Circadian variation pattern of sudden cardiac arrest occurred in Chinese community.

BACKGROUND: The circadian variation pattern of sudden cardiac arrest (SCA) occurred in Chinese community including both community healthcare centres and primary hospitals remains unknown. This study analysed the circadian variation of SCA in the Chinese community. METHODS: Data between 2018 and 2022 from the remote ECG diagnosis system of Xinhua Hospital affiliated to Shanghai Jiao Tong University School of Medicine were analysed to examine the circadian rhythm of SCA, stratified by initial shockable (ventricular tachycardia or ventricular fibrillation) versus non-shockable (asystole or pulseless electrical activity) rhythm. RESULTS: Among 10 210 cases of SCA, major cases (8736, 85.6%) were non-shockable and 1474 (14.4%) cases were shockable. The circadian rhythm of SCA was as follows: peak time was from 08:00 to 11:59 (30.1%), while deep valley was from 00:00 to 03:59 (7.5%). The proportions of events by non-shockable and shockable events were similar and both reached their peak from 08:00 to 11:59, with a percentage of 29.0% and 36.4%, respectively. Multivariable analysis showed that the relative risk of shockable compared with non-shockable arrests was lower between 00:00 and 03:59 (adjusted OR (aOR): 0.72, 95% CI: 0.54 to 0.97, p=0.028) and 04:00 to 07:59 (aOR: 0.60, 95% CI: 0.46 to 0.79, p<0.001), but higher between 08:00 and 11:59 (aOR: 1.34, 95% CI: 1.09 to 1.64, p=0.005). CONCLUSIONS: In Chinese community, there is a distinct circadian rhythm of SCA, regardless of initial rhythms. Our findings may be helpful in decision-making, in that more attention and manpower should be placed on the morning hours of first-aid and resuscitation management in Chinese community.

Prevalence and associated factors of ECG abnormality patterns indicative of cardiac channelopathies among adult general population of Tehran, Iran: a report from the Tehran Cohort Study (TeCS).

BACKGROUND: The characteristics of electrocardiogram (ECG) abnormalities related to cardiac channelopathies potentially linked to sudden cardiac death (SCD) are not widely recognized in Iran. We examined the prevalence of such ECG patterns and their related factors among adult residents of Tehran, Iran. METHODS: The clinical characteristics and 12-lead ECGs of Tehran Cohort Study participants were examined. Long QT intervals, short QT intervals, Brugada syndrome (BrS) patterns, and early repolarization (ER) were evaluated using computer-based assessment software validated by cardiologists. Logistic regression models were employed to identify the factors associated with the prevalence of different ECG patterns. RESULTS: Out of 7678 available ECGs, 7350 were included in this analysis. Long QT interval, ER pattern, BrS patterns, and short QT interval were found in 3.08%, 1.43%, 0.31%, and 0.03% of participants, respectively. The prevalence of long QT interval increased with age, opium consumption, and presence of hypertension. Younger age, lower body mass index (BMI), alcohol use and male sex were independently linked to an elevated prevalence of ER pattern. Most individuals with BrS patterns were men (95%) and had lower BMI, high- and low-density lipoprotein, and total cholesterol compared to those without the BrS pattern. At a mean follow-up of 30.2 ± 5.5 months, all-cause mortality in the group exhibiting abnormal ECG patterns (6.3%) was approximately twice as high as that in the group without such patterns (2.96%). CONCLUSION: Abnormal ECG patterns corresponding to channelopathies were relatively rare among adult residents of the Tehran population, and their prevalence was influenced by various factors. CLINICAL TRIAL NUMBER: Not applicable.

Value of preparticipation cardiovascular evaluation of master athletes by self-reported symptoms and cardiovascular risk-score.

