Diagnosing arrhythmogenic right ventricular cardiomyopathy by 2010 Task Force Criteria: clinical performance and simplified practical implementation

A right ventricular bulge: A clinical dilemma in diagnosis

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited disease characterized by progressive fibrofatty tissue replacement of the myocardium. Asymptomatic individuals can often present for the first time with acute cardiac symptoms, such as syncope and ventricular arrhythmias or sudden cardiac death (SCD), which can occur in young and athletic populations. In the field of inherited cardiomyopathies, ARVC is one of the most challenging to diagnose due to its variable expressivity, incomplete penetrance, and lack of specific, unique diagnostic criteria. Without additional clinical findings or context, current imaging modalities are unable to definitively distinguish ARVC from other disease entities. Right ventricular (RV) structural changes can lead to prominent ARVC features. An important component of the 2010 revised task force criteria (TFC) is the assessment of RV wall motion contraction by echocardiography; however, this can be difficult to assess. This case report explores the diagnostic criteria used for ARVC and the role of RV wall motion contraction in the diagnosis.

Improved diagnosis of arrhythmogenic right ventricular cardiomyopathy using electrocardiographic deep learning

BACKGROUND

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare genetic heart disease associated with life-threatening ventricular arrhythmias. Diagnosis of ARVC is based on the 2010 Task Force Criteria (TFC), application of which often requires clinical expertise at specialized centers.

OBJECTIVE

The purpose of this study was to develop and validate an electrocardiogram (ECG) deep learning (DL) tool for ARVC diagnosis.

METHODS

ECGs of patients referred for ARVC evaluation were used to develop (n = 551 [80.1%]) and test (n = 137 [19.9%]) an ECG-DL model for prediction of TFC-defined ARVC diagnosis. The ARVC ECG-DL model was externally validated in a cohort of patients with pathogenic or likely pathogenic (P/LP) ARVC gene variants identified through the Geisinger MyCode Community Health Initiative (N = 167).

RESULTS

Of 688 patients evaluated at Johns Hopkins Hospital (JHH) (57.3% male, mean age 40.2 years), 329 (47.8%) were diagnosed with ARVC. Although ARVC diagnosis made by referring cardiologist ECG interpretation was unreliable (c-statistic 0.53; confidence interval [CI] 0.52-0.53), ECG-DL discrimination in the hold-out testing cohort was excellent (0.87; 0.86-0.89) and compared favorably to that of ECG interpretation by an ARVC expert (0.85; 0.84-0.86). In the Geisinger cohort, prevalence of ARVC was lower (n = 17 [10.2%]), but ECG-DL-based identification of ARVC phenotype remained reliable (0.80; 0.77-0.83). Discrimination was further increased when ECG-DL predictions were combined with non-ECG-derived TFC in the JHH testing (c-statistic 0.940; 95% CI 0.933-0.948) and Geisinger validation (0.897; 95% CI 0.883-0.912) cohorts.

CONCLUSION

ECG-DL augments diagnosis of ARVC to the level of an ARVC expert and can differentiate true ARVC diagnosis from phenotype-mimics and at-risk family members/genotype-positive individuals.

Natural Course of Electrocardiographic Features in Arrhythmogenic Right Ventricular Cardiomyopathy and Their Relation to Ventricular Arrhythmic Events

BACKGROUND

Electrocardiographic abnormalities are common in arrhythmogenic right ventricular cardiomyopathy and are included in the 2010 Task Force Criteria. Their time course, however, remains uncertain. In this retrospective observational study, we aimed to assess the long-term evolution of electrocardiographic characteristics and their relation to ventricular arrhythmias.

METHODS AND RESULTS

Three hundred fifty-three patients with arrhythmogenic right ventricular cardiomyopathy as per the 2010 Task Force Criteria with 6871 automatically processed 12-lead digital ECGs were included. The relationship between the electrocardiographic parameters and the risk of ventricular arrhythmias was assessed at 10 years from the first ECG. Electrocardiographic parameters were compared between the first contact ECG, the ECG at diagnosis, and the most recent ECG. Median time between the first and the latest ECG was 6 [interquartile range, 1-14] years. Reductions of QRS voltage, R- and T-wave amplitudes between the first, diagnostic, and the latest ECGs were observed across precordial and extremity leads. Mean QRS duration increased from 96 to 102 ms (P<0.001), terminal activation duration (V1) from 47 to 52 ms (P<0.001), and QTc from 419 to 432 ms (P<0.001). T-wave inversions in leads V3 to V6 and aVF at first ECG were associated with ventricular arrhythmias (adjusted hazard ratio [HRadj][V3], 2.03 [95% CI, 1.23-3.34] and HRadj[aVF], 1.87 [95% CI, 1.13-3.08]).

