Coronary CT angiography for the assessment of atherosclerotic plaque inflammation: post-mortem proof of concept with histological validation

Purpose To evaluate the pathological nature of the radiological feature of “atherosclerotic plaque enhancement,” we compared computed tomography (CT) characteristics of fatal coronary plaques obtained from autopsies of sudden coronary death on post-mortem coronary computed tomography angiography (CCTA) with histological examination. Methods A retrospective study was conducted in a tertiary forensic centre, in which cases referred for autopsy systematically undergo CT before histopathological analysis. Fifty cases with autopsy-proven fatal coronary thrombosis were selected, and the culprit lesion was determined pathologically. CT images were assessed for plaque density increase on CCTA vs. non-contrast CT by two radiologists in consensus, and cases deemed positive were included for radiology-pathology correlation analysis. Histological samples were assessed by two forensic pathologists in consensus; plaque and periadventital inflammation as well vasa vasorum were evaluated semi-quantitatively. Results Ten cases showed a clear sign of radiological plaque enhancement (four women, six men, mean age 53 ±6.6, min 43, max 67). Histologically, coronary thrombosis was described as an erosion in three cases, as a rupture in six cases and a recanalized thrombosis in one case. In nine cases, there was periadventitial inflammation, considered as severe in five cases. In eight of these nine cases, there was a severe increase of vasa vasorum. We observed moderate or severe plaque inflammation in eight cases. Conclusion Plaque enhancement detected by post mortem CCTA appears clearly to correlate with histopathological presence of perivascular plaque inflammation and increase of vasa vasorum. Our findings open the door to further validation studies and hopefully translation to clinical use