The risk of sudden cardiac death (SCD) is increased during endurance competitive sports. Coronary artery disease (CAD) is the most common cause of SCD in master athletes ≥ 35 years old (MAs). To reduce the risk of SCD self-assessment of symptoms by questionnaire, and evaluation of cardiovascular risk-score, are recommended as pre-participation cardiovascular evaluation (PCVE). We aimed to examine whether PCVE predicts CVD in MAs with or without increased risk as measured by validated score instruments.We performed a single-site observational cohort study of healthy MAs based on findings at PCVE. They were allocated in two different groups: those MAs with reported symptoms on the questionnaire and/or with elevated cardiovascular risk score were allocated to a symptom group (SG), while MAs with no symptoms, nor raised risk score were defined as control group (CG). Thereafter, all were examined with extended examinations: resting-ECG, cardiorespiratory exercise testing and echocardiography.Total, 81 (18 women) MAs participated in the study. There were no differences at baseline between SG (n = 39) and CG (n = 42); sex (p = 0.11), age (55.0 ± 9.8 vs. 51.9 ± 11.1 years; p = 0.18), maximal oxygen uptake (49.8 ± 7.6 vs. 51.6 ± 7.0 ml/kg/min; p = 0.26), resting heart rate (61.4 ± 12.8 vs. 60.2 ± 11.0/min; p = 0.66), training hours/week (7.0 ± 3.2 vs. 7.1 ± 3.1; p = 0.88). After further examination, sixteen (20%) MAs were found with CVD: 12 in SG, 4 in CG (p = 0.024). The negative predictive value and specificity of the PCVE were 90% and 58%, respectively.Negative findings on PCVE by questionnaire and cardiovascular risk-score may be a strategy to exclude subjects from preparticipation screening, thus saving resources.

Distinct Phenotypic Groups and Related Clinical Outcomes in Patients With Hypertrophic Cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is a heterogeneous disorder with varying risks of clinical outcomes, including sudden cardiac death (SCD). We aimed to identify distinct phenotypes among patients with HCM in relation to SCD risk factors, interpret their clinical characteristics, and examine their outcomes. METHODS AND RESULTS: This retrospective study analyzed 1231 consecutive patients with HCM from 2 tertiary hospitals. We performed latent class analysis to categorize patients into phenotypic groups. Three distinct phenotypic groups were identified using latent class analysis. Group 1 (n=554) consisted of young patients with HCM with minimal SCD risk factors and favorable cardiac remodeling. Group 2 (n=114) comprised young patients with HCM and a high prevalence of SCD risk factors, whereas Group 3 (n=563) included older patients (median age, 68 years). Over a median 6.5-year follow-up, 34 SCD-related events, 131 cardiovascular events, 133 all-cause mortality events, and 70 noncardiovascular mortality events were observed. Group 2 exhibited the highest rate of SCD-related events (5-year SCD rate: Group 1 versus 2 versus 3: 0.8% versus 8.2% versus 4.0%, respectively, P<0.001), and cardiovascular events were more frequent in Groups 2 and 3 compared with Group 1. All-cause and noncardiovascular mortality were the most frequent in Group 3. A simplified decision tree was developed for the straightforward assignment of phenotypic group membership, demonstrating fair concordance. CONCLUSIONS: This study identified 3 distinct clinical phenotypes in patients with HCM, each associated with different SCD risks and outcomes. Data-driven phenotyping of patients with HCM offers effective risk stratification and may optimize patient management.

Predictors of death without prior appropriate therapy in ICD recipients: the comorbidities, frailty and functional status (COMFFORT study).

OBJECTIVE: Most patients who have an implantable cardioverter-defibrillator (ICD) implant do not receive life-prolonging therapy from it. Little research has been undertaken to determine which patients benefit the least from ICD therapy. As patients age and accumulate comorbidities, the risk of death increases and the benefit of ICDs diminishes. We sought to evaluate the impact of comorbidity, frailty, functional status on death with no prior appropriate ICD therapy. METHODS: A prospective, multicentre, observational study involving 12 English hospitals was undertaken. Patients were eligible for inclusion for the study if they were scheduled to have a de novo, upgrade to or replacement of a transvenous or subcutaneous ICD or cardiac resynchronisation therapy device and defibrillator (CRT-D). Baseline characteristics were collected. Participants were asked to complete a frailty assessment (Fried score) and a functional status questionnaire (EuroQol 5-Dimension 5-Level (EQ-5D-5L)). The Charlson Comorbidity Index was calculated. Patients were prospectively followed up for 2.5 years. The primary outcome was death with no prior appropriate therapy. RESULTS: In total, 675 patients were enrolled, mean age 65.7 (IQR 65-75) years. A total of 63 patients (9.5%) died during follow-up, 58 without receiving appropriate ICD therapy. Frailty was present in 86/675 (12.7%) and severe comorbidity in 69/675 (10.2%). Multivariate predictors of death with no appropriate therapy were identified and a risk score comprising frailty, comorbidity, increasing age, estimated glomerular filtration rate and EQ-5D-5L was developed. CONCLUSION: Comorbidities, frailty and the EQ-5D-5L score are powerful, independent predictors of death with no prior appropriate therapy in ICD/CRT-D recipients.

