Multicentre comparison between open conversions and semi-conversions for late endoleaks after EVAR

Objective: The aim of this study is to compare early and follow-up outcomes of late open conversions (LOC, with complete or partial endograft explantation) and semi-conversions (SC, with endograft preservation) after endovascular aneurysm repair in a multicenter experience. Methods: All LOC and SC performed from 1997 to 2020 in 11 vascular centers were compared. Endograft infections or thrombosis were excluded. Primary endpoints were early mortality and long-term survival estimates. Secondary endpoints were differences in postoperative complication rates and conversion-related complications during follow-up. Results: In the considered period, 347 patients underwent surgery for endovascular aneurysm repair complications. Among these, 270 were operated on for endoleaks (222 LOC, 48 SC). The two groups were homogeneous in terms of American Society of Anesthesiologists score (LOC, 3.2 ± 0.7; SC, 3 ± 0.5; P = .128) and main endograft characteristics (suprarenal fixation, bifurcated/aorto-uni-iliac configuration). The mean age was 75 ± 8 years for LOC and 79 ± 7 years for SC (P = .009). Reasons for LOC were: 62.2% (138/222) type I endoleak, 21.6% (48/222) type II endoleak, 7.7% (17/222) type III endoleak, and 8.5% (19/222) endotension. Indications for SC were: 64.6% (31/48) type II endoleak, 33.3% (16/48) type I endoleak, and 2.1% (1/48) type III endoleak. Thirty-day mortality was 12.2% (27/222) in the LOC group, and 10.4% (5/48) in the SC group (P = .73). Postoperative complication rate was higher in the LOC group (45.5% vs 29.2%; P = .04). The estimated survival rate after LOC was 80% at 1 year and 64% at 5 years; after SC, it was 72% at 1 year and 37% at 5 years (log-rank P = .01). During the median follow-up of 21.5 months (interquartile range, 2.4-61 months), an endoleak after SC was found in the 38.3% of the cases; sac growth was recorded in the 27.7% of SC patients. Conclusions: SC has an early benefit over LOC in terms of reduced postoperative complications but has a significantly inferior mid-term survival. The high rates of persistent and/or recurrent endoleaks reduce SC durability.