CONCLUSIONS

Depolarization and repolarization parameters evolved over time in patients with arrhythmogenic right ventricular cardiomyopathy, supporting the progressive nature of arrhythmogenic right ventricular cardiomyopathy. Electrocardiographic abnormalities may be detected before diagnosis and might, although not fulfilling the 2010 Task Force Criteria, be markers of early disease. T-wave inversion in leads V3 or aVF before diagnosis was associated with ventricular arrhythmias during follow-up.

High-Fat Diet Augments Myocardial Inflammation and Cardiac Dysfunction in Arrhythmogenic Cardiomyopathy

Arrhythmogenic cardiomyopathy (ACM) is a familial heart disease characterized by cardiac dysfunction, arrhythmias, and myocardial inflammation. Exercise and stress can influence the disease's progression. Thus, an investigation of whether a high-fat diet (HFD) contributes to ACM pathogenesis is warranted. In a robust ACM mouse model, 8-week-old Desmoglein-2 mutant (Dsg2mut/mut) mice were fed either an HFD or rodent chow for 8 weeks. Chow-fed wildtype (WT) mice served as controls. Echo- and electrocardiography images pre- and post-dietary intervention were obtained, and the lipid burden, inflammatory markers, and myocardial fibrosis were assessed at the study endpoint. HFD-fed Dsg2mut/mut mice showed numerous P-wave perturbations, reduced R-amplitude, left ventricle (LV) remodeling, and reduced ejection fraction (%LVEF). Notable elevations in plasma high-density lipoprotein (HDL) were observed, which correlated with the %LVEF. The myocardial inflammatory adipokines, adiponectin (AdipoQ) and fibroblast growth factor-1, were substantially elevated in HFD-fed Dsg2mut/mut mice, albeit no compounding effect was observed in cardiac fibrosis. The HFD not only potentiated cardiac dysfunction but additionally promoted adverse cardiac remodeling. Further investigation is warranted, particularly given elevated AdipoQ levels and the positive correlation of HDL with the %LVEF, which may suggest a protective effect. Altogether, the HFD worsened some, but not all, disease phenotypes in Dsg2mut/mut mice. Notwithstanding, diet may be a modifiable environmental factor in ACM disease progression.

Artificial intelligence-enhanced electrocardiogram for arrhythmogenic right ventricular cardiomyopathy detection

Aims

ECG abnormalities are often the first signs of arrhythmogenic right ventricular cardiomyopathy (ARVC) and we hypothesized that an artificial intelligence (AI)-enhanced ECG could help identify patients with ARVC and serve as a valuable disease-detection tool.

Methods and results

We created a convolutional neural network to detect ARVC using a 12-lead ECG. All patients with ARVC who met the 2010 task force criteria and had disease-causative genetic variants were included. All case ECGs were randomly assigned in an 8:1:1 ratio into training, validation, and testing groups. The case ECGs were age- and sex-matched with control ECGs at our institution in a 1:100 ratio. Seventy-seven patients (51% male; mean age 47.2 ± 19.9), including 56 patients with PKP2, 7 with DSG2, 6 with DSC2, 6 with DSP, and 2 with JUP were included. The model was trained using 61 case ECGs and 5009 control ECGs; validated with 7 case ECGs and 678 control ECGs and tested in 22 case ECGs and 1256 control ECGs. The sensitivity, specificity, positive and negative predictive values of the model were 77.3, 62.9, 3.32, and 99.4%, respectively. The area under the curve for rhythm ECG and median beat ECG was 0.75 and 0.76, respectively.

Conclusion

Our study found that the model performed well in excluding ARVC and supports the concept that the AI ECG can serve as a biomarker for ARVC if a larger cohort were available for network training. A multicentre study including patients with ARVC from other centres would be the next step in refining, testing, and validating this algorithm.

Right Ventricular Function in Arrhythmogenic Right Ventricular Cardiomyopathy: Potential Value of Strain Echocardiography

Arrhythmogenic right ventricular cardiomyopathy is an inherited cardiomyopathy, characterized by abnormal cell adhesions, disrupted intercellular signaling, and fibrofatty replacement of the myocardium. These changes serve as a substrate for ventricular arrhythmias, placing patients at risk of sudden cardiac death, even in the early stages of the disease. Current echocardiographic criteria for diagnosing arrhythmogenic right ventricular cardiomyopathy lack sensitivity, but novel markers of cardiac deformation are not subject to the same technical limitations as current guideline-recommended measures. Measuring cardiac deformation using speckle tracking allows for meticulous quantification of global systolic function, regional function, and dyssynchronous contraction. Consequently, speckle tracking to quantify myocardial strain could potentially be useful in the diagnostic process for the determination of disease progression and to assist risk stratification for ventricular arrhythmias and sudden cardiac death. This narrative review provides an overview of the potential use of different myocardial right ventricular strain measures for characterizing right ventricular dysfunction in arrhythmogenic right ventricular cardiomyopathy and its utility in assessing the risk of ventricular arrhythmias.

