Ischemic and non-ischemic myocardial injuries at autopsy- an overview for forensic pathologists

Cardiovascular diseases are major causes of morbidity and death worldwide, and most cardiac deaths are related to ischemic injury of the myocardium (myocardial infarction). As underlined in the current clinical definition and classification of myocardial infarctions, not all myocardial injuries are due to ischemia: irreversible injury, ending in necrosis, can be induced also by various other factors, such as infections, immune disorders, physical and chemical agents, and trauma. This is supported by clinical studies showing that elevated serum levels of cardiac troponins, as a measure of myocardial damage, are also a common finding in the non-ischemic types of myocardial injury. Forensic pathologists confronted with autopsy findings suggestive of myocardial injury should therefore realize that both ischemic and non-ischemic forms of myocardial death can be observed, and not only in natural but also non-natural deaths (intoxications, asphyxia, traumatic and iatrogenic deaths, and others). Distinguishing these different types of injuries and underlying diseases or circumstances of death is critical, not only to determine the cause and mechanism of death, but also to help investigate often challenging medico-legal scenarios. This article reviews the broad spectrum of ischemic and non-ischemic myocardial injuries in natural and violent deaths. From this perspective we propose a diagnostic approach to myocardial injuries in a forensic pathology context.