Aortic stenosis (AS) is the most common valvular heart disease, with a dismal prognosis when untreated. Recommended therapy is surgical (SAVR) or transcatheter (TAVR) aortic valve replacement. Based on a retrospective cohort of isolated SAVR and TAVR procedures performed in Germany in 2015 (N = 17,826), we examine the impact of treatment selection on in-hospital mortality and total in-hospital costs for a variety of at-risk populations. Since patients were not randomized to the two treatment options, the two endpoints in-hospital mortality and reimbursement are analyzed using logistic and linear regression models with 20 predefined patient characteristics as potential confounders. Incremental cost-effectiveness ratios were calculated as a ratio of the risk-adjusted reimbursement and mortality differences with 95% confidence intervals obtained by Fieller's theorem. Our study shows that TF-TAVR is more costly that SAVR and that cost differences between the procedures vary little between patient groups. Results regarding in-hospital mortality are mixed. SAVR is the predominant procedure among younger patients. For patients older than 85 years or at intermediate and higher pre-operative risk TF-TAVR seems to be the treatment of choice. Incremental cost-effectiveness ratios (ICER) are most favorable for patients older than 85 years (ICER €154,839, 95% CI €89,163-€302,862), followed by patients at higher pre-operative risk (ICER €413,745, 95% CI €258,027-€952,273). A hypothetical shift from SAVR towards TF-TAVR among patients at intermediate pre-operative risk is associated with a less favorable ICER (€1,486,118, 95% CI €764,732-€23,692,323), as the risk-adjusted mortality benefit is relatively small (- 0.97% point), while the additional reimbursement is still eminent (+€14,464). From a German healthcare system payer's perspective, the additional costs per life saved due to TAVR are most favorable for patients older than 85 and/or at higher pre-operative risk.
Keywords: Cost; ICER; Surgical aortic valve replacement; Transcatheter aortic valve replacement.