Early Sac Behavior Can Help Predict Endoleak Resolution or Persistence in Patients With Early Type II Endoleak

Endoleak is a known complication of endovascular aortic repair (EVAR). The purpose of this study was to investigate the natural behavior of endoleaks based on initial aneurysm sac behavior. We analyzed 1631 patients who underwent EVAR for abdominal aortic aneurysm at a single center between 2001 and 2020. Patients were stratified into “No Leak” or “Leak” groups and then further grouped by sac behavior: “expansion,” “stabilization,” or “regression.” Endoleaks were confirmed on computed tomography, magnetic resonance imaging, or angiography. Statistical analysis was performed using χ2 tests and odds ratios. Among 1631 patients who underwent EVAR, 296 (18.2%) had type II endoleak at first follow-up. Of these 296, 125 (42.2%) had sac regression, 121 (40.9%) had sac expansion, and 50 (16.9%) had stable sacs. At a mean follow-up of 52.9 months (standard deviation [SD] ± 46.9 months), the regression group demonstrated 50 (54.9%) endoleak resolution, whereas 27 (29.6%) showed persistent type II, 2 (2.2%) developed late type I, and 12 (13.2%) had an unspecified leak. The expansion group at a mean follow-up of 58.7 months (SD ±42.3 months) had 24 (19.8%) with endoleak resolution, 64 (52.9%) with persistent type II endoleak, 10 (8.3%) develop late type I endoleak, and 23 (19.0%) had unspecified endoleaks. The stable group at a mean follow-up of 27.9 months (SD ±34.0 months) showed 12 (24%) with leak resolution, 32 (64%) with persistent type II leak, 2 (4%) late type I, and 4 (8%) with a late unspecified leak. Regression was associated with fewer developments of late endoleak than the nonregression group (45% vs 76%; P < .001). Nonregression was 8.33-fold more likely to develop late type I endoleak, 4.94 fold more likely to have persistent type II endoleak, and 3.13-fold more likely to develop late unspecified endoleak compared with regression (Table). Regression was 4.59-fold more likely to experience spontaneous endoleak resolution compared with nonregression (Table). EVAR patients with early type II endoleak and sac regression were less likely to develop late type I or unspecified endoleaks and were more likely to undergo spontaneous endoleak resolution. This study confirms that sac regression is the most important prognostic metric for successful EVAR even in patients with early type II endoleak.TableOdds ratio analysis of the presence of late type I-III endoleak across sac behavior groupsNo leak, regressionNo leak, stabilizationNo leak, expansionOdds ratio (95% CI)P valueType I late endoleak21028.33 (1.76-39.54).008Type II late endoleak2764324.94 (2.70-9.04)<.0001Unspecified late endoleak122343.13 (1.40-6.98).006Resolution of endoleak5024120.22 (0.13-0.38)<.0001CI, Confidence interval.Boldface P values represent significance P < .05. Open table in a new tab