The Hidden Heart: Exploring Cardiac Damage Post-Stroke: A Narrative Review.

Stroke-heart syndrome (SHS), a critical yet underrecognized condition, encompasses a range of cardiac complications that arise following an ischemic stroke. This narrative review explores the pathophysiology, clinical manifestations, and implications of SHS, focusing on the complex interplay between the brain and the heart. Acute ischemic stroke (AIS) triggers autonomic dysfunction, leading to a surge in catecholamines and subsequent myocardial injury. Our review highlights the five cardinal manifestations of SHS: elevated cardiac troponin (cTn) levels, acute myocardial infarction, left ventricular dysfunction, arrhythmias, and sudden cardiac death. Despite the significant impact of these complications on patient outcomes, there is a notable absence of specific guidelines for their management. Through a comprehensive literature search, we synthesized findings from recent studies to elucidate the mechanisms underlying SHS and identified gaps in the current understanding. Our findings underscore the importance of early detection and multidisciplinary management of cardiac complications post-stroke. Future research should focus on establishing evidence-based protocols to improve clinical outcomes for stroke patients with SHS. Addressing this unmet need will enhance the care of stroke survivors and reduce mortality rates associated with cardiac complications.

Lead Management: Device Programming and Defibrillation Threshold Testing.

Implantable cardioverter-defibrillators (ICDs) reduce sudden cardiac death (SCD) and improve survival in patients with a history of life-threatening arrhythmia or sudden cardiac arrest, and in select populations at high risk of SCD due to ventricular arrhythmias. However, patients with ICDs may receive inappropriate or unnecessary shocks, which have been associated with pro-arrhythmia, psychological sequelae, poor quality of life, and increased mortality. The benefits and risks of ICD therapy are therefore directly impacted on by physician operative and programming decisions. This article aims to provide a detailed review of transvenous ICD programming as guided by clinical trials.

Obesity cardiomyopathy could contribute to sudden cardiac death: a Japanese epidemiological morphological study.

BACKGROUND: We aimed to clarify the existence and pathological features of obesity cardiomyopathy (OCM) in Japan using our series of autopsy cases. METHODS: In this retrospective autopsy study, OCM was defined as cardiac hypertrophy (≥ 400 g in men, ≥ 320 g in women) of unknown aetiology in individuals with obesity (body mass index [BMI] ≥ 25 kg/m2 according to the Japanese definition of obesity). We compared cases of OCM with those with obesity without cardiac hypertrophy (OB) and normal weight without cardiac hypertrophy (normal control). Macroscopically, heart weight and cardiac parameters, including epicardial adipose tissue, were measured. Fibrosis, cardiomyocyte diameter, and adipose tissue infiltration were analysed microscopically. RESULTS: Of the 294 cases, we identified 19 cases of OCM (6.5%) and compared them with the OB and normal control groups. Patients with OCM were slightly younger than non-OCM patients (p = 0.081). The median heart weight was significantly heavier in OCM cases than in OB cases (435 g, interquartile range [IQR] 408-515 g vs. 360 g, IQR 341-385 g). Macroscopically, OCM hearts had a "globoid" appearance with a thickened right ventricular outflow tract. Some OCM cases showed focal interstitial fibrosis in the left ventricle. Approximately half the OCM cases were diagnosed with sudden cardiac death (SCD), with significant differences. CONCLUSIONS: The prevalence of OCM may be higher than expected in Japan, and this may be a specific pathological finding. Given that approximately half the cases of OCM were due to SCD, OCM may cause SCD, emphasizing the need to recognise and diagnose OCM.

[Incidence of sudden cardiac death among diseases of the circulatory system during the COVID-19 pandemic in the Penza region]. / Chastota vnezapnoi serdechnoi smerti sredi boleznei sistemy krovoobrashcheniya v period pandemii COVID-19 v Penzenskoi oblasti.

OBJECTIVE: To study the incidence of sudden cardiac death (SCD) among overall and primary morbidity of diseases of the circulatory system (DCS) during the COVID-19 pandemic, as well as several years before it in urban and rural populations of the Penza region. MATERIAL AND METHODS: Statistical analysis of data using correlation (Pearson's coefficient), regression methods, t-test was performed to determine the significance of results. RESULTS: The higher incidence of DCS among men in urban areas has been found. COVID-19 morbidity did not cause an increase in the incidence of SCD in the rural population in comparison with primary DCS morbidity, which was strongly correlated with the prevalence of novel coronavirus infection.