Incremental Diagnostic Value of Right Ventricular Strain Analysis in Arrhythmogenic Right Ventricular Cardiomyopathy

BACKGROUND

Strain analysis is a sensitive method for the assessment of ventricular structural or functional alterations. The authors aimed to determine whether right ventricular (RV) strain parameters can discriminate patients with revised Task Force Criteria-diagnosed arrhythmogenic RV cardiomyopathy (ARVC) incremental to the existing cardiovascular magnetic resonance (CMR) criteria, thus improving the diagnostic yield of CMR in ARVC.

METHODS AND RESULTS

A total of 74 patients with revised Task Force Criteria-diagnosed ARVC (37 borderline and 37 definite) and 37 controls were retrospectively enrolled for analysis. Using CMR feature tracking, RV global longitudinal (GLS), circumferential, and radial strain of all participants were evaluated. Compared with controls, the study patients demonstrated significantly impaired global biventricular strain in all 3 directions (all P<0.001). Receiver operating characteristic curve analysis indicated that RV GLS was the strongest discriminator among all RV strain parameters for the identification of patients with ARVC (area under the curve, 0.92). Using the Youden index, the authors determined RV GLS ≥-19.95% as the diagnostic criterion of ARVC. In patients diagnosed with borderline ARVC according to revised Task Force Criteria but with no or only minor CMR criteria, there were >50% presenting with impaired RV GLS. When both conventional criteria and RV GLS were considered together, this new diagnostic method demonstrated an overall diagnostic accuracy of 90%. The likelihood ratio test showed a significant incremental diagnostic value of RV GLS (P=0.02) over the existing CMR major criteria.

CONCLUSIONS

The current study showed an improved diagnostic accuracy when both RV GLS and the existing CMR criteria were considered together, especially for patients with borderline diagnosis, suggesting the incremental value of strain analysis to the initial assessment of ARVC.

Phenotyping heart failure by genetics and associated conditions

Heart failure is a highly heterogeneous disease, and genetic testing may allow phenotypic distinctions that are incremental to those obtainable from imaging. Advances in genetic testing have allowed for the identification of deleterious variants in patients with specific heart failure phenotypes (dilated cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, and hypertrophic cardiomyopathy), and many of these have specific treatment implications. The diagnostic yield of genetic testing in heart failure is modest, and many rare variants are associated with incomplete penetrance and variable expressivity. Environmental factors and co-morbidities have a large role in the heterogeneity of the heart failure phenotype. Future endeavours should concentrate on the cumulative impact of genetic polymorphisms in the development of heart failure.

Recurrent Syncope in a Patient With Arrhythmogenic Right Ventricular Cardiomyopathy

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an autosomal inherited cardiac condition characterized by fibroadipose tissue replacement of the right ventricular muscle, leading to structural changes and a high risk for ventricular arrhythmias, a gradual decline in right ventricular function, and sudden cardiac death. ARVC has an autosomal dominant inheritance pattern with variable expression among patients, typically affecting young adults. Genetic mutations affecting the cardiac desmosome genes have been widely reported. Intense exercise has been hypothesized as one of the drivers of ARVC's pathogenesis. Due to its non-specific presentation, it can become a diagnostic challenge for physicians with delayed care. We report a case of a male adult with a history of recurrent syncope and atypical chest pain who developed ventricular tachycardia on admission. This case aims to highlight the unspecific manifestations of ARVC and its main electrocardiographic features for an early diagnosis.

Monitoring of Myocardial Involvement in Early Arrhythmogenic Right Ventricular Cardiomyopathy Across the Age Spectrum

BACKGROUND

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is characterized by fibrofatty replacement of primarily the right ventricular myocardium, a substrate for life-threatening ventricular arrhythmias (VAs). Repeated cardiac imaging of at-risk relatives is important for early disease detection. However, it is not known whether screening should be age-tailored.

OBJECTIVES

The goal of this study was to assess the need for age-tailoring of follow-up protocols in early ARVC by evaluating myocardial disease progression in different age groups.

METHODS

We divided patients with early-stage ARVC and genotype-positive relatives without overt structural disease and VA at first evaluation into 3 groups: age <30 years, 30 to 50 years, and ≥50 years. Longitudinal biventricular deformation characteristics were used to monitor disease progression. To link deformation abnormalities to underlying myocardial disease substrates, Digital Twins were created using an imaging-based computational modeling framework.

RESULTS

We included 313 echocardiographic assessments from 82 subjects (57% female, age 39 ± 17 years, 10% probands) during 6.7 ± 3.3 years of follow-up. Left ventricular global longitudinal strain slightly deteriorated similarly in all age groups (0.1%-point per year [95% CI: 0.05-0.15]). Disease progression in all age groups was more pronounced in the right ventricular lateral wall, expressed by worsening in longitudinal strain (0.6%-point per year [95% CI: 0.46-0.70]) and local differences in myocardial contractility, compliance, and activation delay in the Digital Twin. Six patients experienced VA during follow-up.

