Retrospective Cohort Study on EVAR Open Surgical Conversion: Focus on Endoleaks With Wrong Preoperative Categorization.

Background: Late open conversion (LOC) following endovascular aneurysm repair (EVAR) is a rare complication with a high morbidity and mortality and is often proposed as the last line of treatment after failure of endovascular reintervention of any type. This study aimed to highlights the limitations of EVAR follow-up imaging in characterizing endoleaks, which may contribute to the failure of endovascular reinterventions and lead to LOC.

Methods: This retrospective cohort study recruited all EVAR implanted in Amiens University Hospital (France) between January 2008 and December 2022. Elective LOC was defined as surgical conversion >1 month after EVAR. The primary endpoint was the rate of wrong categorization of endoleaks by follow-up exams before LOC. Secondary endpoints were the morbidity and the mortality associated with LOC.

Results: Seven hundred eight EVARs were performed in our institution, 30 required elective LOC. Twenty-five of them were treated for sac enlargement due to an endoleak (83.3%) (all types). Wrong categorization of the endoleak was noted in 13 patients (52.2%). Twelve of these recategorizations involved the preoperative diagnosis of a type II endoleaks (92.3%). The change in categorization in 7 out of 12 cases (58%) was in favor of a type I endoleak, other recategorization included 1 type III (8%) and 4 type IV (33%). One patient died during the 30-day postoperative period and 7 patients (28%) presented a major complication; the median length of stay was 13 days (interquartile range 9-21).

Conclusions: Routine follow-up examinations such as angioscanner and contrast Doppler ultrasound appear to be limited in their ability to categorize the type of persistent endoleak, which may increase the number of patients requiring LOC. New precision diagnostic imaging techniques, such as dynamic examinations, need to be developed to limit the need for LOC.