Lin, Peter T.

AimsGiant cell arteritis (GCA) is a systemic vasculitis affecting medium and large arteries in patients aged over 50 years. Involvement of temporal arteries (TA) can lead to complications such as blindness and stroke. While the diagnostic gold standard is temporal artery biopsy (TAB), comorbidities and age‐related changes can make interpretation of such specimens difficult. This study aims to establish a baseline of TA changes in subjects without GCA to facilitate the interpretation of TAB.Methods and resultsBilateral TA specimens were collected from 100 consecutive eligible postmortem examinations. Subjects were divided into four age groups and specimens semiquantitatively evaluated for eccentric intimal fibroplasia, disruption and calcification of the internal elastic lamina (IEL), medial attenuation and degree of lymphocytic inflammation of the peri‐adventitia, adventitia, media and intima. The individual scores of intimal fibroplasia, IEL disruption and medial attenuation were added to yield a ‘combined score (CS)’. Seventy‐eight 78 decedents were included in the final analysis following exclusion of 22 individuals for either lack of clinical information or inability to collect TA tissue. A total of 128 temporal artery specimens (50 bilateral from individual decedents, 28 unilateral) were available for examination. Intimal proliferation, IEL loss, IEL calcification and CS increased with age in a statistically significant fashion. Comparison of the oldest age group with the others showed statistically significant differences, although this was not uniformly preserved in comparison between the three youngest groups.ConclusionSenescent arterial changes and healed GCA exhibit histological similarity and such changes increase proportionally with age. The CS demonstrates significant association with age overall and represents a potential avenue for development to ‘normalise’ TA biopsies from older individuals.

Significance Approximately 400 United States children 1 y of age and older die suddenly from unexplained causes annually. We studied whole-exome sequence data from 124 “trios” (decedent child and living parents) to identify genetic risk factors. Nonsynonymous mutations, mostly de novo (present in child but absent in both biological parents), were highly enriched in genes associated with cardiac and seizure disorders relative to controls, and contributed to 9% of deaths. We found significant overtransmission of loss-of-function or pathogenic missense variants in cardiac and seizure disorder genes. Most pathogenic variants were de novo in origin, highlighting the importance of trio studies. Many of these pathogenic de novo mutations altered a protein network regulating calcium-related excitability at submembrane junctions in cardiomyocytes and neurons.

AbstractExtracorporeal membrane oxygenation (ECMO) employs vascular cannulation and a gas exchange circuit to provide support to patients with severely compromised cardiopulmonary function. ECMO is often the last intervention taken before death and thus presents a unique challenge to medical examiners. This study describes the characteristics of decedents on ECMO at the time of death, including clinical indications, types of circuit configurations, causes and manners of death, gross findings at autopsy, and therapeutic complications. Files of a regional medical examiner office within an academic medical center were searched for the period between 2013 and 2019. Nineteen cases were identified with a median age of 36 years. The circumstances surrounding the initial presentation included: sudden death, trauma, substance abuse, homicide, therapeutic complication, work‐related injury, drowning, and hypothermia. The underlying causes of death included injury‐related, as well as respiratory and cardiac‐related natural diseases. The time spent on ECMO varied from less than 1 h to 10 months. Complications encountered due to ECMO included cannulation site bleeding, pneumohemopericardium, retroperitoneal hematoma, limb ischemia, clotting, and cannula dislodgement. The patient population likely to receive ECMO has significant overlap with death circumstances likely to be reported to the medical examiner. As ECMO therapy has become increasingly available, it is of importance for medical examiners and death investigators to be familiar with the procedure as well as its limitations. Familiarity with ECMO and its sequelae allows for the proper documentation of postmortem findings and fosters an informed determination of the cause and manner of death.

