The 2023 European Task Force Criteria for Diagnosis of Arrhythmogenic Cardiomyopathy: Historical Background and Review of Main Changes.

Arrhythmogenic cardiomyopathy (ACM) is a cardiac disease featured by non-ischemic myocardial scarring linked to ventricular electrical instability. As there is no single gold-standard test, diagnosing ACM remains challenging and a combination of specific criteria is needed. The diagnostic criteria were first defined and widespread in 1994 and then revised in 2010, approaching and focusing primarily on right ventricular involvement without considering any kind of left ventricular variant or phenotype. Years later, in 2020, with the purpose of overcoming previous limitations, the Padua Criteria were introduced by an international expert report. The main novel elements were the introduction of specific criteria for left ventricular variants as well as the use of cardiac magnetic resonance for tissue characterization and scar detection. The last modifications and refinement of these criteria were published at the end of 2023 as the European Task Force criteria, by a "head-quarter" of ACM international experts, proving the emerging relevance of this condition besides its difficult diagnosis. In this review, emphasizing the progress in understanding the aetiology of the cardiomyopathy, an analysis of the new criteria is presented. The introduction of the term "scarring/arrhythmogenic cardiomyopathy" sets an important milestone in this field, underlying how non-ischemic myocardial scarring-typical of ACM-and arrhythmic susceptibility could be the main pillars of numerous different phenotypic variants regardless of etiology.

Heart transplantation for pediatric patients with malignant arrhythmias: Indications and Outcomes.

BACKGROUND: Arrhythmias can lead to cardiac arrest (CA) and heart failure. When intractable, heart transplant (HTX) can become the only viable treatment. This rare, high-risk cohort has not been reported as a distinct group. OBJECTIVE: Characterize the outcomes of pediatric patients listed for HTX with the primary indication being malignant arrhythmia (MA). METHODS: Using the Pediatric Heart Transplant Society prospective registry, we identified all patients <18 years-old listed between 2014-2022. MA as the listing indication was categorized into primary tachy-arrhythmia (PT), inherited arrhythmia (IA), congenital heart disease (CHD) and cardiomyopathy (CM) with secondary arrhythmia. Demographic, listing and transplant data were analyzed. RESULTS: Among 4630 patients listed and 3317 transplanted, MA was the indication in 63 (1.4%) and 49 (1.5%), respectively. MA patients were categorized as PT in 11, IA in 4, CHD in 6 and CM in 42. When compared to the non-MA cohort, patients listed for MA were older (mean (SD) age 10.6 (6.2) vs. 6.1 (6.2) years, p<0.01), more likely to present with a CA (43% vs. 11%, p<0.01), and less likely to be in the intensive care unit (40% vs. 58%, p<0.01) or on inotropes (30% vs. 60%, p<0.01) at listing. Outcomes including waitlist mortality, transplantation, post-transplant survival and freedom from rejection were comparable to the non-MA cohort. CONCLUSION: Patients with MA constitute a small proportion of those listed for HTX in childhood. CM was the most common category, while IA and PT were rare. Their waitlist mortality and post-transplant outcomes were comparable to the non-MA cohort.

CTG repeat length underlying cardiac events and sudden death in myotonic dystrophy type 1.

Aims: Myotonic dystrophy Type 1 (DM1) is caused by the expansion of CTG repeats (CTGn) in the DM1 protein kinase (DMPK) gene, while it remains unclear whether CTGn may be associated with the incidence of cardiac events or sudden death in Japan as well as Europe. The aim of this study was to investigate the association between CTGn and cardiac involvements. Methods and results: This cohort study included patients with DM1 who were retrospectively recruited from nine Japanese hospitals specializing in neuromuscular diseases. A total of 496 patients with DM1 who underwent a genetic test in the DMPK gene were analysed. Patients with congenital form or under 15 years old were excluded and patients were assigned into the quartiles. When we compared the incidence of cardiac events including advanced/complete atrioventricular block, pacemaker implantation, and ventricular tachycardias or mortality among four groups, patients with 1300 or longer CTGn experienced composite cardiac events [hazard ratio (HR): 3.19, 95% confidence interval (CI): 1.02-9.99, P = 0.014] more frequently and had significantly higher mortality rate (HR: 6.79, 95% CI: 2.05-22.49, P < 0.001) than those under 400 CTGn while the rate of sudden death was not significantly different. Conclusion: Regarding the cardiac events and mortality in patients with DM1, patients with 1300 or longer CTGn are at especially high risk.

