In this experimental study, infrarenal part of the vena cava inferior was replaced with a prosthetic PTFE graft either with rings or without rings. Grafts at 5 cm length and 8 mm diameter were chosen. Terminoterminal anastomoses were performed by using continuous stitching with 6-0 prolene suture material on all the dogs.

Arteriovenous fistula was performed to half of the dogs in both groups. The aim was to increase blood flow and pressure through the grafts. Patency rates for 45 days were compared. There was no patent graft at the end of the 45 th day.

However, microscopic examinations have shown neointimal development inside the graft in three cases (33.3%). This was the proof of the graft patency during this period which is approximately three weeks.

There was no difference between patency of the PTFE grafts either with rings or without rings.

These findings led us to the conclusion that prosthetic graft replacement of infrarenal inferior vena cava will result with thrombosis in a short period of time and is not a satisfactory procedure in long term.