Incidence and Causes of Aneurysm Growth After Endovascular Sealing of Abdominal Aortic Aneurysms

The objective was to analyze the incidence of aneurysm growth after endovascular aneurysm sealing (EVAS) and its relationship with adherence to the instructions for use (IFU) of the Nellix (Endologix, Irvine, Calif) endograft. This was a retrospective observational study that observed the clinical outcomes of patients who had an elective infrarenal EVAS procedure performed at the Royal Liverpool Hospital between December 2013 and January 2018. The primary outcome measure was the occurrence of aneurysm growth after EVAS. Aneurysm growth was defined as a 5% increase in the aortic volume between the renal arteries and the aortic bifurcation from the 1-month scan to any subsequent annual scans. There were 71 patients (55 men) with a mean (standard deviation) age of 76 (6) years who were eligible for inclusion in this study. Aneurysm growth was observed in 8 of 19 (42%) within IFU and 14 of 52 (27%) outside IFU (P = .35). There was no relationship between aneurysm growth and adherence to IFU. Among the patients with aneurysm growth, the median (range) increase in abdominal aortic aneurysm volume was 11% (5%-20%). Abdominal aortic aneurysm growth occurs in a significant proportion of patients at 1 year after EVAS and is not associated with adherence to IFU. Longer follow-up on a larger sample size is essential to understand the long-term clinical outcomes after EVAS.