Secondary aortoenteric fistula: a narrative review of the view of the surgeon

Aortoenteric fistula (AEF) is defined as the abnormal communication between the aorta and the gastrointestinal tract. AEFs are divided into primary and secondary usually after abdominal aortic aneurysm (AAA) recovery and are a rare but quite dangerous cause of gastrointestinal bleeding that the general surgeon may face during his/her career. Secondary AEF was first described in 1953 to a 44-year-old woman 3 months after an AAA operation. This review presents the role of the surgeon in the management of secondary aortoenteric fistulas. AEFs are a rare but fatal gastrointestinal bleeding cause that the general surgeon may be asked to manage. Diagnosis requires the combination of strong clinical suspicion and the presence of a history of AAA surgery. Although a vascular surgery case, general surgeons play a role in choosing the technique of restoring the intestinal tract, which seems to be significantly related to subsequent morbidity and mortality.

Editor's Choice - Management of Secondary Aorto-enteric and Other Abdominal Arterio-enteric Fistulas: A Review and Pooled Data Analysis

OBJECTIVES

To compare management strategies for secondary abdominal arterio-enteric fistulas (AEFs).

METHODS

This study is a review and pooled data analysis. Medline and Scopus databases were searched for studies published between 1999 and 2015. Particular emphasis was given to short- and long-term outcomes in relation to AEF repair type.

RESULTS

Two hundred and sixteen publications were retrieved, reporting on 823 patients. In-hospital mortality was 30.7%. Open surgery had higher in-hospital mortality (246/725, 33.9%), than endovascular methods (7/98, 7.1%, p < .001, OR 6.7, 95% CI 3-14.7, including staged endovascular to open surgery, 0/13, 0%). In-hospital mortality after graft removal/extra-anatomical bypass grafting was 31.2% (66/226), graft removal/in situ repair 34% (137/403), primary closure of the arterial defect 62.5% (10/16), and for miscellaneous open procedures 41.3% (33/80), p = .019. Among the subgroups of in situ repair, homografts were associated with a higher mortality than impregnated prosthetic grafts (p = .047). There was no difference in recurrent AEF-free rates between open and endovascular procedures. Extra-anatomical bypass/graft removal and in situ repair had a lower AEF recurrence rate than primary closure and homografts. Late sepsis occurred more often after endovascular surgery (2-year rates 42% vs. 19% for open, p = .001). The early survival benefit of endovascular surgery was blunted during follow-up, although it remained significant (p < .001). Within the in situ repair group, impregnated prosthetic grafts were associated with the worst overall and AEF related mortality free rates and vein grafts with the best. No recurrence, sepsis, or mortality was reported following staged endograft placement to open repair after a mean follow-up of 16.8 months (p = .18, p = .22, and p = .006, respectively, compared with patients in other groups).

CONCLUSIONS

Endovascular surgery, where appropriate, is associated with better early survival than open surgery for secondary AEFs. Most of this benefit is lost during long-term follow-up, implying that a staged approach with early conversion to in situ vein grafting may achieve the best results in selected patients.