Differences in aortic remodeling in patients with type 1a and type 5 endoleak who undergo salvage with fenestrated/branched endovascular aortic repair.

Objective: Aneurysm sac growth following endovascular aortic aneurysm repair (EVAR) is multifactorial. A specific cause of growth (eg, type 1a endoleak [EL1a]) may be present or a specific cause may be absent (no observed endoleak resulting in "endotension" or type 5 endoleak [EL5]). Salvage of EL1a with fenestrated/branched EVAR (F/BEVAR) to obtain supraceliac seal is a viable strategy to achieve sac stability or regression. In patients with EL5, it remains unknown whether F/BEVAR leads to similar sac stability or regression. We sought to determine the incidence rate of sac stability or regression following F/BEVAR for EL1a compared with EL5.

Methods: Prospective databases from two complex aortic centers were retrospectively queried to identify all patients who underwent F/BEVAR for failed EVAR (2015-2024). Patients were categorized to have either EL1a or EL5 based on preoperative computed tomography scan. Pre-, intra-, and postoperative variables were compared between the groups. The primary composite outcome, sac stability (≤5 mm change) or regression (>5 mm decrease), was calculated using the Kaplan-Meier method.

Results: A total of 102 patients (75 with EL1a; 27 with EL5), with a mean age of 78 ± 6.6 years and large aneurysms (71 ± 16.2 mm) were studied; no significant intergroup preoperative characteristic differences were observed. F/BEVAR repairs incorporated 3.8 ± 0.5 target arteries per patient. Fluoroscopy dose, contrast volume, procedure time, blood loss, and technical success were similar between groups. Postoperative complication rates (EL1a: n = 15; 20% vs EL5: n = 4; 15%; P = .77) and 30-day mortality (EL1a: n = 1; 1% vs EL5: n = 2; 7%; P = .17) were similar. The cumulative incidence of sac stability or regression at 4 years was 92% (95% confidence interval [CI], 83%-97%) for EL1a vs 81% (95% CI, 61%-94%) for EL5 (log-rank P = .03). On multivariable analysis, the hazard ratio for sac stability or regression was 1.72 (95% CI, 1.02-2.89; P = .04) for EL1a compared with EL5.

Conclusions: Sac stability or regression can be achieved in most patients with EL1a or EL5 who undergo endovascular salvage with F/BEVAR. However, those treated for EL5 are less likely to achieve sac stability or regression. Additional data are needed to better understand fundamental differences in these subsets of failed EVAR patients and to better guide appropriate salvage therapy.