Guidelines for autopsy investigation of sudden cardiac death: 2017 update from the Association for European Cardiovascular Pathology

Heart weight must not be measured before dissection during autopsies

During autopsies, weighing the heart is a standard procedure. In addition to myocardial pathologies, heart size, and ventricular wall thickness, heart weight is a common parameter to describe cardiac pathology and should be recorded as accurately as possible. To date, there exists no standard for recording heart weight at autopsy, although some authors recommend weighing the heart after dissection and removal of blood and blood clots. In the study presented, the hearts of 58 decedents were weighed after being dissected out of the pericardial sac (a), after dissection using the short-axis or inflow-outflow method with manual removal of blood and blood clots (b), and after rinsing and drying (c). Depending on the dissection method, the heart weight was 7.8% lower for the inflow-outflow method and 11.6% lower for the short-axis method after dissection compared to before and correspondingly 2.9% to 5% lower again after rinsing and drying respectively. Accordingly, the heart should be dissected, blood and blood clots removed, rinsed with water, and dried with a surgical towel after dissection, before weighing.

Postmortem genetic analysis of 17 sudden cardiac deaths identified nonsense and frameshift variants in two cases of arrhythmogenic cardiomyopathy

Sudden death, or unexpected natural death of a healthy individual, is a serious problem in all nations. Sudden cardiac death (SCD) mainly due to ischemic heart diseases is the top cause of sudden death. However, there are pathophysiological conditions, referred to as sudden arrhythmic death syndrome, in which no apparent lesion can be identified even after complete conventional or ordinary autopsy. While postmortem genetic analyses have accumulated evidence about underlying genetic abnormality in such cases, the precise relationships between genetic background and the phenotype have been largely elusive. In this study, a retrospective investigation of 17 autopsy cases in which lethal arrhythmia was suspected to be the cause of death was carried out. Genetic analysis focusing on 72 genes reported to be associated with cardiac dysfunctions was performed, in combination with detailed histopathological and postmortem imaging examination, and a family study. As a result, in two cases of suspected arrhythmogenic cardiomyopathy (ACM), we found a nonsense variant in PKP2 and frameshift variant in TRPM4 gene. In contrast, the other 15 cases showed no morphological changes in the heart despite the presence of a frameshift variant and several missense variants, leaving the clinical significance of these variants obscure. The findings of the present study suggest that nonsense and frameshift variants could be involved in the morphological abnormality in cases of SCD due to ACM, while missense variants alone rarely contribute to massive structural changes in the heart.

Primary myocardial fibrosis - a distinct entity characterized by heterogeneous histology

Primary myocardial fibrosis (PMF), defined as myocardial fibrosis in the absence of identifiable causes, may represent a common alternative phenotype in various cardiomyopathies and contribute to sudden cardiac death (SCD). No previous definitions of histopathological characteristics exist for PMF. We aimed to evaluate whether common features of fibrosis could be identified. PMF cases (n = 28) were selected from the FinGesture cohort consisting of 5,869 SCD victims that underwent a medicolegal autopsy. Twelve trauma controls and 10 ischemic heart disease cases were selected as reference groups. Further 3 PMF cases and 5 ischemic heart disease cases from autopsies performed in the University of Copenhagen, Denmark, were selected for a validation substudy. Relative area of fibrosis, amount of diffuse and perivascular fibrosis, and location of fibrosis were assessed from left ventricle myocardial samples stained with Masson trichrome. Further evaluations were performed with alpha-smooth muscle actin (α-SMA), vimentin, and CD68 stainings. Mean relative area of fibrosis was 5.8 ± 10.7%, 1.0 ± 0.7%, and 7.0 ± 7.4% in PMF, trauma controls, and ischemic cases, respectively. Fibrosis in the PMF group was mostly located in other sites than the endocardium. Most cases with fibrosis had vimentin-positive but α-SMA-negative stromal cells within fibrotic areas. Histopathologically, PMF represents a heterogeneous entity with variable fibrotic lesions affecting the whole myocardium and a suggested significant role of fibroblasts. These findings may bring validation to PMF being a common manifestation of cardiomyopathies. Evidently, PMF stands out as a particular entity demanding special attention as a cause of SCD.

Post-mortem genetic testing in sudden cardiac death and genetic screening of relatives at risk: lessons learned from a Czech pilot multidisciplinary study

Sudden cardiac death (SCD) might have an inherited cardiac condition background. Genetic testing supports post-mortem diagnosis and screening of relatives at risk. Our aim is to determine the feasibility of a Czech national collaboration group and to establish the clinical importance of molecular autopsy and family screening. From 2016 to 2021, we have evaluated 100 unrelated SCD cases (71.0% males, age: 33.3 (12.8) years). Genetic testing was performed by next-generation sequencing utilizing a panel of 100 genes related to inherited cardiac/aortic conditions and/or whole exome sequencing. According to autopsy, cases were divided into cardiomyopathies, sudden arrhythmic death syndrome, sudden unexplained death syndrome, and sudden aortic death. We identified pathogenic/likely pathogenic variants following ACMG/AMP recommendations in 22/100 (22.0%) of cases. Since poor DNA quality, we have performed indirect DNA testing in affected relatives or in healthy parents reaching a diagnostic genetic yield of 11/24 (45.8%) and 1/10 (10.0%), respectively. Cardiological and genetic screening disclose 83/301 (27.6%) relatives at risk of SCD. Genetic testing in affected relatives as starting material leads to a high diagnostic yield offering a valuable alternative when suitable material is not available. This is the first multidisciplinary/multicenter molecular autopsy study in the Czech Republic which supports the establishment of this type of diagnostic tests. A central coordinator and proper communication among centers are crucial for the success of a collaboration at a national level.

Evaluation of the cardiovascular risk induced by cannabis use from a series of 43 autopsy cases

The aim of this monocentric observational autopsy study was to confirm the existence of a link between cannabis use and cardiovascular risk. It was based on the analysis of autopsy findings, cardiovascular pathological findings, and toxicological data in 43 autopsy cases of people who died with tetrahydrocannabinol (THC) in their blood over a 2-year period. Hair analysis was performed when available (n = 40) to distinguish between occasional and chronic cannabis use and to take into account other possible exposures, including smoking, drug consumption, and the use of other drugs of abuse (mainly cocaine, heroin, and amphetamine). A statistically significant association (Fisher's exact test, p < 0.001) was found between cannabis use, an undetermined manner of death, and the presence of an arrhythmogenic cardiac condition. An association was also found between cannabis use and the presence of advanced coronary heart disease (p = 0.01), heart disease (including ischemic heart disease, p = 0.003), or cardiomyopathy (p = 0.01). Through its systemic vascular action, cannabis could be a factor in triggering sudden death in subjects with arrhythmogenic cardiac conditions. In view of this finding, the mode of death of subjects who died in the presence of THC in the blood would in most cases be an "accident." These results highlight the potential adverse cardiac effects associated with cannabis use.

Malpratice claims in cardiology and cardiac surgery: A medico-legal issue

Medical liability has become a challenge in every physician's modern practice with the consequent loss of the physician's autonomy and an increase in "defensive medicine". From this perspective, the role of Legal Medicine in assessing medical liability has become increasingly specific and a homogenization of the methods of ascertainment is increasingly necessary, since such a process can contribute to strengthening the guarantees in professional liability procedures. Focusing on malpractice claims in the field of cardiology, the complexity of the management of cardiac pathologies and the frequency of severe adverse events implies the importance of a multi-disciplinary approach, together with the application of a shared ascertainment methodology. In particular, it is essential for the forensic pathologist to collaborate with experts in cardio-pathology, cardiology and/or cardiac surgery in cases of alleged medical liability in the cardiologic field and to follow the guidelines which have been produced to assist the expert dealing with deaths reflecting cardiac disease, in order to prevent criticism of case analysis in medico-legal environments and to promote the standardization of the structure of the juridical-legislative medical malpractice lawsuits.

