Predictors of cumulative cost for patients with severe aortic stenosis referred for surgical or transcatheter aortic valve replacement: a population-based study in Ontario, Canada

Aims — Transcatheter aortic valve replacement (TAVR) as an alternative to surgical aortic valve replacement (SAVR) has transformed severe aortic stenosis (AS) management. Our aim was understand AS cost drivers from referral to 1-year post procedure.

Methods — We identified patients referred for either TAVR/SAVR between April 1st, 2015 to March 31st, 2018, with follow-up until March 31st, 2019 in Ontario, Canada. We stratified costs into: 1) a referral phase 2) a procedural phase from the procedure date to 60 days post-procedure 3) post-procedure phase from 61 days to 1 year. Multivariable regression modeling using generalized linear models with a log link gamma distribution was used to identify cost drivers in each phase.

Results — The study cohort included 12,086 AS patients; 4,832 were referred for TAVR and 7,254 were referred for SAVR. The median cost for TAVR was higher than SAVR in the referral ($3,593 vs $2,944) and post-procedural ($5,938 vs $3,257) phases. In contrast, for the procedural phase, SAVR had a median cost of $29,756 vs. $27,907 for TAVR. Predictors of high cost in the referral phase were longer wait-time, and an urgent in-hospital procedure. In the procedural phase, procedural complications were the major drivers of higher cost. In the post-procedural phase, patient comorbidities were the major drivers, specifically dialysis, liver disease, cancer, peripheral vascular disease (PVD), and diabetes mellitus.

Conclusion — We identified distinct patterns of cost accumulation and modifiable drivers for SAVR compared to TAVR; these drivers may guide clinical and health policy decisions to make AS care more efficient.