Intraoperative localization of intestinal arteriovenous malformation.

Intestinal arteriovenous malformation (AVM) is an uncommon cause of gastrointestinal hemorrhage and is difficult to diagnose. Selective visceral angiography is essential to make the diagnosis and to localize the lesion. We treated two patients in whom AVMs of the small intestine were located by means of arteriography and intraoperative selective mesenteric venous pressure and PO2 measurements. The local venous return from an intestinal AVM is characterized by elevated venous pressure and PO2 levels compared with the venous drainage of adjacent normal intestine.