Temporal trends in sudden unexpected death in a general population: the Hisayama study

Predicting Risk of Cardiac Arrest in Young Asian Americans: Insights from an Artificial Neural Network Analysis of the Nationwide Cohort

We used the Artificial Neural Network (ANN) model to identify predictors of Sudden Cardiac Arrest (SCA) in a national cohort of young Asian patients in the United States. The National Inpatient Sample (2019) was used to identify young Asians (18-44-year-old) who were hospitalized with SCA. The neural network's predicted criteria for SCA were selected. After eliminating missing data, young Asians (n = 65,413) were randomly divided into training (n = 45,094) and testing (n = 19347) groups. Training data (70%) was used to calibrate ANN while testing data (30%) was utilized to assess the algorithm's accuracy. To determine ANN's performance in predicting SCA, we compared the frequency of incorrect prediction between training and testing data and measured the area under the Receiver Operating Curve (AUC). The 2019 young Asian cohort had 327,065 admissions (median age 32 years; 84.2% female), with SCA accounting for 0.21%. The exact rate of error in predictions vs. tests was shown by training data (0.2% vs 0.2%). In descending order, the normalized importance of predictors to accurately predict SCA in young adults included prior history of cardiac arrest, sex, age, diabetes, anxiety disorders, prior coronary artery bypass grafting, hypertension, congenital heart disease, income, peripheral vascular disease, and cancer. The AUC was 0.821, indicating an excellent ANN model for SCA prediction. Our ANN models performed excellently in revealing the order of important predictors of SCA in young Asian American patients. These findings could have a considerable impact on clinical practice to develop risk prediction models to improve the survival outcome in high-risk patients.

Exploring the Potential of Proteome Analysis as a Promising Tool for Evaluation of Sudden Cardiac Death (SCD) in Forensic Settings: A Literature Review

Sudden cardiac death (SCD) represents a global emergency, with a high number of cases affecting all age groups every year. The prevention of these fatal events requires an accurate knowledge of etiology and pathogenesis, which can vary. Autopsy is an indispensable tool in cases of SCD for diagnostic purposes, as well as for judicial and preventive purposes for family members. Despite the completion of all routine post-mortem investigations, it is often complicated for the forensic pathologist to define the triggering cause of these events. The study of the proteome is proving to be extremely promising in the field of human cardiovascular disease. This paper aims to offer a literature review on the study of the proteome in post-mortem cadaveric biological samples obtained from SCD cases. The aim of this work is to outline the state of the art of the scientific advances that protein analysis can offer in the diagnosis of SCD and the limits that various studies have traced up to now. In conclusion, the work defines the future perspectives of this field in SCD, suggesting strategies to overcome the reported limits and improve the diagnostics of these events.

Use of Implantable Cardioverter-Defibrillators for Primary Prevention of Sudden Cardiac Death in Asia

The effectiveness of primary prevention implantable cardioverter-defibrillators (ICDs) is well established. However, there are several unsolved problems related to ICD use for primary prevention in Asia, including ICD underuse, population differences in underlying heart disease, and the rate of appropriate ICD therapy compared with Western countries. Although the prevalence of ischemic cardiomyopathy in Asia is lower than in Europe and the United States, the mortality rate of Asian patients with ischemic heart disease has been increasing recently. As for the use of ICDs for primary prevention, there have been no randomized clinical trials, and limited data are available in Asia. This review focuses on the unmet needs related to ICD use for primary prevention in Asia.

A systematic review of global autopsy rates in all-cause mortality and young sudden death

Autopsy is the gold standard method for determining cause of death. Young sudden death (SD) is a prototype condition in which autopsy is universally recommended. The aim of this review was to quantify real-world global rates of autopsy in either all-cause death or young SD. A systematic review was conducted. Rates of autopsy in all-cause death and in young SD were determined in each country using scientific and commercial search engines. In total, 59 of 195 countries (30.3%) reported autopsy rates in all-cause death, with rates varying from 0.01%-83.9%. Almost all of these figures derived from academic publications rather than governmental statistics. Only 16 of 195 countries (8.2%) reported autopsy rates in the context of young SD, with reported rates ranging from 5%-100%. The definition of "young" was heterogeneous. No governmental statistics reported autopsy rates in young SD. Risks of bias included inability to verify reported figures, heterogeneity in reporting of clinical vs medicolegal autopsies, and the small number of studies identified overall, resulting in the consistent exclusion of low- and middle-income countries. In conclusion, most countries globally do not report autopsy rates in either all-cause death (69.7%) or in SD (92.8%). Without transparent reporting of autopsy rates, global burdens of disease and rates of sudden cardiac death cannot be reliably calculated.

