Meta-Analysis Compares Open and Endovascular Stent Graft Repair of AAAs

October 23, 2012—In the Journal of the American College of Cardiology: Cardiovascular Interventions, George Dangas, MD, et al published findings of a meta-analysis of randomized trials comparing open versus endovascular stent graft repair of abdominal aortic aneurysms (AAA) (2012;5:1071–1080). The study sought to evaluate short-, intermediate-, and longer-term outcomes, including both AAA-related and all-cause mortality.

The background of the study was that endovascular stent graft placement for AAA has gained broad acceptance as an alternative to open surgical repair due to a lower perioperative morbidity and mortality. The investigators sought to perform a meta-analysis because the intermediate- and long-term all-cause and aneurysm-related mortality vary among studies of open versus endovascular repair for treating AAA.

In the study, investigators queried electronic databases for identification of prospective, randomized trials of open surgery versus endovascular stent graft repair of AAAs. They identified 10 published papers reporting on six studies at different follow-up intervals; these studies involved 2,899 patients with AAA repair procedures, of whom 1,470 underwent endovascular stent graft AAA exclusion and 1,429 were treated by open AAA repair.

As summarized in Journal of the American College of Cardiology: Cardiovascular Interventions, the investigators found that at 30 days, the pooled relative risk of all-cause mortality was lower in the endovascular group (relative risk [RR], 0.35; 95% confidence interval [CI], 0.19–0.64) than in the open surgery group. At intermediate follow-up, the all-cause mortality had a nonsignificant difference (RR, 0.78; 95% CI, 0.57–1.08), the AAA-related mortality was significantly lower (RR, 0.46; 95% CI, 0.28–0.74) and reintervention rates were higher (RR, 1.48; 95% CI, 1.06–2.08) in the endovascular group than in the open surgery group. At long-term follow-up, there was no significant difference in all-cause mortality (RR, 0.99; 95% CI, 0.85–1.15) or AAA-related mortality (RR, 1.58; 95% CI, 0.2–12.74), whereas the significant difference in the rate of reinterventions persisted (RR, 2.54; 95% CI, 1.58–4.08).

The investigators concluded that in patients randomized to open or endovascular AAA repair, all-cause perioperative mortality, as well as AAA-related mortality at short- and intermediate-term follow-up, are lower in patients undergoing endovascular stent graft placement. Greater reintervention was noted in the endovascular group at intermediate follow-up. Long-term survival appeared to converge between the two groups.