OBJECTIVES: Aortic stenosis is the most common valvular heart disease in the elderly - it is estimated that its prevalence is up to 5% in individuals over 75 years. Its standard treatment is surgical valve replacement; however the surgical risk is very high for patients with advanced age and with the association of comorbidities. Thus, a significant proportion of patients become ineligible for this therapy. Treatment with transcatheter aortic valve implantation (TAVI) is a therapy with potentially lower risk peri-procedure and has been used as a therapeutic option in this group of patients considered inoperable. The aim of this study was to develop a cost-effectiveness analysis of the SAPIEN® valve implantation in patients with severe aortic stenosis who are not eligible for surgical treatment. METHODS: A Markov model was developed to compare the SAPIEN® transcatheter implantation therapy versus drug treatment with or without aortic balloon valvoplasty. The outcomes used were effectiveness (as measured by clinical outcomes chance of successful implantation procedure and survival) and safety. The results were expressed as the reason of incremental cost-effectiveness ratio (ICER) per years saved and years free from serious adverse events. Probabilistic sensitivity analysis was performed on the main parameters of the model.  RESULTS: Compared with medical therapy with or without aortic balloon valvuloplasty, the employment of the SAPIEN® valve presents safety in the procedure, increased survival and compatible ICER – US$ 40.000/  life of year saved. CONCLUSIONS: The use of SAPIEN® transcatheter implantation results in improved survival and functional improvement in patients with low risk of serious adverse events, and demonstrates a cost-effectiveness profile when compared to other technologies already incorporated by the Brazilian public health system.