Hospital and Surgeon Annual Volume Thresholds Associated With Improved 30-Day Mortality After Fenestrated and Branched Aortic Repair.

Abstract

This study aims to assess the impact of surgeon and hospital volume on mortality following fenestrated and branched repair of aortic aneurysms (F/BEVAR) and identify minimum volume thresholds for repair. While hospital volume predicts outcomes after standard open and endovascular aortic repair, the volume-outcome relationship for F/BEVAR remains poorly defined. We performed a retrospective cohort study using 100% Medicare fee-for-service claims (2016-2023) to identify adults undergoing F/BEVAR. We used locally estimated scatterplot smoothing (LOESS) and derivative-based methods to identify hospital- and surgeon-level annual volume thresholds associated with 30-day mortality. Multivariable logistic regression were used to assess the association between hospital and surgeon volume (separately) and 30-day mortality. There were 8015 patients who received F/BEVAR (mean age 76.1±6.8 y, 27.7% female, 90.9% White race). Median annual hospital and surgeon volume was 2 cases (range 1-70) and 1 case (range 1-51), respectively. Overall, 350 (4.4%) of patients experienced mortality within 30 days. The LOESS plots identified inflection points at 9 cases/year for hospitals and 7 cases/year for surgeons. After adjusting for patient risk factors, there was a significant association of both low-hospital volume (≤9 cases/year) (aOR 1.43, 95% CI 1.02, 1.99) and surgeon volume (≤7 cases/year) (aOR 1.51, 95% CI 1.04, 2.18) with 30-day mortality after F/BEVAR. There is a significant volume-outcome relationship after F/BEVAR. As commercially available devices become available, volume thresholds may provide an opportunity to guide dissemination of the technology while ensuring acceptable patient outcomes.