Brugada Syndrome as a Major Cause of Sudden Cardiac Death in Asians

Brugada syndrome (BrS) is one of the main inherited arrhythmia syndromes causing ventricular fibrillation (VF) and sudden cardiac death in young to middle-aged men, especially in Asians. The diagnosis of BrS is based on spontaneous or drug-provoked type 1 Brugada electrocardiogram. The current reliable therapy for BrS patients with VF history is the implantation of an implantable cardioverter-defibrillator. As for BrS patients without VF history, how asymptomatic BrS patients should effectively be treated is still uncertain because risk stratification of the BrS is still inadequate. Various parameters and combinations of several parameters have been reported for risk stratification of BrS. The SCN5A gene is believed to be the only gene that is responsible for BrS, and it has been reported to be useful for risk stratification. This review focuses on risk stratification of BrS patients, and focuses specifically on BrS patients of Asian descent.

Genetic screening in heritable thoracic aortic disease—rationale, potentials and pitfalls

Thoracic aortic aneurysms are silent yet deadly clinical entities which may elude detection until an acutely life-threatening aortic dissection or rupture occurs. Approximately 20% of patients with thoracic aortic aneurysms or dissection have a positive family history, indicating a strong genetic component to the aetiology. Genetic screening in such hereditary thoracic aortic disease (HTAD) may thus be beneficial in detecting causative genetic mutations in affected patients, identifying asymptomatic family members who may be at risk, and in guiding the optimal timing of preventative surgery in those with confirmed genetic aortopathy. Genetic screening can facilitate personalised aortic care tailored to an individual's specific genetic abnormality, with the aim of mitigating the significant morbidity burden and premature mortality associated with HTAD. This review examines the rationale for genetic screening in HTAD, its potential applications, current limitations and potential future directions.

Aortic gene dictionary in the precision medicine era—update from the Aortic Institute at Yale New Haven

This paper reviews the current understanding of the inherited, genetic nature of thoracic aortic aneurysm and dissection (TAAD), as well as the practice of genetic testing for thoracic aortic disease at the Aortic Institute at Yale-New Haven Hospital.

A review of the causes and risk factors for sudden unexpected death in the young

Sudden unexpected death in the young (SUDY) is a tragic event resulting in the fatality of seemingly healthy individuals between the ages of one and 40 years. Whilst studies have been performed on sudden unexpected death in infants, children, and adults respectively, little is known about trends in risk factors and causes of death of SUDY cases. Understanding the factors surrounding these deaths could lead to targeted interventions for at-risk individuals. Hence, a systematic approach to investigate the reported possible causes of SUDY was employed using three major databases and Primo, wherein 67 relevant articles were identified and 2 additional guidelines were read. Sudden unexpected death in epilepsy and sudden cardiac events were well-established causes of death with risk factors such as male predominance, substance use and a familial history identified. It was acknowledged that while the cause of death is established following post-mortem examination in many cases, some remain non-specific or undetermined. Considering the genetic etiology, these cases would be ideal candidates for molecular autopsies in the future. Thus, this review emphasized the significance of acquiring the relevant information to aid in resolving cause of death of these SUDY cases and subsequently highlighted the potential for further studies on risk factors and the value of molecular autopsies.

Association of glucose tolerance status with pancreatic β- and α-cell mass in community-based autopsy samples of Japanese individuals: The Hisayama Study

AIMS/INTRODUCTION

Changes in histologically quantified β- and α-cell mass during the development of glucose intolerance have not been fully elucidated. The aim of the present study was to explore differences in β- and α-cell mass according to the glucose tolerance status.

