Growth factor production after polytetrafluoroethylene and vein arterial grafting: an experimental study.

PURPOSE

Occlusion caused by myointimal hyperplasia appears to be the main reason of late failure of polytetrafluoroethylene (PTFE) arterial bypass grafts. Evidence exists that growth factors are involved in the genesis of myointimal hyperplasia. The aim of this study was to assess the release of platelet-derived growth factor (PDGF) and basic fibroblastic growth factor (bFGF) by PTFE arterial grafts.

METHODS

In 15 inbred Lewis rats a 1 cm long segment of PTFE was interposed at the level of the abdominal aorta. In a control of another 15 Lewis rats in a vein graft was implanted at the level of the abdominal aorta. Animals were killed four weeks after implantation and the tissue was studied in organ culture for release of PDGF AA, PDGF BB, and bFGF.

RESULTS

PTFE grafts released a greater quantity of PDGF AA than did control vein grafts (28 +/- 4 ng/cm2/72 hr vs 7 +/- 2 ng/cm2/72 hr). Similarly, PTFE grafts released a greater quantity of bFGF than did arterial vein grafts (308 +/- 22 ng/cm(2)/72hr vs 204 +/- 20 ng/cm2/72 hr).

CONCLUSIONS

We conclude that PTFE arterial grafts released a high quantity of growth factor, which could explain, in part, the occurrence of distal anastomotic myointimal hyperplasia.