Unusual Recurrent Multivessel Coronary Artery Spasm: A Case Report and Literature Review.

Coronary artery spasms (CAS) can manifest in various forms, from silent ischemia to severe cardiac events like myocardial infarction and sudden death. This case involves a 56-year-old male with recurrent ischemic chest pain and varying ECG signs. Cardiac catheterization revealed multiple coronary spasms that resolved spontaneously or with intracoronary nitroglycerin. The report emphasizes the severe presentations of multiple CAS and the importance of thorough diagnostic evaluation to avoid unnecessary interventions, highlighting the diagnostic challenges in managing such cases.

Circadian (Diurnal/Nocturnal) Pattern of Cardiac Arrhythmias.

Circadian rhythms follow 24-hour biological-cycle patterns controlled by internal biological or circadian clocks that optimize organismal homeostasis according to predictable environmental changes. These clocks are found in virtually all cells in the body, including cardiomyocytes. Triggers for and/or the occurrence of sudden cardiac death (SCD), and cardiac arrhythmias seem to follow such daily patterns. This review highlights data from studies exploring the role of day/night rhythms in the timing of arrhythmic events, studies describing the enviromental, behavioral and circadian mechanisms regulating cardiac electrophysiology focusing on the circadian pattern of arrhythmias and SCD. Mechanisms involved relate to circadian control of electrophysiological properties, vagal tone, and sleep disorders, as well as the potential interaction and synergism among these factors. By studying the diurnal variations of arrhythmias, therapy can be improved by optimally timing it to their circadian pattern and a person's internal body clock-time. Potential treatment targets for arrhythmias with nocturnal onset may include upstream therapy for underlying comorbidities, type and timing of drug intake, pulmonary vein isolation, ablation of the ganglionated plexus, and autonomic nervous system control. Thus, specific history taking, screening and diagnostic workup are recommended to identify and characterize comorbidities and potential contributors to nocturnal arrhythmias, such as obesity, advanced age, diabetes, hypertension and heart failure. In this direction, symptoms of sleep apnea may comprise snoring and excessive daytime sleepiness. Risk factors include obesity, decreased upper airway dimensions, and heart failure. Thus, one should have a low threshold for sleep testing to assess for sleep apnea. Sleep apnea treatment decreases ventricular arrhythmias and ameliorates some severe bradycardic episodes often obviating the need for pacemaker implantation. Importantly, comorbidity treatment and lifestyle optimization remain crucial.

Excess of high-caffeinated energy drinks causing ventricular arrhythmias.

A young male patient had palpitations after consumption of few high caffeinated energy drinks which he took after his office hours to relieve fatigue. He immediately seeked medical help. Electrocardiogram showed multiple runs of non-sustained ventricular tachycardia and ventricular bigeminy and trigeminy. Echocardiography was normal. The patient was admitted to intensive care unit and treated with anti-arrhythmic drugs to which the arrhythmias responded and subsided. Cardiac magnetic resonance imaging of heart did not reveal any structural heart abnormality and treadmill stress test was negative ruling out significant coronary artery disease. High caffeinated energy drinks can produce serious ventricular arrhythmias if taken beyond safe doses. These ventricular arrhythmias are known to be causative factor for sudden cardiac arrest and therefore a caution & regulation is needed in widespread unrestricted used of these drinks.

