Is there progress in the autopsy diagnosis of sudden unexpected death in adults?

Sudden death is now currently described as natural unexpected death occurring within 1h of new symptoms. Most studies on the subject focused on cardiac causes of death because most of the cases are related to cardiovascular disease, especially coronary artery disease. The incidence of sudden death varies largely as a function of coronary heart disease prevalence and is underestimated. Although cardiac causes are the leading cause of sudden death, the exact incidence of the other causes is not well established because in some countries, many sudden deaths are not autopsied. Many risk factors of sudden cardiac death are identified: age, gender, heredity factors such as malignant mutations, left ventricular hypertrophy and left ventricle function impairment. The role of the police surgeon in the investigation of sudden death is very important. This investigation requires the interrogation of witnesses and of the family members of the deceased. The interrogation of physicians of the rescue team who attempted resuscitation is also useful. Recent symptoms before death and past medical history must be searched. Other sudden deaths in the family must be noted. The distinction between sudden death at rest and during effort is very important because some lethal arrhythmia are triggered by catecholamines during stressful activity. The type of drugs taken by the deceased may indicate a particular disease linked with sudden death. Sudden death in the young always requires systematic forensic autopsy performed by at least one forensic pathologist. According to recent autopsy studies, coronary artery disease is still the major cause of death in people aged more than 35 years. Cardiomyopathies are more frequently encountered in people aged less than 35 years. The most frequent cardiomyopathy revealed by sudden death is now arrhythmogenic right ventricular cardiomyopathy also known simply as right ventricular cardiomyopathy (RVC). The postmortem diagnosis of cardiomyopathies is very important because the family of the deceased will need counseling and the first-degree relatives may undergo a possible screening to prevent other sudden deaths. In each case of sudden death, one important duty of the forensic pathologist is to inform the family of all autopsy results within 1 month after the autopsy. Most of the recent progress in autopsy diagnosis of sudden unexpected death in the adults comes from molecular biology, especially in case of sudden death without significant morphological anomalies. Searching mutations linked with functional cardiac pathology such as long-QT syndrome, Brugada syndrome or idiopathic ventricular fibrillation is now the best way in order to explain such sudden death. Moreover, new syndromes have been described by cardiologists, such as short-QT syndrome and revealed in some cases by a sudden death. Molecular biology is now needed when limits of morphological diagnosis have been reached.     

Causes of Sudden Death in Patients with Obstructive Sleep Apnea

There are few autopsy studies of patients dying suddenly with obstructive sleep apnea (OSA). Twenty‐five forensic autopsies of unexpected sudden death in individuals with OSA were reviewed. The causes of death were as follows: cardiomyopathy (n = 11); sudden unexpected death without morphologic findings (SUDNA, n = 6); and other cardiovascular diseases not related to OSA (n = 8). The cardiomyopathy group comprised five hearts with concentric left ventricular hypertrophy without dilatation and six with left ventricular diameter >4 cm (dilated cardiomyopathy). Four of six hearts in the SUDNA group showed right ventricular dilatation compared with seven of 11 showed cardiomyopathy and one of eight miscellaneous. The degree of obesity was greatest in the dilated cardiomyopathy group (10 of 11 obese) followed by the SUDNA group (four of six obese). The cardiac findings in patients dying suddenly and unexpectedly with OSA include nonspecific cardiomyopathy, other cardiac conditions, and hearts without a morphologic cause of death, which show frequent right ventricular dilatation as the only finding.     

