Occult type I or III endoleaks are a common cause of failure of type II endoleak treatment after endovascular aortic repair.

OBJECTIVE

Most type II endoleaks have a benign natural history, but 6% to 8% are associated with sac enlargement and respond poorly to treatment. Our aim was to evaluate whether these enlargements are associated with delayed or occult type I and III endoleaks.

METHODS

Patients with interventions for endoleak after endovascular aortic repair from 2000 to 2016 were reviewed retrospectively. Patient demographics, comorbidities, endoleak type, secondary procedures, aortic sac growth (≥5 mm), and mortality were collected. Successful treatment was defined as endoleak resolution with no further aortic sac growth. Secondary procedures, ruptures, endograft explant, and death were captured.

RESULTS

There were 130 patients diagnosed with a primary type II endoleak after endovascular aortic repair at a median of 1.3 months (interquartile range, 1.0-13.3 months). One hundred eighteen had their initial treatment for a primary type II. Twelve of the 130 were initially stable and observed, but were treated for a delayed type I or III endoleak. The 130 patients underwent 279 procedures for endoleaks (mean of 2.2 ± 1.3) over 6.9 ± 3.8 years of follow-up. Of the 118 patients treated for primary type II endoleaks, 26 (22.0%) later required interventions for delayed type I and III endoleaks. The mean time to intervention for a delayed type I or III endoleak was 5.4 ± 2.8 years. Overall, there were 16 type IA, 11 type IB, 2 type III, 7 combined type IA/IB, and 2 type IA/III delayed endoleaks. The odds of harboring a delayed type I or III endoleak was 22.0% before the first attempt at type II endoleak treatment, 35.1% before the second, 44.8% before the third, and 66.6% before the fourth attempts. Rapid aortic sac growth of ≥5 mm/y before initial endoleak treatment was associated with increased risk for delayed type I or III endoleak (47.8 vs 14.1%; P = .003). Patients with delayed type I or III endoleaks had a lower successful treatment rate (8.3% vs 52.3%; P = .001) than those with only type II endoleaks. Late rupture was increased with delayed type I or III endoleak (P = .002), whereas mortality (P = .96) and aortic-related mortality (P = .46) were similar. Graft explant (P = .06) trended toward an increase with a delayed type I or III endoleak, but was not statistically significant.

CONCLUSIONS

Failed attempts treating type II endoleaks and/or a rapid aortic sac growth of 5 mm/y or greater should raise the suspicion of a delayed or occult type I or III endoleak. Occult endoleaks are associated with decreased chance of endoleak resolution.