The abdominal aorta is normally smaller than the thoracic aorta, and rupture of the abdominal aorta usually occurs at smaller sizes than in the thorax.

• 腹主动脉一般比胸主动脉小，因此腹主动脉瘤破裂时的尺寸，通常也比胸主动脉瘤破裂时来得小。