Purpose The aim of this study was to evaluate the effectiveness of the proposed method of preventive embolization of the internal iliac arteries using a liquid tantalum-containing ethylene vinyl alcohol copolymer. Methods In this nonrandomized clinical study with a retrospective control group, 55 patients with aneurysmal lesions of the infrarenal abdominal aorta participated. In the course of this study, we developed and implemented a method of preventive embolization of the ostia of the internal iliac artery using a liquid tantalum containing ethylene-vinyl alcohol copolymer having viscosity of 34 centipoise. The method was applied in 27 cases in patients with aneurysmal lesions of the infrarenal abdominal aorta with unilateral involvement of the common iliac artery. The maximum follow-up period at the stage of publication of the results was 24 months. Results The proposed method of embolization of the internal iliac artery is accompanied by an absolute risk of developing type II endoleak 0.393 (95% confidence interval: 0.2120–0.5738, p = 0.029); therefore, when using the new technique, there is a decrease in the absolute risk of developing type II endoleak by 39.3%. Conclusion The proposed method of preventive embolization allows to perform reliable occlusion of the internal iliac artery as proximally as possible, which makes it possible to maintain distal blood flow in the internal iliac artery and minimizes the risks of ischemic events.

Among the complications of endovascular abdominal aortic aneurysm repair the most common are the so–called endoleaks - the preservation of blood flow inside an isolated aneurysmal sac. This complication occurs in almost every fourth patient and is the main cause of reinterventions, which makes the late development of this complication one of the urgent problems under discussions. The report presents a clinical case of treatment of a patient with an aneurysm of the infrarenal abdominal aorta with its spread to the common iliac artery using the technique of preventive embolization of the internal iliac artery with application of a liquid tantalum-containing ethylene vinyl alcohol copolymer. All stages of the operation were performed in the catheterization laboratory using a stationary angiographic system. The embolizing material was introduced after implantation of the stent-graft into the target position, through a microcatheter pre-installed at the ostium of the embolizing internal iliac artery. The introduction of a tantalum-containing ethylene vinyl alcohol copolymer after the installation of the stentgraft, under conditions of significant reduction of arterial antegrade blood flow in the lumen of the internal iliac artery, allowed to create a reliable occlusion of the ostium segment of the artery, reduced the risk of migration of embolizing substance into the distal arterial bed.