Stability of the aneurysmatic sac post-EVAR could no longer be a reliable criterion of healing

BACKGROUND: Evaluation of the impact of aneurysm sac behavior in terms of either stability or shrinkage after endovascular aneurysm repair (EVAR) on long-term clinical outcomes. METHODS: A retrospective study was conducted on 1483 consecutive patients who underwent EVAR from 1999 to 2021 at our institution. 1037 patients met inclusion criteria (1037/1483, 69.9%): abdominal aortic or aorto-iliac aneurysm, elective surgery, follow-up (FU) 212 months. Patients who had sac stability (330/1037, 31.8%) and patients who demonstrated sac shrinkage (542/1037, 52.2%) at FU were compared; patients who presented sac increase at FU were excluded (165/1037, 16%). Primary endpoints: rupture rates, need for surgical conversion, and long-term aneurysm-related mortality. Secondary endpoints: all type endoleak rates and long-term reintervention rates. RESULTS: Mean FU was 61.2 months (IQ 26-85.7 months). In terms of comorbidities, the group of patients with stable sac showed greater association with polidistrectual atherosclerotic manifestations. Estimated 12-year survival was 42.9% in the stable sac group and 65% in the shrinked group (P<0.001), although there were no significant differences in terms of freedom from aneurysm-related death (97.3% vs. 95.4% estimated at 12 years, P=0.493). Patients with sac stability had higher rates of rupture (2.1% vs. 0.6%, P=0.035) and surgical conversion (2.1% vs. 0.6%, P=0.035). The stable sac group had significantly higher rates of all type endoleak during FU (45.8% vs. 24%, P<0.001). Estimated 12-year freedom from reintervention rates were 56.2% and 83.9% respectively (P<0.001). CONCLUSIONS: After more than 20 years of EVAR experience it is probably time to reconsider the procedure clinical success parameters as a patient with a stable sac cannot be considered healed.