The Institution of a Standardized Investigation Protocol for Sudden Infant Death in the Eastern Metropole,Cape Town,South Africa,,

The rate for the sudden infant death syndrome (SIDS) in Cape Town, South Africa, is estimated to be among the highest in the world (3.41/1000 live births). In several of these areas, including those of extreme poverty, only sporadic, nonstandardized infant autopsy, and death scene investigation (DSI) occurred. In this report, we detail a feasibility project comprising 18 autopsied infants with sudden and unexpected death whose causes of death were adjudicated according to the 1991 NICHD definitions (SIDS, n = 7; known cause of death, n = 7; and unclassified, n = 4). We instituted a standardized autopsy and infant DSI through a collaborative effort of local forensic pathology officers and clinical providers. The high standard of forensic investigation met international standards, identified preventable disease, and allowed for incorporation of research. We conclude that an effective infant autopsy and DSI protocol can be established in areas with both high sudden unexpected infant death, and elsewhere. (SUID)/SIDS risk and infrastructure challenges.     

Sudden death resulting from lesions of the cardiac conduction system

Sudden unexpected deaths in young persons with noncontributory histories, autopsy results, and drug screen results are a common problem in forensic pathology. As part of the evaluation of such cases, the cardiac conduction system (CCS) should be studied. To determine the type and incidence of lethal CCS lesions, the authors reviewed their files of sudden unexpected cardiac deaths with particular attention to cases with causes of death in the conduction system. Cases of sudden cardiac death in patients aged < or=40 years during a 10-year period (Michigan) and a 4 year-period (Spain) were selected from the files. From this group, cases were identified in which the cause of death was a lethal change in the CCS. The portions of the heart containing the CCS were excised, and at least one hematoxylin and eosin slide and at least one trichrome or elastic trichrome slide per block were studied. In the two centers, 381 cases of sudden cardiac death were identified. The most common causes of sudden cardiac death were arteriosclerotic narrowing of the coronary arteries, cardiomyopathy, and myocarditis. In 82 cases, there was no identifiable cause of death even after complete gross and microscopic autopsy was performed, a medical history was obtained, and a drug screen was performed. In 11 cases, the CCS contained lesions that were considered lethal: narrowing of the atrioventricular node artery by fibromuscular hyperplasia (7 cases) and atrioventricular node tumors (4 cases). The 11 cases accounted for 2.9% of the 381 cases of sudden cardiac death and 11.8% of the indeterminable cases. It was concluded that examination of the CCS in deaths in which the gross and microscopic autopsy, history, and drug screen fail to provide a cause of death can yield a cause of death in a significant percentage of cases. If heart block was not documented during life and no explanatory lesions were found during routine cardiac examination, examination of the CCS can yield valuable information.     

6例甲状腺功能亢进性心脏病猝死法医学分析

目的分析甲状腺功能亢进性心脏病(以下简称甲亢性心脏病)猝死案例,探讨其死亡的一般情况及法医病理学特点,为此类案件的法医病理学鉴定提供参考。方法收集中国医科大学法医学院2001—2016年6例甲亢性心脏病猝死案例,回顾性分析基本信息(性别与年龄)、临床表现、病史、解剖所见和组织病理学所见、生物化学检测指标、死亡原因。结果 6例案例多具有明确的甲状腺功能亢进病史,并表现出不同程度的心血管病症状;均具有明显的死亡诱因;甲状腺病理学检验符合弥漫性毒性甲状腺肿的表现;心脏质量均增加,心腔扩张,心肌肥大,灶状坏死;死后心包液的生物化学检测可作为甲亢性心脏病猝死的辅助手段。结论对甲亢性心脏病猝死案例进行诊断时应参考临床病史、尸体检验、组织病理学检验、死后毒(药)物检验等结果综合判定,必要时进行死后甲状腺和心功能的生物化学检测。     

