Cost-effectiveness analysis of transcatheter aortic valve implantation versus surgical aortic valve replacement in patients with severe aortic stenosis at low risk of surgical mortality in Sweden

Abstract

Background: Transcatheter aortic valve implantation (TAVI) has shown similar or improved clinical outcomes compared with surgical aortic valve replacement (SAVR) in patients with symptomatic severe aortic stenosis at low risk for surgical mortality. This cost-utility analysis compared TAVI with SAPIEN 3 versus SAVR in symptomatic severe aortic stenosis patients at low risk of surgical mortality from the perspective of the Swedish healthcare system.

Methods: A published, two-stage, Markov-based cost-utility model that captured clinical outcomes from the Swedish Web-system for Enhancement and Development of Evidence-based care in Heart disease Evaluated according to Recommended Therapies (SWEDEHEART) registry (2018-2020) was adapted from the perspective of the Swedish healthcare system using local general population mortality, utility and costs data. The model had a lifetime horizon. Model outputs included changes in direct healthcare costs and health-related quality of life from using TAVI as compared with SAVR.

Results: TAVI with SAPIEN 3 resulted in lifetime costs per patient of 484,142 SEK Swedish krona (SEK) and lifetime quality-adjusted life years (QALYs) per patient of 7.16, whilst SAVR resulted in lifetime costs and QALYs per patient of 457,625 SEK and 6.81 QALYs, respectively. Compared with SAVR, TAVI offered an incremental improvement of +0.35 QALY per patient at an increased cost of +26,517 SEK per patient over a lifetime horizon, resulting in an incremental cost-effectiveness ratio of 76,532 SEK per QALY gained.

Conclusion: TAVI with SAPIEN 3 is a cost-effective option versus SAVR for patients with symptomatic severe aortic stenosis at low risk for surgical mortality treated in the Swedish healthcare setting. These findings may inform policy decisions in Sweden for the management of this patient group.

Keywords: Transcatheter aortic valve implantation; aortic stenosis; cost-effectiveness; low risk; surgical aortic valve replacement.

Figure 1

The cost-effectiveness model had two stages: (A) early AEs from the PARTNER 3 trial were captured in a decision tree, which fed into (B) a Markov model that captured longer-term outcomes of patients, with four distinct health states.^a Reproduced from Gilard M, et al. (15); https://doi.org/10.1016/j.jval.2021.10.003 under the terms of the creative commons licence (Creative Commons Attribution License (CC BY)). ^a‘Alive and well’: patients have undergone the procedure and survived with only short-term or no AEs; patients in this health state can transition to ‘disabling stroke’, ‘AF’ or ‘dead’ at any point during the model time horizon. ‘Treated AF’: patients have undergone the procedure and survived but developed AF requiring specific treatment; this can either occur within the first 30 days or during the rest of the time horizon of the model, and patients in this health state can transition to ‘disabling stroke’ or ‘dead’ at any point during the model time horizon. ‘Disabling stroke’: patients have undergone the procedure and survived but had a disabling stroke; this can either occur within the first 30 days or during the rest of the time horizon of the model, and patients in this health state can only transition into the ‘dead’ state at any point during the model time horizon. ‘Dead’: this is the absorbing state in the model: all patients in the model are at risk of dying due to general all-cause mortality; patients with treated AF and stroke are at an increased risk of dying. AE, adverse event; AF, atrial fibrillation; SAVR, surgical aortic valve replacement; TAVI, transcatheter aortic valve implantation.

Figure 2

Cost breakdown for TAVI with SAPIEN 3 and for SAVR. AF, atrial fibrillation; SAVR, surgical aortic valve replacement; TAVI, transcatheter aortic valve implantation.

Figure 3

Probabilistic sensitivity analysis: (a) cost-effectiveness scatter plot and (b) cost-effectiveness acceptability curve.

Figure 4

Tornado diagram showing the 10 parameters with greatest influence on the model (deterministic sensitivity analysis). AF, atrial fibrillation; SAVR, surgical aortic valve replacement; TAVI, transcatheter aortic valve implantation.