IYSC10 - Aneurysm-Sac Dynamics and Mid-Term Outcomes Following Fenestrated Endovascular Aneurysm Repair After Previous Endovascular Aneurysm Repair

Objectives: Research has shown that fenestrated endovascular aneurysm repair (FEVAR) represents a feasible option for aortic repair after prior EVAR, due to improved perioperative outcomes. However, little is known regarding the durability of FEVAR as rescue of failure. Since aneurysm sac evolution is an important marker for success after endovascular aneurysm repair, the aim of our study was to examine aneurysm sac dynamics of FEVAR after prior EVAR as well as mid-term outcomes.

Methods: We included all consecutive patients undergoing FEVAR for complex abdominal aortic aneurysms (cAAA) from 2008-2021 at two large hospitals in the Netherlands. FEVARs after open aortic repair were excluded, and patients were subsequently categorized into primary FEVAR and FEVAR after EVAR. Outcomes included five-year secondary aneurysm-related procedures and mortality. One-year aneurysm sac dynamics (regression/stable/expansion, based upon 5% change compared with 30-day volume), and sac dynamics over time were evaluated between the groups with imaging data. Analyses were done using Kaplan-Meier methods, multivariable cox-regression analysis, Chi-square tests, and linear mixed effect models.

Results: We identified 196 FEVAR patients of which 27% patients (n=53) had a prior EVAR. Patients with a prior EVAR were significantly older (78 years [±6.7] vs. 73 years [±5.9], p<.001). FEVAR after EVAR was associated with higher risk of developing secondary aneurysm-related procedures within 5 years (HR: 2.62; [95%CI: 1.06-6.50], p=.04) compared to primary FEVAR. Moreover, patients with a prior EVAR showed significantly lower rates of sac regression and higher rates of sac expansion at one-year compared to primary FEVAR patients (42% sac expansion vs. 5% sac expansion, p<.001). Sac dynamics over time showed the same results, sac growth for FEVAR after EVAR and sac shrinkage for primary FEVAR (p <.001). (Fig 1). Finally, there were no significant differences in five-year mortality between the groups (HR: 0.67; [95%CI: 0.30-1.49], p=.33).

Conclusions: Despite successful proximal extension and relining, FEVAR after EVAR patients had higher rates of sac expansion at one-year and needed more secondary procedures than primary FEVAR patients although this did not seem to effect survival. Future studies will have to assess whether FEVAR after EVAR is a valid intervention following failed infrarenal EVAR, and the underlying process that drives aneurysm sac growth after successful FEVAR after EVAR.