Study of early ischemic myocardial damage in forensic pathology

早期缺血性心肌损伤的尸检诊断一直是法医学实践中的一个复杂问题。我们检查了长崎大学医学院法医学系共63例尸检获得的心脏组织病理学结果。死因依次为自然死亡、窒息、创伤性休克和头部损伤。在常规组织学苏木精-伊红(H&E)染色和Mallory磷钨酸苏木素(PTAH)染色的基础上，应用细胞间黏附分子、补体C9和肌钙蛋白I(心肌特异性蛋白)的抗体进行免疫组织化学染色。纤维连接蛋白和补体C9的成分被认为在心肌损伤时可能在心肌细胞中表达，而肌钙蛋白I被认为在心肌损伤时可能从心肌细胞中丢失。这些标记物的免疫组织化学染色模式因病例而异。这些结果反映了这三种标志物在心肌损伤过程中的敏感转变。此外，我们使用74例法医尸检心脏的每一块左心室块，用补体成分C9的免疫组织化学技术检测早期缺血性心肌损伤。结果得出结论，心肌细胞上的C9染色是早期缺血性心肌损伤的可靠标记物，因为它足够敏感，只需从每个患者的一个区块就能检测到。此外，虽然有11例标本在福尔马林中固定了一年以上，但C9的免疫染色没有受到影响。在回顾性法医标本中，C9的这种免疫染色是一种简单且有价值的检测早期缺血性心肌损伤的方法。在回顾性法医标本中，C9的这种免疫染色是一种简单且有价值的检测早期缺血性心肌损伤的方法。

The postmortem diagnosis of early ischemic myocardial damage has lain as intricate problem on forensic practice.We examined the histopathological findings of heart of a total of sixty-three cases obtained in the autopsies at the Department of Legal Medicine in Nagasaki University School of Medicine. Their causes of death were natural death, asphyxia, traumatic shock and head injury. We used the immunohistochemical staining by the antibodies to Fibronectin, i.e. the intercellular adhesion molecule, component of complement C9 and Troponin I, i.e. the specific protein of myocardium, in addition to conventional histological staining with hematoxylin and eosin (H&E) and Mallory's phosphotungstic acid hematoxylin (PTAH) method. Fibronectin and component of complement C9 are considered that they may be expressed in cardiomyocytes at myocardial damage and Troponin I is regarded as it may loss from cardiomyocytes at myocardial damage conversely. The immunohistochemical staining pattern of these markers were varied from case to case. These results suggested that these findings reflected the sensitive transitions of these three markers during myocardial damage.Furthermore, we used each single block of left ventricle from 74 forensic autopsy hearts to detect the early ischemic myocardial damage with immunohistochemical technique for complement component C9. The results lead the conclusion that C9 staining on cardiomyocytes is a reliable marker for early ischemic myocardial damage since it was sensitive enough to detect from just one block of each patient. Moreover, although in eleven cases the samples were fixed in formalin over one year, the immunostaining of C9 was not affected. This immunostaining for C9 is simple and valuable to detect early ischemic myocardial damage in retrospective forensic specimens. This immunostaining for C9 is simple and valuable to detect early ischemic myocardial damage in retrospective forensic specimens.