Family Screening in Dilated Cardiomyopathy: Prevalence, Incidence, and Potential for Limiting Follow-Up

Association of Pathogenic/Likely Pathogenic Genetic Variants for Cardiomyopathies With Clinical Outcomes: A Multiancestry Analysis in the All of Us Research Program

BACKGROUND

This study aimed to evaluate the prevalence of pathogenic/likely pathogenic cardiomyopathy variant carriers in a multiancestry US population and examine the risk of adverse clinical outcomes.

METHODS

This retrospective cohort study included multiancestry US adults aged ≥18 years with sequencing data from the All of Us Research Program. Pathogenic/likely pathogenic variants in cardiomyopathy genes were identified using the ClinVar database. The primary outcome was heart failure. Secondary outcomes included cardiomyopathy and arrhythmia. Outcomes were identified from electronic health records. Interval-censored Cox models, taking age on the timescale, were used to assess the risk of outcomes in pathogenic/likely pathogenic variant carriers with noncarriers as the reference group.

RESULTS

Among 167 435 individuals (median age, 55.2 [39.5-66.3] years; 61.7% female; 40.7% non-European ancestry) included, the proportion of pathogenic/likely pathogenic cardiomyopathy variant carriers was 0.7% of the overall population and 0.8%, 0.8%, 0.5%, and 1.2% of European, African, East Asian, and South Asian ancestry individuals, respectively. Over the lifetime, there were 12 867 heart failure events (205 in carriers and 12 662 in noncarriers), with an incidence rate of 3.05 (95% CI, 2.66-3.49) per 1000 person-years in carriers and 1.37 (95% CI, 1.35-1.40) in noncarriers (HRadj, 2.30 [95% CI, 2.04-2.60]). Cardiomyopathy occurred in 5164 (161 in carriers and 5003 in noncarriers), with an incidence rate of 2.38 (95% CI, 2.04-2.78) per 1000 person-years among carriers and 0.54 (95% CI, 0.53-0.56) in noncarriers (HRadj, 4.31 [95% CI, 3.73-4.97]). There were 19 405 arrhythmia events (263 in carriers and 19 142 in noncarriers), with an incidence rate of 3.93 (95% CI, 3.48-4.44) per 1000 person-years among carriers and 2.09 (95% CI, 2.06-2.12) in noncarriers (HRadj, 2.12 [95% CI, 1.78-2.53]).

CONCLUSIONS

Pathogenic/likely pathogenic cardiomyopathy variant carriers have an increased risk of heart failure, cardiomyopathy, and arrhythmias. Despite the modest overall prevalence, the associated risks suggest potential benefits of targeted genetic screening for early detection and management.

Precision medicine applications in dilated cardiomyopathy: Advancing personalized care

Dilated cardiomyopathy (DCM) is a prevalent cardiac disorder affecting 1 in 250-500 individuals, characterized by ventricular dilation and impaired systolic function, leading to heart failure and increased mortality, including sudden cardiac death. DCM arises from genetic and environmental factors, such as drug-induced, inflammatory, and viral causes, resulting in diverse yet overlapping phenotypes. Advances in precision medicine are revolutionizing DCM management by leveraging genetic and molecular profiling for tailored diagnostic and therapeutic approaches. This review highlights comprehensive diagnostic evaluations, genetic discoveries, and multi-omics approaches integrating genomic, transcriptomic, proteomic, and metabolomic data to enhance understanding of DCM pathophysiology. Innovative risk stratification methods, including machine learning, are improving predictions of disease progression. Despite these advancements, the current one-size-fits-all management strategy contributes to persistently high morbidity and mortality. Emerging targeted therapies, such as CRISPR/Cas9 genome editing, aetiology-specific interventions, and pharmacogenomics, are reshaping treatment paradigms. Precision medicine holds promise for optimizing DCM diagnosis, treatment, and outcomes, aiming to reduce the burden of this debilitating condition.

Prediction and prognostic role of left ventricular systolic dysfunction in family screening for dilated cardiomyopathy and non-dilated left ventricular cardiomyopathy

AIMS

The prognostic significance of detecting left ventricular (LV) systolic dysfunction during family screening programmes (FSPs) in relatives of probands affected by dilated (DCM) and non-dilated left ventricular (NDLVC) cardiomyopathies remain unclear. This study sought to evaluate the prognostic role of LV systolic dysfunction detection in relatives of DCM/NDLVC probands and to define the most accurate FSP.

