Which of the following statements about arteriovenous fistula are correct?

A. The local features characteristic of an arteriovenous communication are demonstrated by the presence of a thrill and bruit with aneurysmal dilatation.

C. The most common type of arteriovenous fistula is iatrogenic, created for vascular access.

DISCUSSION: Local features characteristic of an arteriovenous fistula include a thrill and bruit at the site of the fistula associated with aneurysmal dilatation. Simple ligation of feeding vessels often leads to vascular insufficiency of the peripheral vascular bed secondary to drainage of the flow via collateral circulation. Repair of the artery and vein is considered the optimal therapy. If this is not possible, ligation of the feeding artery and vein proximally and distally can be performed if sufficient collateral circulation has developed, which generally takes months or more after the fistula develops. Branum's or Nicoladoni's sign is a decrease in the heart rate following compression of the fistula.