Present status of endovascular brachytherapy in peripheral arteries

Abstract

Background: Peripheral artery disease based on atherosclerosis is one of the major problems in angiology. Endovascular brachytherapy has shown to be a promising new treatment method for prevention of restenosis after femoropopliteal angioplasty.

Method: Brachytherapy for peripheral arteries is performed by using an iridium-192 gamma source delivered with a remote controlled afterloading unit. Semiflexible 5F radiation catheter without centering possibility and specially designed 7F centering radiation delivery catheter with segmented balloons are available. After angioplasty patient is transported to the brachytherapy unit equipped with specific shielded walls. For treatment planning the whole length of intervention (interventional length = IL) plus safety margins is assumed to be the target. Dose should be related to a certain radial depth (2 mm) from the vessel lumen into vessel wall as proposed in the EVA GEC ESTRO Recommendations. Treatment planning is performed based on the vessel lumen diameter, IL safety margins and reference isodose length (RIL).

Results: First clinical experience with endovascular brachytherapy was obtained in Frankfurt and showed significant improvement of arterial patency even after a long follow-up period. The Vienna-2 study was the first prospective, randomized trial proofing 48% relative reduction of restenosis in the brachytherapy arm. The results of ongoing trials using centering catheter (Vienna-3, PARIS) are soon expected and will definitely determine the role of endovascular brachytherapy for restenosis prevention after angioplasty.