Differences among young unwitnessed sudden cardiac death, according to time from last seen alive: Insights from a 15-year nationwide study

BACKGROUND

More than half of all sudden cardiac deaths (SCDs) are unwitnessed, but the composition of the unwitnessed SCD population is poorly described.

OBJECTIVE

The purpose of this study was to compare clinical and autopsy characteristics of young unwitnessed SCD subjects, based on the time from last contact to being found dead.

METHODS

All unwitnessed SCD subjects aged 1-35 years in Denmark from 2000-2014 identified through a multisource approach were included. Time from last seen alive to being found dead was dichotomized to <1 hour or 1-24 hours. Clinical characteristics and autopsy results were compared, and predictors of autopsy were assessed by logistic regression.

RESULTS

Of 440 unwitnessed SCD subjects, 366 (83%) had not been seen alive within 1 hour of being found dead. Comorbidities differed between the groups, with more epilepsy (17% vs 5%) and psychiatric diseases (13% vs 7%) in the 24-hour group. Patients in the 24-hour group died more frequently during sleep (64% vs 23%), the autopsy rate was higher (75% vs 61%), and deaths were more often unexplained after autopsy (69% vs 53%). Having been seen within 1 hour of death independently decreased the chance of being autopsied (odds ratio 0.51; 95% confidence interval 0.27-1.00; P = .0497).

CONCLUSION

The majority of unwitnessed SCD subjects had not been seen alive within 1 hour of being found dead. Clinical- and autopsy-related characteristics differed between the 2 groups. Differences were mainly attributable to death-related circumstances and comorbidities. Excluding SCD cases not seen alive within 1 hour of being found dead would severely underestimate the burden of SCD.

Postmortem biochemistry in deaths from ischemic heart disease

Ischemic heart disease (IHD) is one of the leading causes of morbidity and sudden cardiac death worldwide and is an important public health problem. The presence of ischemia in clinical applications can be detected by ECG, biochemical markers, and radiological methods. Myocardial infarction is also frequently encountered in forensic autopsies. Postmortem diagnosis is determined as a result of histopathological examinations and additional exclusionary examinations (toxicology, microbiology, etc.). However, routine histopathological examinations are insufficient, especially when death occurs in the early period of ischemia. It creates a problem for forensic pathologists and forensic medicine specialists in such cases of sudden cardiac death. Postmortem biochemistry is one of the important and promising disciplines in which forensic applications work in order to diagnose these cases correctly. The issue of whether biomarkers used in the diagnosis of myocardial infarction in clinical studies can be used reliably in postmortem cases has been discussed by forensic medicine researchers for some time. This manuscript aims to review and summarize biomarkers belonging to various categories that have been studied in IHD-related deaths, in biological fluids taken at autopsy, or in animal experiments. Our study shows that the postmortem use of biochemical markers in the diagnosis of IHD yields promising results. However, it should not be forgotten that postmortem biochemistry is different from clinical applications due to its dynamics and that the body causes unpredictable changes in markers in the postmortem process. Therefore, comprehensive studies are needed to evaluate the postmortem stability of these markers in different biological fluids, their significance among various causes of death, and whether they are affected by any variable (Cardiopulmonary resuscitation, Postmortem interval, medications, etc.) before they are routinely applied. It is suggested by the authors that the cut-off values of biomarkers whose significance has been proven by these studies should be determined and that they should be used in this way in routine applications.

The Role of miRNA Expression Profile in Sudden Cardiac Death Cases

Sudden cardiac death (SCD) is one of the leading causes of death in the world and for this reason it has attracted the attention of numerous researchers in the field of legal medicine. It is not easy to determine the cause in a SCD case and the available methods used for diagnosis cannot always give an exhaustive answer. In addition, the molecular analysis of genes does not lead to a clear conclusion, but it could be interesting to focus attention on the expression level of miRNAs, a class of non-coding RNA of about 22 nucleotides. The role of miRNAs is to regulate the gene expression through complementary binding to 3'-untraslated regions of miRNAs, leading to the inhibition of translation or to mRNA degradation. In recent years, several studies were performed with the aim of exploring the use of these molecules as biomarkers for SCD cases, and to also distinguish the causes that lead to cardiac death. In this review, we summarize experiments, evidence, and results of different studies on the implication of miRNAs in SCD cases. We discuss the different biological starting materials with their respective advantages and disadvantages, studying miRNA expression on tissue (fresh-frozen tissue and FFPE tissue), circulating cell-free miRNAs in blood of patients affected by cardiac disease at high risk of SCD, and exosomal miRNAs analyzed from serum of people who died from SCD.

Histiocytoid cardiomyopathy presenting as sudden death in an 18-month-old infant

Histiocytoid cardiomyopathy (HC) is an arrhythmogenic disorder, usually involving children under two years of age with a strong Caucasian and female predominance. The disease is fatal in the vast majority and diagnosis is nearly always established at autopsy, but this is only possible with adequate myocardial sampling. Meticulous gross and histological examination of the heart in collaboration with a cardiovascular-trained pathologist maximises the opportunity to make specific diagnoses (and therefore rule out the differentials of SIDS, SUDC and child abuse), guide genetic testing, and inform potentially life-saving medical interventions for blood relations. We present a typical HC case presenting as sudden death, without prodrome, in a previously healthy 18-month-old boy. The disease is characterised histologically by discrete groups of enlarged, polygonal histiocyte-like cells with distinct margins and abundant faintly eosinophilic foamy cytoplasm. Cells often contain coarse granules, microvacuoles and irregular, round nuclei. In our case, dysplastic fascicles were predominantly located immediately deep to the endocardium of the left ventricle. We report our own autopsy findings with histological images, and discuss the expected clinical, morphological and ultrastructural features of the disease.

[Cardiac sarcoidosis as an infrequent cause of sudden death in asymptomatic young patients]

Cardiac involvement in sarcoidosis has been described in both symptomatic and asymptomatic patients. The aim of this report is to further the understanding of sarcoidosis and its clinical presentation. We report the autopsy and toxicology results of two cases of sudden death in young men. A 37-year-old male had generalized sarcoidosis, in mediastinal glands and intramyocardial sarcoid granulomas in the left ventricle, which had caused a 14mm thickening of the ventricular wall and a secondary dilated myocardiopathy causing sudden death. A 27-year-old male had extensive sarcoidosis of the lungs and mediastinum. Granulomas with a fibrotic background were found in the cardiac wall which could have originated an arrhythmogenic mechanism causing sudden death. Post-mortem study including careful examination of cardiac conduction pathways are vital to ascertain the cause of sudden death.

Prevalence of illicit drug use in young patients with sudden cardiac death

BACKGROUND

Illicit drug use may accelerate coronary disease and cardiac hypertrophy or stimulate arrhythmias. Rates of illicit drug use in young patients with sudden cardiac death (SCD) are uncertain.

OBJECTIVE

The purpose of this study was to identify rates of illicit drug use in young patients with SCD.

METHODS

A prospective statewide registry identified out-of-hospital patients with cardiac arrest aged 18-50 years from April 2019 to April 2021. Clinical characteristics were compared between patients with and without illicit drug use (defined by toxicological results or reported regular use). Illicit drugs included amphetamine-type substances, cocaine, heroin, cannabis, and other drugs.