METHODS AND RESULTS

Baseline and follow-up data of first-degree relatives of probands affected by DCM/NDLVC were collected. The primary outcome was all-cause death and heart transplantation. Secondary heart failure (HF) and arrhythmic outcomes were also included. A total of 492 first degree relatives were enrolled. During a median follow-up of 110 months (interquartile range 57-188 months), only subjects that previously developed LV systolic dysfunction had primary outcomes (19 vs. 0, p < 0.001) and secondary outcomes (HF: 12 vs. 0, p = 0.005; arrhythmic: 30 vs. 0, p < 0.001). Subjects with LV systolic dysfunction detected by FSP showed lower rate of primary outcomes (FSP: n = 19 [14%]; no-FSP: n = 40 [37%]; p < 0.001) and secondary arrhythmic outcomes (FSP: n = 18 [13%]; no-FSP: n = 41 [38%]; p < 0.001). In this setting, family history of arrhythmia and being carrier of a pathogenic/likely pathogenic variant are the main risk factors for LV systolic dysfunction, while LV global longitudinal strain (LV-GLS) and Holter electrocardiogram (ECG) showed a relevant role in terms of prediction of LV systolic dysfunction and outcomes.

CONCLUSION

Relatives of DCM/NDLVC probands who developed LV systolic dysfunction during a long follow-up had a significant increased risk of major adverse cardiovascular outcomes. However, LV systolic dysfunction detected by FSP showed a better prognosis. In this context, genetics, Holter ECG and LV-GLS demonstrated their functional role for disease and event prediction.

The contribution of cardiopulmonary exercise testing in the familial screening for dilated and non-dilated left ventricular cardiomyopathies: case series

Background

The importance of family screening in relatives of patients affected by cardiomyopathies is highlighted in the international guidelines. Although electrocardiogram (ECG) and echocardiogram represent cornerstones of family screening, they may not always be sufficient to detect subtle abnormalities, especially in genotype-positive/phenotype-negative relatives. The role of cardiopulmonary exercise testing (CPET) in providing additional clinical information during family screening, remains to be fully elucidated.

Case summary

Ten asymptomatic genotype-positive/phenotype-negative first-degree relatives of probands affected by dilated cardiomyopathy (DCM) and non-dilated left ventricular cardiomyopathy (NDLVC) were evaluated in the context of family screening. Cardiopulmonary exercise testing was integrated into the initial diagnostic evaluation. Two out of 10 relatives showed an abnormal CPET, with alteration in O2 kinetic.

Discussion

Family screening in relatives of DCM and NDLVC patients, particularly in genotype-positive/phenotype-negative subjects, remains challenging due to difficulties in assessing the subtle abnormalities that may represent an initial clinical manifestation of the disease and support early treatment initiation. A more accurate and comprehensive familial screening may be achieved by integrating ECG and echocardiogram-the current first-line assessments-with data from additional tools, such as global longitudinal strain on echocardiogram, cardiac magnetic resonance, Holter ECG, and CPET.

Fenotypic expressions and clinical manifestations of arrhythmogenic cardiomyopathy

Arrhythmogenic cardiomyopathy (ACM) is a cardiac disorder characterized by structural alterations of the myocardium, which predisposes individuals to ventricular arrhythmias and increases the risk of sudden cardiac death. Initially described as arrhythmogenic right ventricular cardiomyopathy, the involvement of the left ventricle (LV) has been subsequently recognized, leading to the classification of various phenotypes under LV non-dilated cardiomyopathy. The clinical spectrum of ACM ranges from life-threatening ventricular arrhythmias to overt heart failure, sometimes presenting with acute myocarditis-like episodes and extracardiac symptoms, further contributing to the disease's heterogeneity. Diagnosis relies on imaging modalities, such as echocardiogram and cardiac magnetic resonance imaging, to detect areas of fibro-fatty replacement and/or non-ischemic ventricular scarring, integrated with genetic analysis. The 2023 European Society of Cardiology guidelines on Cardiomyopathies underscore the importance of a comprehensive diagnostic approach, combining imaging and genetics for arrhythmic risk stratification and comprehensive patient management. Growing evidence on genotype-phenotype correlation, along with the validation of specific predictive scores, is improving ACM clinical management and promoting personalized treatment tailored to individual and familial characteristics.