MATERIALS AND METHODS

Autopsy samples from a total of 103 individuals (40 with normal glucose tolerance, 31 with prediabetes and 32 with type 2 diabetes mellitus) who underwent a 75-g oral glucose tolerance test within 5 years before death were selected from 643 community-based autopsy samples collected from 2002 to 2016. Fractional β-cell area (BCA) and α-cell area were quantified with Image Pro Plus software. Associations of BCA and α-cell area with glucose tolerance status were assessed using a linear regression analysis, and Spearman's correlation coefficients between glycemic markers and β-cell function were estimated.

RESULTS

The mean values of BCA decreased significantly with worsening glucose tolerance status (mean ± standard error 1.85 ± 0.10% in normal glucose tolerance, 1.59 ± 0.11% in prediabetes and 1.17 ± 0.11% in type 2 diabetes mellitus, P for trend < 0.001), whereas there was no significant association between α-cell area and glucose tolerance status. BCA was inversely correlated with fasting and 2-h plasma glucose levels during oral glucose tolerance test and glycated hemoglobin measurement, and positively correlated with disposition index (all P < 0.01).

CONCLUSIONS

β-Cell mass decreased significantly with worsening glucose tolerance, from the stage of prediabetes, in the Japanese population. Prevention of declining β-cell mass before the onset of glucose intolerance is important to reduce the burden of type 2 diabetes mellitus.

Intra-day change in occurrence of out-of-hospital ventricular fibrillation in Japan: The JCS-ReSS study

BACKGROUND

Real-world evidence of out-of-hospital ventricular fibrillation (VF), especially regarding intra-day change, remains unclear. We aimed to investigate that age- and gender-dependent difference of intra-day change of VF occurrence.

METHOD

We enrolled 71,692 patients (males: 56,419 [78.7%], females: 15,273 [21.3%]) in whom cardiac VF had been documented from the 2005-2015 All-Japan Utstein Registry data. Subjects were divided into four groups: group-I (<18 years old), group-II (18-39), group-III (40-69), and group-IV (≥70). Among four groups in each of male and female, we compared the intra-day change of VF occurrence, and evaluated the risk factors of the unfavorable neurologic outcomes at 1 month after VF.

RESULTS

Regardless of age, the incidence of VF was significantly greater in male than in female subjects. In male subjects, VF in group-I, III and IV occurred higher at daytime, however, group-II had no intra-day difference because group-II had a higher VF events at midnight~ early morning compared with other aged groups (Poisson regression analysis, p = .03). While in female, each group showed similar intra-day pattern of VF occurrence. Logistic regression analysis revealed that some of the clinical parameters such as time periods from call receipt to first shock and the presence of bystander cardiopulmonary resuscitation were important for risk of 30-day neurologically unfavorable outcomes.

CONCLUSIONS

The intra-day change of VF occurrence was age-dependently different in males but not in females, suggesting age- and gender-dependent differences in underlying cardiac diseases. These might affect the significant difference in unfavorable neurologic outcome.

Spontaneous ruptured aortic plaque and injuries: insights for aging and acute aortic syndrome from non-obstructive general angioscopy

Recent advances in non-obstructive general angioscopy (NOGA) have enabled the detection of aortic atherosclerosis. The incidence of spontaneous ruptured aortic plaques (SRAPs) and aortic injuries was found to be high in patients diagnosed with or suspected of having coronary artery disease. These facts may result in a paradigm shift for diseases such as aging and acute aortic syndrome because the incidence of systemic embolic diseases and aortic disease are assumed be high. Aortic thromboembolism has been thought to be mainly iatrogenic and is referred to as "cholesterol embolization syndrome" or "cholesterol crystal embolization", although the cholesterol crystals (CCs) were not demonstrated routinely as real images. Atheromatous materials, fibrins, calcifications, macrophages, and a mixture of such substances are released through a puff or puff-chandelier rupture. Among atheromatous materials, CCs can be easily detected clinically in sampled blood via polarized light microscopy. Atheromatous materials include rich CCs and free monolayers, and multilayer CCs are released when the atheromatous materials from vulnerable plaques break into pieces, such as in puff or puff-chandelier rupture. Released SRAPs seem to be asymptomatic; however, accumulation of SRAPs referred to as accumulated spontaneous asymptomatic plaques may cause aging through systemic "embolic" processes, such as mechanical obstruction and an inflammasome pathway. Unique findings in "atherosclerotic" acute aortic syndrome, such as a clear boundary between the dissected lesion and the normal lesion, fissure/fissure bleeding suggesting an entry or a reentry, and subintimal blood flow detected through NOGA are reported. Fissure/fissure bleeding and subintimal blood flow may be the first or last triggers of "atherosclerotic" acute aortic syndrome. Pre-emptive diagnosis and risk stratification of acute "atherosclerotic" aortic dissection and feedback for endovascular therapy may be enabled through the use of NOGA in the future.