Implications of Associated Atrial Fibrillation in Brugada Syndrome for Sudden Cardiac Death ‒ A Case Series Analysis.

BACKGROUND Brugada syndrome (BrS) is a cardiac arrhythmia disorder characterized by ventricular arrhythmias, which can lead to sudden cardiac death (SCD). BrS is also associated with atrial arrhythmias, particularly atrial fibrillation (AF). There is ongoing debate regarding whether treated AF can still precipitate ventricular arrhythmias in patients with BrS. This case series aims to elucidate the prognostic significance of treated AF in BrS patients who experienced SCD. CASE REPORT We report on 2 patients diagnosed with Brugada syndrome (BrS) who presented with atrial fibrillation (AF). Both patients exhibited type I Brugada electrocardiographic patterns, and echocardiographic assessments revealed normal cardiac structure and function. Thyroid function tests and electrolyte levels were within normal ranges. An electrophysiology study (EPS) performed on the first patient demonstrated the induction and termination of AF, but no inducible ventricular arrhythmia was observed. Both patients declined the ablation procedure for AF treatment, opting instead for pharmacologic rhythm control with amiodarone. During follow-up visits every 3 months, neither patient reported palpitations or syncope, and electrocardiography consistently indicated sinus rhythm. Despite this, sudden cardiac death (SCD) occurred in the first patient during the first year of follow-up and in the second patient during the second year of follow-up. CONCLUSIONS Patients with BrS who have treated AF remain at a high risk of SCD. The presence of AF in BrS patients may indicate a specific variant of the SCN5A mutation, which can heighten the risk of ventricular arrhythmias and consequent SCD.

The triglyceride-glucose index, ventricular arrhythmias and major cardiovascular events in patients at high risk of sudden cardiac death.

BACKGROUND: The association between the triglyceride-glucose (TyG) index and ventricular arrhythmias (VAs) is unclear. This study aimed to investigate the relationship between the TyG index, VAs, and major cardiovascular events in patients at high risk of sudden cardiac death (SCD). METHODS: We enrolled 1046 patients at high risk of SCD with an indication for implantable cardioverter-defibrillator (ICD) implantation at the Chinese National Center for Cardiovascular Diseases. The primary outcome was VAs, defined as sustained ventricular tachycardia and ventricular fibrillation documented by the ICD. The secondary outcomes were cardiac mortality, heart transplantation, and rehospitalization for heart failure. RESULTS: The mean (± SD) age was 59.6 ± 14.0 years old, and 25.7% were female. During the mean follow-up of 36.1 months, 342 (32.7%) patients had VAs, and 185 (17.7%) patients had major cardiovascular events. The mean fasting glucose and triglyceride levels were 111.9 ± 42.7 mg/dL and 140.0 ± 95.4 mg/L, respectively, with a TyG index range of 6.96-11.8. In the Fine-Gray subdistribution hazard model analysis, an increase in the TyG index was associated with a significant increase in the VAs (per 1 TyG index, hazard ratio [HR] 2.95; 95% confidence interval [CI], 2.29-3.80) and secondary outcome (HR 2.84; 95% CI 1.86-4.34). When stratified into tertiles, the risk of VAs was significantly higher in the highest tertile (HR 4.08; 95% CI, 2.81-5.92) than in the lowest tertile. Analysis of the secondary outcome revealed similar findings (HR 3.18; 95% CI, 1.73-5.85). CONCLUSIONS: In our cohort, the pre-operational TyG index is significantly associated with VAs and major cardiovascular events for patients with high risk of SCD.

Morphological phenotype of right ventricular outflow tract is associated with cardiovascular outcomes and premature death.

