March 18, 2020
Meta-Analysis and Meta-Regression Analysis Findings Favor EVAR Versus Open Repair for Ruptured AAA
March 18, 2020—Nikolaos Kontopodis, MD, et al published findings from a meta-analysis and meta-regression analysis of endovascular aneurysm repair (EVAR) and open repair outcomes for ruptured abdominal aortic aneurysm (AAA) in the European Journal of Vascular and Endovascular Surgery (EJVES; 2020;59:399–410).
The quantitative synthesis included 136 studies reporting a total of 267,259 patients (58,273 EVAR patients and 208,986 open surgery patients). The aim was to assess perioperative mortality of EVAR versus open repair for ruptured AAA and to investigate whether outcomes have improved over the years and if there is an association between institutional caseload and perioperative mortality.
As summarized in EJVES, the investigators searched electronic information sources (MEDLINE, EMBASE, CINAHL, CENTRAL) up to August 2019. A systematic review was carried out according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using a registered protocol (CRD42018106084). Studies were selected that reported perioperative mortality of EVAR for ruptured AAA.
Using random-effects models, a proportion meta-analysis was conducted and summary estimates of odds ratios (ORs) and 95% confidence intervals (CIs) for EVAR versus open surgical repair were obtained. Mixed-effects regression models were developed to investigate outcome changes over time and with institutional caseload.
In EJVES, the investigators reported that the pooled perioperative mortality of EVAR and open surgical repair was 0.245 (95% CI, 0.234–0.257) and 0.378 (95% CI, 0.364–0.392), respectively. EVAR was associated with reduced perioperative mortality (OR, 0.54; 95% CI, 0.51–0.57; P < .001).
Meta-regression analysis found:
- Decreasing perioperative mortality in the years after EVAR (P < .001) and open repair (P < .001)
- Decreasing OR of perioperative mortality in favor of EVAR (P = .053)
- Significant positive association between perioperative mortality and institutional caseload for open repair (P = .004)
The investigators concluded that if EVAR can be performed, it is a better treatment for ruptured AAA in light of the reduced perioperative mortality compared with open surgery. They noted that outcomes of both EVAR and open surgical repair have improved over the years, and the difference in perioperative mortality in favor of EVAR has become more pronounced. There is a significant association between perioperative mortality and institutional caseload for open repair of ruptured AAA, stated the investigators in EJVES.