A 10-year retrospective analysis of sudden unexpected death in the young investigated at Salt River Mortuary, Cape Town.

Sudden unexpected death in the young (SUDY) is defined as the rapid, unsuspected demise of an apparently healthy individual between the ages of one and 40 years. There is a gap in research pertaining to this population in a South African context. This retrospective study aimed to explore the burden, scope of post-mortem investigation, and risk factors of SUDY admissions to Salt River Mortuary (SRM) in Cape Town between 1 January 2010 and 31 December 2019. Medico-legal case files pertaining to SUDY cases from SRM were reviewed. SRM received a total of 34 601 admissions in the 10-year period; of which 1 997 (5.77%) were SUDY cases. Nearly two-thirds (62.59%) of the SUDY admissions were male. The leading cause of death was pneumonia (17.11%), and the most prevalent organ system implicated in cause of death was the pulmonary system (45.19%). At least 32.46% of SUDY cases were infectious-related, with varying degrees of confidence. A large proportion of cases had no history of acute or chronic illness (45.43%), and no family history of illness (56.66%). In total, 52 potential candidates were identified for a molecular autopsy, of which 47 have stored biological samples for future investigations. This study advocates for the routine performance of post-mortem ancillary microbiological and toxicological testing in cases of SUD, considering the large burden of infectious disease and substance abuse in South Africa. The retention of biological samples in undetermined or non-specific natural cases is also urged, to allow for cause of death determination on a molecular level.

Sudden death due to enterotoxemia among Arabian camels (Camelus dromedaries) and associated risk factors.

Background: Sudden death is defined as an unexpected death occurring with no observed antecedent clinical signs. Aim: The current study was performed to notice the tangible causes of sudden death among 51 out of 340 she-camels on a private farm in the eastern region of El Khafgi, Saudi Arabia. Methods: A retrospective cohort study design was conducted to investigate the sudden death of camels through microscopic examination of fecal matter to identify the gastrointestinal parasites, analysis of whole blood thin films to diagnose blood parasites, blood culturing to recognize bacterial infection as Pasteurella multicida, and macroscopic postmortem examination to identify the gastrointestinal adult worm. The quantity and composition of feed were also analyzed. Afterward, a commercial multiscreen Ag-ELISA kit technique determined the toxins of Clostridium perfringens (C. perfringens). Results: The results revealed that the incidence rate of sudden death was 15%. The sudden death occurred due to C. perfringens enterotoxins detected in the rumen, intestinal content, and intestinal wall. The enterotoxins and Alpha toxins were noticed, but the other toxin types, including Beta and Epsilon, could not be detected. All C. perfringens toxins were discovered to be negative in fecal matter. A significant association was reported between sudden death, she-camels age, and feeding habits as risk factors (p = 0.020 and 0.028, respectively). Risk factor assessment by relative risk (RR) revealed that the odds of RR of sudden death occurring among she-camels aged over two years were higher than those less than two years (2.24 CI 95%, 1.093-4.591). Furthermore, the odds RR of sudden death occurring due to exposure of she-camels to a concentrated ration of 18% were higher twice than those not exposed (2.346 CI 95%, 1.039-5.296). Conclusion: Clostridium perfringens enterotoxaemia should be listed as a cause of sudden death in camels and the alteration in diet with 18% concentration feed changes the intestinal environment, which leads to C. perfringens proliferating and yielding potent toxins. More observations and interferences like regular immunization are recommended to reduce the disease and increase the awareness of the farmers of the importance of risk factors.

Children With Airway Compressions Caused by Mediastinal Tumors: A Single-Center Case Series.

