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 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