To regress or not to regress? Outcomes of aneurysm sac behavior after endovascular aortic aneurysm repair: A systematic review and meta-analysis.

Abstract

To evaluate the impact of aneurysmal sac regression vs failure to regress on perioperative and long-term outcomes after endovascular aortic aneurysm repair (EVAR). Article screening was conducted using Medline, Embase, and the Cochrane databases. The primary outcome was overall survival; secondary outcomes included reintervention-free survival, endoleak during follow-up, aneurysmal rupture, and reintervention during follow-up. End points were compared using risk ratios (RRs) for binary outcomes and hazard ratios (HRs) for long-term outcomes. For all outcomes, 95% confidence intervals (CIs) were calculated. Subgroup analysis was done for studies including fenestrated/branched EVAR (F/BEVAR) patients and for studies comparing sac regression to sac stability. A trial sequential analysis was done for the short-term outcomes. Heterogeneity was assessed through the I² statistic. GRADE assessment of the findings was performed. Twenty-seven studies comprising 36,822 patients were included. Sac regression was associated with improved overall survival in the overall analysis (HR, 0.70; 95% CI, 0.61-0.80; P < .00001). In the F/BEVAR subgroup, sac regression was associated with a numerically lower hazard of death; however, this association did not reach statistical significance (HR, 0.87; 95% CI, 0.49-1.53; P = .62). This association persisted for endoleak during follow-up, with lower risk observed in the overall analysis (RR, 0.55; 95% CI, 0.41-0.72; P < .0001) and in the F/BEVAR subgroup (RR, 0.55; 95% CI, 0.41-0.75; P = .0001). Patients with sac regression also demonstrated better reintervention-free survival (HR, 0.37; 95% CI, 0.27-0.53; P < .00,001) and a lower incidence of reintervention during follow-up and aneurysm rupture; however, these latter outcomes were not statistically significant within the F/BEVAR subgroup. Statistical significance persisted across all outcomes in the subgroup analysis comparing sac regression with stable sac. Sac regression after EVAR confers superior outcomes compared with failure to regress. Our findings underscore the importance of sac behavior as a key indicator in post-EVAR surveillance and long-term risk stratification.