Purpose: Aortic endograft infection (EI) can result in potentially life-threatening vascular complications. Unfortunately, it is difficult to obtain a correct diagnosis at an early stage in many patients. This report aims at validating the use of [18F] FDG PET/CT imaging for suspected endograft infections in a prospectively collected cohort of patients treated with EVAR and TEVAR.
Materials and methods: During a 14-year period, 366 patients required aortic stent graft. All procedures were performed electively, except for one patient. Among these 366 patients, eleven patients (3%) were suspected to have aortic EI. Contrast-enhanced CT and FDG PET/CT were performed in all 11 patients. Medical charts and imaging were analysed for these 11 cases, with initial positive CT.
Results: The final diagnosis of EI was established in seven (1,9%) based on clinical features, laboratory investigations and a significant [18F] FDG uptake in the aortic graft as well as the aortic wall. The median time from the initial EVAR/TEVAR to diagnosed infection was 180 days. During follow-up, the seven patients had a second PET/CT that was compared with the initial evaluation, decreased uptake was correlated with clinical improvement.
Conclusions: Contemporary diagnostic imaging for a potentially lethal endograft infection lacks precision, this observational study illustrates the potential clinical value of [18F] FDG PET/CT in the management of aortic EI. [18F] FDG PET/CT constitutes an imaging modality able to confirm the diagnosis, monitor disease progression as well as the effect of pharmaceutical treatment and detect relapse.
Keywords: Aortic graft infection; abdominal aortic aneurysm; endograft; endovascular; imaging; positron emission tomography.