Long-term follow-up of type II endoleak embolization reveals the need for close surveillance

Aneurysm growth after endovascular aneurysm repair (EVAR) in patients with type II endoleak is associated with adverse outcomes. This study evaluated the long-term success of embolization of type II endoleaks in preventing aneurysm sac growth.

We retrospectively reviewed outcomes of patients who underwent infrarenal EVAR who were treated for a type II endoleak between 2000 and 2008. Computed tomography scans were evaluated for aneurysm sac growth or shrinkage from the time of treatment of the endoleak. The embolization material used, graft type, target vessel embolized, and comorbidities were evaluated for their association with sac growth or shrinkage.

Ninety-five patients underwent 140 embolization procedures. The mean time from EVAR to embolization was 26.1 ± 22.2 months, and the average increase in size of the aneurysm sac from EVAR to treatment was 0.7 × 0.5 cm. Patients underwent an average of 1.6 ± 0.8 embolization procedures after EVAR. Thirteen patients underwent initial simultaneous embolization of two targets. Embolization was with glue (61%), coils (29%), glue and coils (7%), and Gelfoam (3%; Pfizer Inc, New York, NY). No abdominal aortic aneurysms (AAA) ruptured. Eight patients (8.4%) underwent graft explant and open repair; 19 (20%) required two or more embolization procedures. There was no difference in the target vessel treated or the treatment used in halting sac expansion (>5 mm). Coil embolization alone resulted in more second procedures. The 5-year cumulative survival was 65% (95% confidence interval [CI], 52%-77%), freedom from explant was 89% (95% CI, 81%-97%), freedom from second embolization was 76% (95% CI, 66%-86%), and freedom from sac expansion >5 mm was 44% (95% CI 30%-50%). Univariable analysis identified continued tobacco use (hazard ratio [HR], 2.30; 95% CI, 1.02-5.13; P = .04) was associated with continued sac expansion, and hyperlipidemia (HR, 9.64; 95% CI, 2.22-41.86) was associated with patients requiring a second embolization procedure.

Embolization of type II endoleaks is successful early in preventing aneurysm sac growth and rupture after EVAR. However, a significant number of patients require more than one procedure, and at 5 years, many patients who underwent embolization of a type II endoleak continued to experience sac growth. Patients with hyperlipidemia who undergo coil embolization are more likely to require a second embolization procedure, and patients who smoke have a higher likelihood of AAA sac expansion after embolization. Continued long-term surveillance is necessary in this cohort of patients.