BACKGROUND: Mediastinal tumors in children may be misdiagnosed as bronchial asthma, resulting in delayed diagnosis and airway obstruction leading to cardiac arrest. PURPOSE: This study aimed to identify factors for early diagnosis of mediastinal tumors in children to avoid a life-threatening situation. METHODS: We retrospectively reviewed the medical records of 14 children with airway compressions caused by mediastinal tumors who visited the Hyogo Prefectural Kobe Children's Hospital between April 2016 and September 2023. RESULTS: The median age at diagnosis was 9.8 years; all patients had anterior mediastinal tumors. Respiratory symptoms included cough in seven cases, orthopnea in five cases, wheezing in four cases, tachypnea in one case, and no symptoms in one case. Although six patients (42%) visited medical institutions presenting with respiratory symptoms, more than a month passed before diagnosis. Six patients (42%) received bronchial asthma treatment. Most cases (n=9, 64%) were diagnosed using chest radiography; two cases were diagnosed using computed tomography. Three patients experienced cardiac arrest because of airway obstruction before mediastinal tumor diagnosis. Chest radiography on admission showed abnormal mediastinal shadows in all cases. CONCLUSION: In children with prolonged respiratory symptoms and an atypical course of bronchial asthma, mediastinal tumors should be considered as a differential diagnosis, and chest radiography should be performed.

Prevalence of cardiomyopathy and cardiac mortality in a colony of non-purebred cats in New Zealand.

AIMS: To evaluate the prevalence of subclinical cardiomyopathy and cardiac mortality in a research colony of non-purebred cats, established as a model of the wider cat population in New Zealand. METHODS: All apparently healthy, compliant, non-pregnant, non-neonatal cats in the colony at the Centre for Feline Nutrition (Massey University, Palmerston North, NZ) underwent physical examination and echocardiography using a 4.4-6.2-MHz probe by a board-certified veterinary cardiologist. Cardiac phenotype was classified following current guidelines. Hypertrophic cardiomyopathy (HCM) phenotype was defined as an end-diastolic left ventricular wall thickness ≥ 6 mm. Colony mortality data from February 2012 to February 2022 was reviewed to determine cardiac mortality. RESULTS: Cats (n = 132; 65 females and 67 males) included in the study had a median age of 4.1 (IQR 3.0-8.0) years. Thirty-two (24%) cats had a heart murmur, and three (2%) cats had an arrhythmia. Echocardiography revealed heart disease in 24 (18.2%) cats, including 23 with an HCM phenotype and one with a restrictive cardiomyopathy phenotype. Of the cats with the HCM phenotype, 3/23 had systemic hypertension or hyperthyroidism or both, and these cats were excluded from the final diagnosis of HCM (20/132; 15.2 (95% CI = 9.5-22.4)%).Between 2012 and 2022, 168 colony cats died, with 132 undergoing post-mortem examination. Heart disease was considered the cause of death in 7/132 (5.3%; 95% CI = 2.2-10.6%) cats; five had HCM, one a congenital heart defect, and one myocarditis. The overall prevalence of death related to HCM in the colony during this period was 3.8% (95% CI = 1.2-8.6%). Three cats with HCM and the cat with a congenital heart defect died unexpectedly without prior clinical signs, while congestive heart failure was observed prior to death in two cats with HCM and the cat with myocarditis. Additionally, 30/132 (22.7%) cats had cardiac abnormalities but died for non-cardiac reasons. CONCLUSIONS: Subclinical cardiomyopathy, specifically HCM, was common in cats in the colony. Given that the colony originated as a convenience selection of non-purebred cats in New Zealand, the true prevalence of HCM in the wider New Zealand population is likely to fall within the 95% CI (9.5-22%). The proportion of deaths of colony cats due to HCM was lower (3.8%) supporting the conclusion that subclinical cardiomyopathy may not progress to clinical disease causing death. CLINICAL RELEVANCE: Veterinarians should be aware of the high prevalence of subclinical HCM when treating cats. ABBREVIATIONS: CAM: Systolic anterior motion of the chordae tendineae; CFN: Centre for Feline Nutrition; HCM: Hypertrophic cardiomyopathy; LA/Ao: Left atrial to aortic ratio; LV FS: Left ventricular fractional shortening; LVIDd: Left ventricular internal diameters in end-diastole; LVIDs: Left ventricular internal diameter in end-systole; LVWT: Max Maximum left ventricular wall thickness; SAM: Systolic anterior motion of the mitral valve; 2D: Two-dimensional.