Accuracy of cause of death determination without forensic autopsy examination

Medical examiners and coroners commonly determine cause and manner of death without an autopsy examination. Some death certificates generated in this way may not state the correct cause and manner of death. From the case files of the Department of Forensic Medicine in Sydney, Australia, the authors retrospectively reviewed investigative information of all cases in a 6-month period that were initially considered natural deaths (429). The authors, blinded to autopsy results, accepted 261 cases as appropriate for certification without autopsy and assigned a cause of death to each. Per standard local practice, all cases had been autopsied. The actual causes of death as determined by autopsy were then revealed and compared with the presumed causes of death. Most presumed and actual causes of death were cardiovascular (94% and 80%, respectively). The majority of presumed causes of death were listed as ASCVD as the cases lacked features of a more specific cardiovascular process. A large majority of cases had a presumed cause of death of ischemic heart disease based on individual case details. The actual causes of death demonstrated a large breadth of cardiovascular and noncardiovascular disease processes, even though ischemic heart disease accounted for 62% of deaths. The presumed cause of death was completely wrong in 28% of cases. A nonnatural manner of death was present in 3% of cases. This study demonstrates that experienced forensic pathologists may generate erroneous death certificates for cases that are not autopsied.     

Sudden Cardiac Deaths in Adults with Congenital Heart Disease with Structural Abnormalities: A Retrospective Review of Cases in the Cook County Medical Examiner's Office

Sudden cardiac death is a significant cause of mortality in adults with congenital heart disease (CHD). The Cook County Medical Examiner's Office database was queried for cases of CHD as a cause of death in the period between July 2008 and April 2019. Twenty-two cases were identified, including 11 decedents with simple defects and 10 decedents with complex defects. All of the subjects were in apparent good health at the time of death. In the absence of other obvious causes of death, simple defects were considered cases of sudden cardiac death. Significant cardiac morphological changes were common in complex defects. While 16 cases had known, diagnosed/treated CHD, 5 cases had no diagnosis prior to autopsy. In these cases, the ability to recognize CHD (sometimes subtle) helped in determining the causes of death. Therefore, forensic pathologists must be able to properly recognize various forms of CHD and request consultations, when needed.     

Cardiac pathology in 470 consecutive forensic autopsies

Cardiovascular disease continues to be the single most common generic cause of sudden and unexpected deaths. Atherosclerotic coronary heart disease and acute myocardial infarction are the most prevalent forms of fatal cardiac disease observed at autopsy. Other cardiac lesions are frequently listed as causes of death, but the prevalence of such lesions as incidental findings in the general population is unknown. In this study, 470 consecutive forensic autopsies were evaluated for minor and major anomalies. The most frequently observed major congenital finding was floppy mitral valve (5%). Tunneled coronary arteries, considered minor congenital findings, were seen in 29%. Atherosclerotic coronary heart disease was the most common major acquired finding, observed in 16% of cases. Of the 470 hearts, only 8% were considered normal.     

Arrhythmogenic right ventricular dysplasia cases in forensic autopsies

Arrhythmogenic right ventricular dysplasia or cardiomyopathy (ARVD or ARVC) is an increasingly recognized entity with clinical and forensic implications. This is the first series documenting ARVD in 5 separate cases in forensic autopsies from Turkey declared as natural sudden cardiac death following complete autopsy and toxicologic analysis. There was a male preponderance (M/F=4), with a mean age of 50.     