Morphology of right ventricular outflow tract (RVOT) is potentially related to cardiovascular outcomes. However, this relationship still remains to be verified with direct evidence. We retrospectively reviewed cases from the autopsy specimen library in the Center of Forensic Medicine in Sun Yat-sen University from 2017 to 2023. Six RVOT morphological characteristics were measured and their association with cardiovascular diseases (CVDs), sudden cardiac death (SCD) and age at death was evaluated. Relationship between myocardial fibrosis in RVOT and CVDs was investigated. RVOT characteristics were recruited by machine learning algorithms for diagnosing CVDs. A total of 2370 cases were finally recruited. Perimeter of sub-valve plane (pSBV) in RVOT was positively associated with risk of CVDs and SCD (OR: 1.21, 95%CI: 1.07-1.37, p = 0.003; OR: 1.33, 95%CI: 1.16-1.52, p < 0.001). Compared with thickness of septum (tS) < 3.0 mm, tS ≥ 3.0 mm was associated with premature death in disease-dominant death (ß=-0.16, 95%CI: -0.20 to -0.11, p < 0.001) and SCD (ß=-0.15, 95%CI: -0.21 to -0.10, p < 0.001). Degree of myocardial fibrosis in the posterior septum was increased in coronary atherosclerosis (6.86%±2.48% vs. 4.91%±2.14%, p = 0.011) and cardiomyopathies (8.11%±3.24% vs. 4.88%±3.11%, p = 0.005). A logistic regression model, recruiting age, left and right ventricular wall thickness, pSBV, circumference of pulmonary annulus and aortic annulus, was elected as an optimal diagnostic model of CVDs, yielding AUC of 0.734 (95%CI: 0.705-0.763), 0.781 (0.740-0.821) and 0.763 (0.725-0.800) in training, validation and test sets. Increased pSBV significantly correlates with higher risk of CVDs and SCD. And tS ≥ 3.0 mm is an independent risk factor of premature death regardless of diseases.

Sudden Cardiac Death and Channelopathies: What Lies behind the Clinical Significance of Rare Splice-Site Alterations in the Genes Involved?

Background and objectives: Sudden cardiac death (SCD) is a natural and unexpected death of cardiac origin that occurs within 1 h from the onset of acute symptoms. The major leading causes of SCD are cardiomyopathies and channelopathies. In this review, we focus on channelopathies, inherited diseases caused by mutations affecting genes encoding membrane ion channels (sodium, potassium or calcium channels) or cellular structures that affect Ca2+ availability. The diagnosis of diseases such as long QT, Brugada syndrome, short QT and catecholaminergic polymorphic ventricular tachycardia (CPVT) is still challenging. Currently, genetic testing and next-generation sequencing allow us to identify many rare alterations. However, some non-coding variants, e.g., splice-site variants, are usually difficult to interpret and to classify. Methods: In our review, we searched for splice-site variants of genes involved in channelopathies, focusing on variants of unknown significance (VUSs) registered on ClinVar up to now. Results: The research led to a high number of splice-site VUSs of genes involved in channelopathies, suggesting the performance of deeper studies. Conclusions: In order to interpret the correlation between variants and pathologies, we discuss experimental studies, such as RNA sequencing and functional analysis of proteins. Unfortunately, as these in vitro analyses cannot always be performed, we draw attention to in silico studies as future perspectives in genetics. This review has the aim of discussing the potential methods of detection and interpretation of VUSs, bringing out the need for a future reclassification of variants with currently unknown significance.

Magnetocardiography in the Evaluation of Sudden Cardiac Death Risk: A Systematic Review.

Sudden cardiac death (SCD) is responsible for 15%-20% of deaths globally/year, predominantly due to ventricular arrhythmias (VA) caused by vulnerable cardiac substrate. Identifying those at risk has proved difficult with several limitations of current methods. We evaluated the evidence for magnetocardiography (MCG) in predicting SCD events. We searched Embase/Medline databases for English language papers evaluating MCG in patients at risk of VA. A total of 119 papers were screened with 27 papers included for analysis (23 case-controlled, four cohort studies); study sizes varied (n = 12 to 158). Etiology was ischemic cardiomyopathy (ICM) in 22, dilated cardiomyopathy in 2, arrhythmogenic cardiomyopathy in 1 and mixed in 2. In patients with ICM there were consistent discriminatory features seen using time-based and signal-complexity measures that persisted when evaluating the independence of these parameters. Current flow analysis demonstrated promising discriminatory results in other etiologies. The features studied support the role of MCG in identifying substrate for VA, particularly in ICM.

Do relationships between ambient temperature and serious adverse health outcomes vary among users of different antidiabetes drugs? A retrospective cohort study of US Medicaid beneficiaries with type 2 diabetes.

