The Potential Relation Between polytetrafluoroethylene Grafts after Open Reconstructions for Abdominal Aortic Aneurysm and Perigraft Seromas

Background: The presence of sac enlargement after abdominal aortic aneurysm (AAA) open repair, a condition usually called perigraft seroma (PGS), nearly always has a benign behavior. Some theories implicated for PGS formation include coagulation abnormalities, fibroblast inhibition, low-grade infection, or improper graft handling.

Methods: This is a retrospective study including patients treated for AAA in 2 academic vascular surgery departments from 2007 to 2014, where 1 center preferably used polytetrafluoroethylene (PTFE) grafts whereas the preference of other center was mostly Dacron graft. The definition of PGS was conceived as a fluid collection around the graft on CT scan imaging with a radiodensity ≤25 Hounsfield units, reaching at least 30 mm in diameter and beyond the third postoperative month. Analysis was performed between patients with and without PGS.

Results: Seventy-eight patients met the inclusion criteria: 42 received Dacron and 36 PTFE grafts. Twenty-three (29.5%) patients accomplished the PGS diagnosis. Having a PTFE graft was the strongest factor for PGS formation on multivariate analysis. The medium seroma size was 42 mm (range, 30-90.6 mm) and the mean time from AAA repair to PGS detection was 26 months (range, 4-106 months). Three patients of the 23 with PGS required surgical repair, all of them were successfully treated: 2 by endovascular means and the remaining with explantation and Dacron reconstruction.

Conclusions: PGS formation is not an unusual complication after open reconstructions for AAA treatment. This is especially true for PTFE grafts, and thus, closer follow-up is warranted if using this material. Treatment is clearly needed when symptoms appear; however, preventive strategies with either endovascular relining or reopen reconstructions require an individual approach counterbalancing benefits versus risk of the procedures.