The Impact of Institutional Volume on Transcatheter Aortic Valve Replacement Outcomes

Prior studies have demonstrated a consistent association between higher institutional procedural volume and improved clinical outcomes. To evaluate the relationship between institutional transcatheter aortic valve replacement (TAVR) volume and key patient outcomes, and to identify which metrics are most sensitive to volume variation. We analyzed 91,494 non-impella-assisted TAVR procedures performed at 118 US hospitals using the Vizient Clinical Data Base (28,077 in 2022; 30,602 in 2023; 32,815 in 2024). Annual case volume categories (e.g., 1-100 through 801-900) were used to stratify institutions. Key outcomes-including mean length of stay (LOS), early mortality, mean ICU stay, and observed mortality-were compared across volume groups using ANOVA and ANCOVA to adjust for case mix index (CMI). Higher institutional TAVR volume was significantly associated with shorter mean LOS in 2022 (ANOVA p = 0.0007; ANCOVA p < 0.0001), 2023 (ANOVA p = 0.0016; ANCOVA p = 0.0003), and 2024 (ANOVA p < 0.0001; ANCOVA p < 0.0001). In 2023, higher volume was associated with significantly lower early mortality (ANOVA p = 0.0195; ANCOVA p = 0.0165). In 2024, higher volume correlated with significantly lower overall observed mortality (ANOVA p = 0.0004; ANCOVA p < 0.0001). No significant associations were found between volume and mean ICU stay in any year. Higher institutional TAVR volume is independently associated with improved outcomes, including reduced LOS, early mortality, and overall observed mortality. These associations persist after adjustment for CMI, suggesting intrinsic differences in care delivery across volume strata.