OBJECTIVE: Prior studies demonstrate that some untoward clinical outcomes vary by outdoor temperature. This is true of some endpoints common among persons with diabetes, a population vulnerable to climate change-associated health risks. Yet, prior work has been agnostic to the antidiabetes drugs taken by such persons. We examined whether relationships between ambient temperature and adverse health outcomes among persons with type 2 diabetes (T2D) varied by exposure to different antidiabetes drugs. DESIGN: Retrospective cohort. SETTING: Healthcare and meteorological data from five US states, 1999-2010. PARTICIPANTS: US Medicaid beneficiaries with T2D categorised by use of antidiabetes drugs. EXPOSURE: Maximum daily ambient temperature (t-max). OUTCOMES: Hospital presentation for serious hypoglycaemia, diabetic ketoacidosis (DKA) or sudden cardiac arrest (examined separately). METHODS: We linked US Medicaid to US Department of Commerce data that permitted us to follow individuals longitudinally and examine health plan enrolment, healthcare claims, and meteorological exposures-all at the person-day level. We mapped daily temperature from weather stations to Zone Improvement Plan (ZIP) codes, then assigned a t-max to each person-day based on the residential ZIP code. Among prespecified subcohorts of users of different pharmacologic classes of antidiabetes drugs, we calculated age and sex-adjusted occurrence rates for each outcome by t-max stratum. We used modified Poisson regression to assess relationships between linear and quadratic t-max terms and each outcome. We examined effect modification between t-max and a covariable for current exposure to a specific antidiabetes drug and assessed significance via Wald tests. RESULTS: We identified ∼3 million persons with T2D among whom 713 464 used sulfonylureas (SUs), dipeptidyl peptidase-4 inhibitors (DPP-4is), meglitinides, or glucagon-like peptide 1 receptor agonists (GLP1RAs). We identified a positive linear association between t-max and serious hypoglycaemia among non-insulin users of glimepiride and of glyburide but not glipizide (Wald p value for interaction among SUs=0.048). We identified an inverse linear association between t-max and DKA among users of the DPP-4i sitagliptin (p=0.016) but not the GLP1RA exenatide (p=0.080). We did not identify associations between t-max and sudden cardiac arrest among users of SUs, meglitinides, exenatide, or DPP-4is. CONCLUSIONS: We identified some antidiabetes drug class-specific and agent-specific differences in the relationship between ambient temperature and untoward glycaemic but not arrhythmogenic, safety outcomes.

Return to professional football after ICD implantation in athlete with apical hypertrophic cardiomyopathy.

The risk of sports participation in elite athletes with cardiac disease with an indication for implantable cardioverter-defibrillator (ICD) therapy is largely unknown. Currently, international guidelines provide restrictive sports advice for such athletes. This case report presents a professional football player who after an episode of syncope and diagnosis of apical hypertrophic cardiomyopathy expressed a strong wish to explore the feasibility of returning to elite-level sports. After a shared decision-making and monitored stepwise graduated rehabilitation, the athlete made a full return to professional football. Our case indicates that individualised sports advice in elite athletes with cardiac disease and an ICD may be warranted.

Cardiac channelopathies in pediatrics: a genetic update.

Cardiac channelopathies are a group of inherited syndromes that can cause malignant arrhythmias and sudden cardiac death, particularly in the pediatric population. Today, a 12-lead electrocardiogram is the most effective tool to diagnose these diseases. Incomplete penetrance and variable expressivity are hallmarks of these syndromes. Some of these malignant entities may remain hidden and only a trigger such as exercise, emotions or fever can unmask the electrical pattern to diagnose the disease. Sudden cardiac death may be the first manifestation of any of these syndromes. The use of complementary tests that allow early diagnosis is strongly recommended, among which we find: pharmacological provocations, exercise tests, and genetic analysis. Genetic testing makes it possible to unravel the origin of the disease, and also identify family members who carry the harmful genetic defect and are therefore at risk. One of the main challenges in this area is the large number of genetic variants of uncertain significance, which prevent effective translation into clinical practice. Early identification of the pediatric population at risk and adequate risk stratification are crucial to adopting personalized preventive measures that reduce the risk of lethal episodes in this population. What is Known: • In the pediatric population, malignant arrhythmias leading to sudden cardiac death are mainly caused by inherited syndromes. • A conclusive genetic diagnosis unravels the origin of the syndrome and allows cascade screening to identify relatives carrying the genetic alteration. What is New: • The use of sequencing technologies allows a broad genetic analysis, helping to unravel new genetic alterations causing inherited arrhythmogenic syndromes. • A periodic reanalysis of genetic variants that currently have an ambiguous role will help discern those that are truly pathogenic.