[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.

Clinical Care for Cardiovascular Disease in Patients With Williams-Beuren Syndrome.

Williams-Beuren syndrome (WBS) is a congenital multisystem disorder affecting the cardiovascular, central nervous, and musculoskeletal systems. Cardiovascular abnormalities, which consist principally of vascular stenoses, occur in approximately 80% of people with WBS and are the predominant cause of early morbidity and mortality. Supravalvar aortic stenosis and peripheral pulmonary artery stenosis are the most common stenotic lesions in WBS, though other stenoses often occur, including stenoses of the coronary arteries. Approximately one-third of people with WBS undergo cardiovascular interventions. The risk of sudden cardiac death is markedly higher than the general population, with most events occurring in the periprocedural period. Because of the rarity of WBS and the often-complex nature of the cardiovascular abnormalities, most physicians, including cardiologists, have limited experience in caring for patients with WBS. Further, heretofore, clinical cardiovascular management guidelines based on international expert consensus have not been available. This state-of-the-art review provides a comprehensive synopsis of the cardiovascular abnormalities in WBS and presents clinical management guidelines based on the authors' expert consensus.

Contemporary diagnostic approach to arrhythmogenic cardiomyopathy: The three-step work-up.

Arrhythmogenic Cardiomyopathy (ACM) is a cardiac disorder characterized by non-ischemic myocardial scarring, which may lead to ventricular electrical instability and systolic dysfunction. Diagnosing ACM is challenging as there is no single gold-standard test and a combination of criteria is required. The first diagnostic criteria were established in 1994 and revised in 2010, focusing primarily on right ventricular involvement. However, in 2019, an international expert report identified limitations of previous diagnostic scoring and developed the 2020 Padua criteria with also included criteria for diagnosis of left ventricular variants and introduced cardiac magnetic resonance tissue characterization findings for detection of left ventricular myocardial scar. These criteria were further refined and published in 2023 as the European Task Force criteria, gaining international recognition. This review provides an overview of the 20 years of progresses on the disease diagnostic from the original 1994 criteria to the most recent 2023 European criteria, highlighting the evolution into our understanding of the pathobiology and morpho-functional features of the disease.

A systematic review on the use of C-reactive protein in autopsy practice.

Postmortem analysis of C-reactive protein (CRP) in autopsies has been extensively researched for its potential utility. This analysis could aid forensic pathologists in screening for and investigating the potential infectious or inflammatory causes of death, thereby guiding appropriate autopsy procedures. To assess the diagnostic accuracy of postmortem CRP analysis in autopsy settings, a thorough electronic literature search was conducted across databases such as PubMed, Scopus, Web of Science, and Cochrane Library. Two independent reviewers screened eligible studies, followed by a methodological quality assessment using the QUADAS-2 checklist. Utilising a random-effects model, hierarchical summary receiver operating characteristic (HSROC) curve analysis and bivariate model meta-analysis were performed to evaluate heterogeneity across studies. Of the 1286 studies initially identified, nine met the eligibility criteria for the final analysis. The pooled sensitivity of postmortem CRP analysis was 0.93 (95% CI, 0.76, 0.98), with a pooled specificity of 0.80 (95% CI, 0.71, 0.87). The prevalence across studies ranged from 0.23 to 0.68, with a median of 0.5. Moderate variability was observed in the heterogeneity assessment across the primary studies. In summary, the study findings indicate that postmortem serum CRP analysis demonstrates high diagnostic accuracy with moderate heterogeneity. Additionally, postmortem CRP testing may be useful as a screening tool in autopsy practice to rule out the likelihood of sepsis.

