Incidence Of Sudden Cardiac Death Research Articles

What Do We Know So Far About Ventricular Arrhythmias and Sudden Cardiac Death Prediction in the Mitral Valve Prolapse Population? Could Biomarkers Help Us Predict Their Occurrence?

To summarize currently available data on the topic of mitral valve prolapse (MVP) and its correlation to the occurrence of atrial and ventricular arrhythmias. To assess the prognostic value of several diagnostic methods such as transthoracic echocardiography, transesophageal echocardiography, cardiac magnetic resonance, cardiac computed tomography, electrocardiography, and electrophysiology concerning arrhythmic episodes. To explore intra and extracellular biochemistry of the cardiovascular system and its biomarkers as diagnostic tools to predict rhythm disturbances in the MVP population. MVP is a common and mainly benign valvular disorder. It affects 2-3% of the general population. MVP is a heterogeneous and highly variable phenomenon with three structural phenotypes: myxomatous degeneration, fibroelastic deficiency, and forme fruste. Exercise intolerance, supraventricular tachycardia, and chest discomfort are the symptoms that are often paired with psychosomatic components. Though MVP is thought to be benign, the association between isolated MVP without mitral regurgitation (MR) or left ventricle dysfunction, with ventricular arrhythmia (VA) and sudden cardiac death (SCD) has been observed. The incidence of SCD in the MVP population is around 0.6% per year, which is 6 times higher than the occurrence of SCD in the general population. Often asymptomatic MVP population poses a challenge to screen for VA and prevent SCD. Therefore, it is crucial to carefully assess the risk of VA and SCD in patients with MVP with the use of various tools such as diagnostic imaging and biochemical and genetic screening.

Circadian Regulation of Cardiac Arrhythmias and Electrophysiology.

Circadian rhythms in physiology and behavior are ≈24-hour biological cycles regulated by internal biological clocks (ie, circadian clocks) that optimize organismal homeostasis in response to predictable environmental changes. These clocks are present in virtually all cells in the body, including cardiomyocytes. Many decades ago, clinicians and researchers became interested in studying daily patterns of triggers for sudden cardiac death, the incidence of sudden cardiac death, and cardiac arrhythmias. This review highlights historical and contemporary studies examining the role of day/night rhythms in the timing of cardiovascular events, delves into changes in the timing of these events over the last few decades, and discusses cardiovascular disease-specific differences in the timing of cardiovascular events. The current understanding of the environmental, behavioral, and circadian mechanisms that regulate cardiac electrophysiology is examined with a focus on the circadian regulation of cardiac ion channels and ion channel regulatory genes. Understanding the contribution of environmental, behavioral, and circadian rhythms on arrhythmia susceptibility and the incidence of sudden cardiac death will be essential in developing future chronotherapies.

Cardiac Sarcoidosis-Diagnostic and Therapeutic Challenges.

Sarcoidosis is a multisystem disorder of unknown etiology. The leading hypothesis involves an antigen-triggered dysregulated T-cell-driven immunologic response leading to non-necrotic granulomas. In cardiac sarcoidosis (CS), the inflammatory response can lead to fibrosis, culminating in clinical manifestations such as atrioventricular block and ventricular arrhythmias. Cardiac manifestations frequently present as first and isolated signs or may appear in conjunction with extracardiac manifestations. The incidence of sudden cardiac death (SCD) is high. Diagnosis remains a challenge. For a definite diagnosis, endomyocardial biopsy (EMB) is suggested. In clinical practice, compatible findings in advanced imaging using cardiovascular magnetic resonance (CMR) and/or positron emission tomography (PET) in combination with extracardiac histological proof is considered sufficient. Management revolves around the control of myocardial inflammation by employing immunosuppression. However, data regarding efficacy are merely based on observational evidence. Prevention of SCD is of particular importance and several guidelines provide recommendations regarding device therapy. In patients with manifest CS, outcome data indicate a 5-year survival of around 90% and a 10-year survival in the range of 80%. Data for patients with silent CS are conflicting; some studies suggest an overall benign course of disease while others reported contrasting observations. Future research challenges involve better understanding of the immunologic pathogenesis of the disease for a targeted therapy, improving imaging to aid early diagnosis, assessing the need for screening of asymptomatic patients and randomized trials.

Can we screen for heart disease in children at public health centres? A multicentre observational study of screening for heart disease with a risk of sudden death in children

