A study of the myocardial depressant factor and its relative influence in drug/alcohol mortality.

A shock factor, a low molecular weight peptide, has been isolated from postmortem blood. High levels of this peptide, which depresses the myocardium, were seen in cases where drug overdose or alcoholism, or both, were the cause of death. An elevated myocardial depressant factor (MDF) level also demonstrated in a fire victim and a patient in cardiogenic shock. The peptide analysis was accomplished by using an isolated cat papillary muscle followed by paper chromatographic confirmation. Postmortem electrolytes, alcohol, and various toxic agents were eliminated as causes of myocardial depression in the isolated cat papillary muscle assay. The presence of elevated MDF levels may be significant in the overall death process.