Pathophysiology of dilated cardiomyopathy: from mechanisms to precision medicine

Dilated cardiomyopathy (DCM) is a complex disease with multiple causes and various pathogenic mechanisms. Despite improvements in the prognosis of patients with DCM in the past decade, this condition remains a leading cause of heart failure and premature death. Conventional treatment for DCM is based on the foundational therapies for heart failure with reduced ejection fraction. However, increasingly, attention is being directed towards individualized treatments and precision medicine. The ability to confirm genetic causality is gradually being complemented by an increased understanding of genotype-phenotype correlations. Non-genetic factors also influence the onset of DCM, and growing evidence links genetic background with concomitant non-genetic triggers or precipitating factors, increasing the extreme complexity of the pathophysiology of DCM. This Review covers the spectrum of pathophysiological mechanisms in DCM, from monogenic causes to the coexistence of genetic abnormalities and triggering environmental factors (the 'two-hit' hypothesis). The roles of common genetic variants in the general population and of gene modifiers in disease onset and progression are also discussed. Finally, areas for future research are highlighted, particularly novel therapies, such as small molecules, RNA and gene therapy, and measures for the prevention of arrhythmic death.

2025 Heart Disease and Stroke Statistics: A Report of US and Global Data From the American Heart Association

BACKGROUND

The American Heart Association (AHA), in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, nutrition, sleep, and obesity) and health factors (cholesterol, blood pressure, glucose control, and metabolic syndrome) that contribute to cardiovascular health. The AHA Heart Disease and Stroke Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, brain health, complications of pregnancy, kidney disease, congenital heart disease, rhythm disorders, sudden cardiac arrest, subclinical atherosclerosis, coronary heart disease, cardiomyopathy, heart failure, valvular disease, venous thromboembolism, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The AHA, through its Epidemiology and Prevention Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States and globally to provide the most current information available in the annual Statistical Update with review of published literature through the year before writing. The 2025 AHA Statistical Update is the product of a full year's worth of effort in 2024 by dedicated volunteer clinicians and scientists, committed government professionals, and AHA staff members. This year's edition includes a continued focus on health equity across several key domains and enhanced global data that reflect improved methods and incorporation of ≈3000 new data sources since last year's Statistical Update.

RESULTS

Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Systematic Review, Meta-Analysis, and Population Study to Determine the Biologic Sex Ratio in Dilated Cardiomyopathy

BACKGROUND

Dilated cardiomyopathy (DCM) appears to be diagnosed twice as often in male than in female patients. This could be attributed to underdiagnosis in female patients or sex differences in susceptibility. Up to 30% of cases have an autosomal dominant monogenic cause, where equal sex prevalence would be expected. The aim of this systematic review, meta-analysis, and population study was to assess the sex ratio in patients with DCM, stratified by genetic status, and evaluate whether this is influenced by diagnostic bias.

METHODS

A literature search identified DCM patient cohorts with discernible sex ratios. Exclusion criteria were studies with a small (n<100), pediatric, or peripartum population. Meta-analysis and metaregression compared the proportion of female participants for an overall DCM cohort and the following subtypes: all genetic DCM, individual selected DCM genes (TTN and LMNA), and gene-elusive DCM. Population DCM sex ratios generated from diagnostic codes were also compared with those from sex-specific means using the UK Biobank imaging cohort; this established ICD coded, novel imaging-first, and genotype first determined sex ratios.

