Minimal traumatic aortic injuries: meaning and natural history.

OBJECTIVE Minimal aortic injuries (MAIs) are being recognized more frequently due to the increasing use of high-resolution diagnostic techniques. The objective of this case series review was to report the clinical and radiological characteristics and outcomes of a series of patients with MAI. METHODS From January 2000 to December 2011, 54 major blunt trauma patients were admitted to our institution with traumatic aortic injuries. Nine of them presented with MAI, whereas the remaining 45 patients suffered a significant aortic injury (SAI). RESULTS MAIs accounted for 17% of the overall traumatic aortic injuries in our series. Major trauma patients with MAI and SAI were similar regarding the presence of severe associated non-aortic injuries and the expected mortality calculated by injury severity score, revised trauma score and trauma injury severity score. There were no statistically significant differences in in-hospital mortality between MAI (22.2%) and SAI (30.2%). No death in the MAI group was aortic related, whereas five deaths in the SAI group were caused by an aortic complication. The survival of MAI patients was 77.8% at 1 and 5 years. There was no late mortality among MAI patients. The survival of SAI patients was 69.7% at 1 year and 63.6% at 5 and 10 years. None of the seven surviving patients with MAI presented a progression of the aortic injury. In six patients, the intimal tear completely healed in imaging controls, whereas one patient developed a small saccular pseudoaneurysm. CONCLUSIONS Blunt traumas presenting MAI are as severe as traumas that associate SAI and present similar in-hospital mortality. In contrast to SAI traumas, in-hospital mortality due to MAI is not usually related to the aortic injury, so these injuries are more amenable to a conservative management. It is mandatory to perform a close imaging surveillance to detect early any potential adverse evolution of an MAI. Nevertheless, a balance must be struck between a close serial imaging surveillance and the potentially detrimental effects of obtaining high-resolution additional images.