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

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. 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. 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. 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.