Natural Courses of Non-operated and Feeder-clipped Arteriovenous Malformations

Abstract

We examined the natural history of 35 patients with arteriovenous malformations (AVMs) who were treated non-surgically and of 5 who underwent feeder-clipping. The bleeding rate was 4.0% and mortality rate was 0.91% per year with a mean follow-up period of 9.4 years in non-surgically treated group. The bleeding rate was 6.2% and mortality rate was 3.1% per year with a mean follow-up period of 6.5 years in feeder-clipped AVM group. Clipping of feeding arteries for AVM was thought to have no beneficial effect in preventing bleeding from AVMs. AVMs with a history of bleeding tended to rebleed more frequently than those without. Deeply seated AVMs also have a tendency to bleed more frequently than superficially seated AVMs.