Histopathological findings in dissection and rupture of the thoracic aorta. Study of 54 autopsy cases

Introduction

Thoracic aortic dissection/rupture has a high mortality, constituting 3.9%–5.4% of sudden deaths (SD) in forensic series. Medial histopathological findings associated with these entities have received multiple terms and definitions. In 2016, the European Association for Cardiovascular Pathology and the Society for Cardiovascular Pathology published a consensus document, applied to surgical specimens, to unify criteria. The aim of this work is to assess its application in forensic autopsies. A secondary objective is to study inflammatory changes useful for dating.

Material and methods

Aortic histological preparations of the 54 cases of SD due to aortic rupture/dissection studied between 2019 and 2022 were reviewed.

Results

Medial degeneration was observed in 49 cases (90.8%) (severe in 42.9%). By lesions, the order of frequency was: fragmentation and/or loss of elastic fibres (74.1%), accumulation of extracellular mucoid matrix (61.1%), loss of smooth muscle cell nuclei (48.1%), and collapse of the media (44.4%). Some lesions of the consensus paper could not be assessed. No significant differences were found by age; presence or not of collagenopathies; or bi/tricuspid aortic valves. Granulation tissue or neutrophilic infiltrate was observed in those deceased with pain several days or <24 h before death, respectively.

Conclusion

With the application of the document, lesions in the media are found in > 90% of cases and fundamental lesions can be studied. The inflammatory response to rupture/dissection appears to correlate with the timing of dissection/rupture.