Inferior mesenteric artery as outflow vessel in endoleaks after abdominal aortic stent-graft implantation: 36-month follow-up CT study

The aim of this study was to determine the role of the inferior mesenteric artery (IMA) as an outflow vessel in endoleaks after abdominal aortic stent -graft implantation. Forty consecutive patients in whom abdominal aortic an eurysms (AAA) had been treated with stent-graft implantation were evaluated retrospectively. Spiral-CT examinations and angiographies up to 36 months after implantation were analyzed. In 29 (73%) of the 40 patients the IMA wa s perfused prior to implantation. In 5 (17%) of these 29 cases, the artery remained perfused after stent-graft insertion. In all 5 cases, endoleaks we re detected, however, in none of these cases was the IMA the sole cause. In 3 of these 5 cases, angiography showed antegrade flow in the IMA. Implanta tion of extension stent grafts caused thrombosis of the aneurysmal sac and the IMA. There were no secondary endoleaks caused by the IMA at the 36-mont h follow-up examinations. The majority of IMAs which are patent prior to in tervention occlude after successful stentgraft insertion. In cases with lea ks and angiographically proven antegrade flow in the IMA, implantation of e xtension stent grafts is a therapeutic alternative to embolization. In this study, the IMA was not responsible for secondary endoleaks.