Cost-effectiveness of Transcatheter Aortic Valve Implantation - What is the Evidence?
In order to apply the concepts presented above to TAVI, it is useful to distinguish four different types of data sources available to guide medical and economic decision-making:
We will briefly review the evidence for TAVI in these categories using a selection of the current literature and then discuss some related caveats.
Most of the clinical evidence currently available on TAVI is drawn from national or trans-national registries such as FRench Aortic National CoreValve and Edwards (FRANCE), PARTNER EU or Edwards SAPIEN Aortic Bioprosthesis European Outcome (SOURCE), which suggest that TAVI is a safe and clinically effective intervention.7-9 To date, a single randomised controlled trial (RCT) has demonstrated that TAVI is a clinically effective intervention - the PARTNER trial, led in the US.10 One-year mortality outcomes in the PARTNER trial showed that TAVI was non-inferior to surgical aortic valve replacement (SAVR) in patients who were eligible for SAVR (cohort A), and superior to the standard treatment in patients who were ineligible for SAVR (cohort B). The findings of the two-year follow-up with respect to mortality and adverse events were consistent with those of the one-year follow-up.11,12 TAVI was also associated with improvement in quality of life, although results varied by cohort.13
Alongside some of the above-mentioned studies, data on cost have been collected and analysed. Costing studies are generally descriptive and aim at informing about the exact cost that an innovation incurs for a specific type of payer. The latter can be a hospital, health insurance or the patient, and the results of a costing study can vary greatly depending on the perspective taken. In France, for instance, the mean initial hospital stay cost related to TAVI was €35,164 (US$40,619) to the hospital, based on the materials, human resources and overhead costs incurred by 287 patients of a national registry in 2009.14 Using a similar approach, patients in the PARTNER B cohort were reported to incur a cost of US$78,542 to the hospital in 2010.15 The authors of the French study further reportedthat since August 2012 (taking into account a decrease in hospital cost over time), the mean tariff for a TAVI hospital stay is €3,000 (US$3,500) below the cost to the hospital, which means that there is a gap between the cost incurred by the hospital and the reimbursement obtained.