[Race against sudden death : the benefits of pre-participation cardiovascular screening]. / Course contre la mort subite : intérêt du dépistage cardiovasculaire avant une compétition sportive.

Sudden death (SD) in young, apparently healthy athletes under 35 is an underestimated public health problem in Belgium. This is dramatically illustrated by the case of a 28-year old ultra-trail runner who suffered cardiac arrest during training, revealing an unrecognized cardiomyopathy. This highlights the importance of pre-participation cardiovascular screening in identifying such hidden conditions. The variety of causes of SD, mainly of cardiac origin, underlines the complexity of screening and the need to tailor it to the specific risks of each individual. The central issue in screening is the relevance of the resting 12-lead electrocardiogram (ECG). While some countries have adopted it with positive results, others continue to debate its systematic inclusion. Sudden death affects not only professional athletes, but also amateurs, who are often less medically monitored. The aim of cardiovascular screening is twofold: to identify young people at risk, while not unnecessarily limiting access to sport for those with no cardiac pathology. The effectiveness of the ECG is well recognized, but the implementation of such systematic screening in Belgium must take into account certain practical aspects.

La mort subite (MS) chez les jeunes sportifs de moins de 35 ans, en bonne santé apparente, est une problématique de santé publique sous-estimée en Belgique. Cette réalité est dramatiquement illustrée par le cas d'un ultra-traileur de 28 ans, victime d'un arrêt cardiaque lors d'un entraînement, révélant une cardiomyopathie méconnue. Cela met en lumière l'importance d'un dépistage cardiovasculaire pré-participatif pour identifier de telles affections cachées. La variété des causes de MS, principalement d'origine cardiaque, souligne la complexité du dépistage et la nécessité de l'adapter en fonction des risques spécifiques à chaque individu. La question centrale du dépistage est la pertinence de l'électrocardiogramme (ECG) à 12 dérivations de repos. Tandis que certains pays l'ont adopté avec des résultats positifs, d'autres continuent de débattre sur son inclusion systématique. La MS n'affecte pas que les athlètes professionnels, mais aussi les amateurs, souvent moins suivis sur le plan médical. L'objectif du dépistage cardiovasculaire est double : identifier les jeunes à risque, tout en ne limitant pas inutilement l'accès au sport pour ceux dépourvus de pathologie cardiaque. L'efficacité de l'ECG est reconnue, mais la mise en œuvre d'un tel dépistage systématique en Belgique doit tenir compte de certains aspects pratiques.

Arrhythmic Risk Stratification by Cardiovascular Magnetic Resonance Imaging in Patients With Nonischemic Cardiomyopathy.

BACKGROUND: Myocardial fibrosis (MF) forms part of the arrhythmic substrate for ventricular arrhythmias (VAs). OBJECTIVES: This study sought to determine whether total myocardial fibrosis (TF) and gray zone fibrosis (GZF), assessed using cardiovascular magnetic resonance, are better than left ventricular ejection fraction (LVEF) in predicting ventricular arrhythmias in patients with nonischemic cardiomyopathy (NICM). METHODS: Patients with NICM in a derivation cohort (n = 866) and a validation cohort (n = 848) underwent quantification of TF and GZF. The primary composite endpoint was sudden cardiac death or VAs (ventricular fibrillation or ventricular tachycardia). RESULTS: The primary endpoint was met by 52 of 866 (6.0%) patients in the derivation cohort (median follow-up: 7.5 years; Q1-Q3: 5.2-9.3 years). In competing-risks analyses, MF on visual assessment (MFVA) predicted the primary endpoint (HR: 5.83; 95% CI: 3.15-10.8). Quantified MF measures permitted categorization into 3 risk groups: a TF of >0 g and ≤10 g was associated with an intermediate risk (HR: 4.03; 95% CI: 1.99-8.16), and a TF of >10 g was associated with the highest risk (HR: 9.17; 95% CI: 4.64-18.1) compared to patients with no MFVA (lowest risk). Similar trends were observed in the validation cohort. Categorization into these 3 risk groups was achievable using TF or GZF in combination or in isolation. In contrast, LVEF of <35% was a poor predictor of the primary endpoint (validation cohort HR: 1.99; 95% CI: 0.99-4.01). CONCLUSIONS: MFVA is a strong predictor of sudden cardiac death and VAs in NICM. TF and GZF mass added incremental value to MFVA. In contrast, LVEF was a poor discriminator of arrhythmic risk.