Inferior mesenteric artery embolization before endovascular aneurysm repair: Technique and initial results

PURPOSE: To report a single center's technique and initial results in the preoperative embolization of the inferior mesenteric artery (IMA) before endovascular aneurysm repair (EVAR). MATERIALS AND METHODS: Over a 3-year period, 102 patients at a single clinical site, including 86 men and 16 women aged 54-93 years (mean, 75 years), were found to have a patent IMA on computed tomographic (CT) angiography before EVAR. Coil embolization was performed after subselective catheterization with use of microcoils placed in the IMA proximal to the origin of the left colic artery. All patients in whom the IMA was visualized on flush aortography and successfully accessed underwent embolization. One month and 6 months after surgery, results in this cohort were retrospectively compared with those from a similar group of patients who underwent EVAR during the same period. These patients had patent IMAs on preoperative CT angiography but did not undergo embolization as a result of nonvisualization during flush aortography. All patients underwent EVAR with bifurcated modular devices with proximal transrenal fixation. All patients underwent postoperative follow-up with multiphase CT angiography to detect the presence of endoleak. Six-month follow-up data were available for 18 patients who underwent embolization and 54 patients who did not. Change in sac diameter was compared in these patients. RESULTS: Embolization was technically successful in 30 of 32 patients (94%) in whom it was attempted. There were no complications. At 1-month follow-up, five of 30 patients in the embolization group were noted to have a type 11 endoleak (17%). None of the endoleaks in this group were related to the IMA. The group with patent IMAs who did not undergo preoperative embolization had a 42% incidence of type II endoleak (P < .05). At 6 months after surgery, three of 18 patients who had undergone embolization (17%) had a type II endoleak, compared with 26 of 54 in the other group (48%; P < .05). Among the patients in whom 6-month data were available, mean changes in sac diameter were -5.2 mm (range, -24 to 2 mm) in the embolized group and -2.1 mm (range, -19 to 8 mm) in the nonembolized group. CONCLUSION: These initial results demonstrate that embolization of the IMA with subselective microcoils before EVAR is a safe and effective procedure to reduce the incidence of type 11 endoleaks. The data also suggest that preoperative embolization of the IMA is associated with greater shrinkage of aneurysm sac diameter at 6 months.