When the aorta ruptures spontaneously, rather than as the result of trauma, it is usually in an aortic aneurysm. Rupture of an aortic aneurysm should not be confused with aortic dissection. Aortic rupture describes a tear through all three layers of the aorta, whereas an aortic dissection describes when there is a tear in the tunica intima, allowing blood to separate (dissect) the tunica intima from the tunica media.
This is a companion discussion topic for the original article at https://patient.info/doctor/cardiovascular-disease/ruptured-aortic-aneurysm