Utilization of mechanical prostheses and outcomes of surgical aortic valve replacement at safety net hospitals

Abstract

Background: Safety-net hospitals care for a high proportion of uninsured/underinsured patients who may lack access to longitudinal care. The present study characterized the use of mechanical valves and clinical outcomes of surgical aortic valve replacement at safety net hospitals. Methods: All adults undergoing surgical aortic valve replacement were abstracted from the 2016–2018 Nationwide Readmissions Database. Hospitals were divided into quartiles based on volume of all Medicaid and uninsured admissions, with the highest quartile defined as safety net hospitals. Multivariable regression was used to determine the association between safety net hospitals and several outcomes including mechanical valve use, perioperative complications, index hospitalization costs, 90-day readmission, and complications at readmission. Results: Of the 94,580 patients undergoing surgical aortic valve replacement, 14.5% of operations were at safety net hospitals. Patients at safety net hospitals more commonly received mechanical valves (20.3% vs 16.9%, P < .01) compared to those at non–safety net hospitals. After adjustment, safety net hospitals remained associated with a greater odds of mechanical aortic valve use (adjusted odds ratio, 1.13, 95% confidence interval 1.05–1.21). However, operation at safety net hospitals was also associated with increased odds of perioperative complications (adjusted odds ratio 1.10, 95% confidence interval 1.03–1.17) and higher hospitalization costs (β coefficient +$6.15K, 95% confidence interval +$5.26− +$7.03) despite similar 90-day readmissions. Upon readmission, safety net hospitals patients were more likely to experience mortality (adjusted odds ratio 1.87, 95% confidence interval 1.18–2.98) and stroke (adjusted odds ratio 2.41, 95% confidence interval 1.23–4.70) compared to those at non–safety net hospitals. Conclusion: Hospital safety net status is associated with increased use of mechanical valves for surgical aortic valve replacement despite also being associated with increased perioperative complications, costs, and significant complications upon readmission. Ability to access adequate follow-up care may be an important consideration for surgical aortic valve replacement at safety net hospitals.