Long-term results of Late Open Conversions with Partial or Total Removal of Non-Infected Stent Grafts after Failed Endovascular Aneurysm Repair

Objective: Open surgical conversion after failed EVAR has become more common. Our aim was to compare the short- and long-term results of late open conversions for non-infectious indications with partial or total stent graft removal. Methods: Our study is a retrospective, multicentre observational study of late open conversions performed in five hospitals between January 1997 and June 2024. Patients who underwent a partial or total removal of a stent graft more than 30 days after EVAR for non-infectious indications were included in the analysis and divided into two groups: partial (PC) and total conversion (TC). The primary outcomes were 30-day mortality, 5-year survival and freedom from late complications. The secondary outcomes were peri-operative cardiovascular complications, the length of hospital stay and 5-year freedom from reinterventions and from aneurysm-related death. Results: The analysis included 97 patients: 57 (58.8%) in the PC group, and 40 (41.2%) in the TC group. The 30-day mortality in the PC group was lower compared to the TC group (14.3% vs 24.3%, OR = 0.52, p = .220), although the difference did not reach statistical significance. The estimated 5-year overall survival was similar in the PC and TC groups (58.8% vs 59.8%, p = .726). The patients in the PC group had no infections or thrombosis and a similar freedom from late complications compared to the TC group (81.2% vs 84%, p = .788). A subgroup analysis comparing the preoperative CTA scans and intra-operative observations revealed an occult endoleak in 22 patients (22.7%), and in the 12 patients (12.4%) who underwent surgery for a suspected endoleak, none were identified during the procedure. Conclusions: Partial conversion appears to be non-inferior to total conversion and possibly even safer, with a trend towards lower mortality in the short term. No differences in mortality or complications were found between the groups during long-term follow-up .