Trends in the use of implantable cardioverter-defibrillators for prevention of sudden cardiac arrest: A South Korean nationwide population-based study

BACKGROUND

The benefits of implantable cardioverter-defibrillators (ICDs) for the prevention of sudden cardiac arrest (SCA) are well established. However, a significant knowledge gap remains regarding current indications and utilization of ICDs in real-world settings in Asia.

METHODS

Patients who underwent ICD implantation in South Korea from 2007 to 2015 were identified using the Health Insurance Review and Assessment Service database. We investigated trends in use of ICD for the prevention of SCA.

RESULTS

A total of 4649 ICDs were implanted during 9 years. ICDs were implanted in 1448 (31.2%) patients for primary prevention and in 3201 (68.8%) for secondary prevention. The proportion of ICDs for primary prevention increased from 6.1% in 2007 to 41.9% in 2015. Primary prevention was more frequent in older (≥40 years) recipients (34.4% vs. 14.6%, P < .0001). The rates of ICD implantation for primary prevention were highest for nonischemic dilated cardiomyopathy (55.1%) and lowest (9.7%) for inherited primary arrhythmia syndrome (IPAS).

CONCLUSION

Our data showed a trend of progressively increasing rates of ICD implantation in Asia, especially for primary prevention of SCA. Primary prevention as an indication for ICD in patients with IPAS remained low.

Integrative analyses of myocardial lipidome and proteome implicate mitochondrial dysfunction in lethal ventricular tachyarrhythmia (LVTA) induced by acute myocardial ischemia (AMI)

Lethal ventricular tachyarrhythmia (LVTA) is the most prevalent electrophysiological event leading to sudden cardiac death (SCD). In this study, the myocardial lipidome and proteome were analysed in rats experiencing LVTA as a consequence of acute myocardial ischemia (AMI). Results showed that 257 lipid species and 814 myocardial proteins were disrupted during LVTA. Cardiolipin (CL), phosphatidylcholine (PC), phosphatidylethanolamine (PE), ceramide (Cer), lysophosphatidylethanolamine (LPE), lysophosphatidylcholine (LPC), phosphatidylglycerol (PG), and lysophosphatidylserine (LPS) were down-regulated; whereas sphingosine (SO) and diacylglycerol (DG) were up-regulated. Enrichment analysis of these proteins suggested mitochondrial dysfunction. Most of the differential lipids showed a high degree of interaction with the core differentially expressed proteins. Seven lipid pathways, including DG → PE, PE → LPE, PA → DG, PC → DG, PE → PA, Cer → SM, and LPE → LPC, were active during the process. Activation of LPE → PE could be partially confirmed by proteomic results. CL (72:7), PE (42:4), and LPE (P-18:0) jointly represent a promising diagnostic markers for LVTA. Collectively, we discovered marked disturbances of the lipidome and proteome in the myocardia of LVTA rats, mainly involving dysfunction of the mitochondrial respiratory chain.

The effects of flipped learning for bystander cardiopulmonary resuscitation on undergraduate medical students

OBJECTIVES

To compare bystander cardiopulmonary resuscitation skills retention between conventional learning and flipped learning for first-year medical students.

METHODS

A post-test only control group design. A total of 108 participants were randomly assigned to either the conventional learning or flipped learning. The primary outcome measures of time to the first chest compression and the number of total chest compressions during a 2-minute test period 6 month after the training were assessed with the Mann-Whitney U test.