Pulmonary siderophages and unexpected infant death

It has been proposed that the presence of siderophages in the lungs of infants who die unexpectedly should be considered a marker of a previous hypoxic event, which may preclude a diagnosis of sudden infant death syndrome. The authors retrospectively reviewed all infant deaths (<1 year old) going to autopsy at the Denver Office of the Medical Examiner from January 1999 to January 2001. Lung sections were stained with Prussian blue, and siderophages were counted in 20 high-power fields per lobe sampled. Cell counts were performed by two independent pathologists who were blinded to history and cause of death, with good reproducibility. Iron stain results were then categorized by average number of siderophages per 20 high-power field (category 1 = <5, category 2 = 5-100, category 3A = 100-500, category 3B = >100 in a single lobe, category 4 = >500). The results were subsequently correlated to case history, autopsy findings, and cause/manner of death. Forty-three cases were reviewed. The causes of death included sudden infant death syndrome (16), asphyxia (5), undetermined (6), and other (16). Those deaths were categorized by the above criteria as follows: category 1. (32), category 2. (6), category 3. (4), and category 4. (1). All sudden infant death syndrome deaths were in category 1. Categories 1 and 2 also included deaths in which hypoxia might have been present before death because of such factors as pneumonia and congenital heart disease. Categories 3 and 4 included a known homicidal asphyxia in which repeated episodes of intentional smothering were documented, 2 probable asphyxias, 1 nonaccidental trauma, and 1 undetermined. All 5 cases had questionable circumstances surrounding the death of the infant. Pulmonary siderophages were described in only 1 of the 43 autopsy reports. It was concluded that pulmonary siderophages can be markedly increased in cases of repeated asphyxia. Siderophages may also be increased in cases where hypoxia may have been present for another reason, but not to the same degree. Siderophages are not increased in sudden infant death syndrome. Because iron-laden macrophages often are not recognized on routine examination with hematoxylin and eosin staining, iron stains may be helpful in the evaluation of infant deaths. If siderophages are present in increased amounts without an obvious explanation, further investigation is warranted.     

Intrapulmonary aquaporin-5 expression as a possible biomarker for discriminating smothering and choking from sudden cardiac death: a pilot study

The diagnosis of mechanical asphyxia as a cause of death, especially smothering and choking lacking evident injury, is one of the most difficult tasks in forensic pathology. The present study investigated the intrapulmonary expressions of aquaporins (AQPs; AQP-1 and AQP-5), as markers of water homeostasis, in forensic autopsy cases (total n=64, within 48 h postmortem) of mechanical asphyxiation due to neck compression (strangulation, n=24), including manual/ligature strangulation (n=12) and atypical hanging (n=12), smothering (n=7) and choking (n=8), compared with sudden cardiac death (n=14) and acute brain injury (n=11). Quantification of mRNA using a Taqman real-time PCR assay system demonstrated suppressed expression of AQP-5, but not AQP-1, in smothering and choking, compared with that in strangulation as well as sudden cardiac death and acute brain injury death. Immunostaining of AQP-5 was weakly detected in a linear pattern in the type I alveolar epithelial cells in smothering and choking cases, while cardiac and brain injury death showed marked positivity, and most strangulation cases had AQP-5-positive granular aggregates and fragments in intra-alveolar spaces. These observations indicate a partial difference in pulmonary molecular pathology among these causes of death, suggesting a procedure for possible discrimination of smothering and choking from sudden cardiac death.     

Postmortem Serum Tryptase Levels with Special Regard to Acute Cardiac Deaths

An elevated serum tryptase concentration is considered a specific marker for systemic mast cell activation, a central feature of anaphylaxis. However, in some cases of acute cardiovascular death, high concentrations of serum tryptase are also observed. We compared the postmortem serum tryptase concentrations in 74 cases assigned to the following four groups: anaphylactic deaths (Group A, n = 20), acute cardiac deaths (Group ACD, n = 30), acute dissecting aneurysm ruptures (Group ADA, n = 10), and controls (Group C, n = 14). Additionally, the cutoff between Group A and the other groups was calculated using receiver‐operating characteristic (ROC) curve analysis. Tryptase concentrations were markedly elevated in Group A (p < 0.001), Group ACD (p = 0.015), and Group ADA (p = 0.005). The optimal cutoff was 43 ng/mL, the sensitivity was 90%, and the specificity was 98%. While elevated concentrations of tryptase were noted in practical autopsy cases, due attention should be paid to the differential diagnosis between anaphylactic and acute cardiovascular deaths.     

Sudden death due to undiagnosed Wilms' tumor in an adult

Sudden unexpected deaths due to natural causes constitute a large number of cases encountered by the forensic pathologist. In a majority of such cases, heart disease is responsible for sudden death. Rare disease entities resulting in sudden death are occasionally encountered and may not fit the classic epidemiological profile. We present a case of sudden death due to a previously undiagnosed Wilms' tumor (WT) in an adult. The pathology of WT is discussed, as is the topic of sudden death due to previously unrecognized malignancy.     