RESULTS

A total of 554 (40.2%) of 1378 patients had confirmed cardiac cause of out-of-hospital cardiac arrest, with 523 undergoing toxicological assessment. There were 170 patients (32.5%) having either positive toxicology for illicit drugs (n = 138) or negative toxicology but reported regular drug use (n = 32). Patients with SCD and illicit drug use were more commonly male (81.2% vs 72.3%; P = .028), smokers (38.8% vs 19.8%; P ≤ .0001), and excess alcohol drinkers (30.6% vs 20.6%; P = .012) and had a psychiatric diagnosis (38.8% vs 25.7%; P = .002), lower body mass index (29.4 kg/m2 vs 31.7 kg/m2; P = .0063), and lower rates of hypertension (10.6% vs 18.6%; P = .019). Death commonly occurred while sedentary (47.5%) or during sleep (45.8%). Accounting for these baseline differences, there were no differences in rates of coronary disease or cardiomyopathy. Cannabis (n = 106) was the most common illicit drug identified and polysubstance abuse occurred frequently (n = 25).

CONCLUSION

Approximately one-third of young patients with SCD have positive toxicology at the time of death or reported frequent use of illicit drugs, with high rates of polysubstance abuse.

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.

The Lancet Commission to reduce the global burden of sudden cardiac death: a call for multidisciplinary action

Despite major advancements in cardiovascular medicine, sudden cardiac death (SCD) continues to be an enormous medical and societal challenge, claiming millions of lives every year. Efforts to prevent SCD are hampered by imperfect risk prediction and inadequate solutions to specifically address arrhythmogenesis. Although resuscitation strategies have witnessed substantial evolution, there is a need to strengthen the organisation of community interventions and emergency medical systems across varied locations and health-care structures. With all the technological and medical advances of the 21st century, the fact that survival from sudden cardiac arrest (SCA) remains lower than 10% in most parts of the world is unacceptable. Recognising this urgent need, the Lancet Commission on SCD was constituted, bringing together 30 international experts in varied disciplines. Consistent progress in tackling SCD will require a completely revamped approach to SCD prevention, with wide-sweeping policy changes that will empower the development of both governmental and community-based programmes to maximise survival from SCA, and to comprehensively attend to survivors and decedents' families after the event. International collaborative efforts that maximally leverage and connect the expertise of various research organisations will need to be prioritised to properly address identified gaps. The Commission places substantial emphasis on the need to develop a multidisciplinary strategy that encompasses all aspects of SCD prevention and treatment. The Commission provides a critical assessment of the current scientific efforts in the field, and puts forth key recommendations to challenge, activate, and intensify efforts by both the scientific and global community with new directions, research, and innovation to reduce the burden of SCD worldwide.

Cardiac Genetic Investigation of Sudden Infant and Early Childhood Death: A Study From Victims to Families

Background Sudden infant death syndrome (SIDS) is the leading cause of death up to age 1. Sudden unexplained death in childhood (SUDC) is similar but affects mostly toddlers aged 1 to 4. SUDC is rarer than SIDS, and although cardiogenetic testing (molecular autopsy) identifies an underlying cause in a fraction of SIDS, less is known about SUDC. Methods and Results Seventy-seven SIDS and 16 SUDC cases underwent molecular autopsy with 25 definitive-evidence arrhythmia-associated genes. In 18 cases, another 76 genes with varying degrees of evidence were analyzed. Parents were offered cascade screening. Double-blind review of clinical-genetic data established genotype-phenotype correlations. The yield of likely pathogenic variants in the 25 genes was higher in SUDC than in SIDS (18.8% [3/16] versus 2.6% [2/77], respectively; P=0.03), whereas novel/ultra-rare variants of uncertain significance were comparably represented. Rare variants of uncertain significance and likely benign variants were found only in SIDS. In cases with expanded analyses, likely pathogenic/likely benign variants stemmed only from definitive-evidence genes, whereas all other genes contributed only variants of uncertain significance. Among 24 parents screened, variant status and phenotype largely agreed, and 3 cases positively correlated for cardiac channelopathies. Genotype-phenotype correlations significantly aided variant adjudication. Conclusions Genetic yield is higher in SUDC than in SIDS although, in both, it is contributed only by definitive-evidence genes. SIDS/SUDC cascade family screening facilitates establishment or dismissal of a diagnosis through definitive variant adjudication indicating that anonymity is no longer justifiable. Channelopathies may underlie a relevant fraction of SUDC. Binary classifications of genetic causality (pathogenic versus benign) could not always be adequate.

Prevention of Sudden Death and Management of Ventricular Arrhythmias in Arrhythmogenic Cardiomyopathy

Arrhythmogenic cardiomyopathy is an umbrella term for a group of inherited diseases of the cardiac muscle characterized by progressive fibro-fatty replacement of the myocardium. As suggested by the name, the disease confers electrical instability to the heart and increases the risk of the development of life-threatening arrhythmias, representing one of the leading causes of sudden cardiac death (SCD), especially in young athletes. In this review, the authors review the current knowledge of the disease, highlighting the state-of-the-art approaches to the prevention of the occurrence of SCD.

[Cardiac implantable electric devices in forensic medicine : Overview from the forensic and cardiology perspective]

In 2021, about 75,000 persons in Germany died unnaturally or due to unexplained reasons. As a consequence, there are difficulties in more precisely identifying the time, cause and circumstances of death. Nevertheless, clarification is crucial not only from the clinical perspective, but these data are of considerable importance in the context of investigative procedures as they can be used to answer numerous legally relevant questions. Cardiac implantable devices (CIED) are of vital importance in the treatment of cardiac arrhythmias. In 2020 about 100,000 patients underwent CIED implantation in Germany. Therefore, CIED are present in a relevant proportion of the deceased mentioned above. The valuable source of information represented by postmortal CIED interrogation has been shown in numerous studies. Nevertheless, postmortal CIED interrogation is not routinely performed in the context of forensic medical examinations for reasons of practicability. This article summarizes benefits and limitations of postmortal CIED interrogation from the perspective of forensic medicine and cardiology and gives a recommendation for realization.

Is Congenital Muscular Mitral-Aortic Discontinuity Another Feature of Obstructive Hypertrophic Cardiomyopathy? A Pathology Validation Study

Hypertrophic cardiomyopathy (HCM) is an inherited myocardial disease at risk of sudden cardiac death and heart failure, even requiring heart transplantation. A "muscular mitral-aortic discontinuity" has been reported during surgery in the obstructive form. We aimed to validate these findings through pathological analysis of HCM heart specimens from the cardiovascular pathology tissue registry. Hearts with septal asymmetric HCM from sudden cardiac death, other causes of death, or heart transplantation were included. Sex-matched and age-matched patients without HCM served as controls. Gross and histologic analysis of the mitral valve (MV) apparatus and the mitral-aortic continuity were performed. Thirty HCM hearts (median age, 29.5 years; 15 men) and 30 controls (median age, 30.5 years; 15 men) were studied. In HCM hearts, a septal bulging was present in 80%, an endocardial fibrous plaque in 63%, a thickening of the anterior MV leaflet in 56.7%, and an anomalous insertion of papillary muscle in 10%. All cases but 1 (97%) revealed a myocardial layer overlapping the mitral-aortic fibrous continuity on the posterior side, corresponding to the left atrial myocardium. A negative correlation between the length of this myocardial layer and the age and the anterior MV leaflet length was found. The length did not differ between HCM and controls. Pathologic study of obstructive HCM hearts does not confirm the existence of a "muscular mitral-aortic discontinuity". An extension of left atrial myocardium, overlapping posteriorly the intervalvular fibrosa, is rather visible, and its length decreases with age, possibly as a consequence of left atrial remodeling. Our study highlights the fundamental role of thorough gross examination and the value of organ retention for further analysis in order to validate new surgical and imaging findings.

