VESS05 - Primary Aortic Endograft Infections Have Worse Outcomes Compared to Infections Involving Aortic Surgical Grafts or Primary Mycotic Aortic Infections

Objectives: Aortic infection is associated with high morbidity and mortality, but the outcomes of prosthetic (surgical or endovascular) grafts compared to primary aortic infections are poorly defined. This large single-center retrospective study aims to compare the outcomes of primary and prosthetic aortic graft infections.

Methods: Patients diagnosed with primary or infected aortic grafts between January 2000 and December 2022 were included. Patients were group based on the infection type (primary, surgical graft and endograft). Baseline demographics, symptoms, imaging, interventions, and outcomes were evaluated. Primary outcomes included overall and reintervention-free survival. Kaplan-Meier survival and Cox proportional hazards analysis were performed.

Results: A total of 145 patients presented during the study period with infections of the native aorta (34.5%) and aortic graft (65.5%). Baseline characteristics and treatments are summarized in Table 1. In-hospital mortality (36.7% vs. 15.4% vs. 10%, p=0.01) and 30-day complication rates (67% vs. 40% vs. 38%, p=0.03) were highest among endografts, followed by surgical grafts, and lowest among primary infections respectively. Primary aortic infections had the highest 30-day, 1-year, and 5-year survival on Kaplan Meier analysis compared to surgical and endograft infections (Figures 1). Reintervention-free survival was also highest in primary infections at 1 and 5 years (log-rank p< 0.001), while no difference was found at 30 days. On multi-variate analysis, infected surgical grafts and endografts were associated with a significantly higher 30-day mortality (HR 9.18, p=0.015 and HR 7.58, p=0.02 respectively). Visceral artery involvement or isolated groin infections did not influence mortality at any timepoint nor did treatment type (in-situ repair vs. extra-anatomic vs. endovascular), while gram-positive tissue cultures were associated with higher 30-day and 1-year mortality (HR 17.6, p=0.01 and HR 4.14, p=0.004 respectively) when compared to patients who had no growth on tissue cultures. There was no difference in the duration of intravenous antibiotic treatment between groups (42 vs. 45 vs. 44 days; p=0.84).

Conclusions: Infected aortic endografts have lower short and long-term survival independent of treatment type as well as a lower rate of long-term intervention-free survival when compared to surgical graft and primary aortic infections. Gram positive intra-op cultures were associated with increased mortality. Predictors of endograft infection need to be determined to minimize complications and careful consideration is necessary before employing endovascular interventions if there is concern an underlying mycotic process.