A Canadian multicenter experience describing outcomes following EVAR graft explant.

ABSTRACT Introduction Most of the studies describing outcomes following EVAR explant have been from single, high-volume, centers. We carried out a multicenter cross-Canadian study of outcomes following EVAR graft explants. Our objectives were to describe outcomes following late open conversion and explant of EVARs from various Canadian centers and describe the techniques and outcomes depending on the indication for explant. Methods The Canadian Vascular Surgery Research Group carried out a retrospective multicenter study of all cases of EVAR graft explant occurring at participating centers between 2003-2018. Data was collected using a standardized, secure, online platform (Redcap). Univariate statistics were used to compare techniques and outcomes based on the indication for graft explant. Results Patient data from 111 EVAR explants collected from 13 participating centers was analyzed. Mean age at the time of explant was 74 years and average aneurysm size was 7.5cm; with 28% having at least one IFU violation at the time of EVAR. Average time between EVAR and explant was 42.5 months. The most common indications for explant was endoleak in 66 patients (type Ia=46; type Ib=2; type II=9; type III=2; endotension=7); infection in 20 patients; rupture in 18 patients (type Ia=10; type Ib=1; type II=1; type III=2; endotension=1) and graft thrombosis in 7 cases. Overall 30-day mortality was 11% and 45% of patients suffered at least one major perioperative complication. Mortality was significantly higher for ruptured patients (33.3%) and those done for infection (15%) when compared with elective, endoleak, patients (4.5%, p=.003). Average center volume over the last 15 years was 8 cases with a wide range (19 to 2 cases). There was a trend towards a higher mortality among patients done in centers with fewer than 8 cases compared to those with 8 or more cases (19% vs 9%) but this did not reach statistical significance (p=0.23). Overall, 41% of patients had at least one attempt at endosalvage prior to explant, with the highest proportion among patients who underwent EVAR explant for endoleak (51%); while only 22% of patients who ruptured had an attempt at endosalvage prior to explant. Conclusions EVAR graft explants have an increasing incidence in Canada. Patients done electively for endoleak have a lower mortality than those done for either infection or rupture, and thus patients who have an indication should be offered surgery before symptoms or rupture occurs. There is a trend towards higher mortality when done in centers with lower volumes.