title: Cardiothoracic ratio in postmortem chest radiography with regard to the cause of death.
abstract: It is difficult to examine the intact in situ status of thoracic organs, including the heart and lungs, after opening the chest at autopsy. The present study investigated the pathological diagnostic significance of the cardiothoracic ratio (CTR) with regard to heart and lung weight in postmortem plain chest radiography. The pathological diagnostic significance of the CTR in postmortem plain chest radiography using serial forensic autopsy cases of adults (>19 years of age, n=367, within 72 h postmortem) was retrospectively investigated. In natural deaths, CTR was larger for heart diseases, and was smaller for pulmonary infection and gastrointestinal bleeding, showing correlations to the heart weight except in cases of hemopericardium. In traumatic deaths, CTR was larger in cases of fire fatality and acute methamphetamine intoxication, and varied in cases of blunt injury, showing correlations to the heart weight. However, CTR was smaller for sharp instrument injury and drowning, independently of the heart weight. These findings suggest that postmortem CTR (median, 55.6%, measured using a mobile X-ray apparatus) primarily depends on the heart weight, but is substantially modified during the process of death: the CTR may be enlarged by cardiac dilatation due to terminal congestive heart failure, but may be reduced by inflated lungs in drowning or hypovolemia due to fatal hemorrhage. CTR showed a mild correlation to the right diaphragm level, which was also related to the cause of death, but was independent of the left diaphragm level. Plain chest radiographic findings may also be helpful in investigating the pathophysiology of death, and are to some extent comparable with clinical findings. This also suggests the potential usefulness of postmortem CT and MRI for analysis of terminal cardiac function.
authors.affiliation: Department of Legal Medicine, Osaka City University Medical School, Asahi-machi 1-4-3, Abeno, Osaka 545-8585, Japan. michi.leg@med.osaka-cu.ac.jp
authors.forename: Tomomi
authors.initials: T
authors.lastname: Michiue
authors.forename: Takaki
authors.initials: T
authors.lastname: Ishikawa
authors.forename: Shigeki
authors.initials: S
authors.lastname: Sakoda
authors.forename: Li
authors.initials: L
authors.lastname: Quan
authors.forename: Dong-Ri
authors.initials: DR
authors.lastname: Li
authors.forename: Yasunobu
authors.initials: Y
authors.lastname: Kamikodai
authors.forename: Shuji
authors.initials: S
authors.lastname: Okazaki
authors.forename: Bao-Li
authors.initials: BL
authors.lastname: Zhu
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Maeda
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001344:Autopsy; D002423:Cause of Death; D005260:Female; D049429:Forensic Pathology; D006321:Heart / Q000502:physiology*; D006801:Humans; D008168:Lung / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009929:Organ Size / Q000502:physiology*; D013902:Radiography, Thoracic; D012189:Retrospective Studies; D014947:Wounds and Injuries / Q000401:mortality / Q000473:pathology; D055815:Young Adult