Endovascular aortic stent for thoracic and abdominal aortic aneurysm: imaging consequences and complications

Background: Endovascular stent-graft implantation has been used as an alternative to conventional open surgery in treatment of aortic aneurysm. Computed tomographic angiography (CTA) has been requested for follow-up and evaluation of aortic stent complications. Objective: Find the incidence of endovascular aortic stent complications and analyze the CTA features of postendovascular aortic stent consequences. Methods: Two radiologists reviewed CTA images of 635 patients who attended King Chulalongkorn Memorial Hospital between Sep 1, 2003 and Aug 31, 2008. Thirty-eight patients had endovascular aortic stent installation with 95 CTA images. The incidence of endovascular aortic stent complications, the image appearances including consequences and time-interval of endoleak were analyzed. Results: There were 23 thoracic aortic stents, 10 abdominal aortic stents and five combined stents for thoracic and abdominal aortic aneurysms. Twenty-eight cases had aortic stent complications (73.7%). Two cases had immediately post procedural complication of groin hematomas (7.1%). Ten patients had more than one finding. Findings of the stent-graft complications were as follows: 19 endoleaks, 15 stent thrombosis, five stents without covered-dissection, two stent kinkings, two iatrogenic focal aortic dissection, two air within aneurysm after stent installation and one spreading infected aortitis. The most common complication was endoleaks (53.6%), which could progress, be persistent or resolvable. Time-interval to detect endoleak was between 1 and 464 days. Conclusion: CTA can be used as modality of choice in demonstration of stent location, consequences, and complications. The stent complication was still high in the first five-year experience.