Sudden cardiac death in children is a rare event, but of great social significance. Generally, it is related to heart disease with a risk of sudden cardiac death (SCD), which may occur with cardiovascular symptoms and/or electrocardiographic markers; thus, a primary care paediatrician (PCP) could detect them. Therefore, we proposed a study that assesses how to put into practice and conduct a cardiovascular assessment within the routine healthy-child check-ups at six and twelve years of age; that reflects cardiovascular signs and symptoms, as well as the electrocardiographic alterations that children with a risk of SCD in the selected population present; and that assesses the PCP’s skill at electrocardiogram (ECG) interpretation. In collaboration with PCPs, primary care nurses, and paediatric cardiologists, an observational, descriptive, multicentre, cross-sectional study was carried out in the Balearic Islands (Spain), from April 2021 to January 2022, inclusive. The PCPs gathered patient data through forms (medical record, electrocardiogram, and physical examination) and sent them to the investigator, together with the informed consent document and electrocardiogram. The investigator passed the electrocardiogram on to the paediatric cardiologists for reading, in an identical form to those the paediatricians had filled in. The variables were collected, and a descriptive analysis performed. Three paediatric cardiologists, twelve PCPs, and nine nurses from seven public health centres took part. They collected the data from 641 patients, but 233 patients did not participate (in 81.11% due to the PCP’s workload). Therefore, the study coverage was around 64%, representing the quotient of the total number of patients who participated, divided by the total number of patients who were eligible for the study. We detected 30 patients with electrocardiographic alterations compatible with SCD risk. Nine of these had been examined by a paediatric cardiologist at some time (functional murmur in 8/9), five had reported shortness of breath with exercise, and four had reported a family history of sudden death. The physical examination of all the patients whose ECG was compatible with a risk of SCD was normal. Upon analysing to what extent the ECG results of the PCP and the paediatric cardiologist agreed, the percentage of agreement in the final interpretation (normal/altered) was 91.9%, while Cohen’s kappa coefficient was 31.2% (CI 95%: 13.8–48.6%). The sensitivity of the ECG interpretation by the PCP to detect an ECG compatible with a risk of SCD was 29% and the positive predictive value 45%.     Conclusions: This study lays the foundations for future SCD risk screening in children, performed by PCPs. However, previously, it would be important to optimise their training in reading and interpreting paediatric ECGs.What is Known:• In Spain at present, there is a programme in place to detect heart disease with a risk of sudden death [1], but it targets only children who are starting on or are doing a physical activity as a federated sport. Implementing such screening programmes has proven effective in several countries [2]. However, several studies showed that the incidence of sudden cardiac death is no higher in children competing in sport activities than in those who do not do any sport [3]. This poses an ethical conflict, because at present, children who do not do any federated sport are excluded from screening. According to the revised literature, so far, only in two studies did they screen the child population at schools, and in both, they successfully detected patients with heart disease associated to the risk of sudden death [4, 5]. We have found no studies where the screening of these features was included within the routine healthy-child check-ups by primary care paediatricians.What is New:• We did not know whether—in our setting, at present—the primary care paediatrician could perform a screening method within the routine healthy-child check-ups, in order to detect presumably healthy children at risk of sudden cardiac death, as they present one of the SCD risks. In this regard, we proposed our project: to assess how to put into practice and conduct a cardiovascular assessment via SCD risk screening in the healthy child population by primary care paediatricians and appraise primary care paediatricians’ skills in identifying the electrocardiographic alterations associated with SCD risk. The ultimate intention of this pilot study was to make it possible, in the future, to design and justify a study aimed at universalising cardiovascular screening and achieving a long-term decrease in sudden cardiac death events in children.

Incidence of Sudden Cardiac Death in Low- and Middle-Income Countries: A Systematic Review of Cohort Studies.

Sudden cardiac death (SCD) is a leading cause of mortality worldwide and, in recent years, has become an urgent public health concern in low- and middle-income countries (LMICs). Data from LMICs, however, remains limited. As such, the aim of this article is to systematically review the current literature on the incidence of SCD in LMICs to inform policymakers and identify potential research gaps. A search of PubMed and Embase was utilized to capture the targeted condition, outcome, and setting. Only peer-reviewed cohort studies in LMICs reporting SCD incidence estimates in the general population of individuals aged ≥1 year were eligible for selection. Papers providing incidence data for specific types of SCD, including sudden coronary death or death from sudden cardiac arrest, were also included. After deduplication, 1941 citations were identified and screened. Seven studies representing four countries-Cameroon, China, India, and Iran-met the criteria for inclusion and were considered in our analysis. The crude incidence rate for SCD ranged from 19.9 to 190 cases per 100,000 person-years, while age-adjusted rates ranged from 33.6 to 230 cases per 100,000 person-years. There was notable variability in methods utilized to ascertain SCD cases. These findings suggest that the incidence of all-cause SCD in LMICs and may exceed that of high-income countries; however, observed disparities may be partly attributable to differences in case ascertainment methods. Additional research is needed to better understand the true incidence of SCD in developing countries. It is crucial that future studies across regions utilize standard diagnostic criteria and methodology for identifying SCD, which would provide a framework by which to compare outcomes between settings.

Ondansetron and the Risk of Sudden Cardiac Death among Individuals Receiving Maintenance Hemodialysis.

