Diagnostic role of postmortem CK-MB in cardiac death: a systematic review and meta-analysis

Biochemical analysis of creatine kinase MB (CK-MB), which is a biomarker of myocardial damage, is used as a potential adjunct test in clinical and forensic medicine. However, there is no previous meta-analysis that summarizes the diagnostic value of postmortem biochemical analysis of CK-MB in cardiac death. The purpose of this study was to perform a systematic literature review and meta-analysis of postmortem CK-MB in cardiac death for forensic work. Six online databases, including PubMed, Embase, Cochrane Library, the China National Knowledge Infrastructure (CNKI), the China Biomedical Literature Database (CBM), and Wanfang Data, were used to search for related studies. The quality of the included literature was assessed according to the Newcastle-Ottawa Quality Assessment Scale (NOS). The meta-analysis was performed by Review Manager version 5.3 software to investigate the diagnostic role of postmortem CK-MB in cardiac death, especially in myocardial infarction. Sixteen pieces of related literature were identified, all of which were considered high quality. The results of the meta-analysis revealed that the postmortem CK-MB level in the pericardial fluid was significantly higher in the cardiac death group with a standard mean difference (SMD) = 0.63, 95% confidence interval (CI) = 0.09~1.17, p = 0.02. This was also the result in the myocardial infarction group (SMD = 0.83, 95% CI = 0.10~1.56, p = 0.03). No significant difference in CK-MB was found in serum for cardiac death (SMD = -0.31, 95% CI = -0.85~0.24, p = 0.27) or myocardial infarction (SMD = -0.10, 95% CI = -0.69~0.49, p = 0.74). The postmortem biochemical analysis of CK-MB in the pericardial fluid can be used as an auxiliary method in the postmortem diagnosis of cardiac death, along with autopsy and histological investigation.