Clinical outcomes of the neoaortoiliac system procedure stratified by infection subtype

Objective Aortic infections comprise a heterogeneous group of high-risk conditions, including primary mycotic aneurysm, prosthetic graft infection, and aortoenteric fistula (AEF), each associated with distinct clinical presentation, operative complexity, and early hazard. Although the Neo-Aorto-Iliac System (NAIS) procedure is recognized as a durable in situ reconstructive option for aortic infection, it remains unclear whether outcomes differ according to infection subtype. This study evaluated perioperative and long-term outcomes after NAIS reconstruction stratified by underlying diagnosis. Methods A retrospective single-center cohort study was conducted of all consecutive patients who underwent NAIS reconstruction for aortic infection at a tertiary referral center between 2000 and 2024. Patients were stratified into three groups: primary mycotic aneurysm, prosthetic graft infection, and AEF. The primary outcome was overall survival. Secondary outcomes included 30-day mortality, postoperative complications, graft patency, and freedom from reintervention. Kaplan–Meier analysis was used to estimate survival and patency, and multivariable regression was performed to identify independent predictors of mortality and reintervention. Results Among 135 patients, 47 (35%) had a primary mycotic aneurysm, 55 (41%) suffered from a prosthetic graft infection, and 33 (24%) presented with an AEF. Operative complexity differed significantly between groups, with longer procedures and greater transfusion requirements in patients with AEF and graft infection. Overall, 30-day mortality was 9% but was highest in patients with AEF (21.2% vs 5.5% for graft infection and 4.3% for mycotic aneurysm; P=.016). Overall survival at 1, 5, and 10 years was 87%, 68%, and 48%, respectively, with no significant difference between subtypes on Kaplan–Meier analysis. In adjusted analyses, age and chronic kidney disease were independently associated with mortality. Although AEF was associated with increased mortality in the baseline multivariable model, this association was attenuated after additional adjustment for postoperative complications. Primary patency remained excellent at 93%, 85%, and 83% at 1, 5, and 20 years, respectively, with no significant differences between groups. Reintervention was required in 23% of patients and was more frequent in prosthetic graft infections; on multivariable analysis, graft infection was independently associated with reintervention. Conclusions NAIS reconstruction provides durable long-term survival and graft patency across the major subtypes of aortic infection. Although AEF is associated with greater perioperative risk and prosthetic graft infection results in a higher reintervention burden, infection subtype does not appear to compromise the long-term durability of the reconstruction itself.