Results from the Multicenter Study on Aortoenteric Fistulization after Stent Grafting of the Abdominal Aorta (MAEFISTO)

Objective This study investigated the frequency, clinical features, therapeutic options, and results of aortoenteric fistulas (AEFs) developing after endovascular abdominal aortic repair (EVAR). Methods Eight Italian centers with an EVAR program participated in this retrospective multicenter study and collected data on AEFs that developed after a previous EVAR. Results A total of 3932 patients underwent EVAR between 1997 and 2013 at the participating centers. During the same period, 32 patients presented with an AEF during EVAR follow-up, 21 with original EVAR performed for atherosclerotic aneurysmal disease (ATS group) and 11 with the original EVAR performed for a postsurgical pseudoaneurysm (PSA group). The incidence of AEF development after EVAR was 0.46% in the ATS group and 3.9% in the PSA group. Anastomotic PSA as the indication to EVAR (P <.0001) and urgent/emergency EVAR (P =.01) were significantly associated with AEF development. Median time between EVAR and the AEF diagnosis was 32 months (interquartile range, 11-75 months) for the ATS group and 14 months (interquartile range, 10.5-21.5 months) for the PSA group. Among five AEF patients treated conservatively, two (40%) died, at 7 and 15 months, and the remaining three were alive at a median follow-up of 12 months. The AEF was treated surgically in 27 patients, including aortic stent graft explantation in all cases, in situ aortic reconstruction in 14 (52%), and extra-anatomic bypass in 13 (48%). Perioperative mortality was 37% (10 of 27). No additional aortic-related death was recorded in operated-on patients at a median follow-up of 28 months. Conclusions Late AEFs rarely occur during EVAR follow-up, but the risk is significantly increased when EVAR is performed for PSA after previous aortic surgery and EVAR is performed as an emergency. Conservative and surgical treatment of post-EVAR AEF are both associated with high mortality. However, beyond the perioperative period, surgical correction of AEFs appears to be durable at midterm follow-up.