Arteriovenous Malformations

Epidemiology

Arteriovenous malformations (AVMs) are congenital lesions with multiple arterial and venous communications. This is in contrast to acquired AV fistulae (usually as a result of trauma), which show only one or two communications. These lesions, although congenital, may present at any age. Curiously, they may appear suddenly following puberty or pregnancy. These lesions are more commonly seen in females.

Clinical Findings

The skin over the lesion appears pink and warm, and the affected side is noticeably enlarged. AVMs may be painful, especially lesions with a mucosal surface, which are prone to bleed or ulcerate. Pulsations are usually evident on inspection or palpation.

Pathology

Clinical correlation is important during microscopic evaluation. AVMs have features of hemangiomas. The diagnosis of AVM is established when arteriovenous connections are detected on serial sections or the presence of intimal thickening in veins is noted.