canine aortofemoral bypass: a new technique for the evaluation of prosthetic implants.

From the Department of Surgery, Section of General Surgery, University of Michigan Medical Center and Veterans Administration Hospital, Ann Arbor, Michigan. Reprint requests to S. M. Lindenauer, M.D., 2215 Fuller Road, Ann Arbor, Michigan 48105. Two canine preparations have generally been used for the experimental evaluation of prosthetic arterial implants. The more popular of these has been replacement of either the distal thoracic aorta or distal abdominal aorta with short segments of prosthetic material. The general acceptance of this method among investigators reflects the ease and rapidity of implantation as well as the negligible operative mortality associated with this procedure. The main criticism of this method has been the inability to implant sufficiently long prosthetic segments to adequately distinguish true arteriogenesis from the intimal ingrowth that normally occurs from each anastomosis. To overcome this drawback, others have proposed the use of longer prosthetic segments by implanting a bypass between the upper thoracic and lower abdominal aorta. First described by McCune and Blades,’ and later popularized by Szilagyi, ~ this method permits the implantation of prosthetic segments, 18 to 26 cm in length allowing evaluation of arteriogenesis in the central portions of the prosthesis. Technical drawbacks associated with this technique limit its widespread application by many investigators. The method is time consuming and is associated with a high operative mortality. The initiation of investigations in this laboratory involving vascular graft infections resulted in the need for an experimental model in which a long segment of arterial prosthesis could be implanted and at the same time