Maximal aortic diameter affects outcome after endovascular repair of abdominal aortic aneurysms

The purpose of this study was to evaluate whether maximal aortic diameter affects outcome after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm (AAA).

Clinical data of patients undergoing EVAR between 1997 and 2011 for nonruptured asymptomatic AAAs in a tertiary center were reviewed. Patients were classified according to diameter of AAA: group 1, <5.0 cm; group 2, 5.0 to 5.4 cm; group 3, 5.5 to 5.9 cm; and group 4, ≥6.0 cm. The primary end point was all-cause mortality; secondary end points were complications, reinterventions, and ruptures.

There were 874 patients studied (female, 108 [12%]; group 1, 119; group 2, 246; group 3, 243; group 4, 266); mean age was 76 ± 7.2 years. The 30-day mortality rate was 1.0%, not significantly different between groups (P = .22); complication and reintervention rates were 13% and 4.1%, respectively, similar between groups (P < .05). Five-year survival was 68%; freedom from complications and reinterventions was 65% and 74%, respectively; rupture rate was 0.5%. Multivariate analysis revealed that factors associated with all-cause mortality included maximal aortic diameter, age, gender, surgical risk, cancer history, and endograft type (P < .05). Group 4 had increased risks of mortality (hazard ratio [HR], 2.0; 95% confidence interval [CI], 1.38-2.85; P = .002) and complications (HR, 1.6; 95% CI, 1.2-2.7; P = .009) relative to group 1. Reinterventions were more frequent for aneurysms ≥6.0 cm (HR, 2.0; 95% CI, 1.2-3.3; P = .01). Late rupture rate after EVAR was not different between groups.

Maximal aortic diameter is associated with long-term outcomes after elective EVAR. Patients with large AAAs (≥6.0 cm) have higher all-cause mortality, complication, and reintervention rates after EVAR than those with smaller aneurysms. We continue to recommend that AAAs be repaired when they reach 5.5 cm as recommended by the guidelines of the Society for Vascular Surgery. On the basis of our data, EVAR should be considered even in high-risk patients with a maximal aortic diameter between 5.5 and 6.0 cm because surgical risk with aneurysm size above 6.0 cm will increase significantly.