ABSTRACT: IMPORTANCE:There is a need to describe contemporary outcomes of surgical aortic valve replacement (AVR) as the population ages and transcatheter options emerge. OBJECTIVE:To assess procedure rates and outcomes of surgical AVR over time. DESIGN, SETTING, AND PARTICIPANTS:A serial cross-sectional cohort study of 82,755,924 Medicare fee-for-service beneficiaries undergoing AVR in the United States between 1999 and 2011. MAIN OUTCOMES AND MEASURES:Procedure rates for surgical AVR alone and with coronary artery bypass graft (CABG) surgery, 30-day and 1-year mortality, and 30-day readmission rates. RESULTS:The AVR procedure rate increased by 19 (95% CI, 19-20) procedures per 100,000 person-years over the 12-year period (P<.001), with an age-, sex-, and race-adjusted rate increase of 1.6% (95% CI, 1.0%-1.8%) per year. Mortality decreased at 30 days (absolute decrease, 3.4%; 95% CI, 3.0%-3.8%; adjusted annual decrease, 4.1%; 95% CI, 3.7%- 4.4%) per year and at 1 year (absolute decrease, 2.6%; 95% CI, 2.1%-3.2%; adjusted annual decrease, 2.5%; 95% CI, 2.3%-2.8%). Thirty-day all-cause readmission also decreased by 1.1% (95% CI, 0.9%-1.3%) per year. Aortic valve replacement with CABG surgery decreased, women and black patients had lower procedure and higher mortality rates, and mechanical prosethetic implants decreased, but 23.9% of patients 85 years and older continued to receive a mechanical prosthesis in 2011. CONCLUSIONS AND RELEVANCE:Between 1999 and 2011, the rate of surgical AVR for elderly patients in the United States increased and outcomes improved substantially. Medicare data preclude the identification of the causes of the findings and the trends in procedure rates and outcomes cannot be causally linked. Nevertheless, the findings may be a useful benchmark for outcomes with surgical AVR for older patients eligible for surgery considering newer transcatheter treatments.