Surgical Aortic Valve Replacement Outcomes in Non–Transcatheter Aortic Valve Replacement Centers: Implications for Tier-Based Systems of Care

Abstract

BackgroundWith wide expansion of transcatheter aortic valve replacement (TAVR) and dissemination of multidisciplinary-based approaches to care, societies are discussing the implementation of a tier system to valve centers. This study explores the impact of tier-based systems of care on surgical aortic valve replacement (SAVR) outcomes at institutions that perform SAVR only. MethodsMedicare beneficiaries undergoing SAVR procedures from 2012 to 2015 were included. The SAVR hospitals were stratified into either tier A, valve centers with a TAVR program; or tier B, valve centers without a TAVR program. Adjusted survival, assessed by multivariable Cox regression, controlled for program type and patient risk profile. Time-dependent analysis accounted for hospitals that initiated a TAVR program during the study period. ResultsOverall, there were 562 tier A and 485 tier B SAVR hospitals. Tier A hospitals had significantly higher comorbidity burden compared with tier B hospitals (all P < .05) but had significantly lower rates of 30-day mortality (3.2% vs 4.1%) and 1-year mortality (8.1% vs 9.4%; both P < .05). After risk stratification, tier B hospitals had significantly worse 30-day mortality compared with tier A hospitals for all patient risk-profiles, except for the low-risk patients (P < .01). These findings persisted in the time-dependent analysis. Adjusted midterm survival was higher in tier A vs tier B hospitals. ConclusionsLow-risk patients can safely undergo SAVR in both tier level hospitals without compromising outcomes. Establishment of quality of care measures, especially in the SAVR-only hospitals, remains paramount and should be closely integrated when designing tier-based systems for aortic valve replacement care.