Potential use of pericardial cTnI, Mg2+ and Ca2+ in the forensic investigation of seawater drowning in Greece: An initial assessment

The investigation of drowning constitutes one of the biggest problems in forensic practice. Elevated cardiac troponin I (cTnI) levels in biological fluids have been associated with myocardial damage, whereas increased Mg2+ and Ca2+ levels were found in cases of seawater drowning. The aim of this study was to examine the diagnostic utility of postmortem determination of cTnI, Mg2+ and Ca2+ in the pericardial fluid, in differentiating between cases of seawater drowning related to myocardial injury and those brought about by other causes. This study included 76 cases selected during a 2-year period from medicolegal autopsies. The cases were divided into three groups, according to the cause of death established based on macroscopic and microscopic evidence. The groups were: 1) seawater drowning (n = 23), 2) seawater drowning with histological evidence of myocardial infarction (n = 28), and 3) myocardial infarction unrelated to drowning (n = 25). cTnI was determined with an enzyme immunoassay; Mg2+ and Ca2+ with standard colorimetric assays. Pericardial cTnI levels were significantly lower in group 1 compared to groups 2 and 3. In contrast, pericardial Mg2+ and Ca2+ levels were both significantly higher in groups 1 and 2 compared to group 3. Our results suggest that the postmortem determination of pericardial cTnI levels may be useful in detecting previous myocardial damage as a contributory factor in death from seawater drowning and provide independent confirmation of the usefulness of pericardial Mg2+ and Ca2+ levels for differentiating between seawater drowning and fatal acute myocardial injury unrelated to the former.