Impact of Endograft Fabric on Aneurysm Sac Remodelling after Elective Infrarenal Endovascular Aneurysm Repair.

Abstract

Sac regression after endovascular aneurysm repair (EVAR) is associated with lower mortality and morbidity rates. Most endografts feature an expanded polytetrafluorethylene (ePTFE) or woven polyester body on a nitinol or stainless steel stent. Polyester endografts show fewer type II endoleaks, but more post-implantation inflammatory syndrome (PIS), which may influence abdominal aortic aneurysm (AAA) sac remodelling. This study evaluated whether endograft fabric influences sac remodelling after elective infrarenal EVAR. This was a retrospective, two-centre cohort study including patients with AAA who were electively treated between January 2011 and November 2021 with contemporary infrarenal endografts. Data originated from medical files, duplex ultrasound, and/or computed tomography. The primary endpoint was sac remodelling at one year follow-up. Secondary endpoints included sac remodelling at the latest follow-up, incidence of PIS, AAA-related complications, secondary interventions, endoleak, and death. Among 337 patients who met the inclusion criteria, 256 patients (76.0%) received a polyester endograft and 81 patients (24.0%) received an ePTFE endograft. The median follow-up was 74.7 months (interquartile range 27.8, 107.1). The Endurant II (n = 153; 45.4%), Anaconda (n = 98; 29.1%), and Gore Excluder (n = 65; 19.3%) accounted for 93.8% of cases. Sac remodelling was similar between polyester and ePTFE endografts at one year (p = .17) and at the latest follow-up (p = .81), which was confirmed in multivariable analysis (p = .24 and p = .36, respectively). The Anaconda showed both a higher rate of sac shrinkage and sac expansion at one year follow-up compared with the Endurant II (p = .004). The incidence of PIS was 12.5%, with a higher prevalence with polyester endografts (p = .049). Sac remodelling was similar between patients with and without PIS at one year and at the latest follow-up (both p = .10). Sac remodelling did not differ between polyester and ePTFE endografts after elective infrarenal EVAR with contemporary endografts, but there were intraclass differences within the polyester group. The higher incidence of PIS with polyester endografts had no significant effect on sac remodelling.