CONCLUSIONS

Disease progression was similar in all age groups, and sustained VA also occurred in patients aged >50 years without overt ARVC phenotype at first evaluation. Unlike recommended by current guidelines, our study suggests that follow-up of ARVC patients and relatives should not stop at older age.

Body surface potential mapping detects early disease onset in plakophilin-2-pathogenic variant carriers

AIMS

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a progressive inherited cardiac disease. Early detection of disease and risk stratification remain challenging due to heterogeneous phenotypic expression. The standard configuration of the 12 lead electrocardiogram (ECG) might be insensitive to identify subtle ECG abnormalities. We hypothesized that body surface potential mapping (BSPM) may be more sensitive to detect subtle ECG abnormalities.

METHODS AND RESULTS

We obtained 67 electrode BSPM in plakophilin-2 (PKP2)-pathogenic variant carriers and control subjects. Subject-specific computed tomography/magnetic resonance imaging based models of the heart/torso and electrode positions were created. Cardiac activation and recovery patterns were visualized with QRS- and STT-isopotential map series on subject-specific geometries to relate QRS-/STT-patterns to cardiac anatomy and electrode positions. To detect early signs of functional/structural heart disease, we also obtained right ventricular (RV) echocardiographic deformation imaging. Body surface potential mapping was obtained in 25 controls and 42 PKP2-pathogenic variant carriers. We identified five distinct abnormal QRS-patterns and four distinct abnormal STT-patterns in the isopotential map series of 31/42 variant carriers. Of these 31 variant carriers, 17 showed no depolarization or repolarization abnormalities in the 12 lead ECG. Of the 19 pre-clinical variant carriers, 12 had normal RV-deformation patterns, while 7/12 showed abnormal QRS- and/or STT-patterns.

CONCLUSION

Assessing depolarization and repolarization by BSPM may help in the quest for early detection of disease in variant carriers since abnormal QRS- and/or STT-patterns were found in variant carriers with a normal 12 lead ECG. Because electrical abnormalities were observed in subjects with normal RV-deformation patterns, we hypothesize that electrical abnormalities develop prior to functional/structural abnormalities in ARVC.

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.

The pivotal role of ECG in cardiomyopathies

Cardiomyopathies are a heterogeneous group of pathologies characterized by structural and functional alterations of the heart. Recent technological advances in cardiovascular imaging offer an opportunity for deep phenotypic and etiological definition. Electrocardiogram (ECG) is the first-line diagnostic tool in the evaluation of both asymptomatic and symptomatic individuals. Some electrocardiographic signs are pathognomonic or fall within validated diagnostic criteria of individual cardiomyopathy such as the inverted T waves in right precordial leads (V1-V3) or beyond in individuals with complete pubertal development in the absence of complete right bundle branch block for the diagnosis of arrhythmogenic cardiomyopathy of the right ventricle (ARVC) or the presence of low voltages typically seen in more than 60% of patients with amyloidosis. Most other electrocardiographic findings such as the presence of depolarization changes including QRS fragmentation, the presence of epsilon wave, the presence of reduced or increased voltages as well as alterations in the repolarization phase including the negative T waves in the lateral leads, or the profound inversion of the T waves or downsloping of the ST tract are more non-specific signs which can however raise the clinical suspicion of cardiomyopathy in order to initiate a diagnostic procedure especially using imaging techniques for diagnostic confirmation. Such electrocardiographic alterations not only have a counterpart in imaging investigations such as evidence of late gadolinium enhancement on magnetic resonance imaging, but may also have an important prognostic value once a definite diagnosis has been made. In addition, the presence of electrical stimulus conduction disturbances or advanced atrioventricular blocks that can be seen especially in conditions such as cardiac amyloidosis or sarcoidosis, or the presence of left bundle branch block or posterior fascicular block in dilated or arrhythmogenic left ventricular cardiomyopathies are recognized as a possible expression of advanced pathology. Similarly, the presence of ventricular arrhythmias with typical patterns such as non-sustained or sustained ventricular tachycardia of LBBB morphology in ARVC or non-sustained or sustained ventricular tachycardia with an RBBB morphology (excluding the "fascicular pattern") in arrhythmogenic left ventricle cardiomyopathy could have a significant impact on the course of each disease. It is therefore clear that a learned and careful interpretation of ECG features can raise suspicion of the presence of a cardiomyopathy, identify diagnostic "red flags" useful for orienting the diagnosis toward specific forms, and provide useful tools for risk stratification. The purpose of this review is to emphasize the important role of the ECG in the diagnostic workup, describing the main ECG findings of different cardiomyopathies.

