Secondary intervention and surveillance after abdominal aortic aneurysm repair: retrospective cohort study

Abstract

Introduction: The early survival benefits of endovascular aortic aneurysm repair (EVAR) seem to decrease over time and late aneurysm-related mortality might be even higher than open repair. The objectives of this study are to determine the rate of secondary intervention (SI) and compliance with surveillance following EVAR. Methods: This is a retrospective cohort study of consecutive patients submitted to elective EVAR, between February/2009 and May/2019 in a single institution. Symptomatic or ruptured AAA, mycotic aneurysms, isolated iliac aneurysms and complex abdominal aortic repairs were excluded. The primary outcomes were freedom from SI and compliance with follow-up, defined as surveillance imaging performed within a periodicity no longer than 18 months. Results: A total of 214 patients underwent EVAR, 97% were male with 72±10 years old. After a median follow up of 44 months (95% Confidence Interval [95%CI] 39-49), there were 42 SIs performed in 25 patients. Freedom from SI was 96.3±1.3% at 30 days and 93.6±1.7%, 90.3±2.2% and 85.9±3.0 at 1, 3 and 5 years. Endoleaks were the main cause of SI after EVAR, namely type 1 and type 2. From all SIs, 33.3% (14/42) were due to symptomatic complications. At 5 years, aneurysm sac regression was lower in the SI group (85.1±9.7% vs 55.6±5.3%, P=0.017), but patient survival was identical (84.4±7.2 vs 76.7±4.1, P=0.386). The first surveillance imaging was performed during the first 30 days in 69 patients (36.3%). Compliance with surveillance was 80.4±2.9% at 1 year, and 37.7±5.4% at 5 years. Conclusions: SIs are associated with a lower aneurysm sac regression and are essential for EVAR to achieve its full potential. Most SIs are due to image-detected asymptomatic complications, however, compliance with surveillance decrease with longer follow-up times. The importance of this finding in long-term outcomes of EVAR deserves further investigation.