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

Objective Fenestrated endovascular aneurysm repair (FEVAR) represents a feasible option for aortic repair after endovascular aneurysm repair (EVAR), due to improved peri-operative outcomes compared with open conversion. However, little is known regarding the durability of FEVAR as treatment of failed EVARs. Since aneurysm sac evolution is an important marker for success after aneurysm repair, the aim of the study was to examine mid-term outcomes and aneurysm sac dynamics of FEVAR after prior EVAR. Methods Patients undergoing FEVAR for complex abdominal aortic aneurysms from 2008 to 2021 at two hospitals in The Netherlands were included. Patients were categorised into primary FEVAR and FEVAR after EVAR. Outcomes included five year mortality, one year aneurysm sac dynamics (regression/stable/expansion), sac dynamics over time, and five year aortic related procedures. Analyses were done using Kaplan–Meier methods, multivariable Cox regression analysis, chi-square tests, and linear mixed effect models. Results In total, 196 patients with FEVAR were identified, of whom 27% (n = 53) had a prior EVAR. Patients with prior EVAR were significantly older (78 ± 6.7 years vs. 73 ± 5.9 years, p < .001). There were no significant differences in mortality. FEVAR after EVAR was associated with higher risk of aortic related procedures within five years (hazard ratio [HR] 2.6; 95% confidence interval [CI] 1.1 – 6.5, p = .037). Sac dynamics were assessed in 154 patients with available imaging. Patients with a prior EVAR showed lower rates of sac regression and higher rates of sac expansion at one year compared with primary FEVAR (sac expansion 48%, n = 21/44, vs. 8%, n = 9/110, p < .001)). Sac dynamics over time showed similar results, sac growth for FEVAR after EVAR, and sac shrinkage for primary FEVAR (p < .001). Conclusion FEVAR after EVAR showed high rates of sac expansion and needed more secondary procedures than patients with primary FEVAR, although this did not affect mid-term survival. Future studies will have to assess whether FEVAR after EVAR is a valid intervention, and the underlying process that drives aneurysm sac growth following successful FEVAR after EVAR.