The R″ wave in V1 and the negative terminal QRS vector in aVF combine to a novel 12-lead ECG algorithm to identify slow conducting anatomical isthmus 3 in patients with tetralogy of Fallot

AIMS

Patients with repaired tetralogy of Fallot (rTOF) have an increased risk of ventricular tachycardia (VT), with slow conducting anatomical isthmus (SCAI) 3 as dominant VT substrate. In patients with right bundle branch block (RBBB), SCAI 3 leads to local activation delay with a shift of terminal RV activation towards the lateral RV outflow tract which may be detected by terminal QRS vector changes on sinus rhythm electrocardiogram (ECG).

METHODS AND RESULTS

Consecutive rTOF patients aged ≥16 years with RBBB who underwent electroanatomical mapping at our institution between 2017-2022 and 2010-2016 comprised the derivation and validation cohort, respectively. Forty-six patients were included in the derivation cohort (aged 40±15 years, QRS duration 165±23 ms). Among patients with SCAI 3 (n = 31, 67%), 17 (55%) had an R″ in V1, 18 (58%) had a negative terminal QRS portion (NTP) ≥80 ms in aVF, and 12 (39%) had both ECG characteristics, compared to only 1 (7%), 1 (7%), and 0 patient without SCAI, respectively.Combining R″ in V1 and/or NTP ≥80 ms in aVF into a diagnostic algorithm resulted in a sensitivity of 74% and specificity of 87% in detecting SCAI 3. The inter-observer agreement for the diagnostic algorithm was 0.875. In the validation cohort [n = 33, 18 (55%) with SCAI 3], the diagnostic algorithm had a sensitivity of 83% and specificity of 80% for identifying SCAI 3.

CONCLUSION

A sinus rhythm ECG-based algorithm including R″ in V1 and/or NTP ≥80 ms in aVF can identify rTOF patients with a SCAI 3 and may contribute to non-invasive risk stratification for VT.

Idiopathic Isolated Right Ventricular Cardiomyopathy: A Rare Case Report

Idiopathic isolated right ventricular cardiomyopathy is an extremely rare cause of right ventricular failure. Here, we report a case of 65-year-old male presented with chief complaints of dyspnea, fatigue, and bilateral pedal edema for the last 6 months. On clinical evaluation, grade II/III pansystolic murmur was present in left parasternal area. Investigations and imaging revealed dilated right atrium and ventricle with normal pulmonary artery pressure without any etiology. Magnetic resonance imaging ruled out other common causes of right ventricular cardiomyopathy; thus, the patient was diagnosed as a case of idiopathic isolated right ventricular cardiomyopathy that is a diagnosis of exclusion.

Towards automatic classification of cardiovascular magnetic resonance Task Force Criteria for diagnosis of arrhythmogenic right ventricular cardiomyopathy

BACKGROUND

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is diagnosed according to the Task Force Criteria (TFC) in which cardiovascular magnetic resonance (CMR) imaging plays an important role. Our study aims to apply an automatic deep learning-based segmentation for right and left ventricular CMR assessment and evaluate this approach for classification of the CMR TFC.

METHODS

We included 227 subjects suspected of ARVC who underwent CMR. Subjects were classified into (1) ARVC patients fulfilling TFC; (2) at-risk family members; and (3) controls. To perform automatic segmentation, a Bayesian Dilated Residual Neural Network was trained and tested. Performance of automatic versus manual segmentation was assessed using Dice-coefficient and Hausdorff distance. Since automatic segmentation is most challenging in basal slices, manual correction of the automatic segmentation in the most basal slice was simulated (automatic^-basal). CMR TFC calculated using manual and automatic^-basal segmentation were compared using Cohen's Kappa (κ).

RESULTS

Automatic segmentation was trained on CMRs of 70 subjects (39.6 ± 18.1 years, 47% female) and tested on 157 subjects (36.9 ± 17.6 years, 59% female). Dice-coefficient and Hausdorff distance showed good agreement between manual and automatic segmentations (≥ 0.89 and ≤ 10.6 mm, respectively) which further improved after simulated correction of the most basal slice (≥ 0.92 and ≤ 9.2 mm, p < 0.001). Pearson correlation of volumetric and functional CMR measurements was good to excellent (automatic (r = 0.78-0.99, p < 0.001) and automatic^-basal (r = 0.88-0.99, p < 0.001) measurements). CMR TFC classification using automatic^-basal segmentations was comparable to manual segmentations (κ 0.98 ± 0.02) with comparable diagnostic performance.

CONCLUSIONS

Combining automatic segmentation of CMRs with correction of the most basal slice results in accurate CMR TFC classification of subjects suspected of ARVC.