RESULTS

A total of 99 studies, with 37 525 participants, were included. The overall DCM cohort had a 0.30 female proportion (95% CI, 0.28-0.32), corresponding to a male:female ratio (M:F) of 2.38:1. This was similar to patients with an identified DCM variant (0.31 [95% CI, 0.26-0.36]; M:F 2.22:1; P=0.56). There was also no significant difference when compared with patients with gene-elusive DCM (0.30 [95% CI, 0.24-0.37]; M:F 2.29:1; P=0.81). Furthermore, the ratio within autosomal dominant gene variants was not significantly different for TTN (0.28 [95% CI, 0.22-0.36]; M:F 2.51:1; P=0.82) or LMNA (0.35 [95% CI, 0.27-0.44]; M:F 1.84:1; P=0.41). Overall, the sex ratio for DCM in people with disease attributed to autosomal dominant gene variants was similar to the all-cause group (0.34 [95% CI, 0.28-0.40]; M:F 1.98:1; P=0.19). In the UK Biobank (n=47 549), DCM defined by International Classification of Diseases, 10th revision, coding had 4.5:1 M:F. However, implementing sex-specific imaging-first and genotype-first diagnostic approaches changed this to 1.7:1 and 2.3:1, respectively.

CONCLUSIONS

This study demonstrates that DCM is twice as prevalent in male patients. This was partially mitigated by implementing sex-specific DCM diagnostic criteria. The persistent male excess in genotype-positive patients with an equally prevalent genetic risk suggests additional genetic or environmental drivers for sex-biased penetrance.

REGISTRATION

URL: https://www.crd.york.ac.uk/prospero; Unique identifier: CRD42023451944.

Yield of family screening for dilated cardiomyopathy: 10-year experience at a multidisciplinary cardiogenetic outpatient clinic

INTRODUCTION

Current family screening approaches in dilated cardiomyopathy (DCM) depend on the presence or absence of a familial genetic variant, in which variant pathogenicity (i.e. benign or pathogenic) classification drives screening recommendations. However, this approach has never been systematically evaluated.

METHODS

To describe the yield of DCM family screening stratified by variant classification in the Netherlands, we included 358 relatives (mean age ± standard deviation: 44.4 ± 15.9 years at baseline; 52% female; 41% (likely) pathogenic (LP/P) variant carriers from 210 families). Demographics, symptoms and genetic/cardiac test results were obtained. Endpoints were the development of DCM (left ventricular ejection fraction < 50% of non-ischaemic aetiology) or occurrence of major adverse cardiovascular events (MACE) (i.e. heart failure hospitalisation, ventricular arrhythmia or death). Probability of DCM or MACE was assessed with the Kaplan-Meier method.

RESULTS

DCM was present in 32 relatives (9%) (25/32 (78%) with LP/P variant) at baseline and in an additional 10/97 relatives (10%) (9/10 (90%) with LP/P variant) who were re-evaluated during a median follow-up time of 5.0 years (interquartile range: 3.2-7.4). Of the 128 relatives without the familial LP/P variant, none developed DCM. MACE was experienced by 5 relatives (1%) (4/5 (80%) with LP/P variant), all of whom had DCM at the time of the event.

CONCLUSION

The yield of DCM family screening was ~10% at baseline and another ~10% during 5‑year follow-up. Relatives without the familial LP/P variant could be safely discharged. These results reinforce the use of a genetics-first screening approach in relatives from families with an LP/P variant. This will lower the burden on resources in Dutch hospitals and help allocate resources to those who are most likely to benefit.

Family Screening in Hypertrophic Cardiomyopathy: Identification of Relatives With Low Yield From Systematic Follow-Up

BACKGROUND

Hypertrophic cardiomyopathy (HCM) is a common inherited cardiac disease, and clinical and genetic family screening is recommended by guidelines.

OBJECTIVES

This study sought to investigate the diagnostic yield of screening relatives of HCM patients and identify predictive factors for HCM development during long-term follow-up in relatives from gene-elusive families.

METHODS

This was a retrospective cohort study of families screened at clinics for inherited cardiomyopathies in Eastern Denmark, from 2006 to 2023.

RESULTS

We included 1,230 relatives (55% female; age: 42 ± 17 years) from 531 families. The combined clinical and genetic yield at baseline was 26% (n = 321). After 7 years (mean) of follow-up (6,762 person-years), 43 (4%) additional relatives developed HCM. The strongest predictors of developing HCM were carrying a likely pathogenic/pathogenic variant (HR: 4.58; 95% CI: 2.50-8.40; P < 0.001) and larger left ventricular maximum wall thickness (MWT) (HR: 2.21 per mm; 95% CI: 1.76-2.77 per mm; P < 0.001). In gene-elusive families, we found that an MWT of ≥10 mm represented the optimal classification threshold for developing HCM (area under the curve: 0.80), with only 2 (0.4%) relatives from gene-elusive families with an MWT of <10 mm developing HCM during follow-up.

