Open Conversions and Semiconversions for Late Endoleaks After EVAR: A 22-year Multicentre Experience

Introduction: The majority of late endovascular abdominal aneurysm repair (EVAR) complications are usually managed by endovascular means. Nevertheless, a late open conversion (LOC) or semi-conversion (SC) is sometimes required. The aim of this study is to report the technical aspects of a multicentre experience of LOC and SC, and to compare early and long-term outcomes of these two treatments. Methods: All-LOC and SC performed from 1996 to 2018 in 12 vascular centres were reviewed. LOC was defined as a total or partial endograft explantation >30 days after the initial EVAR; whereas open or laparoscopic surgery for endoleak (EL) correction with complete endograft preservation was considered SC. Conversions performed for endograft infection or thrombosis were excluded. Patients' demographics, time elapsing from EVAR, indication for conversion, operative technique (endograft removal, type of reconstruction or EL correction), 30-day and in-hospital mortality were analysed. Long-term survival was evaluated by Kaplan-Meier method. Results: Two hundred and twenty-four patients were included: 195 underwent LOC, 29 SC. Mean age at conversion was 75.2±7.7 years; 88% male. Patients underwent LOC or SC after a median of 45.9 months (range: 1.2-193.5). Reasons for LOC were: 61% type I EL, 24.1% type II EL, 7.2% type III EL, 7.7% endotension. Indications for SC were: 69% type II EL, 31% type I EL. Reconstructions in case of LOC were performed with dacron grafts in 189/195 cases, axillo-bifemoral bypass in 3/195, cryopreserved arterial allografts in 2/195, and autologous superficial femoral vein in 1/195. SC were performed as follows: 13/29 sacculotomy and lumbar/inferior mesenteric artery (IMA) ligation, 7/29 hypogastric and/or IMA ligation, 6/29 sacculotomy associated with neck banding, 3/29 neck banding. Overall 30-day mortality was 8.5% (19/224), in-hospital mortality 12.1% (27/224). In-hospital mortality rates were significantly higher for patients undergoing LOC (27/195, 13.9%) compared to SC (0/29, P=.03). The estimated 1-year survival rates were 83.8% for LOC, and 78.3% for SC. Long-term survival was significantly lower for SC (67.5% vs. 43.7% at 5 years, log-rank P=.02) During the median follow-up of 25.2 months (range 0.2-109.4), an EL after SC was still present in the 41.4% (12/29) of the cases; sac growth was recorded in 31% (9/29) of SC patients. Conclusion: SC has an early survival benefit but an inferior late survival compared with LOC. The high rates of persistent EL and sac growth after SC impose an EVAR-like lifelong surveillance for this subgroup of patients. Disclosure: Nothing to disclose