Towards user-centered design of medical devices for SUDEP prediction and prevention: Insights from persons with epilepsy and caregivers.

OBJECTIVES: As epilepsy management medical devices emerge as potential technological solutions for prediction and prevention of sudden death in epilepsy (SUDEP), there is a gap in understanding the features and priorities that should be included in the design of these devices. This study aims to bridge the gap between current technology and emerging needs by leveraging insights from persons with epilepsy (PWE) and caregivers (CG) on current epilepsy management devices and understanding how SUDEP awareness influences preferences and design considerations for potential future solutions. METHODS: Two cross-sectional surveys were designed to survey PWE and CG on medical device design features, SUDEP awareness, and participation in medical device research. Data analysis included both qualitative thematic analysis and quantitative statistical analysis. RESULTS: The survey revealed that among 284 responses, CG were more aware of SUDEP than PWE. Comfort was identified as the primary concern regarding wearable medical devices for epilepsy management with significant differences between PWE and CG regarding acceptance and continuous use preferences. The thematic analysis identified integration with daily life, aesthetic and emotional resonance, adaptability to seizure characteristics, and user-centric design specifications as crucial factors to be considered for enhanced medical device adoption. The integration of a companion app is seen as an important tool to enhance communication and data sharing. DISCUSSION: This study reveals that while SUDEP awareness can promote the development of future SUDEP predictive and preventive medical devices, these should be designed to mitigate its impact on daily life and anxiety of both PWE and CG. Comfort and acceptance are seen as key priorities to support continuous use and are seen as a technical requirement of future medical devices for SUDEP prediction and prevention. Widespread adoption requires these technologies to be customizable to adapt to different lifestyles and social situations. A holistic approach should be used in the design of future medical devices to capture several dimensions of PWE and CG epilepsy management journey and uphold communication between healthcare professionals, PWE and CG. CONCLUSION: Data from this study highlight the importance of considering user preferences and experiences in the design of epilepsy management medical devices with potential applicability for SUDEP prediction and prevention. By employing user-centered design methods this research provides valuable insights to inform the development of future SUDEP prediction and prevention devices.

The incidence of sudden unexpected death in epilepsy (SUDEP) in the Republic of Ireland.

BACKGROUND: The incidence of sudden unexpected death in epilepsy (SUDEP) in Ireland has previously been studied in only a small geographical area. Our aim was to calculate an incidence rate for the whole of the Republic of Ireland in 2019. METHODS: All deaths referred to the coroner in 2019 were examined. Those with a history of possible epilepsy were noted and subjected to a more detailed assessment. Cases fulfilling the definition of definite SUDEP were identified. The incidence of SUDEP was calculated using the population of the Republic of Ireland in 2019 and the known prevalence of epilepsy in Ireland. RESULTS: Thirty-three cases of definite SUDEP were identified in the Republic of Ireland in 2019. The estimated incidence of SUDEP in the epilepsy population as a whole was 0.7/1000(0.46 - 0.94) person years. This may be a conservative estimate. More men than women were identified, and most individuals were found dead at home. SUDEP was mentioned on the death certificate in only 52 % of cases. CONCLUSION: This is the first nationwide study of SUDEP incidence in Ireland and provides an incidence rate in keeping with other populations. This work demonstrates that the interrogation of coronial records is a useful way to monitor epilepsy mortality albeit with certain limitations.

Comparing E-Cigarettes and Traditional Cigarettes in Relation to Myocardial Infarction, Arrhythmias, and Sudden Cardiac Death: A Systematic Review and Meta-Analysis.

