UC San Diego

Background

Type II endoleaks (ELII) are the most common complication following endovascular aneurysm repair (EVAR). Persistent ELII require continual surveillance and have been shown to increase the risk of Type I and III endoleaks, sac growth, need for intervention, conversion to open or even rupture, directly or indirectly. These are often difficult to treat following EVAR, and there are limited data regarding the effectiveness of prophylactic treatment of ELII. The aim of this study is to report the midterm outcomes of prophylactic perigraft arterial sac embolization (pPASE) performed in patients undergoing EVAR.

Methods

This is a comparison of 2 elective cohorts of those undergoing EVAR using the Ovation stent graft with and without prophylactic branch vessel and sac embolization. Patients who underwent pPASE at our institution had their data collected in a prospective, institutional review board-approved database. These were compared against the core lab-adjudicated data from the Ovation Investigational Device Exemption trial. Prophylactic PASE was performed at the time of EVAR with thrombin, contrast, and Gelfoam if the lumbar or mesenteric arteries were patent. Endpoints included freedom from ELII, reintervention, sac growth, all-cause mortality, and aneurysm-related mortality.

Results

Thirty-six patients (13.1%) underwent pPASE, while 238 patients (86.9%) had standard EVAR. Median follow-up was 56 months (33-60 months). The 4-year freedom from ELII estimates were 84% for the pPASE versus 50.7% for the standard EVAR group (P = 0.0002). All aneurysms in the pPASE group remained stable in size or demonstrated regression, whereas aneurysm sac expansion was seen in 10.9% of the standard EVAR group, P = 0.03. At 4 years, mean AAA diameter decreased by 11 mm (95% CI 8-15) in the pPASE group versus 5 mm (95% CI 4-6) for the standard EVAR group, P = 0.0005. There were no differences in the 4-year freedom from all-cause mortality and aneurysm-related mortality. However, the difference in reintervention for ELII trended toward significance (0.0% vs. 10.7%, P = 0.1). On multivariable analysis, pPASE was associated with a 76% reduction in ELII [(95% CI): 0.24 (0.08-0.65), P = 0.005].

Conclusions

These results suggest that pPASE in those undergoing EVAR is safe and effective in the prevention of ELII and significantly improves sac regression over standard EVAR while minimizing the need for reintervention.