Individuals receiving hemodialysis have high incidence of sudden cardiac death and are susceptible to QT interval prolonging medication-related cardiac complications. Ondansetron, an antiemetic with known QT prolonging potential, is associated with fatal arrythmias in the general population when administered intravenously. The cardiac safety of ondansetron in the hemodialysis population is unknown. We conducted a new-user, active-comparator, cohort study using US Renal Data System data (2012-2019) to examine the association between the initiation of oral ondansetron vs. antiemetics with lesser QT prolonging potential (promethazine, metoclopramide or prochlorperazine) and the 10-day risk of sudden cardiac death among individuals receiving hemodialysis. We used inverse probability of treatment weighted survival models to estimate adjusted hazard ratios (aHRs), risk differences (aRDs), and 95% confidence intervals (CIs). We used an intention-to-treat approach in which non-sudden cardiac death was considered a competing event. We examined additional cardiac outcomes in secondary analyses. Of the 119,254 study patients, 64,978 (54.5%) initiated ondansetron, and 54,276 (45.5%) initiated a comparator antiemetic. Initiation of ondansetron versus a comparator antiemetic was associated with higher relative and absolute 10-day risks of sudden cardiac death, aHR (95% CI) = 1.44 (1.08, 1.93); aRD (95% CI) = 0.06% (0.01%, 0.11%). The number needed to harm was 1,688. Analyses of additional cardiac outcomes yielded similar findings. Compared with initiation of antiemetics with lesser QT prolonging potential, initiation of ondansetron was associated with higher short-term cardiac risks among people receiving hemodialysis.

Powering the future: Exploring self-charging cardiac implantable electronic devices and the Qi revolution.

The incidence and prevalence of cardiovascular diseases (CVD) have risen over the last few decades worldwide, resulting in a cost burden to healthcare systems and increasingly complex procedures. Among many strategies for treating heart diseases, treating arrhythmias using cardiac implantable electronic devices (CIEDs) has been shown to improve quality of life and reduce the incidence of sudden cardiac death. The battery-powered CIEDs have the inherent challenge of regular battery replacements depending upon energy usage for their programmed tasks. Nanogenerator-based energy harvesters have been extensively studied, developed, and optimized continuously in recent years to overcome this challenge owing to their merits of self-powering abilities and good biocompatibility. Although these nanogenerators and others currently used in energy harvesters, such as biofuel cells (BFCs) exhibit an infinite spectrum of uses for this novel technology, their demerits should not be dismissed. Despite the emergence of Qi wireless power transfer (WPT) has revolutionized the technological world, its application in CIEDs has yet to be studied well. This review outlines the working principles and applications of currently employed energy harvesters to provide a preliminary exploration of CIEDs based on Qi WPT, which may be a promising technology for the next generation of functionalized CIEDs.

Do Implantable Cardioverter-Defibrillators Prevent Sudden Cardiac Death in End-Stage Renal Disease Patients on Dialysis?

Chronic kidney disease patients appear to be predisposed to heart rhythm disorders, including atrial fibrillation/atrial flutter, ventricular arrhythmias, and supraventricular tachycardias, which increase the risk of sudden cardiac death. The pathophysiological factors underlying arrhythmia and sudden cardiac death in patients with end-stage renal disease are unique and include timing and frequency of dialysis and dialysate composition, vulnerable myocardium, and acute proarrhythmic factors triggering asystole. The high incidence of sudden cardiac deaths suggests that this population could benefit from implantable cardioverter-defibrillator therapy. The introduction of implantable cardioverter-defibrillators significantly decreased the rate of all-cause mortality; however, the benefits of this therapy among patients with chronic kidney disease remain controversial since the studies provide conflicting results. Electrolyte imbalances in haemodialysis patients may result in ineffective shock therapy or the appearance of non-shockable underlying arrhythmic sudden cardiac death. Moreover, the implantation of such devices is associated with a risk of infections and central venous stenosis. Therefore, in the population of patients with heart failure and severe renal impairment, periprocedural risk and life expectancy must be considered when deciding on potential device implantation. Harmonised management of rhythm disorders and renal disease can potentially minimise risks and improve patients' outcomes and prognosis.

Case report: A case of an anomalous right coronary artery arising from the left coronary cusp.

Abstract
 An anomalous origin of the right coronary artery is usually asymptomatic. It is mostly found incidentally on an invasive diagnostic angiogram. It does lead to an increased risk of sudden cardiac death, especially in younger patients. We present a case of a 41-year-old who had presented to the hospital with complaints of chest pain. The patient was evaluated by cardiology who performed an angiography that identified an anomalous origin of the right coronary artery arising from the left coronary cusp but no evidence of coronary artery disease. Once identified, these anomalous vessels should be corrected surgically, as these conditions increase the risk of sudden cardiac death arrhythmia and ischemic events.
  
 INTRODUCTION
 Anomalous aortic origin of the right coronary artery (AAORCA) is an uncommon congenital malformation with varying clinical presentations ranging from asymptomatic to sudden cardiac death (SCD). Those with symptoms or high-risk lesions are usually managed by unroofing or reimplantation, coronary artery bypass graft (CABG), AAORCA treated with right internal memory artery graft with proximal RCA ligation.
  