RESULTS

Fifty participants (92.6%) in the conventional learning group and 45 participants (83.3%) in the flipped learning group completed the study. There were no statistically significant differences 6 months after the training in the time to the first chest compression of 33.0 seconds (interquartile range, 24.0-42.0) for the conventional learning group and 31.0 seconds (interquartile range, 25.0-41.0) for the flipped learning group (U=1171.0, p=0.73) or in the number of total chest compressions of 101.5 (interquartile range, 90.8-124.0) for the conventional learning group and 104.0 (interquartile range, 91.0-121.0) for the flipped learning group (U=1083.0, p=0.75). The 95% confidence interval of the difference between means of the number of total chest compressions 6 months after the training did not exceed a clinically important difference defined a priori.

CONCLUSIONS

There were no significant differences between the conventional learning group and the flipped learning group in our main outcomes. Flipped learning might be comparable to conventional learning, and seems a promising approach which requires fewer resources and enables student-centered learning without compromising the acquisition of CPR skills.

The ratio of serum eicosapentaenoic acid to arachidonic acid and risk of cancer death in a Japanese community: The Hisayama Study

Background

Whether the intake of eicosapentaenoic acid (EPA) or arachidonic acid (AA) affects the risk of cancer remains unclear, and the association between the serum EPA:AA ratio and cancer risk has not been fully evaluated in general populations.

Methods

A total of 3098 community-dwelling subjects aged ≥40 years were followed up for 9.6 years (2002–2012). The levels of the serum EPA:AA ratio were categorized into quartiles (<0.29, 0.29–0.41, 0.42–0.60, and >0.60). The risk estimates were computed using a Cox proportional hazards model. The same analyses were conducted for the serum docosahexaenoic acid to arachidonic acid (DHA:AA) ratio and individual fatty acid concentrations.

Results

During the follow-up period, 121 subjects died of cancer. Age- and sex-adjusted cancer mortality increased with lower serum EPA:AA ratio levels (P trend<0.05). In the multivariable-adjusted analysis, the subjects in the first quartile of the serum EPA:AA ratio had a 1.93-fold (95% confidence interval, 1.15–3.22) greater risk of cancer death than those in the fourth quartile. Lower serum EPA concentrations were marginally associated with higher cancer mortality (P trend<0.11), but the serum DHA or AA concentrations and the serum DHA:AA ratio were not (all P trend>0.37). With regard to site-specific cancers, lower serum EPA:AA ratio was associated with a higher risk of death from liver cancer. However, no such associations were detected for deaths from other cancers.

Conclusions

These findings suggest that decreased level of the serum EPA:AA ratio is a significant risk factor for cancer death in the general Japanese population.

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Lower serum EPA:AA ratio was significantly associated with higher cancer mortality.

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The risk of death from liver cancer increased with lower serum EPA:AA ratio.

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No significant association was found between serum DHA:AA ratio and cancer death.

Guilt by association: a paradigm for detection of silent aortic disease

Detection of clinically silent thoracic aortic aneurysm (TAA) is challenging due to the lack of symptoms (until aortic rupture or dissection occurs). A large proportion of TAA are identified incidentally while imaging a patient for other reasons. However, recently several clinical "associates" of TAA have been described that can aid in identification of silent TAA. These "associates" include intracranial aneurysm, aortic arch anomalies, abdominal aortic aneurysm (AAA), simple renal cysts (SRC), bicuspid aortic valve, temporal arteritis, a positive family history of aneurysm disease, and a positive thumb-palm sign. In this article we examine these associates of TAA and the data supporting their involvement with asymptomatic TAA.

Dyspnoea as a predictor of cause-specific heart/lung disease mortality in Bangladesh: a prospective cohort study

BACKGROUND

The spectrum of mortality outcomes by cause in populations with/without dyspnoea has not been determined. The study aimed to evaluate whether dyspnoea, a symptom, predicts cause-specific mortality differences between groups. The hypothesis was that diseases that result in chronic dyspnoea, those originating from the heart and lungs, would preferentially result in heart and lung disease mortality in those with baseline dyspnoea (relative to no dyspnoea) when followed over time.

METHODS

A population-based sample of 11 533 Bangladeshis was recruited and followed for 11-12 years and cause-specific mortality evaluated in those with and without baseline dyspnoea. Dyspnoea was ascertained by trained physicians. The cause of death was determined by verbal autopsy. Kaplan-Meier survival curves, the Fine-Gray competing risk hazards model and logistic regression models were used to determine group differences in cause-specific mortality.