Risk stratification of sudden cardiac death: a review

Sudden cardiac death (SCD) is responsible for several millions of deaths every year and remains a major health problem. To reduce this burden, diagnosing and identification of high-risk individuals and disease-specific risk stratification are essential. Treatment strategies include treatment of the underlying disease with lifestyle advice and drugs and decisions to implant a primary prevention implantable cardioverter-defibrillator (ICD) and perform ablation of the ventricles and novel treatment modalities such as left cardiac sympathetic denervation in rare specific primary electric diseases such as long QT syndrome and catecholaminergic polymorphic ventricular tachycardia. This review summarizes the current knowledge on SCD risk according to underlying heart disease and discusses the future of SCD prevention.

Sudden Cardiac Death in People With Schizophrenia: Higher Risk, Poorer Resuscitation Profiles, and Differing Pathologies

BACKGROUND

People with schizophrenia account for approximately 1.0% of the population and seem to experience increased rates of sudden cardiac death (SCD).

OBJECTIVES

This study sought to determine characteristics of increased SCD in people with schizophrenia.

METHODS

The End Unexplained Cardiac Death (EndUCD) prospective state-wide registry compared people aged 15 to 50 years with and without schizophrenia who experienced SCD within a 2-year time period and were referred for forensic evaluation.

RESULTS

We identified 579 individuals, of whom 65 (11.2%) had schizophrenia. Patients with schizophrenia were more commonly smokers (46.2% vs 23.0%; P < 0.0001), consumed excess alcohol (32.3% vs 21.4%; P = 0.05), and used QTc-prolonging medications (69.2% vs 17.9%; P < 0.0001). They were less likely to arrest while exercising (0.0% vs 6.4%; P = 0.04). Unfavorable arrest-related factors included lower rates of witnessed arrest (6.2% vs 23.5%; P < 0.0001), more likely to be found in asystole (92.3% vs 73.3%; P < 0.0001), and being more likely to be found as part of a welfare check after a prolonged period of time (median 42 hours vs 12 hours; P = 0.003). There was more frequent evidence of decomposition, and they more commonly underwent autopsy (41.2% vs 26.4%; P = 0.04 and 93.8% vs 82.5%; P = 0.05), with a diagnosis of nonischemic cardiomyopathy being more common (29.2% vs 18.1%; P = 0.04).

CONCLUSIONS

People with schizophrenia account for 11% of young SCD patients referred for forensic investigations, exceeding population rates by 11-fold. They have a higher preexisting cardiac risk factor burden, unfavorable resuscitation profiles, and higher rates of nonischemic cardiomyopathy. Strategies targeting biopsychosocial support may deliver not only psychological benefits, but also help to decrease unwitnessed cardiac arrest.

A fatal mono-intoxication with 4-fluoroisobutyrylfentanyl: Case report with postmortem concentrations

We report on a case of a 35-year-old man who died suddenly and unexpectedly due to a 4-fluoroisobutyrylfentanyl (4-FIBF) mono-intoxication. Pathological, toxicological and chemical investigations were conducted at the Netherlands Forensic Institute. A full three-cavity forensic pathological examination was performed according to international guidelines. Biological samples obtained during autopsy were comprehensively investigated for the presence of toxic substances using headspace gas chromatography (GC) with flame ionization detection, liquid chromatography-time-of-flight mass spectrometry (LC-TOF-MS), GC-MS, high-performance LC with diode array detection and LC-tandem MS (LC-MS-MS). The seized crystalline substance found next to the body was investigated using a presumptive color test, GC-MS, Fourier-transform infrared spectroscopy and nuclear magnetic resonance. Pathological investigation identified minor lymphocytic infiltrates in the heart, considered irrelevant for the cause of death. Toxicological analysis of the victims' blood indicated the presence of a fluorobutyrylfentanyl (FBF) isomer, with no other compounds detected. The FBF isomer was identified in the seized crystalline substance as 4-FIBF. 4-FIBF concentrations were quantified in femoral blood (0.030 mg/L), heart blood (0.12 mg/L), vitreous humor (0.067 mg/L), brain tissue (>0.081 mg/kg), liver tissue (0.44 mg/kg) and urine (approximately 0.01 mg/L). Based on the outcomes of the pathological, toxicological and chemical investigations, the cause of death of the deceased was attributed to a fatal 4-FIBF mono-intoxication. The presented case underlines the added value of a combined bioanalytical and chemical investigative approach to identify and subsequently quantify fentanyl isomers in postmortem cases. Furthermore, it demonstrates the importance of investigating the postmortem redistribution of novel fentanyl analogs to establish reference values and to subsequently allow for correct interpretation of cause of death analysis in future casework.

Increased Epicardial Adipose Tissue and Heart Characteristics Are Correlated with BMI and Predict Silent Myocardial Infarction in Sudden Cardiac Death Subjects: An Autopsy Study

BACKGROUND

Sudden cardiac death (SCD) is a significant global public health issue and the leading cause of death worldwide. Its etiopathogenesis is complex and multilayered, involving dynamic factors interacting with a preexistent cardiovascular pathology, frequently unknown, and resulting in cardiac rhythm disorders and cardiac arrest; Methods: This study conducted a retrospective descriptive analysis over a one-year period, identifying 321 autopsy cases of sudden deaths from the Institute of Legal Medicine in Mures County, Romania, in 2019. From the 321 sudden death cases, 189 autopsy reports were selected for analysis based on inclusion and exclusion; Results: The autopsies had a mean age of 61.16 years and included 140 males and 49 females. No significant differences were found between the silent myocardial infarction (SMI) and no-SMI groups regarding demographic data. The SMI group exhibited higher thickness of LV (left ventricle), IV (interventricular septum), EAT LCx (epicardial adipose tissue at left circumflex artery), EAT LAD (epicardial adipose tissue at left anterior descending artery), heart weight, and BMI (body mass index). The left coronary artery showed a higher incidence of type V plaques, while the right coronary artery showed higher incidences of type V and type VI plaque. The SMI group also exhibited a higher incidence of moderate and severe valvular atherosclerosis, severe left ventricle dilatation, and a lower incidence of mild left ventricle dilatation. In addition, the SMI group showed a higher presence of contraction band necrosis on histological examination. Multivariate analysis revealed that type V and type VI plaques for the right and left coronary arteries, moderate and severe valvular atherosclerosis, severe left ventricle dilatation, heart weight, EAT LCx, EAT LAD, LV thickness, IV thickness, BMI, and the presence of contraction band necrosis are all independent predictors of SMI; Conclusions: The findings suggest that SCD is a complex condition, and its etiopathogenesis involves dynamic factors interacting with pre-existing cardiovascular pathology. The risk factors of SCD are similar to those of ischemic heart disease. The findings of this study could guide clinicians in identifying patients at risk of SCD and implementing preventive measures.

A Genome-Wide Analysis of a Sudden Cardiac Death Cohort: Identifying Novel Target Variants in the Era of Molecular Autopsy

Sudden cardiac death (SCD) is an unexpected natural death due to cardiac causes, usually happening within one hour of symptom manifestation or in individuals in good health up to 24 h before the event. Genomic screening has been increasingly applied as a useful approach to detecting the genetic variants that potentially contribute to SCD and helping the evaluation of SCD cases in the post-mortem setting. Our aim was to identify the genetic markers associated with SCD, which might enable its target screening and prevention. In this scope, a case-control analysis through the post-mortem genome-wide screening of 30 autopsy cases was performed. We identified a high number of novel genetic variants associated with SCD, of which 25 polymorphisms were consistent with a previous link to cardiovascular diseases. We ascertained that many genes have been already linked to cardiovascular system functioning and diseases and that the metabolisms most implicated in SCD are the lipid, cholesterol, arachidonic acid, and drug metabolisms, suggesting their roles as potential risk factors. Overall, the genetic variants pinpointed herein might be useful markers of SCD, but the novelty of these results requires further investigations.