 CASE DESCRIPTION
 A 41-year-old female patient with obesity and hypertension presented with a 1-year history of intermittent exertional substernal pressure radiating to left shoulder and back. The pain, which lasted about 10 minutes per episode, had been more frequent and intense over the past week.Upon initial evaluation, she was hypertensive at 150/90 mmHg and heart rate  60 bpm. Blood work was unremarkable, including negative serial troponin levels. Electrocardiography showed sinus bradycardia without ischaemic changes. Anomalous origin of RCA was incidentally discovered from computed tomography (CT) of the chest. Coronary angiography and ascending aortography were then performed, which revealed a patent RCA originating from the left coronary cusp (Fig. 1A). CT heart angiography with reconstruction revealed the RCA ostium in the left coronary cusp with a malignant course between the aorta and pulmonary artery and without an obvious intramural segment
 Discussion:
  
  An anomalous origin of the right coronary artery (RCA) is a rare congenital anomaly that was first described in 1948 by White and Edwards. After carrying out angiography in 126,595 patients, Yamanaka and Hobbs reported the incidence of anomalous origin of the right and left coronary arteries as 136 (0.107%) and 22 (0.017%), respectively. The prevalence of an anomalous origin of RCA (ARCA) arising from the left coronary cusp with an inter-arterial course varies between 0.026% and 0.25%. An ARCA is more common than the anomalous origin of the left coronary artery (ALCA), but the latter is shown to be responsible for up to 85% of sudden cardiac deaths (SCD) related to the anomalous origins of arteries. Most coronary anomalies are detected incidentally on diagnostic angiography and are clinically insignificant; some, however, have been associated with an increased risk of SCD. It is second only to hypertrophic cardiomyopathy as a leading cause of SCD in young athletes. Mechanical compression of the RCA by the great vessels, which dilate and compress the RCA during periods of increased stroke volume, is the usual explanation for coronary ischemia. Patients usually have no ischemic changes on an electrocardiogram (ECG) at rest; however, multi-detector computed tomography (MDCT) is being used to evaluate the course of anomalous vessels outlying their relative positions to the aorta and the pulmonary artery. It also gives additional information regarding any stenotic lesion in these anomalous vessels. Echocardiography (Echo), magnetic resonance angiography (MRA), MCDT, and cardiac catheterization are all complementary diagnostic tools for evaluating anomalous coronary arteries [10]. While it is agreed that surgical correction is the standard of care for ALCA, when found, the management for right ARCA is more complicated. Treatment options for these patients include observation with medical therapy, percutaneous intervention (stenting), or surgery. Early diagnosis of coronary artery anomalies based on the patients’ symptoms can help decrease the incidence of sudden cardiac deaths, fatal arrhythmias, and ischemic events in the high-risk population.
  
 Conclusions 
  
 Coronary anomalies should be suspected in symptomatic young patients with a normal cardiac workup. Non-invasive imaging modalities such as a CTCA can help establish the diagnosis

Study of the Histopathological Changes in the Heart in Postmortem/Autopsy Cases in Tertiary Care Center

Context: There has been a significant increase in global cardiac-related fatalities, particularly over the last five decades. In India, cardiovascular diseases have emerged as a prevalent condition. Moreover, the incidence of sudden cardiac death has shown a steady rise worldwide. Aims: The aim of this study was to research how frequently cardiac disease was found during postmortem/autopsy cases and how it affects sudden death. Materials and Methods: The research was conducted at the Department of Pathology, SRTR, GMC, Ambajogai, India. One hundred and eighty cardiac specimens were examined from October 2019 to October 2021. Formalin-fixed heart specimens had multiple sections cut out of them at 4–5 mm intervals. The tissues underwent preparation, followed by sectioning into 4 μm thickness using paraffin. The standard staining method of hematoxylin and eosin was used to stain the samples. Different cardiac histomorphological alterations were assessed. Results: The study included 180 autopsy cases. The highest numbers of cases were observed in the age group of 31–40 years (20.2%). Triple-vessel involvement was seen in the majority of 61.5% of cases, out of 180 cases, 52.7% of cases were of hypertrophy. Conclusions: The research highlights the prevalence of cardiovascular diseases, particularly atherosclerosis and hypertrophy. Notably, sudden death cases showed a distinct distribution across the study years, with males being predominantly affected. This underscores the urgent need for preventive measures and interventions to prevalent cardiovascular conditions effectively.

Trends in sudden cardiac death mortality in Italy, 2013-2019.

