Australia & New Zealand Society of Vascular Surgeons

Introduction Vein graft stenosis is believed to be entirely due to intimal hyperplasia. Approximately 10-30% of infrainguinal bypass vein grafts fail within 2 years requiring further intervention. Ionizing radiation has been used with some success to reduce coronary re-stenosis rate after angioplasty. The aetiology of restenosis in the post-angioplasty vessels is thought to be due to intimal hyperplasia and vascular remodeling from the injury sustained to the arterial wall during angioplasty. We postulated that irradiating the vein graft immediately prior to implantation as a bypass graft should inhibit proliferation of smooth muscle cells and prevent the development of graft stenosis. Methods Thirteen patients were involved in a pilot study where vein grafts were harvested and irradiated with 10 Gy ionizing radiation and then implanted. A variety of parameters were measured including early duplex Doppler ultrasound assessing patency. Results All grafts had very good early patency rates. Eight of 12 (66.7%) grafts failed suddenly with no warning after 6 months. The study was suspended hereafter pending review. Conclusions Our study suggests that ionizing radiation may be able to prevent intimal hyperplasia but may have a detrimental effect on the long-term outcome. This study raises significant concerns about using ionizing radiation to reduce intimal hyperplasia in vein bypass grafts.