Analysis of sudden unexpected death in southern Ontario,with emphasis on myocarditis.

The records of all 2427 autopsies performed at the Brantford (Ont.) General and Paris (Ont.) Willett hospitals from Jan. 1, 1969 to Aug. 15, 1978 were reviewed. Of the 1299 cases of sudden unexpected death investigated by a coroner almost 28% were due to unnatural causes--violence or poisoning. The main cause of natural sudden death was coronary artery disease, which accounted for 43.3% of all the sudden unexpected deaths. In 20 cases the cause of death was thought to be viral myocarditis, and in 9 of the 20 there was serologic evidence of at least previous coxsackievirus disease. Two of the nine cases were of special interest because of the finding of giant-cell myocarditis in one and aortic valve disease in the other. Eleven of the 20 persons were aged 13 to 46 years. These findings support the view that the most serious manifestation of enterovirus infection today is cardiac damage by coxsackieviruses.     

Changes in surface-charge density of blood cells after sudden unexpected death

The objective of the investigation was evaluation of postmortem changes of electric charge of human erythrocyte and thrombocyte membranes after sudden unexpected death. The surface charge density values were determined on the basis of the electrophoretic mobility measurements of the cells carried out at various pHs of electrolyte solution. The interactions between both erythrocyte and thrombocyte membranes and electrolyte ions were studied. Values of parameters characterizing the membrane--that is, the total surface concentrations of both acidic and basic groups and their association constants with solution ions--were calculated on the basis of a four-equilibria mathematical model. The model was validated by comparison of these values to experimental data. We established that examined electric properties of the cell membranes are affected by sudden unexpected death. Postmortem processes occurring in the cell membranes can lead to disorders of existing equilibria, which in turn result in changes in values of all the above-mentioned parameters.     

LHRH in the human hypothalamus. Immunohistochemical mapping in normal newborn infants or in sudden death infants

The topographical distribution of neurons containing LHRH has been investigated in newborn hypothalamus using the peroxidase anti-peroxidase technique. In control subjects, LHRH immunoreactive (LHRH-IR) perikarya have been mainly observed essentially in the infundibular nucleus. The preoptic region displayed a moderate density of LHRH-IR cell bodies. High LHRH innervation was observed in the anterior hypothalamus in the lamina terminalis and in the mediobasal hypothalamus in the median eminence, and in the peri- and paraventricular regions. In sudden death infant syndrome, a comparable mapping was observed, except a low density in the mediobasal peri- and paraventricular areas.     

Circadian variation of the frequency of sudden infant death syndrome and of sudden death from life-threatening conditions in infants

136 infants died of sudden infant death syndrome (SIDS) and 140 infants died suddenly and unexpectedly from life-threatening conditions (LTC) from 1983 to 1989 in Leningrad entered the study. 24-hour distribution of death cases was evaluated in both studied groups. The increased incidence of SIDS was revealed from 04(00) to 06(00). There was not significant difference between circadian variation of SIDS and that of death from LTC. The early morning seems to be the time when the risk factors that lead to sudden death are likely to be prominent.     

Evidence for infection, inflammation and shock in sudden infant death: parallels between a neonatal rat model of sudden death and infants who died of sudden infant death syndrome

This study compared pathological findings from a neonatal rat model of sudden death with those from 40 sudden infant death syndrome (SIDS) infants collected at autopsy. In the rat model, influenza A virus was administered intranasally on postnatal day 10, and on day 12 a sublethal, intraperitoneal dose of Escherichia coli endotoxin; mortality was 80%. Tissue samples from the animals and infants were fixed in formaldehyde, embedded in paraffin, and sections stained with hematoxylin and eosin. Tissues from the SIDS specimens were additionally cultured for bacteria and viruses; post-mortem blood samples were evaluated for signs of inflammation. All sections were examined by a pediatric forensic pathologist familiar with SIDS pathology. Comparisons between the rat model and the human SIDS cases revealed that both exhibited gross and microscopic pathology related to organ shock, possibly associated with the presence of endotoxin. Uncompensated shock appeared to be a likely factor that caused death in both infants and rat pups. Response to a shock-inducing event might have played an important role in the events leading to death. The similarities between the neonatal rats and the human cases indicate that further research with the model might elucidate additional aspects of SIDS pathology.     

Alcohol intemperance and sudden death.

Ten years after a health screening examination was offered to 50 year old men 32 of the 2322 participants and 12 of the 454 nonparticipants had died of ischaemic heart disease. Of these, 26 and 11 respectively had suffered sudden death, for which necropsy was performed. Half of the men who had died suddenly had been registered for alcohol intemperance up to 1973, which was four times the prevalence of such registrations in the general population. Registration at both the Swedish Temperance Board and the Bureau of Social Services was associated with an odds ratio of 3.74 for sudden death as compared with not being registered at either. Logistic analysis including the classical risk factors for ischaemic heart disease together with registration for alcohol intemperance and at the Bureau of Social Services showed only the two types of registration and systolic blood pressure to be independent risk factors. On the other hand, there was no overrepresentation of subjects entered in the registers among those surviving a myocardial infarction. For non-fatal myocardial infarction blood pressure and serum triglyceride concentration were significant risk factors and serum cholesterol concentration, smoking, and body mass index probable risk factors; the two types of registration were not independent risk factors. Alcohol intemperance is strongly associated with an increased risk of sudden death after myocardial infarction.     

The electrophysiologic features of sudden death.

Sudden or instantaneous death is nearly always of cardiac origin. The most common mechanism is a severe electrical dysfunction, which is apparent on Holter monitoring tapes. Identifying patients at risk of sudden cardiac death is difficult, and Holter monitoring has proved to be limited in its diagnostic usefulness. However, in patients who have experienced cardiac arrest Holter monitoring has shown that the electrical abnormalities leading to death vary. These abnormalities usually take time to develop, and during this time the cerebral circulation is partially maintained. In this brief period, lasting less than 2 minutes, the individual may become aware that something is wrong and have time to react.