We sought to analyse the incidence of sudden cardiac deaths (SCDs) amongst subjects aged less than 39years in Italy and its time trend between 2013 and 2019. Data regarding cause-specific mortality and population size by sex in 5-year age groups were extracted from the World Health Organization (WHO) mortality database. Decedents reporting the codes I46.1, I45.6, I47.2, I41.9, R09.2 and R96.0 of the International Classification of Disease-10 (ICD-10) coding system, were extracted. The age-adjusted mortality rates (AAMRs), with relative 95% confidence intervals (CIs) stratified by sex, were determined using the direct method. Joinpoint regression analyses were used to identify periods with statistically distinct log linear trends in SCD-related death rates. To calculate nationwide annual trends in SCD-related mortality, we assessed the annual and average annual per cent change (AAPC) and relative 95% CIs. Over the study period, 314 deaths [220 males (70.0%) and 94 females] were due to SCD corresponding to a 0.06 per 100,000 per year (0.10 per 100,000 in males and 0.04 per 100,000 in females, respectively). Proportional mortality slightly increased, without reaching the statistical significance (p = 0.82) from 3.06 to 3.56 per 100 deaths, with a similar trend in both sexes. Joinpoint regression analysis revealed a plateau in age-standardised SCD-related mortality over the period [AAPC: -4.2 (95% CI: -24.0 to 20.8, p = 0.71], which was consistent between males and females. In Italy, SCD remains a public health issue of concern in the last decade after adjusting for age.

Sudden Cardiac Death in Patients Under 49 Years Including Adolescents: A single-centre study from Oman.

This study aimed to identify the incidence of sudden cardiac death (SCD0 in adult patients under the age of 49 years, including adolescents with an out-of-hospital cardiac arrest that presented to the emergency department of a tertiary care hospital. This retrospective cross-sectional study was conducted at the Royal Hospital, Muscat, Oman, between January 2015 and December 2019. All patients with out-of-hospital cardiac arrest were enrolled. The incidence of SCD was evaluated. Information about the patient's demographic data, the site of cardiac arrest, the mode of arrival, the duration of pre-arrest symptoms and if cardiopulmonary resuscitation was performed was gathered. Survival data at 3-year follow-up was obtained. A total of 117 out of 769 (15%) patients met the criteria for SCD. Male gender was predominant, with a median age of 33 years. In about 79.5% of the patients, cardiac arrest was witnessed. Only 43 patients (36.8%) received cardiopulmonary resuscitation at the arrest site; 21 patients (17.9%) had a shockable rhythm and 96 patients (82.1%) had a non-shockable rhythm. Spontaneous circulation was returned in 15 patients (12.8%). Nine patients (7.7%) were discharged from the hospital and 8 (6.8%) survived at least 36 months. The study findings indicate the prevalence of SCD among patients who experienced a cardiac arrest outside the hospital. Unfortunately, only a small number of patients were able to survive in the long term. By implementing preemptive screening for individuals and their families, it may be possible to prevent SCD and improve outcomes for those affected.

Incidence, risk assessment and prevention of sudden cardiac death in cardiomyopathies.

Cardiomyopathies are a significant contributor to cardiovascular morbidity and mortality, mainly due to the development of heart failure and increased risk of sudden cardiac death (SCD). Despite improvement in survival with contemporary treatment, SCD remains an important cause of mortality in cardiomyopathies. It occurs at a rate ranging between 0.15% and 0.7% per year (depending on the cardiomyopathy), which significantly surpasses SCD incidence in the age- and sex-matched general population. The risk of SCD is affected by multiple factors including the aetiology, genetic basis, age, sex, physical exertion, the extent of myocardial disease severity, conduction system abnormalities, and electrical instability, as measured by various metrics. Over the past decades, the knowledge on the mechanisms and risk factors for SCD has substantially improved, allowing for a better-informed risk stratification. However, unresolved issues still challenge the guidance of SCD prevention in patients with cardiomyopathies. In this review, we aim to provide an in-depth discussion of the contemporary concepts pertinent to understanding the burden, risk assessment and prevention of SCD in cardiomyopathies (dilated, non-dilated left ventricular, hypertrophic, arrhythmogenic right ventricular, and restrictive). The review first focuses on SCD incidence in cardiomyopathies and then summarizes established and emerging risk factors for life-threatening arrhythmias/SCD. Finally, it discusses validated approaches to the risk assessment and evidence-based measures for SCD prevention in cardiomyopathies, pointing to the gaps in evidence and areas of uncertainties that merit future clarification.

Sudden Cardiac Death in National Collegiate Athletic Association Athletes: A 20-Year Study.