Autopsy and sudden death

Our story dates back in the late 70s, when a series of juvenile sudden death (SD) occurred in the Veneto region, north east of Italy. A successful application for a prospective study on young people dying suddenly (<35-year-old, sudden infant death syndrome excluded) was submitted to the regional health authorities, thus implementing a network of collaboration with local anatomic and forensic pathologists, to collect all such events and to gather demographic data. The project is still in progress, and since then, we studied hundreds of consecutive juvenile SD cases, allowing to identify the culprit diseases in the various organs and cardiac structures (aorta, coronary arteries, myocardium, valves, and conduction system). The long-standing Veneto region experience clearly shows that autopsy still plays a pivotal role in the study and prevention of SD and should be carried out regularly. With time, the investigation of SD moved from the classic post-mortem study to molecular autopsy, especially in cases of SD with structurally normal heart. Sudden death prevention in the young has to be faced by an interdisciplinary team, including pathologists, cardiologists, sport physicians, and geneticists, the clinicopathologic correlation method still being the polar star. The game in the fight against SD is still played in the anatomical theatre, the place where 'death enjoys to save lives'.

Galectin-3 Is Associated with Cardiac Fibrosis and an Increased Risk of Sudden Death

BACKGROUND

Myocardial fibrosis is a common postmortem finding among individuals with Sudden Cardiac Death (SCD). Numerous in vivo and in vitro studies have shown that increased galectin-3 (gal3) expression into the myocardium is associated with higher incidence of fibrosis. Although elevated gal3 expression is linked with myocardial fibrosis, its role in predicting the risk of SCD is unknown.

METHODS

We reviewed the clinical datasets and post-mortem examination of 221 subjects who had died suddenly. We examined myocardial pathology including the extent of cardiac hypertrophy, fibrosis, and the degree of coronary atherosclerosis in these subjects. In a select group of SCD subjects, we studied myocardial gal3 and periostin expression using immunohistochemistry. To further examine if a higher level of circulating gal3 can be detected preceding sudden death, we measured serum gal3 in a porcine model of subtotal coronary artery ligation which shows an increased tendency to develop lethal cardiac arrhythmias, including ventricular tachycardia or fibrillation.

RESULTS

Of the total 1314 human subjects screened, 12.7% had SCD. Comparison of age-matched SCD with non-SCD subjects showed that SCD groups had excessive myocardial fibrosis involving both the left ventricular free wall and interventricular septum. In pigs with subtotal coronary artery ligation and SCD, we detected significantly elevated circulating gal3 levels approximately 10 days preceding the SCD event. Immunohistochemistry showed increased myocardial gal3 and periostin expression in pigs that died suddenly, compared to the controls.

CONCLUSION

Our study shows that increased gal3 is associated with a higher risk of myocardial fibrosis and the risk of SCD. This supports the importance of larger translational studies to target gal3 to prevent cardiac fibrosis and attenuate the risk of SCD.

Exertional-Related Sudden Cardiac Death in a Young, Presumed Healthy, and Medically Screened Population: A Military Case Series

ABSTRACT

Sudden cardiac death (SCD) is defined as death from cardiac causes with loss of consciousness occurring within 1 hour of a change in cardiovascular status. As subset, SCD associated with physical exertion (SCD/E) can be defined as a cardiac event whose symptoms start during or within 1 hour of physical exertion. The US military represents a unique opportunity for studying SCD/E because of medical screening at recruitment, mandatory physical training, an active surveillance system, and centralized autopsy services. Because of medical screening, recruits are presumed healthy, but significant conditions can go undetected. We present 4 diverse cases of SCD/E in the military setting. Sudden cardiac death associated with physical exertion is often the first indication of a serious occult cardiac pathology. Postmortem genetic testing revealed a causative pathogenic mutation in 1 of 4 cases, enabling genetic testing of family members to prevent similar catastrophic loss of life, underscoring the importance of postmortem evaluation including genetic testing. Further investigations will help direct screening and prevention to capture those at risk for SCD. The cases presented in this series are a sample of the diverse etiologies and contexts surrounding SCD/E in the military setting that have been captured by Armed Forces Medical Examiner System.

[Circadian and septadian variation in sudden cardiac death : Autopsy registry of the Tunisian North]

INTRODUCTION

Several studies have suggested a circadian and septadian pattern of incidence of sudden cardiac death with a morning peak and a Monday peak.

OBJECTIVE

To analyze the circadian and septadian pattern of occurrence of sudden cardiac death in the eight northern Tunisian governorates.

METHODS

We prospectively collected epidemiological and autopsy data of sudden cardiac death victims occurring in the northern region of Tunisia between January 2013 and December 2019.

RESULTS

The population included 1834 men (79.6%) and 468 women (20.4%) with a mean age of 56.5 ± 14 years. Smoking (53.9%) was the most prevalent cardiovascular risk factor. One-fifth (20.9%) of victims had known heart disease, and 3% had a family history of sudden death. ischemic heart disease was the leading cause of sudden death (46.8% of cases). One- fourth (25.7%) of autopsies were negative. Analysis of the circadian pattern of occurrence of sudden cardiac death identified a peak (36.1%, p < 0.001) between midnight and 6 am. This nocturnal excess mortality was significant (p < 0.001) and independent of sex (34.1 % in men and 43.8 % in women) and cause of death (39.3 % of cases of sudden ischemic death and 33.3 % of cases of nonischemic death). Moreover, there was a significant septadian variability in the occurrence of sudden death (p: 0.0015), with a peak on Friday (15.8 %, p: 0.042).

CONCLUSION

This study showed a peak of sudden death between midnight and 6 am, and on Fridays, confirming the modification of the classic circadian and septadian pattern of sudden death occurrence. These results may help optimize the deployment of emergency mobile teams and structures during the most vulnerable periods.

Cardiac rupture during acute myocardial infarction : Autopsy study (2004-2020)

INTRODUCTION

Cardiac rupture is a rare but critical complication of myocardial infarction with an incidence of 1 to 3% of cases. We aimed in this autopsy study to analyze the anatomical, epidemiological, cardiac, and coronary profiles of cardiac rupture in the Monastir region.

METHODS

We conducted a descriptive study with retrospective data collection of all cases of myocardial infarction complicated by a cardiac rupture over seventeen years (2004-2020).

RESULTS

Thirty-one cases were included in this study. The mean age of the cases was 67 years with a male predominance. Sixteen cases (57%) had cardiovascular risk factors. The most common symptomatology reported before death was acute chest pain in 57% of cases. Fourteen cases (45%) corresponded to the definition of sudden cardiac death. At autopsy, the heart had a mean weight of 452.78 grams. A large hemopericardium was associated in 90% of cases. Myocardial rupture involved the posterior wall of the left ventricle in 50% of cases. The myocardial rupture occurred at a site of acute myocardial infarction in 86% of cases and on a myocardial scar in 14% of cases. The coronary study showed double or triple vessel atherosclerotic coronary artery disease in 57% of cases with fresh thrombi at the infarct-related coronary in 11% of cases.

