Coeliac Incorporation Strategy Impacts Visceral Branch Vessel Stability in Fenestrated Endovascular Aneurysm Repair.

Objective: During fenestrated endovascular repair (FEVAR), mesenteric vessels may be incorporated with a scallop or fenestration. The benefits/harms of techniques to incorporate the coeliac axis (CA) have not been assessed for their impact on procedural complexity vs. peri-operative and longer term outcomes; this assessment may instruct a balanced operative strategy for the CA and complex FEVAR, minimising adverse intra- or peri-operative events, and maximising durability.

Methods: This was a retrospective cohort study. Patients undergoing fenestrated or scalloped CA incorporation during FEVAR for a juxtarenal/pararenal/suprarenal aortic aneurysm (January 2015 - December 2019) were reviewed (n = 159) for demographics, intra-procedural/peri-operative outcomes, and re-interventions to five years. Mean follow up for all groups was 3.28 years. The primary outcome of CA instability (occlusion/stenosis/endoleak/re-intervention) was assessed. CA specific re-intervention, re-intervention free survival, and all cause mortality were assessed against incorporation strategy. Secondarily, the harm of CA stenting, comprising intra-operative harms and peri-operative adverse outcomes was interrogated.

Results: The CA was incorporated with a stented fenestration (n = 74), an unstented fenestration (n = 59), and a minority with scallop (n = 26). There were no between group differences in operative indication, or anatomical aneurysm/CA features. Fenestrated stented and unstented patients had longer aortic coverage but the same primary technical success. At follow up, three CA endoleaks occurred in stented fenestrated patients, although scallop patients more often had type 3 endoleaks at the SMA and renal fenestrations (23%). Elevated CA instability in fenestrated unstented patients was driven by CA occlusion (16.9%), but not associated with CA re-intervention, worse re-intervention free survival, or all cause mortality. Regression analysis for visceral branch instability revealed predictors of CA non-stenting and diminished aortic coverage.

Conclusion: In the present authors' experience, the practice of not stenting a CA fenestration does not pose peri-operative or long term clinical harm. At follow up, not stenting the CA is associated with CA instability; however, both fenestration groups are preferable to a shorter (scalloped) endograft as increasing aortic coverage reduces non-CA branch vessel instability.