Understanding the incidence, causes, and trends of sudden cardiac death (SCD) among young competitive athletes is critical to inform preventive policies. This study included National Collegiate Athletic Association athlete deaths during a 20-year time frame (July 1, 2002, through June 30, 2022). Athlete deaths were identified through 4 separate independent databases and search strategies (National Collegiate Athletic Association resolutions list, Parent Heart Watch database and media reports, National Center for Catastrophic Sports Injury Research database, and insurance claims). Autopsy reports and medical history were reviewed by an expert panel to adjudicate causes of SCD. A total of 143 SCD cases in National Collegiate Athletic Association athletes were identified from 1102 total deaths. The National Collegiate Athletic Association resolutions list identified 117 of 143 (82%), the Parent Heart Watch database or media reports identified 89 of 143 (62%), the National Center for Catastrophic Sports Injury Research database identified 63 of 143 (44%), and insurance claims identified 27 of 143 (19%) SCD cases. The overall incidence of SCD was 1:63 682 athlete-years (95% CI, 1:54 065-1:75 010). Incidence was higher in male athletes than in female athletes (1:43 348 [95% CI, 1:36 228-1:51 867] versus 1:164 504 [95% CI, 1:110 552-1:244 787] athlete-years, respectively) and Black athletes compared with White athletes (1:26 704 [1:20 417-1:34 925] versus 1:74 581 [1:60 247-1:92 326] athlete-years, respectively). The highest incidence of SCD was among Division I male basketball players (1:8188 [White, 1:5848; Black, 1:7696 athlete-years]). The incidence rate for SCD decreased over the study period (5-year incidence rate ratio, 0.71 [95% CI, 0.61-0.82]), whereas the rate of noncardiovascular deaths remained stable (5-year incidence rate ratio, 0.98 [95% CI, 0.94-1.04]). Autopsy-negative sudden unexplained death (19.5%) was the most common postmortem examination finding, followed by idiopathic left ventricular hypertrophy or possible cardiomyopathy (16.9%) and hypertrophic cardiomyopathy (12.7%), in cases with enough information for adjudication (118 of 143). Eight cases of death were attributable to myocarditis over the study period (1 case from January 1, 2020, through June 30, 2022), with none attributed to COVID-19 infection. SCD events were exertional in 50% of cases. Exertional SCD was more common among those with coronary artery anomalies (100%) and arrhythmogenic cardiomyopathy (83%). The incidence of SCD in college athletes has decreased. Male sex, Black race, and basketball are associated with a higher incidence of SCD.

Sudden cardiac death in women: causes of death at premenopausal and postmenopausal age

Abstract Background Among women the incidence of sudden cardiac death (SCD) is lower than in men but still significant. On average menopause occurs at the age of 51.4 years. During the last decades the proportion of nonischemic SCD seems to have increased in both sexes. In postmenopausal women both the incidence and severity of the coronary artery disease (CAD) increase unpredictably 3-fold compared to premenopausal women of similar age. Purpose The aim of this study was to determine whether the causes of SCD differ among women at premenopausal and postmenopausal age. Methods The Fingesture study has systematically collected clinical and autopsy data from SCD victims in Northern Finland between 1998 and 2017. The cohort consists of 5,869 SCD victims of which 1,238 are women (21.1%). Women aged ≥52 years were considered as postmenopausal and ≤51 years old as premenopausal as the direct information of the menopause lacked due to the retrospective nature of this autopsy-based data. Results Approximately one fifth of the SCD victims were women (21.1%; P<0.001). The mean age of female subjects was 70.1±13.1 years (P<0.001). Only 7.9% of the women experienced SCD under the age of 52 years (P<0.001). Causes of death among women at premenopausal and postmenopausal age are represented in Table 1. Amongst all women 71.7% of the SCDs were ischemic (P<0.001). Majority of those women were at postmenopausal age but CAD caused still one third of the SCDs of the women at premenopausal age (33.7%, P<0.001). Overall nonischemic causes of death were more common at premenopausal age compared to postmenopausal women. Statistically significant nonischemic causes of death were primary myocardial fibrosis (PMF), obesity cardiomyopathy (CM), myocarditis, arrhythmogenic right ventricular cardiomyopathy (ARVC) and dilated CM. PMF was considerably more common cause of death among premenopausal women than in postmenopausal women (19.4 % vs. 3.9%, P<0.001), as was also the obesity CM (16.3% vs. 5.3%, P<0.001). Myocarditis caused the death of 5.1% of the premenopausal women but only 1.3% of the postmenopausal women (P=0.004). Both dilated CM (P=0.021) and ARVC (P=0.008) were the cause of death of 2.0% of the premenopausal women and 0.3-0.4% of the postmenopausal women. Subjects with anatomically and histologically normal finding at autopsy were mainly at premenopausal age (2.0% vs. 0.3%, P=0.008) even though the overall amount of cases remained low. Conclusions SCD at premenopausal age is rare. One third of the premenopausal SCDs are ischemic even though majority of the SCDs at premenopausal age are nonischemic etiology. Especially the prevalence of PMF and obesity CM were remarkably higher among premenopausal women compared to the postmenopausal age group emphasizing the role of genetics and lifestyle behind the SCD of premenopausal women.Table 1.

