PMD12 - Cost-Effectiveness of Transfemoral Aortic Valve Implantation Compared with Surgical Aortic Valve and Medical Management in Patients with Severe Symptomatic Aortic Stenosis in Australia

Abstract

Transcatheter aortic valve implantation (TAVI) has emerged as an alternative for treating aortic stenosis, particularly in patients who are poor candidates for surgical aortic valve replacement. In Australia, TAVI is not yet subsidised on the Medicare Benefits Schedule. The purpose of this study was to assess the cost-effectiveness of transfemoral aortic valve replacement interventions (TAVI-TF) compared with surgical aortic valve replacement and with medical management in patients with symptomatic severe aortic valve stenosis from an Australian healthcare provider perspective. We constructed a Markov model-based probabilistic cost-effectiveness analysis and compared TAVI-TF with surgical aortic valve replacement and with medical management, in terms of lifetime costs, quality-adjusted life years, and cost-effectiveness. The model considered two patient populations: high surgical risk patients and inoperable patients. Overall survival was based on the 5-year published data of the PARTNER trial. Costs were estimated using published data and included the cost of the intervention, index hospitalization, adverse events, follow-up care, and end-of-life care. Utilities were derived from the published PARTNER studies. A 5% discount rate was used for both costs and health outcomes. Deterministic and probabilistic sensitivity analysis was performed to explore uncertainties around assumptions and model input parameters. In the base case, if TAVI-TF is available, the cost per quality-adjusted life year gained is $55,843 in the high-risk cohort and $1,392 for the inoperable cohort. The economic model is most sensitive to the cost of index hospitalization and the cost of the valve system. Transfemoral TAVI compared with surgical aortic valve replacement is cost-effective in Australia if the price of the device is lower. Transfemoral TAVI compared with medical management is cost-effective in Australia for inoperable patients. The sensitivity analyses provided enable decision makers in other countries with similar health care practices to Australia to determine the acceptability of cost-effectiveness ratios according to their willingness-to-pay thresholds.