Long-Term Results of the Neo-Aorto-Iliac System Procedure as a Compelling Choice for the Treatment of Aortic Infections.

Abstract

Objective: This study aimed to evaluate the short- and long-term clinical outcomes of the Neo-Aorto-Iliac System (NAIS) procedure for primary and secondary aortic infections, focusing on mortality, reintervention, and patency rates over 24 years.

Methods: We performed a retrospective analysis of all consecutive patients who underwent a NAIS procedure at the Centre Hospitalier Universitaire de Québec (CHU de Québec) between January 1, 2000, and August 1, 2024. Collected data included demographic, preoperative, operative, and postoperative outcomes. Kaplan-Meier analysis was used to assess survival and patency rates. Student's t-tests analyzed continuous variables, and Chi-squared or Fisher's exact tests were applied for categorical variables. A P-value <0.05 was considered statistically significant.

Results: 135 patients (75% male) with significant comorbidities underwent NAIS. Primary mycotic aortitis accounted for 35% of cases, while secondary infections comprised 65%, including aortoenteric fistulas (24%) and graft infections (41%). Abdominal pain was the most common initial presentation (44%), and blood cultures were positive in only 33% of cases. Half of the reconstructions were aorto-bi-iliac bypasses, with a mean operative time of 6 hours and 32 minutes (±129 min) and an average blood loss of 3.5 L (±3.0 L). Early complications included acute kidney injury (31%), pneumonia (28%), elevated troponin (24%), anastomotic rupture (8%), and major amputation (4%). In-hospital mortality was 9%, with survival rates of 87%, 68%, 48%, 35% and 15% at 1, 5, 10, 15 and 20 years, respectively. Predictors of mortality included older age, anastomotic rupture, pneumonia, and troponin elevation. Primary patency rates at 1, 5, and 20 years were 93%, 85%, and 83%, while secondary patency rates were 97%, 96%, and 96%. Reintervention was required in 23% of cases, with 5% involving early (less than 30 days) procedures for bleeding. Delayed reinterventions included 22 open surgeries (e.g., femoral angioplasty, anastomosis revision) and 18 endovascular procedures (e.g., iliac stenting, EVAR). The mean follow-up period was 5.2 years, with a maximum of 21.3 years.

Conclusions: The NAIS procedure offers excellent long-term survival, high patency rates, and manageable reintervention rates, supporting its role as the leading treatment option for primary and secondary aortic infections.