Proportion of ischemic and nonischemic sudden cardiac death by age and sex

Abstract Background Among women the incidence of sudden cardiac death (SCD) is significant, but lower than in men. During the last decades the proportion of nonischemic SCD seems to have increased in both sexes. Coronary artery disease (CAD) have changed to be sickness of elderly women rather than middle-aged men as in women the prevalence and incidence of CAD starts to increase after the menopause. Purpose The aim of this study was to illustrate how the amount and the proportions of ischemic and nonischemic SCD vary between women and men in different age groups. Methods The Fingesture study has systematically collected clinical and autopsy data from SCD victims in Northern Finland between 1998 and 2017. The cohort consists of 5,869 SCD victims. Results Approximately one fifth of the SCD victims were women (21.1%; P<0.001). Three out of four SCDs were ischemic (74.8%; P<0.001) and majority of the ischemic SCD victims were men (79.8%; P=0.005). The mean age of female victims was 70.1±13.1 years and 63.5±11.8 years among male victims (P<0.001). Amongst women one SCD out of 15 occurred to the subject under 50 years of age (6.7%; P<0.001) whereas in men one SCD victim out of nine was under 50 years old (11.4%; P<0.001). A nonischemic SCD was observed in 350 women and in 1,127 men (P<0.001). The proportion of nonischemic death was higher among women than in men in every age group from under 30 years of age to subjects of 84 years old studied in five year periods (Figure 1). Only age group of 65-69 years in women and 60-64 years in men were not statistically significant, otherwise all the P-values were ≤0.003. The difference in proportion of ischemic and non-ischemic SCD was the smallest among subjects of 40-49 years of age amongst the proportion of ischemic SCD increased rapidly both in women and in men as the prevalence of non-ischemic SCD started to decrease (Figure 1). Amongst SCD victims aged 40-44 years 47.9% of the deaths of men (P<0.001) and 41.7% of the deaths of women (P<0.001) were ischemic etiology. Among women aged 50-54 years over half of the SCDs were ischemic (53.1%; P<0.001). The gender difference in proportion of ischemic SCD was actually the smallest in age groups 40-49 years and after 70 years of age, and its largest in the middle in favor of men. (Figure 1). After the age of 70 years the total amount of SCDs started to plateau in men and decrease in the amount of SCDs was seen in men after the age of 75 years as in women the plateau phase was not reached until the age of 80 years (Figure 2). Conclusion Minority of the SCDs occur under the age of 50 years, especially among women. The proportion of nonischemic SCD was higher in women than in men despite the age. However, already in pre- and perimenopausal age the proportion of ischemic SCD in women was remarkable and the amount of ischemic SCD increased until the age of 80 years emphasizing the need of early primary and secondary prevention of CAD also in women not only in men.Figure 1.Figure 2.

Abstract 13427: Incidence and Causes of Sudden Cardiac Death in National Collegiate Athletic Association Athletes: A 20-year Study

Background: The incidence and causes of sudden cardiac death (SCD) among young competitive athletes impact prevention strategies yet remain incompletely understood. Methods: National Collegiate Athletic Association (NCAA) athlete deaths from 7/1/2002-6/30/2022 were identified through 4 independent databases/search strategies. Autopsy reports and medical history were reviewed by an expert panel to adjudicate causes of SCD. Poisson regression was used to calculate incidence rate ratios (IRR) for 5-year intervals over the 20-year study. Results: A total of 143 SCD cases were identified among 1102 athlete deaths and 9,106,516 athlete-years (AYs). The incidence of SCD among NCAA athletes was 1:63,682 AYs [95% CI 1:54,065, 1:75,010]. Incidence was higher in males compared to females (1:43,348 vs. 1:164,504 AYs) and Black compared to White athletes (1:27,217 vs. 1:74,581 AYs). The highest incidence of SCD was among Division 1 male basketball players (1:8,188; White 1:5,848; Black 1:7,696 AYs). The incidence rate for SCD decreased over the study period (5-year IRR 0.71 [95% CI 0.61,0.82]), whereas the rate of non-cardiovascular deaths remained stable (5-year IRR 0.98 [95% CI 0.94,1.04]; Figure 1A ). Autopsy-negative sudden unexplained death (AN-SUD, 19.5%) was the most common post-mortem exam finding, followed by idiopathic left ventricular hypertrophy/possible cardiomyopathy (CM, 16.9%) and hypertrophic CM (12.7%) in cases with enough information for adjudication (118/143, Figure 1B ). There were 8 cases of myocarditis, with none attributed to COVID-19 infection. SCD events occurred most commonly during exertion among athletes with coronary artery anomalies (100%) and arrhythmogenic CM (83%), whereas AN-SUD and hypertrophic CM had a higher proportion of non-exertional SCD (44% and 40%, respectively). Conclusions: The incidence of SCD in college athletes has decreased. Male sex, Black race, and basketball are associated with a higher incidence of SCD.

Abstract 12725: Day of the Week Variation of Unexpected Sudden Cardiac Death

Introduction: Data on day of the week (septadian) variation of unexpected sudden cardiac death (SCD) are limited. Methods: We evaluated the incidence of unexpected SCD on different days of the week in a consecutive series of 5,869 SCD victims from Northern Finland [the Fingesture study (Finnish Genetic Study of Arrhythmic Events)]. A medico-legal autopsy was performed on all unexpected sudden death victims as it is mandatory in Finland. The autopsies were performed between the years 1998-2017. Results: The incidence of unexpected SCD in the region of Northern Finland with approximately 600,000 inhabitants on average was 55 per 100,000 inhabitants per year. The mean incidence of unexpected SCD was higher during the days form Friday to Sunday (peaking on Saturday) than during the days from Monday to Thursday (8.54±0.72 vs. 7.22±0.19 SCDs per day of the week per 100,000 inhabitants per year, p<0.001, respectively) (Figure 1). The number of unexpected SCD victims with alcohol in blood was higher during the days form Friday to Sunday (peaking on Saturday) than during the days from Monday to Thursday (Figure 2). Conclusion: The incidence of unexpected SCD was highest during the days form Friday to Sunday, peaking on Saturday. There was a similar distribution of the number of SCD victims with alcohol in blood during the days of the week, suggesting that alcohol drinking with its adverse influences contributes to the septadian variation of unexpected SCD.

