Challenging Anatomy Predicts Mortality and Complications After Endovascular Treatment of Ruptured Abdominal Aortic Aneurysm

Abstract

Purpose: To analyze the effects of aortic anatomy and endovascular aneurysm repair (EVAR) inside and outside the instructions for use (IFU) on outcomes in patients treated for ruptured abdominal aortic aneurysms (rAAA).

Methods: All 112 patients (mean age 73 years; 102 men) treated with standard EVAR for rAAA between 2000 and 2012 in 3 European centers were included in the retrospective analysis. Patients were grouped based on aortic anatomy and whether EVAR was performed inside or outside the IFU. Data on complications, secondary interventions, and mortality were extracted from the patient records. Cox regression analysis was performed to assess predictors of mortality and complications; results are presented as the hazard ratio (HR) with 95% confidence interval (CI). Survival was analyzed using the Kaplan-Meier method.

Results: Of the 112 patients examined, 61 (54%) were treated inside the IFU, 43 (38%) outside the IFU, and 8 patients lacked adequate preoperative computed tomography scans for determination. Median follow-up of those surviving 30 days was 2.5 years. Mortality at 30 days was 15% (95% CI 6% to 24%) inside the IFU vs 30% (95% CI 16% to 45%) outside (p=0.087). Three-year mortality estimates were 33.8% (95% CI 20.0% to 47.5%) inside the IFU vs 56% (95% CI 39.7% to 72.2%) outside (p=0.016). At 5 years, mortality was 48% (95% CI 30% to 66%) inside the IFU vs 74% (95% CI 54% to 93%) outside (p=0.015). Graft-related complications occurred in 6% (95% CI 0% to 13%) inside the IFU and 30% (95% CI 14% to 42%) outside (p=0.015). The rate of graft-related secondary interventions was 14% (95% CI 4% to 22%) inside the IFU vs 35% (95% CI 14% to 42%) outside (p=0.072). In the multivariate analysis, neck length <15 mm (HR 8.1, 95% CI 3.0 to 21.9, p<0.001) and angulation >60° (HR 3.1, 95% CI 1.0 to 9.3, p=0.045) were independent predictors of late graft-related complications. Aneurysm neck diameter >29 mm (HR 2.5, 95% CI 1.1 to 5.9, p=0.035) was an independent predictor of overall mortality.

Conclusion: Long-term mortality and complications after rEVAR are associated with aneurysm anatomy. The role of adjunct endovascular techniques and the outcome of open repair in cases with challenging anatomy warrant further study.

Keywords: abdominal aortic aneurysm; complications; endovascular aneurysm repair; instructions for use; mortality; neck angulation; neck diameter; neck length; secondary interventions; stent-graft.