A study of various morphologic variables and troponin I in pericardial fluid as possible discriminators of sudden cardiac death

Pathologists frequently examine victims of sudden cardiac death. In some cases, a firm diagnosis of cardiac-related death can be made based on conclusive gross and histologic findings. In many other cases, we find evidence supportive of, but not diagnostic of, cardiac death (e.g., atherosclerotic coronary artery disease, cardiomegaly, myocardial scarring). A final cohort consists of cases of sudden death with minimal to mild cardiac disease, no other significant pathology, and negative toxicologic studies. This prospective study compared 38 cardiac-related deaths with 52 control cases with respect to concentrations of pericardial cardiac troponin I (cTnI), heart weight, evidence of old and/or recent myocardial injury, and presence of significant coronary artery disease. The influence of documented chest trauma and/or perimortem cardiopulmonary resuscitation (CPR) on levels of cTnI was also analyzed. Even though median cTnI levels were significantly higher in cardiac deaths than in controls (p = .003), cTnI was not found to be a significant predictor of cardiac deaths, as determined by discriminant analysis (p = .52). Heart weight >500 g, evidence of old and recent myocardial injury, and significant coronary artery disease were seen statistically more often in cardiac deaths than in controls (p < or = .005 in each case), and median age was significantly higher in cardiac deaths than in controls (p = .001). Based on a stepwise logistic regression model, significant coronary artery disease, old and recent myocardial injury, and heart weight >500 g were found to contribute significantly to the prediction of cardiac death. Finally, neither chest injury nor CPR significantly affected concentrations of cTnI in pericardial fluid. These data confirm that the presence of acute and remote myocardial injury, significant coronary artery disease, and cardiomegaly (heart weight >500 g) strongly supports the diagnosis of a cardiac-related death. In contrast to a recently published report, we do not find that elevated concentrations of cTnI in pericardial fluid are strong indicators of cardiac-related deaths using our methodology.     

Undetermined Manner of Death: An Autopsy Series

A manner of death may be ruled undetermined by the forensic pathologist when there is insufficient information about the circumstances surrounding the death to make a ruling. The aim of our study was to retrospectively analyze a series of autopsy cases that were classified as undetermined manner of death after complete investigations. In all, 48 cases were examined. In 23 cases (48%), the cause of death was determined. The most frequent cause of death was toxic death (n = 11). More than one manner of death was deemed conceivable for most cases (n = 39). The most frequent and the most probable manner of death was accident (n = 37). Homicide was not excluded in about 23% of the cases. Our study showed that the manner of death may remain undetermined despite an established cause of death, and even when two or more conceivable causes of death are considered. Our study pointed out that undetermined manner of death covers a wide range of situations and that homicide may be underestimated.     

Ischemic heart disease and epilepsy: two major causes of out-hospital natural death in male alcoholics

The objectives of this research were to study the distribution of in- and out-hospital deaths and causes of death in male alcoholics and in particular to analyze obscure cases. In a population-based sample of 1123 men treated in one detoxification unit during 1986–1989, 97 patients with alcohol dependence (DSM-III-R) died ≤ 1 year after in-hospital detoxification. In each case, the cause and the manner of death were assessed by scrutiny of information in hospital and autopsy records, toxicological examinations, and police reports. The results were that 71 of the 97 men died outside hospital. The overall autopsy rate was 89%. Ischemic heart disease accounted for 18 out of 41 evaluable natural out-hospital deaths. Epileptic seizures were judged to be the cause of death in five cases and could also have contributed to seven out of eight obscure out-hospital deaths. Ethanol in blood or urine was detected in 19 of the 23 deaths attributed to trauma or intoxication, whereas only four out of the 18 out-hospital deaths from ischemic heart disease were ethanol-positive. It was concluded that early detection and adequate treatment of ischemic heart disease and epilepsy might improve prognosis in patients with alcohol dependence. The use of clinical information could be of crucial importance in evaluating possible causes of death, especially in obscure cases.     