NON-COMPACTION CARDIOMYOPATHY: ISSUES, CONTRADICTIONS AND SEARCH FOR EFFECTIVE DIAGNOSTIC CRITERIA. LITERATURE REVIEW. PART 1

Active research of non-compaction cardiomyopathy (NCM) has been going on for more than 30 years. A significant amount of information has been accumulated that is familiar to a much larger number of specialists than in the most recent past. Despite this, numerous issues remain unresolved, ranging from classification (congenital or acquired, nosology or morphological phenotype) to the ongoing search for clear diagnostic criteria that separate NCM from physiological hypertrabecularity and secondary non-compaction myocardium with the background of existing chronic processes. Meanwhile, a high risk of adverse cardiovascular events in a certain group of people with NCM is quite high. These patients need timely and often quite aggressive therapy. This review of sources of scientific and practical information is devoted to the current aspects of the classification, extremely diverse clinical picture, extremely complex genetic and instrumental diagnosis of NCM, and the possibilities of its treatment. The purpose of this review is to analyze current ideas about the controversial problems of non-compaction cardiomyopathy. The material for its preparation is the numerous sources of databases Web Science, PubMed, Google Scholar, eLIBRARY. As a result of their analysis, the authors tried to identify and summarize the main problems of the NCM and identify the ways to resolve them.

Clinical and echocardiographic evolution of patients with arrhythmogenic cardiomyopathy before heart transplantation

BACKGROUND

Arrhythmogenic cardiomyopathy (ACM) is an inherited cardiomyopathy characterized by fibrofatty myocardial replacement, and accurate diagnosis can be challenging. The clinical course of patients expressing a severe phenotype of the disease needing heart transplantation (HTx) is not well described in the literature. Therefore, this study aims to describe the clinical and echocardiographic evolution of patients with ACM necessitating HTx.

METHODS

We retrospectively studied all patients who underwent HTx in our institution between 1998 and 2019 with a definite diagnosis of ACM according to the explanted heart examination.

RESULTS

Ten patients with confirmed ACM underwent HTx. Only four of them had a diagnosis of ACM before HTx. These patients were 28 ± 15 years old at the time of their first symptoms. Patients received a diagnosis of heart failure (HF) after 5.9 ± 8.7 years of symptom evolution. The mean age at transplantation was 40 ± 17 years old. All the patients experienced ventricular tachycardia (VT) at least once before their HTx and 50% were resuscitated after sudden death. The mean left ventricular ejection at diagnosis and before transplantation was similar (32% ± 21% vs. 35.0% ± 19.3%, p = NS). Right ventricular dysfunction was present in all patients at the time of transplantation.

CONCLUSION

Patients with ACM necessitating HTx show a high burden of ventricular arrhythmias and frequently present a biventricular involvement phenotype, making early diagnosis challenging. HF symptoms are the most frequent reason leading to the decision to transplant.

Incremental value of the signal-averaged ECG for diagnosing arrhythmogenic cardiomyopathy

BACKGROUND

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is currently diagnosed using a combination of clinical features, imaging, electrocardiography, and genetic investigations. An abnormal signal-averaged electrocardiogram (SAECG) is defined as a minor diagnostic criterion by the 2010 Task Force Criteria, but doubts remain about the value of this investigation.

OBJECTIVE

We evaluated the utility of the SAECG in diagnosing ARVC using the Canadian Arrhythmogenic Right Ventricular Cardiomyopathy Registry, a population representative registry of probands with ARVC and relatives, less influenced by referral bias.

METHODS

Probands with ARVC and family members from the Canadian Arrhythmogenic Right Ventricular Cardiomyopathy Registry underwent phenotype review. SAECG parameters were compared individually and in combination between those with varying degrees of ARVC severity and healthy controls (family members of probands with ARVC and unexplained sudden death, free of evidence of cardiac disease).

RESULTS

A total of 196 patients with ARVC and 205 controls were included (mean age 44 ± 15 years; 186 of 401 men [46%]). SAECG abnormalities were seen in 83 of 205 controls (40%), 33 of 68 patients with ARVC and mild disease (51%), and 31 of 42 with severe disease (74%). The SAECG associated strongly with imaging abnormalities (major: odds ratio 3.0, 95% confidence interval 1.3-6.9; minor: odds ratio 3.5, 95% confidence interval 0.7-16.5) but not with other aspects of phenotype. Patients carrying pathogenic variants but with minimal phenotype had similar SAECGs to healthy controls (filtered QRS duration 111.2 ± 11.2 ms vs 111 ± 7.6 ms, P = .93; duration of low amplitude signals < 40 μV 32.3 ± 8.9 ms vs 34.2 ± 7.2 ms, P = .32; root mean square of the terminal 40 ms of the filtered QRS complex 43.1 ± 25.2 ms vs 38.2 ± 20.2 ms, P = .38).

CONCLUSION

The SAECG appears to be a surrogate marker for structural abnormalities seen on imaging in those with ARVC. Great caution is required in interpreting SAECG findings in those without other corroborating evidence of an ARVC phenotype.

