Clinical and economic outcomes after surgical aortic valve replacement in Medicare patients

BACKGROUND Aortic valve replacement (AVR) is the standard of care for patients with severe, symptomatic aortic stenosis who are suitable surgical candidates, benefiting both non-high-risk and high-risk patients. The purpose of this study was to report long-term medical resource use and costs for patients following AVR and validate our assumption that high-risk patients have worse outcomes and are more costly than non-high-risk patients in this population. METHODS Patients with aortic stenosis who underwent AVR were identified in the 2003 Medicare 5% Standard Analytic Files and tracked over 5 years to measure clinical outcomes, medical resource use, and costs. An approximation to the logistic EuroSCORE (European System for Cardiac Operative Risk Evaluation) based on administrative data was used to assess surgical risk, with a computed logistic EuroSCORE > 20% considered high-risk. RESULTS We identified 1474 patients with aortic stenosis who underwent AVR, of whom 1222 (82.9%) were non-high-risk and 252 (17.1%) were high-risk. Among those who were non-high-risk, the mean age was 73.3 years, 464 (38.2%) were women, and the mean logistic EuroSCORE was 7%, whereas in those who were high-risk, the mean age was 77.6 years, 134 (52.8%) were women, and the mean logistic EuroSCORE was 37%. All-cause mortality was 33.2% for non-high-risk and 66.7% for high-risk patients at 5 years. Over this time period, non-high-risk patients experienced an average of 3.9 inpatient hospitalizations and total costs of $106,277 per patient versus 4.7 hospitalizations and total costs of $144,183 for high-risk patients. CONCLUSION Among elderly patients undergoing AVR, long-term mortality and costs are substantially greater for high-risk than for non-high-risk individuals. These findings indicate that further research is needed to understand whether newer approaches to aortic valve replacement such as transcatheter AVR may be a lower cost, clinically valuable alternative.