CONCLUSIONS

In HCM, the diagnostic yield of a single screening visit was 1 in 4, and the additional yield during 7 years of follow-up was 4%. Gene carriers and relatives from gene-elusive families with a baseline MWT of ≥10 mm were at the highest risk of developing HCM during follow-up. These findings may inform future recommendations on the management of relatives of HCM patients.

Evaluation of the 2021 ESC recommendations for family screening in hereditary transthyretin cardiac amyloidosis

AIMS

The 2021 European Society of Cardiology (ESC) screening recommendations for individuals carrying a pathogenic transthyretin amyloidosis variant (ATTRv) are based on expert opinion. We aimed to (i) determine the penetrance of ATTRv cardiomyopathy (ATTRv-CM) at baseline; (ii) examine the value of serial evaluation; and (iii) establish the yield of first-line diagnostic tests (i.e. electrocardiogram, echocardiogram, and laboratory tests) as per 2021 ESC position statement.

METHODS AND RESULTS

We included 159 relatives (median age 55.6 [43.2-65.9] years, 52% male) at risk for ATTRv-CM from 10 centres. The primary endpoint, ATTRv-CM diagnosis, was defined as the presence of (i) cardiac tracer uptake in bone scintigraphy; or (ii) transthyretin-positive cardiac biopsy. The secondary endpoint was a composite of heart failure (New York Heart Association class ≥II) and pacemaker-requiring conduction disorders. At baseline, 40/159 (25%) relatives were diagnosed with ATTRv-CM. Of those, 20 (50%) met the secondary endpoint. Indication to screen (≤10 years prior to predicted disease onset and absence of extracardiac amyloidosis) had an excellent negative predictive value (97%). Other pre-screening predictors for ATTRv-CM were infrequently identified variants and male sex. Importantly, 13% of relatives with ATTRv-CM did not show any signs of cardiac involvement on first-line diagnostic tests. The yield of serial evaluation (n = 41 relatives; follow-up 3.1 [2.2-5.2] years) at 3-year interval was 9.4%.

CONCLUSIONS

Screening according to the 2021 ESC position statement performs well in daily clinical practice. Clinicians should adhere to repeating bone scintigraphy after 3 years, as progressing to ATTRv-CM without signs of ATTRv-CM on first-line diagnostic tests or symptoms is common.

Navigating the penetrance and phenotypic spectrum of inherited cardiomyopathies

Inherited cardiomyopathies are genetic diseases that can lead to heart failure and sudden cardiac death. These conditions tend to run in families, following an autosomal dominant pattern where first-degree relatives have a 50% chance of carrying the pathogenic variant. Despite significant advancements and increased accessibility of genetic testing, accurately predicting the phenotypic expression of these conditions remains challenging due to the inherent variability in their clinical manifestations and the incomplete penetrance observed. This poses challenges in providing patient care and effectively communicating the potential risk of future disease to patients and their families. To address these challenges, this review aims to synthesize the available evidence on penetrance, expressivity, and factors influencing disease expression to improve communication and risk assessment for patients with inherited cardiomyopathies and their family members.

2024 Heart Disease and Stroke Statistics: A Report of US and Global Data From the American Heart Association

BACKGROUND

The American Heart Association (AHA), in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, nutrition, sleep, and obesity) and health factors (cholesterol, blood pressure, glucose control, and metabolic syndrome) that contribute to cardiovascular health. The AHA Heart Disease and Stroke Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, brain health, complications of pregnancy, kidney disease, congenital heart disease, rhythm disorders, sudden cardiac arrest, subclinical atherosclerosis, coronary heart disease, cardiomyopathy, heart failure, valvular disease, venous thromboembolism, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The AHA, through its Epidemiology and Prevention Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States and globally to provide the most current information available in the annual Statistical Update with review of published literature through the year before writing. The 2024 AHA Statistical Update is the product of a full year's worth of effort in 2023 by dedicated volunteer clinicians and scientists, committed government professionals, and AHA staff members. The AHA strives to further understand and help heal health problems inflicted by structural racism, a public health crisis that can significantly damage physical and mental health and perpetuate disparities in access to health care, education, income, housing, and several other factors vital to healthy lives. This year's edition includes additional global data, as well as data on the monitoring and benefits of cardiovascular health in the population, with an enhanced focus on health equity across several key domains.