The utility of histology in assessing the cause of death in medico-legal autopsies in selected trauma deaths: Suspension-, immersion-, fire-, and traffic-related

The goal of a medico-legal autopsy is primarily to determine the cause and manner of death. To this end, the pathologist often uses auxiliary analyses, including histology. However, the utility of routine histology in all medico-legal autopsies is unknown. Earlier studies on the utility of routine histology have shown inconsistent effects, with some studies recommending it and others rejecting it. To study the degree to which histology informs on the underlying cause of death, we sent autopsy reports from suspension-, immersion-, fire-, and traffic-related deaths to senior board-certified forensic pathologists and had them assess the cause of death, first without knowledge of the histological findings and then with knowledge thereof. Fifty cases were identified in each of four subgroups: fire-, immersion-, suspension-, and traffic-related deaths. The autopsy reports were anonymized, and the histological findings and conclusions were removed. Two board-certified forensic pathologists independently reviewed the reports in each subgroup and assessed the manner and underlying cause of death (including their certainty of this assessment on a five-level scale) with and without access to histological findings. The probability of changing the underlying cause of death posthistology was low in all study groups. There was a slight increase in the degree of certainty posthistology in cases where the underlying cause of death was not changed, but only when the antehistology certainty was low. Our results suggest that histology does not meaningfully inform on the underlying cause of death in suspension-, immersion-, fire-, and traffic-related deaths except when antehistology certainty is low.     

Molecular genetics of sudden cardiac death

Sudden cardiac death (SCD) is one of the most common causes of death. An important number of sudden deaths, especially in the young, are due to genetic heart disorders, both with structural and arrhythmogenic abnormalities. In recent years, significant advances have been made in understanding the genetic basis of SCD. Identification of the genetic causes of sudden death is important because close relatives are also at potential risk of having a fatal cardiac condition. A comprehensive post-mortem investigation is vital to determine the cause and manner of death and provides the opportunity to assess the potential risk to the family after appropriate genetic counselling. In this paper, we present an update of the different genetic causes of sudden death, emphasizing their importance for the forensic pathologist due to his relevant role in the diagnosis and prevention of SCD.     

A rapid postmortem cardiac troponin T assay: laboratory evidence of sudden cardiac death

Postmortem examination may be useful in establishing the cause of sudden unexpected death. In many instances, however, limitations of staffing, budget, and time may force the pathologist to triage cases to external examination rather than autopsy. A rapid assay for cardiac troponin T (cTnT) to document suspected cardiac-related deaths may optimize the use of the time and resources of the autopsy pathologist. Peripheral blood was sampled percutaneously before each of 40 autopsies and placed in the well of the Cardiac T Rapid Assay unit in accordance with the included instructions, and the results were read after 15 minutes. The assay result, decedent age, postmortem interval, and evidence of cardiopulmonary resuscitation were tabulated and subsequently correlated with the cause of death. On final sign-out of each of the autopsies, the cause of death was determined to be cardiac-related (n = 20) versus the cause in non-cardiac control subjects (n = 20). This determination was made while the investigators were blinded to the cTnT assay result. Of the 20 cardiac deaths, 17 (85%) showed positive results for cTnT compared with 6 (30%) false-positive results among the 20 control cases; this result was statistically significant according to the chi-square test. In the over-50 age group, the sensitivity of this assay in detecting cardiac-related death was 91%, with a specificity of 86%. Perimortem cardiopulmonary resuscitation did not appear to result in false-positive results. In the appropriate setting, this rapid assay for cTnT can provide valuable data supportive of a cardiac-related death. This inexpensive test may best be used in triaging sudden deaths in persons over 50 to external examination versus complete autopsy.