[Arrhythmogenic right ventricular cardiomyopathy : An update]

Arrhythmogenic right ventricular cardiomyopathy is a hereditary myocardial condition in most cases that affects the right ventricle, but also the left ventricle with variable degree. It predisposes patients to ventricular arrhythmia, heart failure and sudden death. Its diagnosis remains challenging and is mostly based on reference task-force criteria. The latter, divided between major and minor criteria, include structural abnormalities (visualized on echocardiography or cardiac magnetic resonance), electrocardiographic anomalies, ventricular arrythmia documentation, histological proof of fibro-fatty infiltrates within myocardial tissue and family history. Following a correct diagnosis, patient-tailored care is essential. First, implantation of an implantable cardioverter-defibrillator is recommended in case of history of sudden death, sustained ventricular tachycardia or advanced right/left ventricular dysfunction. It should be considered in case of cardiac syncope or non-sustained ventricular tachycardia. Secondly, eviction of high intensity physical activity is mandatory. Finally, beta-blockers are recommended for all patients with clinically manifest arrhythmogenic right ventricular cardiomyopathy.

Myocarditis or inherited disease? - The multifaceted presentation of arrhythmogenic cardiomyopathy

INTRODUCTION

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is now usually referred to as arrhythmogenic cardiomyopathy (ACM) because of the possible left and biventricular affection. In recent years, it has been shown that early-stage ACM, especially in women carrying a disease-causing variant in the DSP gene, may present with clinical signs of myocarditis.

CASE PRESENTATION

The female patient was diagnosed with myocarditis based on arrhythmia and findings on magnetic resonance imaging at the age of 24 years. An additional performed myocardial biopsy confirmed a lymphocytic inflammatory reaction. Subsequently, the patient experienced cardiac arrest because of ventricular fibrillation and was resuscitated. As a result, she received an implantable cardioverter defibrillator, and repeated ablations of recurrent ventricular tachycardia were performed. After four years, molecular genetic testing identified the heterozygous, likely pathogenic nonsense variant c.4789G > T, p.(Glu1597*) in DSP (NM_004415.4). Based on this finding, ACM could be diagnosed, and a heart transplantation was performed only a few months later because of rapid disease progression.

DISCUSSION

Truncating variants in DSP have been associated with fulminant progression of arrhythmia. However, the currently used ARVC task force criteria are inadequate to detect DSP-associated ACM with left dominant presentation. Moreover, the initial diagnosis of myocarditis may distract from a more extensive search for other causes. Consequently, in cases of recurrent or unusually prolonged myocarditis, especially if present without detected pathogens, molecular genetic testing should be considered.

Arrhythmogenic Right Ventricular Cardiomyopathy

Arrhythmogenic right ventricular cardiomyopathy (ARVC) encompasses a group of conditions characterized by right ventricular fibrofatty infiltration, with a predominant arrhythmic presentation. First described in the late 1970s and early 1980s, it is now frequently recognized to have biventricular involvement. The prevalence is ∼1:2,000 to 1:5,000, depending on geographic location, and it has a slight male predominance. The diagnosis of ARVC is determined on the basis of fulfillment of task force criteria incorporating electrophysiological parameters, cardiac imaging findings, genetic factors, and histopathologic features. Risk stratification of patients with ARVC aims to identify those who are at increased risk of sudden cardiac death or sustained ventricular tachycardia. Factors including age, sex, electrophysiological features, and cardiac imaging investigations all contribute to risk stratification. The current management of ARVC includes exercise restriction, β-blocker therapy, consideration for implantable cardioverter-defibrillator insertion, and catheter ablation. This review summarizes our current understanding of ARVC and provides clinicians with a practical approach to diagnosis and management.

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 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.

Endomyocardial Biopsy: The Forgotten Piece in the Arrhythmogenic Cardiomyopathy Puzzle

Background Endomyocardial biopsy (EMB) is part of 2010 Task Force Criteria (TFC) for arrhythmogenic right ventricular cardiomyopathy (ARVC). However, its usage has been curtailed because of its low presumed diagnostic yield, and it is now a poorly used tool. This study aims to analyze the contribution of EMB to the final diagnosis of ARVC. Methods and Results We included 104 consecutive patients evaluated for a suspicion of ARVC, who were referred for EMB. Patients with suspected left dominant pattern were excluded from the primary analysis. Subjects were initially stratified according to TFC without considering EMB. After EMB, patients were reclassified accordingly, and the reclassification rate was calculated. EMB yielded a diagnostic finding in 92 patients (85.5%). After including EMB evaluation, 20 (43%) more patients "at risk" received a definite diagnosis of ARVC. Overall, 59 patients received a definite diagnosis of ARVC, 34% only after EMB. EMB appeared to be the better-performing exam with respect to the final diagnosis (β, 2.2; area uder the curve, 0.73; P<0.05). The reclassification improvement after EMB measured 28%. TFC score increased from 3.5±1.3 to 4.3±1.4 (P<0.001). Notably, active inflammation was present in 6 (10%) patients. Minor complications were reported in only 2% of the cohort. In patients with suspected left-dominant disease, conventional TFC performed poorly. Conclusions Electroanatomic voltage mapping-guided EMB was safe and yielded an optimal diagnostic yield. It allowed upgrading of the diagnosis of nearly one-third of the patients considered "at risk." Classical TFC without EMB performed poorly in patients with the left dominant form of ARVC.