CONCLUSIONS

Our analysis found that cardiac rupture mostly involved elderly subjects with underlying cardiovascular risk factors. Our findings sustain that age is a determining prognostic factor after acute coronary syndrome with the need for further education and awareness-raising efforts to speed up access to care for these patients.

Causes of sudden death

Sudden cardiac death (SCD) pathophysiological point of view can be either mechanical or electrical. In case of mechanical SCD, the most frequent causes are pulmonary thromboembolism and cardiac tamponade due to intrapericardial rupture (aortic dissection, heart rupture). This distinction is important because cardiac arrest retains survival potential through cardiopulmonary resuscitation and defibrillators only if the rhythm is shockable. The heart diseases that can cause SCD vary according to the age of the individual. In young people, primary electrical diseases ('ion channel diseases') and cardiomyopathies (particularly hypertrophic and arrhythmogenic), both genetically determined and therefore potentially recurred in the proband's family, as well as myocarditis and coronary anomalies prevail; in adult-elderly populations, coronary atherosclerosis with its complications and degenerative valve diseases (aortic stenosis and mitral valve prolapse) predominate. In this short text, the main structural heart diseases characterized by electrical instability at risk of SCD will be recalled, with a focus on coronary, myocardial, and valvular diseases.

Sudden Cardiac Death Among Adolescents in the United Kingdom

BACKGROUND

Causes and precipitating factors of sudden cardiac death (SCD) in adolescents are poorly understood.

OBJECTIVES

The authors sought to investigate the etiologies of SCD and their association with physical activity in a large cohort of adolescents.

METHODS

Between 1994 and June 2022, 7,675 cases of SCD were consecutively referred to our national cardiac pathology center; 756 (10%) were adolescents. All cases underwent detailed autopsy evaluation by expert cardiac pathologists. Clinical information was obtained from referring coroners.

RESULTS

A structurally normal heart, indicative of sudden arrhythmic death syndrome was the most common autopsy finding (n = 474; 63%). Myocardial diseases were detected in 163 cases (22%), including arrhythmogenic cardiomyopathy (n = 36; 5%), hypertrophic cardiomyopathy (n = 31; 4%), idiopathic left ventricular hypertrophy (n = 31; 4%), and myocarditis (n = 30; 4%). Coronary artery anomalies were identified in 17 cases (2%). Decedents were competitive athletes in 128 cases (17%), and 159 decedents (21%) died during exercise. Arrhythmogenic cardiomyopathy was diagnosed in 8% of athletes compared with 4% of nonathletes (P = 0.05); coronary artery anomalies were significantly more common in athletes (9% vs 1%; P < 0.001), as well as commotio cordis (5% compared with 1% in nonathletes; P = 0.001). The 3 main comorbidities were asthma (n = 58; 8%), epilepsy (n = 44; 6%), and obesity (n = 40; 5%).

CONCLUSIONS

Sudden arrhythmic death syndrome and myocardial diseases are the most common conditions diagnosed at autopsy in adolescent victims of SCD. Among causes of SCD, arrhythmogenic cardiomyopathy, coronary artery anomalies, and commotio cordis are more common in young athletes than in similar age sedentary individuals.

Genetically determined cardiomyopathies at autopsy: the pivotal role of the pathologist in establishing the diagnosis and guiding family screening

Cardiomyopathies (CMP) comprise a heterogenous group of diseases affecting primarily the myocardium, either genetic and/or acquired in origin. While many classification systems have been proposed in the clinical setting, there is no internationally agreed pathological consensus concerning the diagnostic approach to inherited CMP at autopsy. A document on autopsy diagnosis of CMP is needed because the complexity of the pathologic backgrounds requires proper insight and expertise. In cases presenting with cardiac hypertrophy and/or dilatation/scarring with normal coronary arteries, a suspicion of inherited CMP must be considered, and a histological examination is essential. Establishing the actual cause of the disease may require a number of tissue-based and/or fluid-based investigations, be it histological, ultrastructural, or molecular. A history of illicit drug use must be looked for. Sudden death is frequently the first manifestation of disease in case of CMP, especially in the young. Also, during routine clinical or forensic autopsies, a suspicion of CMP may arise based on clinical data or pathological findings at autopsy. It is thus a challenge to make a diagnosis of a CMP at autopsy. The pathology report should provide the relevant data and a cardiac diagnosis which can help the family in furthering investigations, including genetic testing in case of genetic forms of CMP. With the explosion in molecular testing and the concept of the molecular autopsy, the pathologist should use strict criteria in the diagnosis of CMP, and helpful for clinical geneticists and cardiologists who advise the family as to the possibility of a genetic disease.

Systematic dissection, preservation, and multiomics in whole human and bovine hearts

OBJECTIVES

We sought to develop a rigorous, systematic protocol for the dissection and preservation of human hearts for biobanking that expands previous success in postmortem transcriptomics to multiomics from paired tissue.

BACKGROUND

Existing cardiac biobanks consist largely of biopsy tissue or explanted hearts in select diseases and are insufficient for correlating whole organ phenotype with clinical data.

METHODS

We demonstrate optimal conditions for multiomics interrogation (ribonucleic acid (RNA) sequencing, untargeted metabolomics) in hearts by evaluating the effect of technical variables (storage solution, temperature) and simulated postmortem interval (PMI) on RNA and metabolite stability. We used bovine (n=3) and human (n=2) hearts fixed in PAXgene or snap-frozen with liquid nitrogen.

RESULTS

Using a paired Wald test, only two of the genes assessed were differentially expressed between left ventricular samples from bovine hearts stored in PAXgene at 0 and 12 hours PMI (FDR q<0.05). We obtained similar findings in human left ventricular samples, suggesting stability of RNA transcripts at PMIs up to 12 hours. Different library preparation methods (mRNA poly-A capture vs. rRNA depletion) resulted in similar quality metrics with both library preparations achieving >95% of reads properly aligning to the reference genomes across all PMIs for bovine and human hearts. PMI had no effect on RNA Integrity Number or quantity of RNA recovered at the time points evaluated. Of the metabolites identified (855 total) using untargeted metabolomics of human left ventricular tissue, 503 metabolites remained stable across PMIs (0, 4, 8, 12 hours). Most metabolic pathways retained several stable metabolites.

CONCLUSIONS

Our data demonstrate a technically rigorous, reproducible protocol that will enhance cardiac biobanking practices and facilitate novel insights into human CVD.

CONDENSED ABSTRACT

Cardiovascular disease (CVD) is the leading cause of mortality worldwide. Current biobanking practices insufficiently capture both the diverse array of phenotypes present in CVDs and the spatial heterogeneity across cardiac tissue sites. We have developed a rigorous and systematic protocol for the dissection and preservation of human cardiac biospecimens to enhance the availability of whole organ tissue for multiple applications. When combined with longitudinal clinical phenotyping, our protocol will enable multiomics in hearts to deepen our understanding of CVDs.

Sudden cardiac death related to left coronary artery anomalies including hypoplasia and anomalous origin with retro-aortic course

Congenital anomalies of the coronary arteries are a rare condition with an incidence of 0.3-1.3% in the general population. Clinically, sometimes these anomalies increase the risk of myocardial ischemia, which can present with a wide spectrum of symptoms, from angina to sudden cardiac death (SCD). This case report is about the SCD of an 8-year-old male, in apparent good health, during a football training. Although basic life support maneuvers were performed timely from bystanders and medical staff, the automated external defibrillator (AED) was not used. Autopsy revealed multiple left coronary artery (LCA) anomalies: origin from a separate ostium in the right sinus of Valsalva, slit-like shape of the ostium, acute angle take-off of the LCA from the aorta, retro-aortic course and focal coronary hypoplasia of some branches of the LCA. Microscopic examination revealed diffuse ischemic consequences at a different stage of tissue repair and mild multifocal lymphocytic infiltration. No other significant elements were detected at post-mortem examination. We discuss the forensic evaluation about the cause and the manner of death, considering also the modality of the resuscitation attempts and the claimed malpractice, as often occurs in case of sudden unexpected death in young athletes.

