estimated slope = 0.993, p < 0.0001, R-squared = 0.998). In spite of minimal mean differences between results for both ventricles and narrow 95% confidence intervals, the paired t-test proved those differences not to be significant (p > 0.05) for the right ventricle but statistically significant (p < 0.05) for the left ventricle, for which the left ventricular EF calculated in 3D-ECHO was systematically underestimated with a mean difference of -1.8% ± 2.6% (p < 0.0001).

CONCLUSIONS

Three-dimensional echocardiography assessment of both left and right ventricular EF in children showed high significant correlation and agreement with CMR. 3D-ECHO could be a valuable tool in follow-up of children with arrhythmic disorders requiring regular assessment of ventricular function.