Immunohistochemical study of troponin for postmortem diagnosis of early myocardial infarction

"nBackground: The postmortem diagnosis of early myocardial infarction is a perplexing affair in forensic pathology. The routine evaluations of autopsied hearts including macroscopic examination and study of H&E stained sections are often not contributory. Some other methods like electron microscopy need sophisticated equipments which are not available in all pathology laboratories. "nMethods: In an attempt to find a more reliable and less labor- intensive method, we have studied the diagnostic value of cardiac troponin- T by an optimized immunohistochemical method on 67 autopsied hearts in Legal Medicine Organization of Iran. The cases were divided into three groups: the positive group composed of cases with the definite diagnosis of myocardial infarction (MI) as the cause of death; the non-cardiac death group; and finally the suspicious group which consisted of cases with high probability of early myocardial infarction, however without definite evidence of MI on the routine histopathologic studies. In stained sections, the degree of troponin T depletion was scored. "nResults: With our proposed cut off, this test showed positive results in 19 out of 22 cases in MI group (86.4%), none of the 17 cases of non-cardiac death (100% specificity), and 15 out of 28 cases of suspicious group (53.6%). "nConclusions: This relatively easy method may increase the sensitivity of routine histopathologic methods in postmortem detection of early myocardial infarction. Additionally, this method does not require a particular preparation and can be done very easily on the archival paraffin blocks available in pathology departments whenever further evaluation is deemed necessary by the pathologist