Significance of postmortem biomarkers and multimarker strategy in sudden cardiac death

The most common cause in the etiology of sudden cardiac death (SCD) is ischemic heart disease due to atherosclerosis. Postmortem diagnosis can be made by histopathological examinations, but routine histopathological examinations are limited, especially in the early period of postmortem ischemia. For this reason, many methods are being investigated for the postmortem diagnosis of ischemia, and postmortem biochemical studies are promising. In our study, we evaluated the biochemical markers; hs-cTnT, NT-proBNP, H-FABP, pentraxin-3, copeptin, ischemic modified albumin (IMA), and PAPP-A in postmortem serums. In forensic pathology practice, it was investigated whether it would be useful to go to the diagnosis by measuring more than one marker in a single biological fluid in SCD cases. The study included 35 sudden cardiac death cases and 24 control cases and as a result of our study, hs-cTnT, NT-proBNP, and H-FABP values were found to be significantly higher in the SCD group than in the control group. Within the scope of the multi-marker strategy, models were tried to be developed in which the markers were used together, and it was concluded that the model consisting of the myocardial ischemia marker hs-cTnT, the myocardial stress marker NT-proBNP, and the inflammation marker pentraxin 3 was the most accurate combination by correctly classifying the cases at a rate of 94.9%. As a result, it was thought that it would be appropriate to use the multi-marker strategy which is widely used in clinical applications, also in forensic medicine applications.

Sudden cardiac death in the young: A consensus statement on recommended practices for cardiac examination by pathologists from the Society for Cardiovascular Pathology

Sudden cardiac death is, by definition, an unexpected, untimely death caused by a cardiac condition in a person with known or unknown heart disease. This major international public health problem accounts for approximately 15-20% of all deaths. Typically more common in older adults with acquired heart disease, SCD also can occur in the young where the cause is more likely to be a genetically transmitted process. As these inherited disease processes can affect multiple family members, it is critical that these deaths are appropriately and thoroughly investigated. Across the United States, SCD cases in those less than 40 years of age will often fall under medical examiner/coroner jurisdiction resulting in scene investigation, review of available medical records and a complete autopsy including toxicological and histological studies. To date, there have not been consistent or uniform guidelines for cardiac examination in these cases. In addition, many medical examiner/coroner offices are understaffed and/or underfunded, both of which may hamper specialized examinations or studies (e.g., molecular testing). Use of such guidelines by pathologists in cases of SCD in decedents aged 1-39 years of age could result in life-saving medical intervention for other family members. These recommendations also may provide support for underfunded offices to argue for the significance of this specialized testing. As cardiac examinations in the setting of SCD in the young fall under ME/C jurisdiction, this consensus paper has been developed with members of the Society of Cardiovascular Pathology working with cardiovascular pathology-trained, practicing forensic pathologists.

Risk factors of sudden cardiac death in women: A 10 years study in Tunisia

BACKGROUND

Sudden cardiac death (SCD) represents a frequent etiology of sudden death. It represents a major public health issue. Few data about SCD in women are available from the Arab world. Our work aimed to analyze the risk factors of sudden cardiac death in Tunisian women in comparison with men.

METHODS

A cross-sectional retrospective study including all sudden cardiac death cases, conducted in the Forensic Medicine Department of the main teaching hospital of Tunis, between January 2010 and December 2019.

RESULTS

We counted 417 cases of sudden cardiac death in women representing 17.5% of the total number of sudden cardiac deaths recorded during the study period. The average age was 60.03 ± 15.01 years with a predominance of urban married women. The most frequent cardiac risk factors were high blood pressure (50%), diabetes (36.2%), and cardiac disease history (34.2%). Predominately married women with a history of High blood pressure and diabetes, had a high predictive of sudden cardiac death.

CONCLUSION

Cardiac sudden death is no longer a male focused issue. As a matter of facts Rates of SCD in women are rising with a different pattern. We will highlight the importance of adopting specific preventive measures of SCD in female.

The Role of the Bicuspid Aortic Valve in Sudden Cardiac Death - Findings at Cardiac Autopsy

BACKGROUND

Bicuspid aortic valve (BAV) is the most common congenital cardiac defect in the adult population, with a prevalence of 0.5-2%. It is well recognised that aortic stenosis (AS), aortic regurgitation (AR) and aortopathy may develop by the fifth or sixth decade of life. There is a paucity of autopsy studies evaluating the hearts of subjects with BAV. The aim of this study is to help to ascertain the role of the bicuspid valve in the cause of sudden cardiac deaths.

METHODS

A database of 6325 whole hearts referred to a specialist cardiac pathology centre between 2004 and 2021 was reviewed to identify a subgroup of 91 subjects with a BAV reported. All cases had a negative full body autopsy and toxicology before being referred and subsequently underwent detailed cardiac evaluation including histological analysis by expert cardiac pathologists.

RESULTS

The mean age of death was 37±16 years (84% male). Death was attributed to aortic valve or aortic disease in 57% (n=52) of cases; AS 30% (n= 27), endocarditis 11% (n=10), aortic dissection (AD) 9% (n=8) and AR 8% (n=7). In the remaining 43% of cases, BAV was an incidental finding.

CONCLUSION

The majority of deaths in young individuals with BAV were attributed to complications related to the aortic valve or aorta indicating that BAV is not a benign condition. When a BAV is identified, individuals should be appropriately follow-up with imaging to inform the optimal timing of intervention before a complication develops that may predispose the individual to a premature death.

Sudden cardiac death in synucleinopathies

The purpose of this study was to investigate the cause of death in subjects with α-synucleinopathies (ASs) and the confirmed presence of cardiac α-synuclein (α-syn), compared to non-AS disorders in a neuropathologically confirmed cohort. In total, 78 neuropathologically confirmed AS cases positive for cardiac α-syn were included in the study. Individuals with other neurocognitive diseases, having no α-syn in the brainstem or above, nor in cardiac nerves, served as controls (n = 53). Data regarding the cause of death, cardiac α-syn, pathological cardiac findings, and cardio- and cerebrovascular disease were assembled from autopsy reports and medical records. In the AS group, there was a significantly higher prevalence of sudden cardiac death ([SCD]; n = 40, 51.3%) compared to the control group (n = 12, 22.6%, p < 0.001). No statistically significant differences between the groups were reported regarding other cardiac conditions on autopsy or regarding cardio- and cerebrovascular disease from the medical records. The most prevalent cause of death in the AS group was SCD, which differed significantly from the control group. This suggests that α-syn deposits in cardiac nerves may cause lethal alterations in cardiac function, warranting further research.

Sudden arrhythmic death and cardiomyopathy are important causes of sudden cardiac death in the UK: results from a national coronial autopsy database

AIMS

Sudden cardiac death (SCD) is defined as natural unexpected death in witnessed cases occurring < 1 h and in unwitnessed cases as last seen alive < 24 h. SCD due to ischaemic heart disease (IHD) is frequent in older age groups; in younger people genetic cardiac causes, including channelopathies and cardiomyopathies, are more frequent. This study aimed to present the causes of SCD from a large specialist pathology registry.

