Demonstration of early myocardial ischaemic damage

The scope of the study was to evaluate critically histological methods which would enable myocardial ischaemic damage in the pre-infarction stage to be demonstrated unequivocally in human tissue. Blocks taken routinely at autopsy are fixed in formalin and embedded in paraffin; staining procedures adopted were carried out on such material.(1) Immunohistochemical staining with polyclonal and monoclonal, commercially available antibodies for cardiac myocyte constituent organelles and structural proteins.(2) Demonstration of lectin binding on the surface and cytoplasm of human myocardium. The cases investigated were collected in the process of routine forensic autopsies; as controls, blocks from hearts from patients dying from recent acute myocardial infarction visible macroscopically were chosen. As negative controls, cardiac blocks from persons dying of non -cardiac conditions were chosen.The antibodies and the lectins were carefully titrated to obtain optimal results.Two main methods of identifying tissue damage were investigated:There were reproducible changes in the ischaemic zones, but single antibodies or lectins did not produce singly pathognomonic and reproducible results. A battery of stains and lectins would have to be used in serial sections of the same block to prove that an area of suspected ischaemia is indeed showing structural abnormalities