Center-level Outcomes Following Elective Fenestrated Endovascular Aortic Aneurysm Repair in the Vascular Quality Initiative Database

Background Hospital volume is associated with mortality after open aortic aneurysm repair. Fenestrated and branched endovascular aortic repair (B-FEVAR) has been increasingly used for repair of complex thoracoabdominal and juxtarenal aneurysms but evidence of a center-volume relationship is limited. We aimed to measure the association of center volume with in-hospital mortality, post-operative outcomes and 1-year survival following B-FEVAR. Methods Patients undergoing elective endovascular thoracoabdominal and complex abdominal aneurysm repair with branch intervention (2014-2021) listed within the national Vascular Quality Initiative Thoracic Endovascular Aortic Repair (TEVAR)/complex EVAR database were analyzed. Centers were grouped into quartiles by mean annual procedure volume. Multivariable regression was used to evaluate the effect of center volume on in-hospital mortality adjusting for baseline and procedural characteristics. Kaplan-Meier estimation, log rank test and mixed effects Cox regression were used to evaluate 1-year survival. Results A total of 4,302 adult elective F-BEVAR procedures were identified at a total of 163 centers. In-hospital mortality did not differ by hospital volume (Q1=35/1059 (3.3%), Q2=30/1063 (2.8%), Q3=33/1120 (2.9%), and Q4=44/1060 (4.2%), p = 0.308). The high volume group had a higher rate of major complication (Q1=14.9%, Q2=12.8%, Q3=13.3%, and Q4=20.1%, adjusted p < 0.001). Physician modified grafts were more frequently employed in high-volume centers (Q1=4.5%, Q2=18.7%, Q3=11.3%, and Q4=19.2%, p < 0.001) with a decreased incidence of any endoleak noted at the end of the procedure (Q1=34.9%, Q2=32.8%, Q3=30.0%, and Q4=29.0%, p = 0.003). In the multivariable analysis, in-hospital mortality was not associated with center volume comparing very low volume to medium and high volume centers (OR [95% CI] vs Q4: Q1 =1.1 [0.6-1.9], Q2 =0.6 [0.4-1.1], and Q3 =0.9 [0.5–1.5], p all >0.05). No significant difference was found in 1-year survival between center-volume groups. Conclusions In-hospital mortality is not associated with procedure volume within centers performing complex endovascular aortic repair. However, complication rates and endoleak may be associated with procedure volume. Long-term outcomes by annualized procedure volume, specifically graft durability and sac expansion, should be investigated.