AbstractThe current standard technique for cardiopulmonary resuscitation (CPR), initially described in the early 1960s, has quickly become the expected response for all persons found without a pulse or respiration. Despite the potentially lifesaving properties of external cardiac massage, the mainstay of resuscitation, it consists of repeated blunt force trauma to the chest, which can lead to extensive traumatic skeletal and nonskeletal injuries. Numerous autopsy‐based studies have documented the incidence and patterns of rib and sternal fractures associated with attempted CPR, but there is relatively little data on the incidence and severity of nonskeletal CPR‐related injuries. We reviewed reports from 1878 autopsies performed between September 2017 and December 2019 (inclusive), for documentation of CPR‐related injuries. Among these cases, there were 93 cases with resuscitation‐related nonskeletal injuries. The most common type of injury identified were visceral contusions, documented in 57.0% of cases. These contusions predominantly involved the heart, lungs, neck soft tissue, and surrounding structures. Resuscitation‐related lacerations were seen in 17.2% of the cases, most predominantly involving the pericardium, heart, and liver. Statistical analysis of the data demonstrated that lacerations were more likely to be seen in females and with associated sternal fractures. Additionally, hemothoraces were present in 34.4% of cases and hemopericardium was seen in 8.6% of cases. This study provides additional documentation of the range, severity, and incidence of various types of resuscitation‐related visceral injuries to better assist autopsy pathologists in distinguishing these injuries from other antecedent traumatic injuries.

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its resultant clinical presentation, coronavirus disease 2019 (COVID-19), is an emergent cause of mortality worldwide. Cardiac complications secondary to this infection are common; however, the underlying mechanisms of such remain unclear. A detailed cardiac evaluation of a series of individuals with COVID-19 undergoing postmortem evaluation is provided, with 4 aims: (1) describe the pathological spectrum of the myocardium; (2) compare with an alternate viral illness; (3) investigate angiotensin-converting enzyme 2 expression; and (4) provide the first description of the cardiac findings in patients with cleared infection. Methods: Study cases were identified from institutional files and included COVID-19 (n=15: 12 active, 3 cleared), influenza A/B (n=6), and nonvirally mediated deaths (n=6). Salient information was abstracted from the medical record. Light microscopic findings were recorded. An angiotensin-converting enzyme 2 immunohistochemical H-score was compared across cases. Viral detection encompassed SARS-CoV-2 immunohistochemistry, ultrastructural examination, and droplet digital polymerase chain reaction. Results: Male sex was more common in the COVID-19 group ( P =0.05). Nonocclusive fibrin microthrombi (without ischemic injury) were identified in 16 cases (12 COVID-19, 2 influenza, and 2 controls) and were more common in the active COVID-19 cohort ( P =0.006). Four active COVID-19 cases showed focal myocarditis, whereas 1 case of cleared COVID-19 showed extensive disease. Arteriolar angiotensin-converting enzyme 2 endothelial expression was lower in COVID-19 cases than in controls ( P =0.004). Angiotensin-converting enzyme 2 myocardial expression did not differ by disease category, sex, age, or number of patient comorbidities ( P =0.69, P =1.00, P =0.46, P =0.65, respectively). SARS-CoV-2 immunohistochemistry showed nonspecific staining, whereas ultrastructural examination and droplet digital polymerase chain reaction were negative for viral presence. Four patients (26.7%) with COVID-19 had underlying cardiac amyloidosis. Cases with cleared infection had variable presentations. Conclusions: This detailed histopathologic, immunohistochemical, ultrastructural, and molecular cardiac series showed no definitive evidence of direct myocardial infection. COVID-19 cases frequently have cardiac fibrin microthrombi, without universal acute ischemic injury. Moreover, myocarditis is present in 33.3% of patients with active and cleared COVID-19 but is usually limited in extent. Histological features of resolved infection are variable. Cardiac amyloidosis may be an additional risk factor for severe disease.

