Outcomes of Endovascular Repair for Infected Native Thoracic Aortic Aneurysms: A Japanese Multicentre Study

Objective: Infected native thoracic aortic aneurysms (INTAAs) are life threatening emergencies. Although open surgery remains the definitive treatment, thoracic endovascular aortic repair (TEVAR) is a less invasive option for high risk patients. However, its long term efficacy in controlling infection is unclear. This study evaluated the outcomes of TEVAR for INTAAs in a Japanese multicentre cohort. Methods: This was a retrospective multicentre study using data collected from the Japanese Committee for Stentgraft Management (JACSM) registry (2016 – 2018). Patients were included on the basis of strict criteria requiring clinical, laboratory, and imaging evidence of infection. The primary outcome was infection related complications. Secondary outcomes were overall survival and freedom from infected aneurysm related death. Results: Seventy-eight patients (mean age, 75.6 years; 72% men) met the inclusion criteria. Over a median 2.5 year follow up, infection related complications occurred in 24 patients (31%). The median duration of antimicrobial therapy was statistically significantly shorter in patients who developed complications than in those who did not (32.5 days vs. 162 days; p = .027). The overall survival rate was 92% at 30 days and 63% at five years. Infection with methicillin resistant Staphylococcus aureus (MRSA) and pre-operative fever (≥ 38°C) were independent predictors of poor outcomes. Conclusion: TEVAR provides successful acute stabilisation for high risk patients with INTAA, but late treatment failure remains a notable challenge. This study identified two key independent predictors of poor outcomes: infection with MRSA and pre-operative fever (≥ 38°C). Furthermore, the findings suggest that an insufficient duration of antimicrobial therapy contributes to treatment failure. Therefore, the success of TEVAR is critically dependent on a robust, multidisciplinary strategy that prioritises prolonged infection control, especially in patients presenting with these high risk features.