Cost–Utility Analysis of Transcatheter Aortic Valve Implantation versus Surgery in High-Risk Severe Aortic Stenosis Patients in Thailand

BACKGROUND: Transcatheter aortic valve implantation (TAVI) has been shown to be effective in treating patients with severe symptomatic AS who are high-risk population for conventional surgical aortic valve replacement (SAVR). This study aimed to evaluate the cost–utility of TAVI compared with SAVR for severe aortic stenosis with high surgical risk in Thailand. METHODS: Lifetime costs and quality-adjusted life years (QALYs) from societal and healthcare perspectives were estimated using a two-part constructed model. The study population consisted of 80-year-old severe AS patients with high surgical risk. Mortality and complication rates were obtained from landmark trials. All cost–related and utility data were based on Thai population. Costs and QALYs were discounted at a rate of 3% annually and presented as 2021 values. Incremental cost-effectiveness ratios (ICERs) were computed. Sensitivity analyses were performed both deterministically and probabilistically. RESULTS: The findings from a societal perspective revealed that TAVI treatment was associated with higher cost (THB 1,551,895 [USD 47,371.64] vs THB 548,438 [USD 16,741.09] and higher QALYs than SAVR treatment (3.15 vs 2.31 QALYs). The estimated ICER was THB 1,196,191/QALY (USD 36,513.78 QALY). For the healthcare system perspective, TAVI treatment resulted in a higher total cost than SAVR treatment (THB 1,451,317 [USD 44,301.49] vs THB 432,398 [USD 13,198.95]) with comparable gains in LY and QALYs from a societal perspective. The ICER was calculated to be THB 1,214,624/QALY (USD 37,076.42/QALY). TAVI was not cost-effective at the Thai willingness to pay (WTP) threshold of THB 160,000/QALY (USD 4884/QALY). The model was the most sensitive to changes in TAVI valve cost and TAVI or SAVR treatment utilities. CONCLUSION: TAVI is not a cost-effective strategy in patients with severe AS who are at high surgical risk when compared to SAVR at the WTP of THB 160,000/QALY (USD 4884/QALY) from the perspectives of society and the healthcare system.