Analysis of cardiac troponins and creatine kinase MB in cerebrospinal fluid in medicolegal autopsy cases.

Previous studies suggested the usefulness of postmortem cardiac troponin (cTn) and creatine kinase MB (CKMB) levels in blood and pericardial fluid for investigating myocardial damage in the death process. The present study investigated the postmortem levels in cerebrospinal fluid (CSF), using serial medicolegal autopsy cases (n=257, within 48h postmortem). For CSF, the postmortem increase was slight for cTnT and cTnI, and was not significant for CKMB. A moderate correlation was seen between cTnT and cTnI levels (r=0.598, p<0.0001), whereas the correlations of cTnT and cTnI with CKMB were insignificant. The correlation between peripheral blood and CSF levels was significant for cTnT and cTnI, but insignificant for CKMB. Marked concomitant increases in CSF cTnT and cTnI levels were seen for protracted asphyxiation and hyperthermia (heat stroke). In addition, marked elevation of CSF cTnI was detected in some cases of acute cardiac death. Increased CKMB was apparently independent of the cause of death, and was frequently seen in acute or subacute deaths. These findings suggest that CSF levels of cTnT and cTnI are useful for investigating the progress and duration of myocardial damage in the death process. CKMB may be used as a marker of persistent hypoxic myocardial damage before death.