RESULTS

Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Timing of cardioverter-defibrillator implantation in patients with cardiac laminopathies-External validation of the LMNA-risk ventricular tachyarrhythmia calculator

BACKGROUND

LMNA genotype-positive patients have high risk of experiencing life-threatening ventricular tachyarrhythmias (VTAs). The LMNA-risk VTA calculator published in 2019 has not been externally validated.

OBJECTIVE

The purpose of this study was to validate the LMNA-risk VTA calculator.

METHODS

We included LMNA genotype-positive patients without previous VTAs from 2 large Scandinavian centers. Patients underwent electrocardiography, 24-hour Holter monitoring, and echocardiographic examinations at baseline and repeatedly during follow-up. Validation of the LMNA-risk VTA calculator was performed using Harrell's C-statistic derived from multivariable Cox regression analysis.

RESULTS

We included 118 patients (age 37 years [IQR 27-49 years]; 39 [33%] probands; 65 [55%] women; 100 [85%] with non-missense LMNA variants). Twenty-three patients (19%) experienced VTA during 6.1 years (interquartile range 3.0-9.1 years) follow-up, resulting in 3.0% (95% confidence interval 2.0%-4.5%) yearly incidence rate. Atrioventricular block and reduced left ventricular ejection fraction were independent predictors of VTAs, while nonsustained ventricular tachycardia, male sex, and non-missense LMNA variants were not. The LMNA-risk VTA calculator showed 83% sensitivity and 26% specificity for identifying patients with VTAs during the coming 5 years, and a Harrell's C-statistic of 0.85, when applying ≥7% predicted 5-year VTA risk as threshold. The sensitivity increased to 100% when reevaluating risk at the time of last consultation before VTA. The calculator overestimated arrhythmic risk in patients with mild and moderate phenotype, particularly in men.

CONCLUSION

Validation of the LMNA-risk VTA calculator showed high sensitivity for subsequent VTAs, but overestimated arrhythmic risk when using ≥7% predicted 5-year risk as threshold. Frequent reevaluation of risk was necessary to maintain the sensitivity of the model.

Genetic characterization of juvenile sudden cardiac arrest and death in Tuscany: The ToRSADE registry

Background

Sudden cardiac arrest (SCA) in young people represents a dramatic event, often leading to severe neurologic outcomes or sudden cardiac death (SCD), and is frequently caused by genetic heart diseases. In this study, we report the results of the Tuscany registry of sudden cardiac death (ToRSADE) registry, aimed at monitoring the incidence and investigating the genetic basis of SCA and SCD occurring in subjects < 50 years of age in Tuscany, Italy.

Methods and results

Creation of the ToRSADE registry allowed implementation of a repository for clinical, molecular and genetic data. For 22 patients, in whom a genetic substrate was documented or suspected, blood samples could be analyzed; 14 were collected at autopsy and 8 from resuscitated patients after SCA. Next generation sequencing (NGS) analysis revealed likely pathogenetic (LP) variants associated with cardiomyopathy (CM) or channelopathy in four patients (19%), while 17 (81%) carried variants of uncertain significance in relevant genes (VUS). In only one patient NGS confirmed the diagnosis obtained during autopsy: the p.(Asn480Lysfs*20) PKP2 mutation in a patient with arrhythmogenic cardiomyopathy (AC).

Conclusion

Systematic genetic screening allowed identification of LP variants in 19% of consecutive patients with SCA/SCD, including subjects carrying variants associated with hypertrophic cardiomyopathy (HCM) or AC who had SCA/SCD in the absence of structural cardiomyopathy phenotype. Genetic analysis combined with clinical information in survived patients and post-mortem evaluation represent an essential multi-disciplinary approach to manage juvenile SCD and SCA, key to providing appropriate medical and genetic assistance to families, and advancing knowledge on the basis of arrhythmogenic mechanisms in inherited cardiomyopathies and channelopathies.