Context.— Respiratory failure appears to be the ultimate mechanism of death in most patients with severe coronavirus disease 2019 (COVID-19) infection. Studies of postmortem COVID-19 lungs largely report diffuse alveolar damage and capillary fibrin thrombi, but we have also observed other patterns. Objective.— To report demographic and radiographic features along with macroscopic, microscopic, and microbiologic postmortem lung findings in patients with COVID-19 infections. Design.— Patients with confirmed COVID-19 infection and postmortem examination (March 2020–May 2020) were included. Clinical findings were abstracted from medical records. Lungs were microscopically reviewed independently by 4 thoracic pathologists. Imaging studies were reviewed by a thoracic radiologist. Results.— Eight patients (7 men, 87.5%; median age, 79 years; range, 69–96 years) died within a median of 17 days (range, 6–100 days) from onset of symptoms. The median lung weight was 1220 g (range, 960–1760 g); consolidations were found in 5 patients (62.5%) and gross thromboemboli were noted in 1 patient (12.5%). Histologically, all patients had acute bronchopneumonia; 6 patients (75%) also had diffuse alveolar damage. Two patients (25%) had aspiration pneumonia in addition. Thromboemboli, usually scattered and rare, were identified in 5 patients (62.5%) in small vessels and in 2 of these patients also in pulmonary arteries. Four patients (50%) had perivascular chronic inflammation. Postmortem bacterial lung cultures were positive in 4 patients (50%). Imaging studies (available in 4 patients) were typical (n = 2, 50%), indeterminate (n = 1, 25%), or negative (n = 1, 25%) for COVID-19 infection. Conclusions.— Our study shows that patients infected with COVID-19 not only have diffuse alveolar damage but also commonly have acute bronchopneumonia and aspiration pneumonia. These findings are important for management of these patients.

Abstract Aims Coronavirus disease 2019 (COVID-19) due to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been associated with cardiovascular features of myocardial involvement including elevated serum troponin levels and acute heart failure with reduced ejection fraction. The cardiac pathological changes in these patients with COVID-19 have yet to be well described. Methods and results In an international multicentre study, cardiac tissue from the autopsies of 21 consecutive COVID-19 patients was assessed by cardiovascular pathologists. The presence of myocarditis, as defined by the presence of multiple foci of inflammation with associated myocyte injury, was determined, and the inflammatory cell composition analysed by immunohistochemistry. Other forms of acute myocyte injury and inflammation were also described, as well as coronary artery, endocardium, and pericardium involvement. Lymphocytic myocarditis was present in 3 (14%) of the cases. In two of these cases, the T lymphocytes were CD4 predominant and in one case the T lymphocytes were CD8 predominant. Increased interstitial macrophage infiltration was present in 18 (86%) of the cases. A mild pericarditis was present in four cases. Acute myocyte injury in the right ventricle, most probably due to strain/overload, was present in four cases. There was a non-significant trend toward higher serum troponin levels in the patients with myocarditis compared with those without myocarditis. Disrupted coronary artery plaques, coronary artery aneurysms, and large pulmonary emboli were not identified. Conclusions In SARS-CoV-2 there are increased interstitial macrophages in a majority of the cases and multifocal lymphocytic myocarditis in a small fraction of the cases. Other forms of myocardial injury are also present in these patients. The macrophage infiltration may reflect underlying diseases rather than COVID-19.

Abstract We present a case report of a 25 year-old man with MELAS (Mitochondrial Encephalopathy, Lactic Acidosis, and Stroke-like episodes) syndrome, who died suddenly and unexpectedly from diabetic ketoacidosis. This case report illustrates why it is important for medical examiners to be familiar with the clinical and autopsy features of MELAS syndrome and to be aware of the common complications, which may lead to sudden unexpected death.

Evidence of prior autoerotic asphyxia is often difficult to establish due to the decedent's efforts to hide the activity from others. In this case report, we suggest that a healed fracture of the thyroid cartilage is indicative of prior autoerotic asphyxia activity. The decedent was a 45-year-old man who was found unclothed on the floor of his bedroom with a belt ligature around the neck. A second rope ligature was loosely wrapped around the decedent's wrists, scrotum, and penis. A definitive escape mechanism was not identified, but a nearby towel and barbell weight may have comprised a possible escape mechanism. There was no known history of depression or prior autoerotic activity. Autopsy was notable for the presence of a healed fracture of the right superior horn of the thyroid cartilage. Three-dimensional (3D) surface scanning and 3D printing was utilized to preserve the anatomical findings prior to histologic sampling. To our knowledge, this is the first reported use of 3D surface scanning and 3D printing for the purpose of documenting a forensic finding prior to alteration of the anatomical specimen for histologic sampling. Acute fractures of the superior horns of the thyroid cartilage are not infrequently seen in ligature hanging. Therefore, the presence of a healed fracture in the setting of autoerotic asphyxia likely indicates prior activity. Histologic sampling of the laryngeal cartilages to detect occult healed fractures in autoerotic asphyxia may be useful. Three-dimensional scanning and printing may alleviate concerns for specimen alteration due to histology sampling.