BACKGROUND: The use of electronic cigarettes (e-cigarettes) as a perceived safer alternative to traditional cigarettes has grown rapidly. However, the cardiovascular risks associated with e-cigarettes compared to regular cigarettes remain unclear. OBJECTIVE: To systematically review and compare the cardiovascular outcomes of e-cigarette use versus traditional cigarette use, focusing on the risks of myocardial infarction, arrhythmias, and sudden death. METHODS: A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Peer-reviewed studies published in English were included if they reported cardiovascular outcomes related to e-cigarette or traditional cigarette use. A total of 20 studies were included, covering observational and interventional studies focusing on heart rate variability, myocardial infarction, arrhythmias, and sudden cardiac events. The quality of the evidence was assessed using the GRADE criteria, and data were extracted and analyzed based on the PICOS (Population, Interventions, Comparisons, Outcomes, and Study designs) framework. RESULTS: The systematic review found that both e-cigarettes and traditional cigarettes pose significant cardiovascular risks, with traditional cigarettes linked to a higher incidence of myocardial infarction, arrhythmias, and sudden cardiac death. E-cigarette users also face increased risks of arrhythmias and myocardial infarction compared to non-smokers, primarily due to the constituents of aerosolized e-liquid, including nicotine and flavorings, which contribute to adverse cardiac effects. Regular e-cigarette use, particularly in combination with traditional cigarette use, was associated with a heightened risk of myocardial infarction. Studies also reported heart function abnormalities, such as systolic and diastolic dysfunction, and reduced ejection fractions. Additionally, changes in heart rate variability, heart rate, and blood pressure were observed, indicating both acute and chronic effects of e-cigarettes on cardiovascular autonomic regulation. CONCLUSIONS: While e-cigarettes may present a lower cardiovascular risk compared to traditional cigarettes, they are not without harm. Both products are linked to increased risks of myocardial infarction and arrhythmias, though traditional cigarettes pose a higher overall threat. Given the limitations in the current evidence base, particularly concerning the long-term effects of e-cigarette use, further research is needed to clarify these cardiovascular risks and inform public health guidelines.

Clinical Course and Treatment of Patients With Apical Aneurysms Due to Hypertrophic Cardiomyopathy.

Background: There is controversy about risk of malignant arrhythmias and stroke in patients with apical aneurysms in hypertrophic cardiomyopathy (HCM). Objectives: The aim of this study was to estimate the associations of aneurysm size and major HCM risk factors with the incidence of lethal and potentially lethal arrhythmias and to estimate incidence of unexplained stroke. Methods: In 108 patients (age 57.4 ± 13.5 years, 37% female) from 3 HCM centers, we assessed American Heart Association/American College of Cardiology guidelines risk factors and initial aneurysm size by echocardiography and cardiac magnetic resonance imaging and assessed outcomes after median 5.9 (IQR: 3.7-10.0) years. Results: Implantable cardioverter defibrillator discharges or sudden cardiac death (SCD) occurred in 21 (19.4%) patients. Of patients with a risk factor, 55% subsequently had ventricular tachycardia (VT), ventricular fibrillation (VF), or SCD at follow-up, compared with 10% in those who did not (P < 0.001). The upper tercile of size had a 5-year cumulative risk of 35%, while the lower tercile had 5-year risk of 6% (P = 0.0046). In those with the smallest aneurysms <2 cm2 and also without risk factors VT, VF, or SCD occurred in only 2.5%. Clinical atrial fibrillation (AF) was prevalent, occurring in 49 (45%). Stroke was commonly associated with AF. Stroke without conventional cause had an incidence of 0.5%/year. Surgery in 19% was effective in reducing symptoms. VT ablation and surgery were moderately effective in preventing recurrent VT. Conclusions: Risk factors and aneurysm size were associated with subsequent VT, VF, or SCD. Patients with aneurysms in the lowest tercile of size have a low cumulative 5-year risk. Clinical AF occurred frequently. Stroke prevalence in absence of known stroke etiologies is uncommon and comparable to risk of severe bleeding.

Extended Ambulatory ECG Monitoring Enhances Identification of Higher-Risk Ventricular Tachyarrhythmias in Patients With Hypertrophic Cardiomyopathy.