A case of cardiac sarcoidosis with successful heart transplantation after COVID-19 infection

Arrhythmogenic right ventricular cardiomyopathy and cardiac sarcoidosis can both present with ventricular tachycardia. We report a case of a patient whose histological diagnosis was not only confirmed by the transplanted heart but who also underwent successful transplantation after overcoming COVID-19.

Pregnancy in arrhythmogenic cardiomyopathy

Arrhythmogenic cardiomyopathy (AC) is a rare heart muscle disease with a genetic background and autosomal dominant mode of transmission. The clinical manifestation is characterized by ventricular arrhythmias (VA), heart failure (HF) and the risk of sudden cardiac death (SCD). Pregnancy in young female patients with AC represents a challenging condition for the life and family planning of young affected women. In addition to genetic mechanisms that influence the complex pathophysiology of AC, experimental and clinical data have confirmed the pathogenetic role of strenuous exercise and competitive sports in the early onset and rapid progression of AC symptoms and complications. Pregnancy and exercise share a number of physiological aspects of adaptation. In AC, both result in ventricular volume overload and myocardial stretch. Therefore, pregnancy has been postulated as a potential risk factor for HF, VA, SCD, and pregnancy-related obstetric complications in patients with AC. However, the available evidence on pregnancy in AC does not confirm this hypothesis. In most women with AC, pregnancies are well tolerated, uneventful, and follow a benign course. Pregnancy-related symptoms (VA, syncope, HF) and mortality, as well as obstetric complications, are uncommon in AC patients and range in the order of background populations and cohorts with AC and no pregnancy. The number of completed pregnancies is not associated with an acceleration of AC pathology or an increased risk of VA or HF during pregnancy and follow-up. Accordingly, there is no medical indication to advise against pregnancy in patients with AC. Preconditions include stability of rhythm and hemodynamics at baseline, as well as clinical follow-ups and the availability of multidisciplinary expert consultation during pregnancy and postpartum. Genetic counseling is recommended prior to pregnancy for all couples and their families affected by AC.

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: a focused update on diagnosis and risk stratification

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiomyopathy characterised by fibrofatty replacement of predominantly the right ventricle and high risk of ventricular arrhythmias and sudden cardiac death (SCD). Early diagnosis and accurate risk assessment are challenging yet essential for SCD prevention. This manuscript summarises the current state of the art on ARVC diagnosis and risk stratification. Improving the 2010 diagnostic criteria is an ongoing discussion. Several studies suggest that early diagnosis may be facilitated by including deformation imaging ('strain') for objective assessment of wall motion abnormalities, which was shown to have high sensitivity for preclinical disease. Adding fibrofatty replacement detected by late gadolinium enhancement or T1 mapping in cardiac MRI as criterion for diagnosis is increasingly suggested but requires more supporting evidence from consecutive patient cohorts. In addition to the traditional right-dominant ARVC, standard criteria for arrhythmogenic cardiomyopathy (ACM) and arrhythmogenic left ventricular cardiomyopathy (ALVC) are on the horizon. After diagnosis confirmation, the primary management goal is SCD prevention, for which an implantable cardioverter-defibrillator is the only proven therapy. Prior studies determined that younger age, male sex, previous (non-) sustained ventricular tachycardia, syncope, extent of T-wave inversion, frequent premature ectopic beats and lower biventricular ejection fraction are risk factors for subsequent events. Previous implantable cardioverter-defibrillator indication guidelines were however limited to three expert-opinion flow charts stratifying patients in risk groups. Now, two multivariable risk prediction models (arvcrisk.com) combine the abovementioned risk factors to estimate individual risks. Of note, both the flow charts and prediction models require clinical validation studies to determine which should be recommended.

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.

Left Ventricular Dysfunction in Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC): Can We Separate ARVC From Other Arrhythmogenic Cardiomyopathies?

Arrhythmogenic right ventricular cardiomyopathy was first described as a right ventricular disease that is an important cause of death in young adults. However, with the advent of advanced imaging, arrhythmogenic right ventricular cardiomyopathy has been found to commonly have biventricular involvement, and a small portion of patients have left ventricular–dominant forms. On the other hand, a number of primarily left ventricular disease such as sarcoid and myocarditis can be arrhythmogenic and have right ventricular involvement. A few recent publications on arrhythmogenic right ventricular cardiomyopathy cohorts have average left ventricular functions that are comparable to sarcoid or myocarditis cohorts. We review the current literature and compare these cohorts of patients, and call for left ventricular functional criteria for arrhythmogenic right ventricular cardiomyopathy as inherited arrhythmogenic cardiomyopathy.