Abstract 17673: Sudden Cardiac Death as the First Manifestation of Heart Disease

Background: Clinical risk stratification is most challenging in the subgroup of individuals who present with sudden cardiac death (SCD) as the first manifestation of heart disease (SCD-FM) and there is a lack of current era population-based data. Hypothesis: Occurrence of SCD-FM SCD differs by ethnicity and access to health care. Methods: Consecutive out-of-hospital cases of SCD attended by emergency medical services were ascertained prospectively from a large ongoing population-based study in the Southwest US (population ~ 850K, 2015-2022) using an established multi-source ascertainment and adjudication process. A detailed review was conducted of the lifetime clinical record and available autopsy data, for each individual. SCD-FM cases were defined as SCD with no prior heart disease diagnosis. We calculated annual age-standardized incidence of overall SCD and SCD-FM per 100,000 residents using US census data. Ethnicity-stratified incidence of SCD-FM was calculated. Occurrence of all health care visits prior to SCD was evaluated. Results: From a total of 2681 SCD cases (age 71 ± 16, female 35%) age adjusted incidence of SCD was 40[38-41] per 100,000 out of which SCD-FM was 15[14-16] per 100,000 (n=1019 (38%), age 67±18, female 33%). There was no difference in SCD-FM incidence between Hispanic and non-Hispanic residents (15 [13-17] vs 15 [14-17], p=0.84). Individuals younger than 65 yr were more likely to have SCD-FM compared to those older than 65 yr (50% vs 33%, p <0.001). We observed that 91% of SCD-FM had visited healthcare providers and 3% had cardiac evaluations performed. Conclusion: A significantly higher proportion of SCD-FM were age <65 but the proportion of SCD-FM did not differ by ethnicity. The vast majority of SCD-FM (91%) underwent health care visits prior to SCD but cardiac evaluations were rare (3%). These findings highlight the need to discover and develop user-friendly, cost-effective pre-screening methods to reduce SCD-FM in the general population.

Abstract 15856: Genetics, Pathologic Characteristics, and Burden of Lethal Hypertrophic Cardiomyopathy Among Countywide Sudden Deaths

Background: Annual incidence of sudden cardiac death (SCD) is reported at 1% in cohorts with known hypertrophic cardiomyopathy (HCM), but these estimates presume arrhythmic cause and miss occult cases dying before diagnosis. Hypothesis: Prospective surveillance and postmortem investigation of community sudden deaths will uncover the true burden of presumed SCD (pSCD) and arrhythmic death (SAD) attributable to HCM. Objectives: Determine characteristics and precise contribution of HCM to population pSCD and SAD. Methods: POST SCD (POstmortem SysTematic Investigation of Sudden Cardiac Death) is a prospective cohort study using autopsy, clinical records, and toxicology to adjudicate arrhythmic (potentially rescuable with implantable defibrillator) or non-arrhythmic (e.g., tamponade, overdose) causes among pSCDs 0-90 years in San Francisco County. We included all incident cases from 2/1/11-3/1/14 (n=525) and approximately every 3rd day from 3/1/14-9/1/22 (n=497). We identified HCM victims via 3 parallel approaches: 1) pathology criteria; 2) echocardiogram (TTE) review; 3) genetic analysis. Results: Of 1022 pSCDs in the 11-year study period, we identified 13 cases with HCM, yielding a 2% contribution to arrhythmic death burden: 10 met pathology criteria; 2 via review of 203 TTEs (missed on initial report); 1 with pathogenic ALPK3 mutation. Only 2 of 13 (15%) pSCDs with HCM had premortem diagnosis. A greater proportion of pSCDs with HCM had autopsy-confirmed arrhythmic cause than pSCDs without HCM (11/13 [85%] vs. 547/1009 [54%], p=0.03). HCM contribution to pSCD burden decreased with age (p=0.003), highest among victims <35 years, accounting for 7.1% (6/84) of pSCDs and 9.4% (3/32) of SADs. Genetic testing of 317 consented pSCDs (5/12 meeting pathologic or TTE HCM criteria) yielded pathogenic mutations in 40% (2/5), and identified 1 additional case without clinical phenotype. Conclusions: In this 11-year countywide postmortem study, HCM meeting pathologic, clinical, or genetic criteria was associated with autopsy-confirmed arrhythmic cause of sudden death, accounting for 2% of SADs, highest in cases <35 years. As 85% of cases were undiagnosed before pSCD, the true burden of HCM-related sudden death may be substantially underestimated.