Association between Hospital Surgical Aortic Valve Replacement Volume and Transcatheter Aortic Valve Replacement Outcomes

Abstract

Importance: The Centers for Medicare & Medicaid Services national coverage determination for transcatheter aortic valve replacement (TAVR) includes volume requirements for surgical aortic valve replacement (SAVR) for hospitals seeking to initiate or continue TAVR programs. Evidence regarding the association between SAVR volume and TAVR outcomes is limited. Objective: To examine the association of hospital SAVR and combined SAVR and TAVR volumes with patient outcomes of TAVR procedures performed within 1 year, 2 years, and for the entire period after initiation of TAVR programs. Design, Setting, and Participants: This observational cohort study included 60538 TAVR procedures performed in 438 hospitals between October 1, 2011, and December 31, 2015, among Medicare beneficiaries. Main Outcomes and Measures: The associations between SAVR volume, SAVR and TAVR volumes, and risks of death, death or stroke, and readmissions within 30 days were determined using a hierarchical logistic regression model adjusting for patient and hospital characteristics. The association between SAVR and SAVR and TAVR volumes and 1-year and 2-year mortality after TAVR procedures was determined using a multivariable proportional hazard model with a robust variance estimator. The associations for procedures performed within 1 year, 2 years, and for the entire period after initiation of TAVR programs were examined. Results: Among the 60538 patients, 29173 were women and 31365 were men, with a mean (SD) age of 82.3 (8.0) years. Hospitals with high SAVR volume (mean annual volume, ≥97 per year) were more likely to adopt TAVR early and had a higher growth in TAVR volumes over time (median TAVR volume by hospitals with high SAVR volume and low SAVR volume: year 1, 32 vs 19; year 2, 48 vs 28; year 3, 82 vs 38; year 4, 118 vs 54; P