A medical device that can be wrapped around a segment of an artery downstream of an arteriovenous fistula. The wrap, when used in this manner, creates a stenosis for reducing retrograde flow at the fistula. Sutures are positioned in holes present in the upper and lower halves or connecting ends of the wrap, after which the sutures are pulled to oppose the two sides in order to create a stenosis. When the surgeon is satisfied that the stenosis is appropriate, the sutures are tied in place.