True aneurysm

In a true aneurysm, the aneurysm is bound by all three layers of the vessel wall (intima, media and adventitia). The wall may be attenuated. The risk of rupture is proportional to the size of the aneurysm.

Pathology

Etiology

• congenital
• atherosclerosis
• hypertension
• vasculitis
• hereditary connective tissue disorders (Marfan's syndrome, Ehlers-Danlos syndrome)
• fibromuscular dysplasia
• syphilis
• myocardial infarction: may cause left ventricular true aneurysm