Hamid Gavali: On Complications After Aortic Surgery: With A Focus On Aortic Graft and Endograft Infections

Abstract

Aortic surgery has transformed with the widespread adoption of endovascular repair, reducing perioperative morbidity and mortality, particularly in older and frail patients, but introducing new complications and long-term challenges. This thesis investigated outcomes following complications of aortic surgery, focusing on critical care requirements after abdominal aortic aneurysm (AAA) repair and the epidemiology, management, and outcomes of aortic graft and endograft infections (AGI).

Study I analysed a single-centre retrospective cohort of 707 AAA repairs between 1999 and 2013. Prolonged intensive care unit length of stay (ICU LOS) decreased over time while the frequency of endovascular repair increased. Open repair and rupture were the strongest predictors of prolonged ICU stay. Prolonged ICU LOS  was associated with increased short-term mortality, but long-term survival among 90-day survivors was comparable.

Study II compared extra-anatomical bypass (EAB) and in situ reconstruction (ISR) following radical surgical treatment of abdominal AGI in a nationwide Swedish cohort of 126 patients between 1995 and 2017. No differences were observed in short- or long-term survival or reinfection rates between EAB and ISR. Prolonged antimicrobial therapy (>3 months) was independently associated with improved long-term survival.

Study III evaluated semi-conservative (SC) strategies versus radical surgery (RS) for abdominal AGI in 169 patients in the same nationwide cohort. Short-term survival was similar between groups, but SC was associated with a higher risk of recurrent infection, particularly in graft-enteric fistulae. Differences in long-term survival were attenuated after adjustment for comorbidities.

Study IV analysed aortic endograft infections (AeGI) after complex endovascular aortic repair (cEVAR) between 2010 and 2024 in a single center setting. AeGI incidence was higher than after standard EVAR. Infectious index pathology and late aortic reinterventions were independently associated with AeGI. Outcomes were acceptable without secondary fistulae but poor when fistulae were present.

In conclusion, while endovascular repair has reduced early postoperative complications and critical care requirement after aortic surgery, AGI remains a major challenge. AGI outcomes in the studied cohorts were driven less by surgical techniques alone and more by patient and anatomical factors, underscoring the need for individualised, multidisciplinary decision-making.