Predicting Features of Visceral Stent Failure in Fenestrated Endovascular Aortic Aneurysm Repair

Abstract

Purpose: Visceral stents in fenestrated endovascular aortic repair (FEVAR) have a significant risk of complications and carry a considerable burden of reinterventions. The aim of this study is to identify preoperative and intraoperative predictors of visceral stent failure. Materials: A retrospective review of 75 consecutive FEVARs in a single center from 2013 to 2021 was undertaken. Data on mortality, stent failure, and reintervention pertaining to 226 visceral stents were collected. Methods: Anatomical features including aortic neck angulation, aneurysm diameter, and angulation of target viscerals were obtained from preoperative computed tomography (CT) scans. Stent oversizing and intraprocedural complications were recorded. Postoperative CT scans were analyzed to determine the length of cover of target vessels. Results: Only bridging stents through fenestrations to visceral vessels were considered; 28 (37%) cases had 4 visceral stents, 24 (32%) had 3, 19 (25%) had 2, 4 (5%) had 1. Thirty day mortality was 8%, a third of which was related to visceral stent complications. Intraprocedural complexity was documented during the cannulation of 8 (3.5%) target vessels, with a technical success rate of 98.7%. A significant endoleak or visceral stent failure was identified in 22 stents (9.8%) postoperatively, of which 7 (3%) had in-patient reintervention within 30 days. Further reinterventions at 1, 2, and 3 years were 12 (5.4%), 2 (1%), and 1 (0.4%), respectively. Most reinterventions were for renal stents (n=19, 86%). A smaller stent diameter and a shorter length of visceral stent were significant predictors of failure. No other anatomical feature or stent choice was found to be a significant predictor of failure. Conclusions: The modality of visceral stent failures varies, but renal stents with a smaller diameter and/or shorter length are more likely to fail over time. Their complications and reinterventions are common and carry a significant burden; therefore, close surveillance must be continued long term. Clinical impact With this work we share the methodology adopted at our centre to treat juxtarenal aneurysm with FEVAR. Thanks to this detailed review of anatomical and technical features we provide guidance for endovascular surgeons to face hostile aneurysm with peculiar visceral vessels anatomy. With our findings will also motivate industries in their attempt to produce improved technologies able to overcome issues identified in this paper.