POSA137 Cost-Effectiveness Analysis of a New Anticalcification Treatment Tissue Valve Vs. Mechanical Heart Valves in Subgroups of People Aged 55-64 and >65 with Aortic Stenosis (AS) Suitable for Surgical Aortic Valve Replacement (SAVR)

To determine the cost-effectiveness of using either a new anticalcification treatment tissue valve compared with mechanical heart valves in the two subgroups of patients aged 55-64 and >65 with AS suitable for SAVR from a UK NHS perspective A decision-analytic model was developed which combined a decision tree to capture early events within the first 30 days, and a partition survival model, capturing the health states: functional heart valve, disabling stroke and dead. Other events (reoperation, endocarditis and bleeding) were considered by applying one-off costs and utility decrements: for endocarditis there is no difference in the occurrence due to interventions. Parameter inputs were obtained from published literature, using UK specific sources where possible. Deterministic sensitivity analyses (DSA) and probabilistic sensitivity analyses (PSA) were conducted to assess the robustness of Results: The base case results suggested the new anticalcification treatment tissue valve was associated with higher quality-adjusted life year (QALY) gains for both subgroups, with slightly higher costs versus mechanical valves for those aged 55-64 but lower costs for those aged >65, resulting in incremental cost effectiveness ratios (ICERs) of £1,151 and a dominant ICER, respectively. DSA indicated the results of the model to be dependent on the relative differences in mortality and procedure costs between valves. PSA estimated 92.4% of iterations to be cost-effective for the new anticalcification treatment tissue valve compared to mechanical valves for people aged 55-64, with a similar figure for those aged >65. Based on current available evidence, the analysis suggests that newer anticalcification treatment tissue valves could be a cost-effective use of resources for patients with AS who are suitable for SAVR in the UK NHS over the age of 55-64 and >65.