Decreased Size of Abdominal Aortic Aneurysm Repair in the Endovascular Era: Have Perceptions of Clinical Indications Changed?

Objectives: Following the UK Small Aneurysm and ADAM trials, class 1 evidence for size criteria for AAA repair has shifted towards larger aneurysm observation. We sought to determine if the introduction of an endovascular program alters physician perceptions regarding operative AAA indications.
Methods: A single institution, retrospective review (2/99-2/05) of consecutive AAA repairs was performed representing 16 surgeons in 6 groups. Size and operative indication was determined at six separate intervals (one year prior to the introduction of an EVAR program and each of the following five years thereafter).
Results: 378 patients underwent infrarenal AAA repair. AAA size decreased significantly following EVAR introduction in the first two years reaching a subsequent smaller size operative threshold thereafter(5.8cm, SD1.36cm[pre-EVAR], 5.5cm, SD1.30cm[EVAR year 1], 5.0cm,SD1.01cm[EVAR year 2], 5.1cm,SD1.33cm[EVAR year 3], 5.1cm,SD1.59cm[EVAR year 4], and 5.1cm, SD1.02cm[EVAR year 5]p<0.05. An increasing percentage of AAA <5.0cm were offered operative repair following EVAR (27% pre-EVAR increasing to 33%, 46%, 46%, 52%, and 45% with each post-EVAR year interval)p<0.05. There was a trend towards operative repair of very small (<4.0cm) AAAs with increasing EVAR experience (6% pre-EVAR increasing to 7%, 10%, 12%, 11%and 11% with each post-EVAR year) and was justified by non-size criteria: rapid size increase, pain, tenderness, morphology, thrombo-embolic disease, associated iliac aneurysm, or patient anxiety.
Conclusion: Perception of AAA operative indications changed following the introduction of EVAR with smaller aneurysms being repaired based increasingly on non-size related criteria. The changes were most pronounced immediately following introduction of EVAR and then stabilized in subsequent years.