Safety and Validity of the Proposed European Society for Vascular Surgery Infrarenal Endovascular Aneurysm Repair Surveillance Protocol: A Single Centre Evaluation.

Objective: Long term surveillance after endovascular aneurysm repair (EVAR) is essential to detect late complications, but there is variation in practice. The European Society for Vascular Surgery (ESVS) made a recommendation for a new surveillance protocol; one element involves risk stratifying patients depending on sac size reduction and presence of endoleak at their 30 day computed tomography angiogram into low risk groups (delayed imaging to five years) or higher risk groups (continue with the current protocol). The aim was to test this suggested protocol retrospectively within an EVAR patient cohort.

Methods: Data on EVARs performed from October 2009 to October 2019 were collected. Information gathered from an existing surveillance programme was used to assess the proposed ESVS protocol. All patients who underwent re-intervention were reviewed to see whether adopting the proposed ESVS protocol would have detected these events.

Results: In total, 309 procedures were included. Altogether, 219 of these patients had no endoleak (70.9%) and 86 had a type II (27.8%) endoleak. Only four developed a type I or III endoleak. No patient in the low risk cohort (no initial endoleak or sac shrinkage > 1 cm) required secondary intervention. Five year follow up data were available for 103 patients. In the type II endoleak group, there were 28 secondary interventions in 22 patients. No patient experienced a ruptured aneurysm within five years post-operatively. Had the proposed ESVS protocol been followed, all patients requiring a secondary intervention or with increasing sac size would have been detected/captured. Further, adherence to the ESVS guidelines would have resulted in 103 patients with a five year follow up history qualifying for reduced surveillance. A further 120 patients who had reached the three and four year follow up timepoints could have qualified for a reduced surveillance, reducing imaging cost further.

Conclusion: Adopting the proposed ESVS EVAR surveillance protocol safely identified "low risk" patients who did not go on to require a secondary intervention. These patients could benefit from reduced surveillance scanning.