METHODS AND RESULTS

Cases were examined macroscopically and microscopically by two expert cardiac pathologists. The hearts from 7214 SCD cases were examined between 1994 and 2021. Sudden arrhythmic death syndrome (SADS), a morphologically normal heart, which can be underlaid by cardiac channelopathies, is most common (3821, 53%) followed by the cardiomyopathies (1558, 22%), then IHD (670, 9%), valve disease (225, 3%), congenital heart disease (213, 3%) and myocarditis/sarcoidosis (206, 3%). Hypertensive heart disease (185, 3%), aortic disease (129, 2%), vascular disease (97, 1%) and conduction disease (40, 1%) occur in smaller proportions.

DISCUSSION

To our knowledge, this is the largest SCD cohort with autopsy findings ever reported from one country. SADS and cardiomyopathies predominate. This study highlights the importance of the autopsy in SCD, which is a significant public health concern in all age groups. Knowing the true incidence in our population will improve risk stratification and develop preventative strategies for family members. There is now a national pilot study integrating molecular autopsy and family screening into the assessment of SCD victims.

Molecular autopsy: Twenty years of post-mortem diagnosis in sudden cardiac death

In the forensic medicine field, molecular autopsy is the post-mortem genetic analysis performed to attempt to unravel the cause of decease in cases remaining unexplained after a comprehensive forensic autopsy. This negative autopsy, classified as negative or non-conclusive, usually occurs in young population. In these cases, in which the cause of death is unascertained after a thorough autopsy, an underlying inherited arrhythmogenic syndrome is the main suspected cause of death. Next-generation sequencing allows a rapid and cost-effectives genetic analysis, identifying a rare variant classified as potentially pathogenic in up to 25% of sudden death cases in young population. The first symptom of an inherited arrhythmogenic disease may be a malignant arrhythmia, and even sudden death. Early identification of a pathogenic genetic alteration associated with an inherited arrhythmogenic syndrome may help to adopt preventive personalized measures to reduce risk of malignant arrhythmias and sudden death in the victim's relatives, at risk despite being asymptomatic. The current main challenge is a proper genetic interpretation of variants identified and useful clinical translation. The implications of this personalized translational medicine are multifaceted, requiring the dedication of a specialized team, including forensic scientists, pathologists, cardiologists, pediatric cardiologists, and geneticists.

Sudden Cardiac Death in Athletes: Facts and Fallacies

The benefits of exercise for cardiovascular and general health are many. However, sudden cardiac death (SCD) may occur in apparently healthy athletes who perform at the highest levels. A diverse spectrum of diseases is implicated in SCD in athletes, and while atherosclerotic coronary artery disease predominates in individuals of >35 years of age, primary cardiomyopathies and ion channelopathies are prevalent in young individuals. Prevention of SCD in athletes relies on the implementation of health policies aimed at the early identification of arrhythmogenic diseases (such as cardiac screening) and successful resuscitation (such as widespread utilization of automatic external defibrillators and training members of the public on cardiopulmonary resuscitation). This review will focus on the epidemiology and aetiologies of SCD in athletes, and examine fallacies in the approach to this controversial field. Furthermore, potential strategies to prevent these tragic events will be discussed, analysing current practice, gaps in knowledge and future directions.

Comparison of Cardiovascular Pathology In Animal Models of SARS-CoV-2 Infection: Recommendations Regarding Standardization of Research Methods

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged as the viral pathogen that led to the global COVID-19 pandemic that began in late 2019. Because SARS-CoV-2 primarily causes a respiratory disease, much research conducted to date has focused on the respiratory system. However, SARS-CoV-2 infection also affects other organ systems, including the cardiovascular system. In this critical analysis of published data, we evaluate the evidence of cardiovascular pathology in human patients and animals. Overall, we find that the presence or absence of cardiovascular pathology is reported infrequently in both human autopsy studies and animal models of SARS-CoV-2 infection. Moreover, in those studies that have reported cardiovascular pathology, we identified issues in their design and execution that reduce confidence in the conclusions regarding SARS-CoV-2 infection as a cause of significant cardiovascular pathology. Throughout this overview, we expand on these limitations and provide recommendations to ensure a high level of scientific rigor and reproducibility.

Application of postmortem imaging modalities in cases of sudden death due to cardiovascular diseases-current achievements and limitations from a pathology perspective : Endorsed by the Association for European Cardiovascular Pathology and by the International Society of Forensic Radiology and Imaging

Postmortem imaging (PMI) is increasingly used in postmortem practice and is considered a potential alternative to a conventional autopsy, particularly in case of sudden cardiac deaths (SCD). In 2017, the Association for European Cardiovascular Pathology (AECVP) published guidelines on how to perform an autopsy in such cases, which is still considered the gold standard, but the diagnostic value of PMI herein was not analyzed in detail. At present, significant progress has been made in the PMI diagnosis of acute ischemic heart disease, the most important cause of SCD, while the introduction of postmortem CT angiography (PMCTA) has improved the visualization of several parameters of coronary artery pathology that can support a diagnosis of SCD. Postmortem magnetic resonance (PMMR) allows the detection of acute myocardial injury-related edema. However, PMI has limitations when compared to clinical imaging, which severely impacts the postmortem diagnosis of myocardial injuries (ischemic versus non-ischemic), the age-dating of coronary occlusion (acute versus old), other potentially SCD-related cardiac lesions (e.g., the distinctive morphologies of cardiomyopathies), aortic diseases underlying dissection or rupture, or pulmonary embolism. In these instances, PMI cannot replace a histopathological examination for a final diagnosis. Emerging minimally invasive techniques at PMI such as image-guided biopsies of the myocardium or the aorta, provide promising results that warrant further investigations. The rapid developments in the field of postmortem imaging imply that the diagnosis of sudden death due to cardiovascular diseases will soon require detailed knowledge of both postmortem radiology and of pathology.

Molecular autopsy in sudden cardiac death

A post-mortem genetic analysis in the process of investigating a sudden death episode is known as 'molecular autopsy'. It is usually performed in cases without a conclusive cause of death and after a comprehensive medico-legal autopsy. In these sudden unexplained death cases, an underlying inherited arrhythmogenic cardiac disease is the main suspected cause of death. The objective is to unravel a genetic diagnosis of the victim, but it also enables cascade genetic screening of the victim's relatives. Early identification of a deleterious genetic alteration associated with an inherited arrhythmogenic disease may help to adopt preventive personalized measures to reduce risk of malignant arrhythmias and sudden death. It is important to remark that the first symptom of an inherited arrhythmogenic cardiac disease may the malignant arrhythmia and even sudden death. Next-generation sequencing allows a rapid and cost-effectives genetic analysis. Close interaction between the forensic scientist, pathologist, cardiologist, pediatric cardiologist and geneticist has allowed a progressive increase of genetic yield in recent years, identifying the pathogenic genetic alteration. However, large numbers of rare genetic alterations remain classified as having an ambiguous role, impeding a proper genetic interpretation and useful translation into both forensic and cardiological arena.

Juvenile sudden cardiac death due to congenital coronary ostial valve-like ridges: A case report and literature review

Coronary artery anomalies are a heterogeneous group of congenital disorders affecting the coronary pattern with a characteristic (origin, number, number of hosts, course, etc.). They are rarely found in the population. We report the case of a 21-year-old male who died from sudden cardiac death caused by an isolated coronary ostial obstruction, secondary to a rare anomaly, the presence of a valve-like ridge consisting of a small fold in the Valsalva aortic sinus. The study provides a brief literature review on the pathophysiology, diagnosis, and clinical and medico-legal issues in coronary artery anomaly cases that may be helpful in forensic practice when dealing with sudden cardiac death in young people and highlights key points for further research and public health measures.

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.