Blunt thoracic aortic injuries: an autopsy study.

OBJECTIVE

The objective of this study was to identify the incidence and patterns of thoracic aortic injuries in a series of blunt traumatic deaths and describe their associated injuries.

METHODS

All autopsies performed by the Los Angeles County Department of Coroner for blunt traumatic deaths in 2005 were retrospectively reviewed. Patients who had a traumatic thoracic aortic (TTA) injury were compared with the victims who did not have this injury for differences in baseline characteristics and patterns of associated injuries.

RESULTS

During the study period, 304 (35%) of 881 fatal victims of blunt trauma received by the Los Angeles County Department of Coroner underwent a full autopsy and were included in the analysis. The patients were on average aged 43 years±21 years, 71% were men, and 39% had a positive blood alcohol screen. Motor vehicle collision was the most common mechanism of injury (50%), followed by pedestrian struck by auto (37%). A TTA injury was identified in 102 (34%) of the victims. The most common site of TTA injury was the isthmus and descending thoracic aorta, occurring in 67 fatalities (66% of the patients with TTA injuries). Patients with TTA injuries were significantly more likely to have other associated injuries: cardiac injury (44% vs. 25%, p=0.001), hemothorax (86% vs. 56%, p<0.001), rib fractures (86% vs. 72%, p=0.006), and intra-abdominal injury (74% vs. 49%, p<0.001) compared with patients without TTA injury. Patients with a TTA injury were significantly more likely to die at the scene (80% vs. 63%, p=0.002).

CONCLUSION

Thoracic aortic injuries occurred in fully one third of blunt traumatic fatalities, with the majority of deaths occurring at the scene. The risk for associated thoracic and intra-abdominal injuries is significantly increased in patients with thoracic aortic injuries.