Vascular graft and endograft infections after abdominal aortic aneurysm repair are uncommon but relevant complications, and a systematic review found a lower pooled incidence after endovascular aneurysm repair, or EVAR, than after open surgery, or OS. The review refers to these infections as VGEIs. The finding is a comparison of pooled estimates from the reviewed studies, not proof that one procedure itself caused the difference.
The pooled rates
After EVAR, the pooled incidence of infective events was 0.36 per 100 person-years, with a 95% confidence interval from 0.21 to 0.64. After OS, it was 0.60 per 100 person-years, with a 95% confidence interval from 0.22 to 1.60. Person-years combine the people observed and the time they contributed to the analysis, so these are pooled rates rather than a direct percentage risk for any one patient.
The estimates also came with a warning about consistency. Considerable heterogeneity was identified across the included studies, particularly in the diagnostic criteria used to define VGEI. The reported I-squared statistic was 93.3% for EVAR and 96.3% for OS. In ordinary terms, the studies did not produce closely matching results, so the pooled figures are best read as broad summaries of the evidence.
The review searched PubMed and Scopus for human studies published up to 3 May 2025. Nineteen studies were included. The protocol was conceived in accordance with PRISMA 2020 and registered in PROSPERO on 18 March 2024.
The microbiology was uneven
In the EVAR-related results, Staphylococcus species were the most frequently reported pathogens, with 5 cases, or 12.5%. The same results included 5 polymicrobial cases, involving more than one organism, or 12.5%, and 18 culture-negative cases, meaning no organism was identified in culture, or 45.0%.
Microbiological findings from studies that combined procedures pointed to a broader mix, but they cannot be assigned cleanly to one operation. Those studies reported fungal infections in 16 cases, or 17.8%, Gram-negative bacteria in 15 cases, or 16.7%, and polymicrobial infections in 14 patients, or 15.6%. The available OS data were not sufficient for a separate analysis of which organisms were involved.
What the review could not settle
The analysis also used univariable meta-regression, a study-level test of whether incidence rates were associated with selected characteristics. It found no significant association with mean age, sex distribution or year of publication. That result concerns the available study-level analyses, not whether those factors affect risk in individual patients.
The authors concluded that VGEIs remain uncommon but relevant complications after abdominal aortic aneurysm repair, while the pooled incidence was lower after EVAR than OS. They said future research should use standardized diagnostic criteria and provide more detailed reporting of microbiological causes, especially for open surgery, where the available data did not permit an etiological analysis.
The review reported no funding and no competing interests. The authors also stated that no datasets were generated or analysed during the study.
Paper data and sources
Original title: Incidence and microbiological etiology of vascular graft and endograft infections: a systematic review and meta-analysis.
Authors: Nicholas Geremia, Alberto Enrico Maraolo, Andrea De Vito et al.
Journal/Repository: Infection
Status: Peer-reviewed
First online: 2026-08-21
DOI: 10.1007/s15010-026-02908-6
Original paper · Full text