Aneurysm

Aneurysms are focal abnormal dilatation of a blood vessel. They typically occur in arteries; venous aneurysms are rare. Aneurysms may also occur in the heart.

Pathology

Pathological types

1. true aneurysm
2. false aneurysm (or pseudoaneurysm)

Etiology

Atherosclerotic

• atherosclerosis

Non-atherosclerotic

• congenital
• hypertension
• vasculitis
  • fibromuscular dysplasia
  • infection: mycotic aneurysm, syphilis (luetic aneurysm)
• hereditary connective tissue disorders
  • Marfan syndrome
  • Ehlers-Danlos syndrome
  • arterial tortuosity syndrome
• trauma
• iatrogenic
• myocardial infarction: may cause left a ventricular aneurysm
• flow-related (in cerebral AVM, contralateral ICA occlusion, etc.)

Morphology

Morphologically there are two main types of aneurysms. The morphology is not specific for any cause:

1. saccular aneurysm: eccentric, involving only a portion of the circumference of the vessel wall (e.g. cerebral berry aneurysm)
2. fusiform aneurysm: concentric, involving the full circumference of the vessel wall

Occasionally a 3^rd type, serpentine aneurysm has been classified as a separate entity ³.

Treatment and prognosis

Complications

• rupture
• distal thromboembolism
• pressure effects

History and etymology

The word aneurysm traces its roots back to ancient Greek, specifically the word ἀνεύρυσμα (aneurysma), literally translating as an 'aperture'. It is itself a compound construction, derived from two roots, 'ἄνω-' (ano) meaning 'up' and 'εὐρύς-' (eurys), meaning 'wide' ^4,5.

See also

• thoracic aortic aneurysm
• abdominal aortic aneurysm
• popliteal artery aneurysm
• cerebral berry aneurysm
• coronary artery aneurysm
• splenic artery aneurysm
• celiac artery aneurysm
• mycotic aneurysm