Cadaver clots: a systematic review of the literature

Cadaveric blood is ubiquitous, and observed in various forms-liquid, coagulated, and clot-like-during autopsies. Understanding its state in postmortem vessels is essential for both scientific research and forensic investigations. Pulmonary thromboembolism (PT) is a leading cause of sudden death, often requiring medicolegal evaluation. While thrombus formation is primarily explained by Virchow's triad, the distinction between antemortem, agonal, and postmortem clot (PMC) pathogenesis remains debated. This study aims to systematically review the literature to clarify the morphological and pathological differences among these entities in forensic practice. A systematic review of PubMed, Science Direct, Scopus, and Web of Science was conducted using predefined key terms: "clot," "thrombus," "chicken-fat," "agonal," "postmortem," and "autopsy." Articles were screened for relevance, and 11 studies meeting the inclusion criteria were analyzed. The review highlights a significant gap in comparative studies addressing antemortem versus postmortem clots. The literature lacks a consensus regarding their definitions, macroscopic and microscopic characteristics, pathogenesis, and relevance to determining the cause and timing of death. Existing studies present conflicting interpretations, limiting the reliability of forensic differentiation. The current understanding of antemortem, agonal, and postmortem clots remains incomplete. Our findings underscore the need for further research to establish standardized criteria for distinguishing clot types, which is crucial for forensic pathology and medicolegal evaluations.