Abstract: In order to explore the specificity of anti-muscle actin monoclonal antibody HHF35 in the postmortem diagnosis of early myocardial infarction, the changes of HHF35 staining in the infarcted myocardia and other non-infarcted myocardia with direct or indirect myocar- dial injury were studied with immunohistochemical S-P method. The results showed that the loss of HHF35 staining of different degrees was found in the infarcted myocardia, but also in the other non-infarcted myocardia with direct or indirect myocardial injury, such as cardiac contusion, myocarditis, hemorrhagic shock, electrocution, mechanical asphyxia. So it should be cautious in diagnosing early myocardial infarction with HHF35 immunohistochemisrty.

Key words: early myocardial infarction, HHF35