RESULTS

Compared to those not reporting dyspnoea at baseline, the adjusted HRs were 6.4 (3.8 to 10.7), 9.3 (3.9 to 22.3), 1.8 (1.2 to 2.8), 2.2 (1.0 to 5.1) and 2.8 (1.3 to 6.2) for greater risk of dying from chronic obstructive pulmonary disease (COPD), asthma, heart disease, tuberculosis and lung cancer, respectively. In contrast, there was a similar risk of dying from stroke, cancer (excluding lung), liver disease, accidents and other (miscellaneous causes) between the dyspnoeic and non-dyspnoeic groups. In addition, the HR was 2.1 (1.7 to 2.5) for greater all-cause mortality in those with baseline dyspnoea versus no dyspnoea.

CONCLUSIONS

Dyspnoea, ascertained by a single question with binary response, predicts heart and lung disease mortality. Individuals reporting dyspnoea were twofold to ninefold more likely to die of diseases that involve the heart and/or lungs relative to the non-dyspnoeic individuals. Therefore, in those with chronic dyspnoea, workup to look for the five common dyspnoeic diseases resulting in increased mortality (COPD, asthma, heart disease, tuberculosis and lung cancer), all treatable, should reduce mortality and improve the public health.

Paradigm for Detecting Silent Thoracic Aneurysm Disease

Thoracic aortic aneurysms (TAA) pose a serious detection challenge owing to their clinically silent nature. Only a small fraction of TAAs cause symptoms in patients. However, the mortality burden of this disease in the population is significant, given the high lethality of such complications as aortic rupture and dissection. Widespread screening for TAA has not been shown to be cost-effective. Therefore, currently most patients with a TAA are identified incidentally during an imaging study conducted for other reasons. Once a TAA diagnosis is established, prophylactic surgical treatment can safely be performed for aneurysms of the ascending aorta, aortic arch, and descending or thoracoabdominal aorta, thus preventing aneurysm-related death. To facilitate early detection of TAA, recent studies have identified several "associates" of TAA that may be useful in making a timely diagnosis. These "associates" include intracranial aneurysm, aortic arch anomalies, abdominal aortic aneurysm, simple renal cysts, bicuspid aortic valve, temporal arteritis, a positive family history of aneurysm disease, and a positive thumb-palm sign, among others. Although for many of these "associates" the underlying mechanism that would explain the association remains to be elucidated, the clinical correlation is strong enough to suggest screening patients with these findings for TAA. This article introduces the "Guilt by Association" paradigm for detection of silent thoracic aortic disease based on detection of clinical markers associated with this condition.

The spectrum of epidemiology underlying sudden cardiac death

Sudden cardiac death (SCD) from cardiac arrest is a major international public health problem accounting for an estimated 15%-20% of all deaths. Although resuscitation rates are generally improving throughout the world, the majority of individuals who experience a sudden cardiac arrest will not survive. SCD most often develops in older adults with acquired structural heart disease, but it also rarely occurs in the young, where it is more commonly because of inherited disorders. Coronary heart disease is known to be the most common pathology underlying SCD, followed by cardiomyopathies, inherited arrhythmia syndromes, and valvular heart disease. During the past 3 decades, declines in SCD rates have not been as steep as for other causes of coronary heart disease deaths, and there is a growing fraction of SCDs not due to coronary heart disease and ventricular arrhythmias, particularly among certain subsets of the population. The growing heterogeneity of the pathologies and mechanisms underlying SCD present major challenges for SCD prevention, which are magnified further by a frequent lack of recognition of the underlying cardiac condition before death. Multifaceted preventative approaches, which address risk factors in seemingly low-risk and known high-risk populations, will be required to decrease the burden of SCD. In this Compendium, we review the wide-ranging spectrum of epidemiology underlying SCD within both the general population and in high-risk subsets with established cardiac disease placing an emphasis on recent global trends, remaining uncertainties, and potential targeted preventive strategies.

Global burden of Sudden Cardiac Death and insights from India

Sudden Cardiac death (SCD) is a major clinical event causing adverse impact on global economy. This review summarizes the available epidemiological data on SCD from different parts of the world. It contrasts the Indian and global perception on the issues influencing data collection, burden of SCD and sudden deaths occurring following Myocardial Infarction. The differences in data from India and rest of the world are highlighted.