BACKGROUND: In hypertrophic cardiomyopathy (HCM), 48-hour ambulatory monitoring has been standard practice to detect nonsustained ventricular tachycardia (NSVT), a sudden death risk marker. Extended-wear ambulatory electrocardiographic (ECG) devices have more recently used for monitoring patients with HCM. OBJECTIVE: We aimed to evaluate NSVT burden identified with continuous ambulatory monitoring for up to 2 weeks compared with initial 48 hours. METHODS: There were 236 consecutive patients with HCM (49 ± 12 years) who underwent 14-day continuous ambulatory monitoring (Zio XT, iRhythm Technologies, San Francisco, CA); diagnostic yield of NSVT compared for initial 48 hours vs extended for 14 days. RESULTS: Of 236 patients, 114 (48%) had ≥ 1 runs of NSVT (median 2) over 14 days. Median length of NSVT was 7 beats (range: 3 to 67) at rates of 120 to 240 beats per minute (bpm) (median, 167 bpm). In 42 of the 114 patients (37%), initial NSVT occurred ≤ 48 hours and in 72 (63%) only during the extended monitoring period (3 to 14 days). Diagnostic yield for detecting NSVT over 14 days was 2.7-fold greater than ≤ 48 hours (P < .001). NSVT judged at higher risk (≥ 8 beats, > 200 bpm, ≥ 2 runs in consecutive 2-day period) was identified more frequently during extended monitoring, diagnostic yield 3-fold greater than ≤ 48 hours (P < .001). CONCLUSION: In HCM, NSVT episodes are frequent; however, in most patients, both NSVT and higher-risk NSVT were not detected during initial 48 hours and were confined solely to extended monitoring period. These data support additional clinical studies to evaluate the significance of NSVT on extended monitoring on sudden death risk in HCM.

The arrhythmic substrate of hypertrophic cardiomyopathy using ECG imaging.

Introduction: Patients with hypertrophic cardiomyopathy (HCM) are at risk for lethal ventricular arrhythmia, but the electrophysiological substrate behind this is not well-understood. We used non-invasive electrocardiographic imaging to characterize patients with HCM, including cardiac arrest survivors. Methods: HCM patients surviving ventricular fibrillation or hemodynamically unstable ventricular tachycardia (n = 17) were compared to HCM patients without a personal history of potentially lethal arrhythmia (n = 20) and a pooled control group with structurally normal hearts. Subjects underwent exercise testing by non-invasive electrocardiographic imaging to estimate epicardial electrophysiology. Results: Visual inspection of reconstructed epicardial HCM maps revealed isolated patches of late activation time (AT), prolonged activation-recovery intervals (ARIs), as well as reversal of apico-basal trends in T-wave inversion and ARI compared to controls (p < 0.005 for all). AT and ARI were compared between groups. The pooled HCM group had longer mean AT (60.1 ms vs. 52.2 ms, p < 0.001), activation dispersion (55.2 ms vs. 48.6 ms, p = 0.026), and mean ARI (227 ms vs. 217 ms, p = 0.016) than structurally normal heart controls. HCM ventricular arrhythmia survivors could be differentiated from HCM patients without a personal history of life-threatening arrhythmia by longer mean AT (63.2 ms vs. 57.4 ms, p = 0.007), steeper activation gradients (0.45 ms/mm vs. 0.36 ms/mm, p = 0.011), and longer mean ARI (234.0 ms vs. 221.4 ms, p = 0.026). A logistic regression model including whole heart mean activation time and activation recovery interval could identify ventricular arrhythmia survivors from the HCM cohort, producing a C statistic of 0.76 (95% confidence interval 0.72-0.81), with an optimal sensitivity of 78.6% and a specificity of 79.8%. Discussion: The HCM epicardial electrotype is characterized by delayed, dispersed conduction and prolonged, dispersed activation-recovery intervals. Combination of electrophysiologic measures with logistic regression can improve differentiation over single variables. Future studies could test such models prospectively for risk stratification of sudden death due to HCM.